WO2025157365A1

WO2025157365A1 - Container handling vehicle

Info

Publication number: WO2025157365A1
Application number: PCT/EP2024/051333
Authority: WO
Inventors: Trond Austrheim; Ivar Fjeldheim
Original assignee: Autostore Technology AS
Current assignee: Autostore Technology AS
Priority date: 2024-01-22
Filing date: 2024-01-22
Publication date: 2025-07-31
Anticipated expiration: 2026-07-22

Abstract

A container handling vehicle (501) for an automated storage and retrieval system comprises: a vehicle frame (10); a first set of wheels for driving in a first direction (X); and a second set of wheels for driving in a second direction (Y). The vehicle frame (10) defines a first section (S1), a second section (S2) and a third section (S3) of the container handling vehicle arranged side-by-side, wherein the second section (S2) comprises a cavity (26) for accommodating a storage container (106), and wherein the first section (S1) is arranged on a first side of the second section (S2) and the third section (S3) is arranged on an opposite second side of the second section (S2). The first set of wheels (11) are arranged to be movable in a vertical direction (Z) relative to the vehicle frame (10) between an upper position in which the second set of wheels (12) allows movement of the container handling vehicle (501) along the second direction (Y), and a lower position in which the first set of wheels (11) allows movement of the container handling vehicle (501) along the first direction (X). A single coupler link system (14';14-1,14-2,14-3) is arranged to couple the first wheel (11a) and second wheel (11b) of the first set of wheels to the third wheel (11c) and fourth wheel (11d) of the first set of wheels to enable the wheels of the first wheel set to move together in the vertical direction (Z) relative to the frame. The coupler link system (14';14-1,14-2,14-3) may be arranged on one side of the container handling vehicle only.

Description

CONTAINER HANDLING VEHICLE

[ooi] The present invention relates to a container handling vehicle for an automated storage and retrieval system. The present invention also relates to an associated method of assembling.

BACKGROUND AND PRIOR ART

[002] Fig. 1 discloses a prior art automated storage and retrieval system 1 with a frame structure 100 and Figs. 2, 3 and 4 disclose three different prior art container handling vehicles 201,301,401 suitable for operating on such a system 1.

[003] The frame structure 100 comprises upright members 102 and a storage volume comprising storage columns 105 arranged in rows between the upright members 102. In these storage columns 105 storage containers 106, also known as bins, are stacked one on top of one another to form stacks 107. The members 102 may typically be made of metal, e.g. extruded aluminum profiles.

[004] The frame structure 100 of the automated storage and retrieval system 1 comprises a rail system 108 arranged across the top of frame structure 100, on which rail system 108 a plurality of container handling vehicles 201,301,401 may be operated to raise storage containers 106 from, and lower storage containers 106 into, the storage columns 105, and also to transport the storage containers 106 above the storage columns 105. The rail system 108 comprises a first set of parallel rails no arranged to guide movement of the container handling vehicles 201,301,401 in a first direction X across the top of the frame structure 100, and a second set of parallel rails 111 arranged perpendicular to the first set of parallel rails no to guide movement of the container handling vehicles 201,301,401 in a second direction Y which is perpendicular to the first direction X. Containers 106 stored in the columns 105 are accessed by the container handling vehicles 201,301,401 through access openings 112 in the rail system 108. The container handling vehicles 201,301,401 can move laterally above the storage columns 105, i.e. in a plane which is parallel to the horizontal X-Y plane.

[005] The upright members 102 of the frame structure 100 may be used to guide the storage containers during raising of the containers out from and lowering of the containers into the columns 105. The stacks 107 of containers 106 are typically self-supporting. [oo6] Each prior art container handling vehicle 201,301,401 comprises a vehicle body 201a, 301a, 401a and first and second sets of wheels 201b, 201c, 301b, 301c, 401b, 401c which enable the lateral movement of the container handling vehicles 201,301,401 in the X direction and in the Y direction, respectively. In Figs. 2, 3 and 4 two wheels in each set are fully visible. The first set of wheels 201b, 301b, 401b is arranged to engage with two adjacent rails of the first set of parallel rails no, and the second set of wheels 201c, 301c, 401c is arranged to engage with two adjacent rails of the second set of parallel rails 111. At least one of the sets of wheels 201b, 201c, 301b, 301c, 401b, 401c can be lifted and lowered, so that the first set of wheels 201b, 301b, 401b and/or the second set of wheels 201c, 301c, 401c can be engaged with the respective set of parallel rails no, 111 at any one time.

[007] Each prior art container handling vehicle 201,301,401 also comprises a lifting device for vertical transportation of storage containers 106, e.g. raising a storage container 106 from, and lowering a storage container 106 into, a storage column 105. The lifting device comprises one or more gripping / engaging devices which are adapted to engage a storage container 106, and which gripping / engaging devices can be lowered from the vehicle 201,301,401 so that the position of the gripping / engaging devices with respect to the vehicle 201,301,401 can be adjusted in a third direction Z which is orthogonal the first direction X and the second direction Y. Parts of the gripping device of the container handling vehicles 301,401 are shown in Figs. 3 and 4 indicated with reference number 304,404. The gripping device of the container handling device 201 is located within the vehicle body 201a in Fig. 2 and is thus not shown. The lifting device may comprise a lifting frame 4O4d suspended from lifting bands 404a. The lifting bands 404a may provide power and communication between the container handling vehicle and the lifting frame 4O4d. The lifting frame 404b may comprise gripping engaging devices/grippers 404b for connection to gripping recesses of a storage container 106. Guide pins 404c assist in aligning the grippers 404b relative the gripping recesses of the storage container 106.

[008] Conventionally, and also for the purpose of this application, Z=i identifies the uppermost layer available for storage containers below the rails 110,111, i.e. the layer immediately below the rail system 108, Z=2 the second layer below the rail system 108, Z=3 the third layer etc. In the exemplary prior art disclosed in Fig. 1, Z=8 identifies the lowermost, bottom layer of storage containers. Similarly, X=i...n and Y=i...n identifies the position of each storage column 105 in the horizontal plane. Consequently, as an example, and using the Cartesian coordinate system X, Y, Z indicated in Fig. 1, the storage container identified as 106’ in Fig. 1 can be said to occupy storage position X=i , Y=i, Z=6. The container handling vehicles 201,301,401 can be said to travel in layer Z=o, and each storage column 105 can be identified by its X and Y coordinates. Thus, the storage containers shown in Fig. 1 extending above the rail system 108 are also said to be arranged in layer Z=o.

[009] The storage volume of the frame structure 100 has often been referred to as a grid 104, where the possible storage positions within this grid are referred to as storage cells. Each storage column may be identified by a position in an X- and T-direction, while each storage cell may be identified by a container number in the X-, Y- and Z-direction.

[0010] Each prior art container handling vehicle 201,301,401 comprises a storage compartment or space for receiving and stowing a storage container 106 when transporting the storage container 106 across the rail system 108. The storage space may comprise a cavity arranged internally within the vehicle body 201a, 401a as shown in Figs. 2 and 4 and as described in e.g. WO2O15/193278A1 and W02019/206487A1, the contents of which are incorporated herein by reference.

[0011] Fig. 3 shows an alternative configuration of a container handling vehicle 301 with a cantilever construction. Such a vehicle is described in detail in e.g. NO317366, the contents of which are also incorporated herein by reference.

[0012] The cavity container handling vehicle 201 shown in Fig. 2 may have a footprint that covers an area with dimensions in the X and Y directions which is generally equal to the lateral extent of a storage column 105, e.g. as is described in WO2O15/193278A1, the contents of which are incorporated herein by reference. The term ‘lateral’ used herein may mean ‘horizontal’.

[0013] Alternatively, the cavity container handling vehicles 401 may have a footprint which is larger than the lateral area defined by a storage column 105 as shown in Fig. 1 and 4, e.g. as is disclosed in W02014/090684A1 or W02019/206487A1.

[0014] The rail system 108 typically comprises rails with grooves in which the wheels of the vehicles run. Alternatively, the rails may comprise upwardly protruding elements, where the wheels of the vehicles comprise flanges to prevent derailing. These grooves and upwardly protruding elements are collectively known as tracks. Each rail may comprise one track, or each rail 110,111 may comprise two parallel tracks. In other rail systems 108, each rail in one direction (e.g. an X direction) may comprise one track and each rail in the other, perpendicular direction (e.g. a Y direction) may comprise two tracks. Each rail 110,111 may also comprise two track members that are fastened together, each track member providing one of a pair of tracks provided by each rail.

[0015] W02018/146304A1, the contents of which are incorporated herein by reference, illustrates a typical configuration of rail system 108 comprising rails and parallel tracks in both X and Y directions.

[0016] In the frame structure 100, a majority of the columns 105 are storage columns 105, i.e. columns 105 where storage containers 106 are stored in stacks 107. However, some columns 105 may have other purposes. In Fig. 1, columns 119 and 120 are such special-purpose columns used by the container handling vehicles 201,301,401 to drop off and/or pick up storage containers 106 so that they can be transported to an access station (not shown) where the storage containers 106 can be accessed from outside of the frame structure 100 or transferred out of or into the frame structure 100. Within the art, such a location is normally referred to as a ‘port’ and the column in which the port is located maybe referred to as a ‘port column’ 119,120. The transportation to the access station maybe in any direction, that is horizontal, tilted and/or vertical. For example, the storage containers 106 maybe placed in a random or dedicated column 105 within the frame structure 100, then picked up by any container handling vehicle and transported to a port column 119,120 for further transportation to an access station. The transportation from the port to the access station may require movement along various different directions, by means such as delivery vehicles, trolleys or other transportation lines. Note that the term ‘tilted’ means transportation of storage containers 106 having a general transportation orientation somewhere between horizontal and vertical.

[0017] In Fig. 1, the first port column 119 may for example be a dedicated drop-off port column where the container handling vehicles 201,301,401 can drop off storage containers 106 to be transported to an access or a transfer station, and the second port column 120 may be a dedicated pick-up port column where the container handling vehicles 201,301,401 can pick up storage containers 106 that have been transported from an access or a transfer station.

[0018] The access station may typically be a picking or a stocking station where product items are removed from or positioned into the storage containers 106. In a picking or a stocking station, the storage containers 106 are normally not removed from the automated storage and retrieval system 1, but are returned into the frame structure 100 again once accessed. A port can also be used for transferring storage containers to another storage facility (e.g. to another frame structure or to another automated storage and retrieval system), to a transport vehicle (e.g. a train or a lorry), or to a production facility.

[0019] A conveyor system comprising conveyors is normally employed to transport the storage containers between the port columns 119,120 and the access station.

[0020] If the port columns 119,120 and the access station are located at different levels, the conveyor system may comprise a lift device with a vertical component for transporting the storage containers 106 vertically between the port column 119,120 and the access station.

[0021] The conveyor system may be arranged to transfer storage containers 106 between different frame structures, e.g. as is described in W02014/075937A1, the contents of which are incorporated herein by reference.

[0022] A storage system may also use port columns 119,120 to transfer a storage container between the rail system 108 on top of the frame structure 100 and a container transfer vehicle arranged below a lower end of the port column. Such storage systems and suitable container transfer vehicles are disclosed in WO 2019/238694 Al and WO 2019/238697 Al, the contents of which are incorporated herein by reference.

[0023] A potential disadvantage of using a container transfer vehicle to retrieve and deliver storage containers from/to the lower end of a port column is the time dependency between the container transfer vehicle(s) and the container handling vehicles used to retrieve/deliver the storage containers through the port column.

[0024] When a storage container 106 stored in one of the columns 105 disclosed in Fig. 1 is to be accessed, one of the container handling vehicles 201,301,401 is instructed to retrieve the target storage container 106 from its position and transport it to the drop-off port column 119. This operation involves moving the container handling vehicle 201,301,401 to a location above the storage column 105 in which the target storage container 106 is positioned, retrieving the storage container 106 from the storage column 105 using the container handling vehicle’s 201,301,401 lifting device (not shown), and transporting the storage container 106 to the drop-off port column 119. If the target storage container 106 is located deep within a stack 107, i.e. with one or a plurality of other storage containers 106 positioned above the target storage container 106, the operation also involves temporarily moving the abovepositioned storage containers prior to lifting the target storage container 106 from the storage column 105. This step, which is sometimes referred to as “digging” within the art, may be performed with the same container handling vehicle that is subsequently used for transporting the target storage container to the drop-off port column 119, or with one or a plurality of other cooperating container handling vehicles. Alternatively, or in addition, the automated storage and retrieval system 1 may have container handling vehicles 201,301,401 specifically dedicated to the task of temporarily removing storage containers 106 from a storage column 105. Once the target storage container 106 has been removed from the storage column 105, the temporarily removed storage containers 106 can be repositioned into the original storage column 105.

However, the removed storage containers 106 may alternatively be relocated to other storage columns 105.

[0025] When a storage container 106 is to be stored in one of the columns 105, one of the container handling vehicles 201,301,401 is instructed to pick up the storage container 106 from the pick-up port column 120 and transport it to a location above the storage column 105 where it is to be stored. After any storage containers 106 positioned at or above the target position within the stack 107 have been removed, the container handling vehicle 201,301,401 positions the storage container 106 at the desired position. The removed storage containers 106 may then be lowered back into the storage column 105, or relocated to other storage columns 105.

[0026] For monitoring and controlling the automated storage and retrieval system 1, e.g. monitoring and controlling the location of respective storage containers 106 within the frame structure 100, the content of each storage container 106; and the movement of the container handling vehicles 201,301,401 so that a desired storage container 106 can be delivered to the desired location at the desired time without the container handling vehicles 201,301,401 colliding with each other, the automated storage and retrieval system 1 comprises a control system 500 which typically is computerized and which typically comprises a database for keeping track of the storage containers 106. [0027] An aim of the invention to providing an improved vehicle that can more reliably carry larger/heavier containers.

[0028] Another aim is to provide a container handling vehicle with an improved wheel lift mechanism.

SUMMARY OF THE INVENTION

[0029] This summary is provided to introduce in simplified form a selection of concepts that are further described herein. The summary is not intended to identify key or essential features of the invention.

[0030] The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention.

[0031] The present invention relates to a container handling vehicle comprising a first section, a second section and a third section, wherein the first section is arranged on a first side of the second section and the third section is arranged on an opposite second side of the second section. A first drive motor may be arranged in the first section and a second drive motor may be arranged in the third section. A single coupler link system arranged on one side of the container handling vehicle only is used during rotation of a first and second pair of wheel links connected to a first set of wheels and a second set of wheels respectively. The one, i.e. the single, coupler link system is thus the only coupler link system used in moving the first set of wheels and second set of wheels in the Z direction.

[0032] It is described a container handling vehicle for an automated storage and retrieval system, the container handling vehicle comprising: a vehicle frame; a first set of wheels for driving in a first direction; a second set of wheels for driving in a second direction; wherein the vehicle frame defines a first section, a second section and a third section of the container handling vehicle arranged side-by-side, wherein the second section comprises a cavity for accommodating a storage container, and wherein the first section is arranged on a first side of the second section and the third section is arranged on an opposite second side of the second section; wherein the first set of wheels comprises a first wheel, a second wheel, a third wheel and a fourth wheel for driving in the first direction, wherein the first wheel and the second wheel are arranged in the first section and linked by a first cross-member, and the third wheel and the fourth wheel are arranged in the third section and linked by a second cross-member; wherein the first set of wheels are arranged to be movable in a vertical direction relative to the vehicle frame between an upper position in which the second set of wheels allows movement of the container handling vehicle along the second direction, and a lower position in which the first set of wheels allows movement of the container handling vehicle along the first direction; wherein a single coupler link system is arranged to couple the first wheel and second wheel to the third wheel and fourth wheel to enable the wheels of the first wheel set to move together in the vertical direction relative to the frame.

[0033] The automated storage and retrieval system may comprise a two- dimensional rail system comprising a first set of parallel rails in a horizontal plane arranged to guide movement of container handling vehicles in the first direction across the top of a frame structure, and a second set of parallel rails in the horizontal plane arranged perpendicular to the first set of parallel rails to guide movement of the container handling vehicles in the second direction. The first direction may be perpendicular to the second direction.

[0034] The container handling vehicle may comprise: a first drive motor for driving the first wheel and the second wheel of the first set of wheels; a second drive motor for driving the third wheel and the fourth wheel of the first set of wheels; wherein the first drive motor is arranged in the first section, and the second drive motor is arranged in the third section.

[0035] The second set of wheels may comprises a first wheel, a second wheel, a third wheel and a fourth wheel for driving in the second direction. The container handling vehicle may comprise a third drive motor for driving the first wheel and the fourth wheel of the second set of wheels. The third drive motor may be arranged in the first section.

[0036] The container handling vehicle may comprise a fourth drive motor for driving the second wheel and the third wheel of the second set of wheels. The fourth drive motor may be arranged in the third section.

[0037] The container handling vehicle may comprise a first lifting device motor. The first lifting device motor may be arranged in the first section. [0038] The container handling vehicle may be an all-wheel drive container handling vehicle.

[0039] It is described a container handling vehicle for operation on an automated storage and retrieval system, the automated storage and retrieval system comprising a two-dimensional rail system comprising a first set of parallel rails in a horizontal plane arranged to guide movement of container handling vehicles in a first direction across the top of a frame structure, and a second set of parallel rails in the horizontal plane arranged perpendicular to the first set of parallel rails to guide movement of the container handling vehicles in a second direction which is perpendicular to the first direction, the container handling vehicle comprises: a vehicle frame defining a first section, a second section and a third section of the container handling vehicle arranged side-by-side, wherein the first section is arranged on a first side of the second section and the third section is arranged on an opposite second side of the second section; the second section comprises a cavity for accommodating a storage container; a first set of wheels comprising a first wheel, a second wheel, a third wheel and a fourth wheel for driving in the first direction; a second set of wheels comprising a first wheel, a second wheel, a third wheel and a fourth wheel for driving in the second direction; a first drive motor for driving the first wheel and the second wheel of the first set of wheels; a second drive motor for driving the third wheel and the fourth wheel of the first set of wheels; and wherein the first wheel and the second wheel of the first set of wheels and the first drive motor are arranged in the first section, and the third wheel and the fourth wheel of the first set of wheels and the second drive motor are arranged in the third section; wherein the first set of wheels being arranged to be movable in a vertical direction relative to the vehicle frame between an upper position in which the second set of wheels allows movement of the vehicle along the second direction, and a lower position in which the first set of wheels allows movement of the vehicle along the first direction; and wherein: the third wheel of the first set of wheels is mounted to a first wheel link of a first pair of wheel links and the fourth wheel of the first set of wheels is mounted to a second wheel link of the first pair of wheel links, each first and second wheel links of the first pair of wheel links comprises a first pivot coupling and the first wheel link of the first pair of wheel links comprises a second pivot coupling and each of the first and second wheel links of the first pair of wheel links is pivotably connected to the vehicle frame by the first pivot coupling; the first wheel of the first set of wheels is mounted to a first wheel link of a second pair of wheel links and the second wheel of the first set of wheels is mounted to a second wheel link of the second pair of wheel links, each of the first and second wheel link of the second pair of wheel links comprises a third pivot coupling and the first wheel link of the second pair of wheel links comprises a fourth pivot coupling and each first and second wheel links of the second pair of wheel links is pivotably connected to the vehicle frame by the third pivot coupling; the first section comprises a first cross-member fixing the angular position of the first and second wheel links of the second pair of wheel links relative to each other, such that the first and second wheel links of the second pair of wheel links will move in unison around their respective third pivot coupling; and the third section comprises a second cross-member fixing the angular position of the first and second wheel links of the first pair of wheel links relative to each other, such that the first and second wheel links of the first pair of wheel links will move in unison around their respective first pivot coupling; the first wheel link of the first pair of wheel links and the first wheel link of the second pair of wheel links are connected via the respective second and fourth pivot couplings by a single coupler link system.

[0040] The first pair of wheel links and the second pair of wheel links are connected by a single coupler link system connected between the second and fourth pivot couplings on one side of the container handling vehicle only. This reduces the number of components and simplifies manufacturing and assembling of the container handling vehicles.

[0041] The coupler link system is preferably arranged on one side of the container handling vehicle only.

[0042] The coupler link system on only one side of the container handling vehicle is thus the only coupler link system used in moving the first set of wheels and second set of wheels in the Z direction.

[0043] In other words, the first section and the third section are separated by the second section. [0044] The first section, the second section and the third section are preferably arranged side-by-side with the next section in a horizontal plane.

[0045] One access opening including a track of each of the rails adjacent the occupied access opening is also denoted “a grid cell”. A grid cell may be defined as the cross-sectional area, including width of the rails, between the midpoint of two rails running in the first direction and the midpoint of two rails running in the second direction.

[0046] When the second section is directly above a grid cell, the first section extends into a neighboring grid cell and the third section extends into a grid cell on an opposite side.

[0047] The container handling vehicle may comprise a third drive motor for driving the first wheel and the fourth wheel of the second set of wheels. The third drive motor may be arranged in the first section.

[0048] The container handling vehicle may comprise a fourth drive motor for driving the second wheel and the third wheel of the second set of wheels. The fourth drive motor may be arranged in the third section.

[0049] The first wheel and the fourth wheel of the second set of wheels is preferably operatively connected to the third drive motor by a drive band.

[0050] The container handling vehicle may comprise a first lifting device motor, and the first lifting device motor may be arranged in the first section.

[0051] The container handling vehicle may comprise a second lifting device motor, and the second lifting device motor may be arranged in the third section.

[0052] The second section provides a cavity in which a storage container may be accommodated, and the container handling vehicle may comprise a lifting device in the second section for lifting and lowering of the storage container into the cavity, and the first wheel and the fourth wheel of the second set of wheels may be arranged on a first side of the cavity and the second wheel and the third wheel of the second set of wheels may be arranged on an opposite second side of the cavity.

[0053] The lifting device may comprise at least one rotatable lifting shaft configured to raise and lower the lifting frame via a set of lifting bands, the lifting shaft may be arranged in the second section above the cavity. [0054] The first section has a footprint, the second section has a footprint, and a size ratio of the footprint of the second section relative to the footprint of the first section maybe at least 2:1.

[0055] The third section has a footprint, and a size ratio of the footprint of the second section relative to the footprint of the third section may be at least 2:1.

[0056] If both the first section and the third section are smaller than half a grid cell width compared to the second section, this allows passing of two container handling vehicles having the same orientation on 5 grid cells instead of 6 cells because the two container handling vehicles share one grid cell, i.e. each of the container handling vehicles occupies less than 50% of the shared grid cell.

[0057] The third section may comprise an actuator assembly, the actuator assembly may be arranged to move the first and second wheel links of the first pair of wheel links around the respective first pivot couplings between a first angular position and a second angular position, the movement of the first and second wheel links of the first pair of wheel links may be transferred to the first and second wheel links of the second pair of wheel links via the single coupler link system and the first cross-member and the second cross-member, such that the first set of wheels may be in the upper position or the lower position when the first wheel link and the second wheel link of the first pair of wheel links may be in the first angular position or the second angular position, respectively.

[0058] The single coupler link system may be configured to move in the first direction towards the first wheel and the second wheel of the first set of wheels, respectively, when the first and second wheel links of the first pair of wheel links may be moved from the second angular position to the first angular position.

[0059] The actuator assembly may be operatively connected to a wheel lift mechanism and may be arranged to move the first wheel link and the second wheel link of the first pair of wheel links around its first pivot coupling between the first angular position and the second angular position.

[0060] The first set of wheels may be arranged to be movable in a vertical direction relative to the vehicle frame between an upper position in which the second set of wheels allows movement of the vehicle along the second direction, and a lower position in which the first set of wheels allows movement of the vehicle along the first direction.

[0061] The actuator assembly may comprise a wheel lift motor or a linear actuator.

[0062] The first wheel link of the first pair of wheel links may comprise a fifth pivot coupling connected to the actuator assembly.

[0063] The actuator assembly may comprise an actuator link pivotably connected to the first wheel link of the first pair of wheel links to drive rotation of the first wheel link and the second wheel link of the first pair of wheel links.

[0064] The actuator link may be connected to the fifth pivot coupling of the first wheel link of the first pair of wheel links.

[0065] The actuator link may be part of a movement transfer assembly configured to convert a rotational movement, or transfer a linear movement, of the actuator assembly to a substantially linear movement acting on the fifth pivot coupling of the first wheel link of the first pair of wheel links.

[0066] In a first embodiment of the coupler link system the first pair of wheel links and the second pair of wheel links move in the same direction around their respective first pivot coupling and third pivot coupling. I.e. the single coupler link system may be configured to move in the first direction towards the first wheel and the second wheel of the first set of wheels, respectively, when the first wheel link and the second wheel link of the first pair of wheel links are moved from the second angular position to the first angular position. I.e. both the first pair of wheel links and the second pair of wheel links rotate in the same direction when moving the first set of wheels in the Z direction.

[0067] The single coupler link may comprise a wheel recess for the wheel connected to the first wheel link of the first pair of wheel links and the first wheel link of the second pair of wheel links. The single coupler link may feature a first end pivotably connected to the second pivot coupling of the first wheel link of the second pair of wheel links and is pivotably connected to the second pivot coupling of the first wheel link of the first pair of wheel links at a portion of the single coupler link system arranged above the wheel recess.

[0068] The single coupler link system may act as both force transferring element between the first wheel link of the first pair of wheel links and the first wheel link of the second pair of wheel links and bodywork/covering closing off the lower portion of one of the sides of the container handling vehicle.

[0069] The first pivot coupling and the third pivot coupling may be arranged at a level below the second pivot coupling and the fourth pivot coupling.

[0070] A rechargeable battery may be arranged in the third section. Optionally, an additional rechargeable battery may be arranged in the first section.

[0071] The container handling vehicle may comprise a set of electrodes for receiving power from a charging station, the electrodes are preferably arranged in the third section and connected to the rechargeable battery in the third section.

[0072] The container handling vehicle may comprise a control unit arranged in the third section.

[0073] The container handling vehicle may comprise a set of replaceable or adjustable distance pins, the distance pins configured to interact with switches or sensors on the lifting frame when the lifting frame is in an upper position.

[0074] The adjustable or replaceable distance pins ensure that the efficiency of the container handling vehicle may be optimized with respect to the height of the storage containers being lifted. The container handling vehicle may comprise four distance pins arranged to interact with four corner sections of the lifting frame. The distance pins may be configured to stabilize the lifting frame, and any storage container connected thereto, when the lifting frame is in an upper position.

[0075] In a second embodiment of the coupler link system, the coupler link system comprises:

- a rotatable plate rotatably connectable to a rotational shaft of a wheel lift motor;

- a first coupler link connectable between the first wheel link of the second pair of wheel links and the rotatable plate;

- a second coupler link connectable between the first wheel link of the first pair of wheel links and the rotatable plate.

[0076] The second pivot coupling may be configured to rotatably connect the first wheel link of the first pair of wheel links to the second coupler link and the fourth pivot coupling may be configured to rotatably connect the first wheel link of the second pair of wheel links to the first coupler link.

[0077] In accordance with the second embodiment, the first pair of wheel links and the second pair of wheel links move in opposite directions around their respective first pivot coupling and third pivot coupling. I.e. the first pair of wheel links and the second pair of wheel links rotate in opposite directions when moving the first set of wheels in the Z direction

[0078] The container handling vehicle may comprise: a first drive shaft arranged in the first section and interconnecting the first and second wheel links of the second pair of wheel links, wherein the first drive shaft is operatively connected to drive the first wheel and the second wheel of the first set of wheels; and a second drive shaft arranged in the third section and interconnecting the first and second wheel links of the first pair of wheel links, where the second drive shaft may be operatively connected to drive the third wheel and the fourth wheel of the first set of wheels.

[0079] The first drive shaft is preferably operatively connected to drive the first wheel and the second wheel via respective drive bands.

[0080] The second drive shaft is preferably operatively connected to drive the third wheel and the fourth wheel via respective drive bands.

[0081] The first drive shaft may be connected to a first drive such as an electric motor. Rotational movement of the first drive shaft may be transferred to the first wheel and the second wheel of the first set of wheels.

[0082] The second drive shaft may be connected to a second drive such as an electric motor. Rotational movement of the second drive shaft may be transferred to the third wheel and the fourth wheel of the first set of wheels.

[0083] The first drive shaft and the first cross-member and the second drive shaft and the second cross-member may be configured to move in parallel when the first pair of wheel links and the second pair of wheel links are moved between the first and second angular positions.

[0084] The first drive shaft and the second drive shaft may be configured to move in unison with the first wheel links and the second wheel links between the first and second angular position. By moving in unison with the first wheel links and the second wheel links and their respective supported wheels, both excessive wear of the drive bands due to stretching, and service involving tightening of the drive bands, are minimized. The belt lengths, and hence the belt tension remain constant and can be set to a preferred tension, since the wheels and motors supported by the first pair of wheel links and the second pair of wheel links are fixed in a spatial relationship with respect to each other during the angular movement.

[0085] The first drive motor may be fixed to one of the first wheel link or the second wheel link of the first pair of wheel links. The first drive shaft may have a first end and a second end, the first drive shaft may extend through a centerline of the first drive motor, such that the first end is operably connected to the first wheel of the first set of wheels and the second end is operatively connected to the second wheel of the first set of wheels. The first end may be operatively connected to the first wheel by a drive band, and the second end may be operatively connected to the third wheel by a drive band.

[0086] The second wheel and the third wheel of the second set of wheels is preferably operatively connected to the fourth drive motor by a drive band.

[0087] The vehicle frame may comprise a first vertical subframe forming part of the first section and a second vertical subframe forming part of the third section and a horizontal upper member forming part of the second section, and wherein the horizontal upper member may be arranged above the cavity.

[0088] The horizontal upper member may be connected to the first vertical subframe and the second vertical subframe.

[0089] The horizontally extending upper frame is preferably arranged over the lifting frame, in addition to be arranged over the cavity.

[0090] The horizontally extending upper frame may be connected to the first vertical subframe and the second vertical subframe.

[0091] The first and second vertical subframes may be arranged on opposite sides of the cavity.

[0092] The vehicle frame may comprise side cross-members arranged on opposite sides of the cavity. [0093] The side cross-members may be horizontal members connected to lower portions of the first and second vertical subframes. Alternatively, the side cross-members may form cross connections connected to a lower portion of one of the first or second vertical subframe and to an upper portion of the other of the first and second vertical subframe.

[0094] It is further described a container handling vehicle comprising a first section, a second section and a third section, the first section and the third section comprise drive motors on hinged wheel assemblies for driving wheels arranged in the respective first section and third section, and the hinged wheel assemblies of the first section and the third section may be connectable on opposite sides of the second section. As such, the container handling vehicle is assembled.

[0095] The automated storage and retrieval system may comprise a frame structure having a plurality of storage columns for accommodating vertical stacks of storage containers, the frame structure having a rail system upon which the container handling vehicle may move in two perpendicular directions above the storage columns.

[0096] The automated storage and retrieval system may comprise a plurality of upright members and each storage column may be defined by four of the upright members.

[0097] The rail system may be arranged on top of the upright members, the rail system comprising a first set of parallel rails and a second set of parallel rails arranged perpendicular to the first set of rails. The first and second set of rails providing a horizontal grid-based rail system defining a plurality of grid cells. The rails of the rail system may comprise one or two tracks. Preferably both directions of rail comprise two tracks, e.g., either as two parallel channels formed in a rail, or as a channel provided in each of a pair rail members that have been fastened to the other to form a rail. In such arrangements the grid opening and a track-width on each side defines the “grid cell”. In arrangements where one direction of rails has only a single track, the grid cell may extend a full rail-width on those sides.

[0098] In an embodiment of the automated storage and retrieval system, the footprint of the second section of the container handling vehicle may be about the size of a grid cell of the rail system, and the first section and the third section may have a footprint less than the area of half a grid cell. I.e. the first section and the third section may extend less than 50 percent into the neighboring grid cell.

[0099] A method of assembling a container handling vehicle is described. The container handling vehicle may be formed of different modules that, when assembled, form the first section, second section and the third section.

[00100] It is also described a method of assembling a container handling vehicle according as defined above, the method comprising the steps of: assembling the first section of the vehicle frame, the first section comprising:

- the first wheel and the second wheel of the first set of wheels,

- the first drive motor,

- the first wheel link 8’ and the second wheel link of the first pair of wheel links,

- the first wheel and the fourth wheel of the second set of wheels; assembling the third section of the vehicle frame, the third section comprising:

- the third wheel and the fourth wheel of the first set of wheels,

- the second drive motor,

- the first wheel link and the second wheel link of the second pair of wheel links,

- the second wheel and the third wheel of the second set of wheels; connecting the second section of the vehicle frame to the first section of the vehicle frame and the third section of the vehicle frame; interconnecting the first wheel link of the first pair of wheel links to the first wheel link of the second pair of wheel links by the single coupler link system.

[00101] In the present specification the term “storage container” is intended to mean any goods holder unit having a bottom and side portions suitable for releasable connection to the container handling vehicle’s lifting device, and may be in the form of, for example, a bin, a tote, a tray or similar. The side portions may preferably comprise gripping recesses. The side portions are preferably sidewalls. The height of the sidewalls may vary depending on the intended use of the automated storage and retrieval system and the goods to be stored. Gripping recesses may be arranged at an upper rim of the sidewalls. The outer horizontal periphery of the storage container is preferably rectangular. [00102] The relative terms “upper”, “lower”, “below”, “above”, “higher” etc. shall be understood in their normal sense and as seen in a cartesian coordinate system.

[00103] The invention maybe used in connection with storage containers and systems as described above. However, other areas where the disclosed automated storage and retrieval system and methods may be used is within vertical farming, micro-fulfilment or grocery/e-grocery.

BRIEF DESCRIPTION OF THE DRAWINGS

[00104] Following drawings are appended to facilitate the understanding of the invention. The drawings show embodiments of the invention, which will now be described by way of example only, where:

[00105] Fig. 1 is a perspective view of a frame structure of a prior art automated storage and retrieval system;

[00106] Fig. 2 is a perspective view of a prior art container handling vehicle having an internally arranged cavity for carrying storage containers therein;

[00107] Fig. 3 is a perspective view of a prior art container handling vehicle having a cantilever for carrying storage containers underneath;

[00108] Fig. 4 is a perspective view, seen from below, of a prior art container handling vehicle having an internally arranged cavity for carrying storage containers therein;

[00109] Fig. 5 is a perspective view of the container handling vehicle in Fig. 4 without side and top panels;

[00110] Figs. 6A and 6B show different perspective views of a container handling vehicle operating on a rail system of an automated storage and retrieval system;

[00111] Fig.yA is an exploded view of the container handling vehicle of Figs. 6A and 6B without side and top panels showing a first embodiment of a coupler link system of a container handling vehicle;

[00112] Fig. 7B shows a container handling vehicle where a single coupler link system and a first wheel and a fourth wheel of the first set of wheels have been removed to better illustrate the components behind said parts; [00113] Fig. 7C is a perspective view of a wheel lift assembly of the container handling vehicle;

[00114] Fig. 7D is a side perspective view of the container handling vehicle showing a first lifting device motor in a first section of the container handling vehicle;

[00115] Fig. 8A is a top view of the container handling vehicle of Figs. 6A and 6B showing first, second and third sections of the container handling vehicle;

[00116] Fig. 8B shows footprints of the respective first, second and third sections of the container handling vehicle;

[00117] Figs. 9A-9C are different views of the container handling vehicle of Figs. 6-8 with the wheels connected to the wheel lift mechanism in the tracks of the rail system;

[00118] Fig. 10 is an exploded view of a vehicle frame of the container handling vehicle of Figs. 6-9.

[00119] Fig. nA is a side perspective view of a second embodiment of a coupler link system of a container handling vehicle;

[00120] Fig. 11B is an enlarged view of section A in Fig. nA;

[00121] Fig. 11C is an enlarged view of section B in Fig. 11B;

[00122] Fig. 11D shows details of section B in Fig. 11B from another view;

[00123] Fig. 11E shows the frame 10 of a container handling vehicle 501 for mounting of the coupler link system 14-1,14-2,14-3 according to the second embodiment with the other components removed.

DETAILED DESCRIPTION OF THE INVENTION

[00124] In overview, a container handling vehicle (501) comprises: a vehicle frame (10); a first set of wheels for driving in a first direction (X); and a second set of wheels for driving in a second direction (Y). The vehicle frame (10) defines a first section (Si), a second section (S2) and a third section (S3) of the container handling vehicle arranged side-by-side, wherein the second section (S2) comprises a cavity (26) for accommodating a storage container (106), and wherein the first section (Si) is arranged on a first side of the second section (S2) and the third section (S3) is arranged on an opposite second side of the second section (S2). The first set of wheels (11) are arranged to be movable in a vertical direction (Z) relative to the vehicle frame (10) between an upper position in which the second set of wheels (12) allows movement of the container handling vehicle (501) along the second direction (Y), and a lower position in which the first set of wheels (11) allows movement of the container handling vehicle (501) along the first direction (X). A single coupler link system (14’;14-

1.14-2,14-3) is arranged to couple the first wheel (11a) and second wheel (11b) of the first set of wheels to the third wheel (11c) and fourth wheel (nd) of the first set of wheels to enable the wheels of the first wheel set to move together in the vertical direction (Z) relative to the frame. The coupler link system (14’; 14-1,14-

2.14-3) maybe arranged on one side of the container handling vehicle only.

[00125] In the following, embodiments of the invention will be discussed in more detail with reference to the appended drawings. It should be understood, however, that the drawings are not intended to limit the invention to the subject-matter depicted in the drawings.

[00126] A frame structure 100 of the automated storage and retrieval system 1 maybe constructed in a similar manner to the prior art frame structure 100 described above in connection with Figs. 1. That is, the frame structure 100 may comprise a number of upright members 102, and comprise a first, upper rail system 108 extending in the X direction and Y direction.

[00127] The frame structure 100 may comprise storage compartments in the form of storage columns 105 provided between the members 102 wherein storage containers 106 maybe stackable in stacks 107 within the storage columns 105.

[00128] The frame structure 100 can be of any size. In particular, it is understood that the frame structure can be considerably wider and/or longer and/or deeper than disclosed in Fig. 1. For example, the frame structure 100 may have a horizontal extent of more than 700x700 columns and a storage depth of more than twelve containers.

[00129] The prior art container handling vehicles comprising a cavity for accommodating a storage container, see figs. 2, 4 and 5, have certain advantageous features. In particular, the guidance/support provided to a storage container when accommodated in the cavity entails that the vehicles may have increased acceleration/retardation relative to the cantilevered container handling vehicle 301 shown in fig. 3. However, the potential increase in acceleration/ retardation is not fully realized due to instability of the vehicles. The instability is caused by both vehicles 201,401 having many of the drive, power, control and lifting components arranged above the cavity, providing a high centre of gravity.

[00130] The vehicle body of the container handling vehicle in Figs. 4 and 5 comprises a first section Si and a second section S2 arranged side by side. The configuration of having a first section Si and a second section S2 is disclosed in PCT/EP2018/077732. Due to the increased footprint relative to the footprint of the vehicle in Fig. 2, the stability is slightly improved. However, as shown in Fig, 5, the prior art container handling vehicle 401 features at least a control unit 19, a replaceable battery 18 and wheel lifting components, including a wheel lift shaft 17, arranged above the cavity 26. The wheel lift shaft 17 extends above the cavity interconnecting two opposite wheel lift plates 21a, 21b. It is noted that the drive motors of the container handling vehicle 401 are not arranged above the cavity. The positioning of the drive motors is made possible by use of wheel hub motors 38. An advantage of using wheel hub motors is that all wheels of the container handling vehicle may be driven wheels providing increased traction of the wheels.

[00131] Disadvantages of using multiple wheel hub motors is the relatively high cost and potentially increased service/maintenance. In addition, at least for the prior art container handling vehicle in Fig. 2, the power and torque that may be provided by the wheel hub motors are restricted since they must have a size allowing them to fit within the vehicle without extending into the cavity of the first section or obstructing each other in the second section.

[00132] The present invention provides a container handling vehicle having improved stability and traction of the drive wheels. Further advantages of the container handling vehicle 501 described below includes lower service costs and the potential for improved manufacturing and reduced assembling time of the container handling vehicle 501.

First embodiment of a coupler link system - Figures 6-10

[00133] Figs. 6A and 6B show different perspective views of a container handling vehicle 501 operating on a rail system of an automated storage and retrieval system. [00134] The container handling vehicle 501 is suitable for use in prior art storage systems as discussed in the background section and shown in Fig. 1 and discussion in relation to those systems above can apply also to the improved container handling vehicle described herein.

[00135] Fig.yA is an exploded view of the container handling vehicle 501 of Figs. 6A and 6B without side and top panels.

[00136] The container handling vehicle 501 features a vehicle frame 10 defining a first section Si, a second section S2 and a third section S3 of the container handling vehicle 501 arranged side-by-side. The first section Si is arranged on a first side of the second section S2 and the third section is arranged on an opposite second side of the second section S2.

[00137] The second section S2 comprises a lifting device 15 for lifting a storage container 106, and provides a cavity 26 in which the storage container 106 (storage container 106 not shown in Fig. 7 A) may be accommodated. The lifting device 15 has a lifting frame 16 and two rotatable lifting shafts 33 configured to raise and lower the lifting frame 16 via a set of lifting bands 5. A first lifting device motor 28a for driving the lifting device 15, i.e. rotating the lifting shafts 33, is arranged in the first section Si.

[00138] The container handling vehicle 501 comprises a first set of wheels 11 and a second set of wheels 12 configured to move the container handling vehicle 501 upon on a rail system 108 (not shown in Fig. 7 A, see e.g. Fig. 1). The rail system 108 (see Fig. 1) comprises a first set of parallel rails no and a second set of parallel rails 111 arranged perpendicular to the first set of rails no. The rail system 108 is arranged in a horizontal, grid-based manner.

[00139] The first set of wheels 11 comprises a first wheel 11a, a second wheel 11b, a third wheel 11c and a fourth wheel nd for driving in the first direction X. The first wheel 11a and the second wheel 11b of the first set of wheels 11 are arranged on opposite portions of the first section Si. A first drive motor 20a for driving the first wheel 11a and the second wheel 11b of the first set of wheels 11 is arranged in the first section Si. A first drive shaft 22a is rotatably connected to the first drive motor 20a and extends between the two opposing ends of the first section Si where the first wheel 11a and the second wheel 11b of the first set of wheels 11 are arranged. Drive bands 23 (only one drive band shown in Fig. 7 A) extends between the first drive shaft 22a and the respective first wheel 11a and second wheel 11b of the first set of wheels such that rotation of the first drive motor 20a is transferred to the first wheel na and the second wheel nb via the first drive shaft 22a and the drive bands 23.

[00140] The third wheel 11c and the fourth wheel nd of the first set of wheels 11 are arranged on opposite portions of the third section S3. A second drive motor 20b for driving the third wheel 11c and the fourth wheel nd of the first set of wheels 11 is arranged in the third section S3. Similar to the setup in the first section Si, a second drive shaft 22b is rotatably connected to the second drive motor 20b and extends between the two opposing ends of the third section S3 where the third wheel 11c and the fourth wheel nd of the first set of wheels 11 are arranged. Drive bands 24 (only one drive band shown in Fig. 7 A) extends between the second drive shaft 22b and the respective third wheel 11c and fourth wheel nd of the first set of wheels such that rotation of the second drive motor 20b is transferred to the third wheel 11c and the fourth wheel nd via the first drive shaft 22b and the drive bands 24.

[00141] All of the wheels 11a, 11b, 11c, nd of the first set of wheels 11 are thus driven or motorized wheels.

[00142] The second set of wheels 12 comprises a first wheel 12a, a second wheel 12b (not shown in Fig. 7 A, see e.g. Fig. 8A), a third wheel 12c (not shown in Fig. 7 A, see e.g. Fig. 8A) and a fourth wheel I2d for driving in the second direction Y. The first wheel 12a and the fourth wheel I2d are arranged on one side of the second section S2 and the second wheel 12b and the third wheel 12c are arranged on an opposite side of the second section S2. The first wheel 12a and the fourth wheel i2d are arranged in a common vertical plane such that they are mutually arranged to drive in the same underlying track Similarly, the second wheel 12b and the third wheel 12c are arranged in a common vertical plane such that they are mutually arranged to drive in the same underlying track.

[00143] To allow a change of direction in which the container handling vehicle 501 travels upon the rail system 108, the first set of wheels 11 is arranged to be moveable in a vertical direction Z relative to the vehicle frame 10. The first set of wheels 11 may move between an upper position, in which the second set of wheels 12 allows movement of the container handling vehicle 501 along the second direction Y, and a lower position, in which the first set of wheels 11 allows movement of the container handling vehicle 501 along the first direction X. [00144] The vertical movement of the first set of wheels 11 is obtained by a wheel lift mechanism featuring pivotable first and second pairs of wheel links 8,9 connected by a coupler link system 14’ and driven by an actuator assembly 6,7. The first pair of wheel links 9 comprises a first wheel link 8’ and a second wheel link 8”. Similarly, the second pair of wheel links 9 comprises a first wheel link 9’ and a second wheel link 9”. The coupler link system 14’ is arranged on one side of the container handling vehicle 501 only.

[00145] In the wheel lift mechanism, the fourth wheel nd of the first set of wheels 11 is mounted to the corresponding wheel link 8” of the first pair of wheel links 8 and the third wheel 11c of the first set of wheels 11 is mounted to the corresponding second wheel link 9” of the first pair of wheel links 8. The first and second wheel links 8’, 8” of the first pair of wheel links 8 comprising a first pivot coupling 3 and a second pivot coupling 4. The first and second wheel links 8’, 8” of the first pair of wheel links 8 are pivotably connected to the vehicle frame 10 by the respective first pivot couplings 3.

[00146] Similarly, each of the first wheel 11a and the second wheel 11b of the first set of wheels 11 is mounted to a corresponding first and second wheel link 9’, 9” of the second pair of wheel links 9 comprising a third pivot coupling 29 and a fourth pivot coupling 30. The first and second wheel links 9’, 9” of the second pair of wheel links 9 are pivotably connected to the vehicle frame 10 by the respective third pivot coupling 29.

[00147] The first wheel link 9’ of the second pair of wheel link 9 supporting the first wheel 11a of the first set of wheels 11 and the first wheel link 8’ of the first pair of wheel links 8 supporting the fourth wheel nd of the first set of wheels are connected via the respective second and fourth pivot couplings 4,30 by a single coupler link system 14’.

[00148] The single coupler link system 14’ may be plate-shaped or bar-shaped as shown, and function as both force or movement transferring element between the first wheel link 8’ of the first pair of wheel links 8 and the first wheel link of the second pair of wheel links 9, and as bodywork closing off (or at least providing a barrier for) two lower sides of the vehicle. The dual function of the coupler link system 14’ provides a cost efficient, lightweight and simple mechanical solution.

[00149] The first section Si comprises a first cross-member 13a connected to both the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9. The first cross-member 13a is configured to fix the angular position of the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 relative to each other, such that the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 will move in unison around their respective third pivot coupling 29.

[00150] Similarly, the third section S3 comprises a second cross-member 13b connected to both the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8. The second cross-member 13b is configured to fix the angular position of the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 relative to each other, such that the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 will move in unison around their respective first pivot coupling 3.

[00151] The actuator assembly is arranged in the third section S3 and features a wheel lift motor 6 and an actuator link 7. The actuator link 7 is connected to the first wheel link 8’ of the pair of first wheel links 8 by a fifth pivot coupling 27. The actuator assembly is configured to move the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 around the respective first pivot couplings 3 between a first angular position and a second angular position. The movement of the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 is transferred to the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 via the single coupler link system 14’, such that the first set of wheels 11 is in the upper position, see Figs. 7A-7C, or the lower position, see Figs. 9A-9B, when the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 are in the first angular position and the second angular position, respectively. I.e. the single coupler link system 14’ (i.e. the one disclosed plate element with reference number 14’) is the only connection between the first pair of wheel links 8 and the second pair of wheel links 9. The movement direction of the first pair of wheel links 8 and the second pair of wheel links 9 when moving the first set of wheels 11 to the upper position are indicated by arrows R-8 and R-9 in Fig. 7C

[00152] The single coupler link system 14’ is configured to move in the first direction X towards the first wheel 11a and the second wheel 11b of the first set of wheels 11, respectively, when the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 are moved from the second angular position to the first angular position, and configured to move in the first direction X towards the third wheel 11c and the fourth wheel nd of the first set of wheels 11, respectively, when the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 are moved from the first angular position to the second angular position.

[00153] Each of the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 comprises a first edge section 37a (see Fig 9B) extending upwards from the level of the third pivot coupling 29 and a second edge section 37b (see Fig. 9B) extending downwards from the level of the third pivot coupling 29. The first edge section 37a and the second edge section 37b face away from the connected first wheel link 8’ and second wheel link 8” of the first pair of wheel link 8 and are inclined relative to each other such that the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 does not extend beyond an outer side of the vehicle frame 10 when moved around the third pivot coupling 29.

[00154] The second drive shaft 22b and the second cross-member 13b are configured to move in parallel when the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 are moved between the first and second angular position. The second drive shaft 22b and the second cross-member 13b are configured to move in unison with the first wheel link 9\ and the second wheel link 9” of the first pair of wheel links 9 between the first and second angular position.

[00155] Similarly, the first drive shaft 22a and the first cross-member 13a are configured to move in parallel when the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 are moved between the first and second angular position. The first drive shaft 22a and the first cross-member 13a are configured to move in unison with the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 between the first and second angular position.

[00156] By moving the first drive shaft 22a, the second drive shaft 22b, the first cross-member 13a and the second cross-member 13b in unison with the respective first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9 and the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8, both excessive wear of the drive bands 23,24 due to stretching, and service involving tightening of the drive bands 23,24, are minimized. In this way, the relative mounting positions of the wheels and their respective drive motors can remain fixed during the angular motion of the first and second pair of wheel links 8,9, such that belt tension in the drive bands 23,24 remains constant during raising and lowering of the first set of wheels 11.

[00157] In a first embodiment, the single coupler link system 14’ is configured to move in the first direction towards the first wheel 11a and the second wheel 11b of the first set of wheels 11, respectively, when the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8 are moved from the second angular position to the first angular position. I.e. both the first pair of wheel links 8 and the second pair of wheel links 9 rotate in the same direction when moving the first set of wheels 11 in the Z direction.

[00158] Fig. 7D is a side perspective view of the container handling vehicle 501 showing a second lifting device motor 28b in the third section S3 of the container handling vehicle 501.

[00159] Fig. 8A is a top view of the container handling vehicle of Figs. 6A and 6B showing first, second and third sections Si, 82,83 of the container handling vehicle 501. As disclosed, the container handling vehicle 501 may comprise a third drive motor 20c for driving the first wheel 12a and the fourth wheel I2d of the second set of wheels 12. The third drive motor 20c is arranged in the first section Si. The third drive motor 20c may drive the connected first wheel 12a and fourth wheel i2d of the second set of wheels 12 via a drive band 34.

[00160] Further referring to Fig. 8A, the container handling vehicle 501 may comprise a fourth drive motor 2od for driving the second wheel 12b and the third wheel 12c of the second set of wheels 12. The fourth drive motor 2od is arranged in the third section S3. The fourth drive motor 2od may drive the connected second wheel 12b and third wheel 12c of the second set of wheels 12 via a drive band 35.

[00161] Power to drive the motors of the container handling vehicle is provided by a rechargeable battery 31 (and/or high power capacitors) arranged in the third section S3. The rechargeable battery 31 is connected to a set of electrodes 32. The electrodes 32 are configured to receive power from a charging station. The two electrodes 32 are arranged on opposite sides of a vertical centre plane of the container handling vehicle, the vertical centre plane extending in the first direction X. An advantageous effect of having the electrodes 32 separated in this manner is that lateral skewing of the container handling vehicle relative to the first direction X during initial connection to a charging station is minimized. A suitable charging station is disclosed in e.g. PCT/EP2021/074340.

[00162] A control unit 19 for controlling at least the drive components (i.e. the first, second, third and fourth drive motors 20a, 20b, 20c, 2od, the wheel lift motor 6 and the first and second lifting device motors 28a, 28b) is arranged in the third section S3.

[00163] A set of replaceable distance pins 25 are arranged above the lifting frame 16. The distance pins 25 are configured to interact with switches (not shown) on an upper portion of the lifting frame 16 when the lifting frame 16 is in an upper position. The distance pins help to stabilize a shallower container 106 in the cavity (and they can then be removed when the vehicle is being used with larger containers).

[00164] The distance pins 25 ensure that the efficiency of the container handling vehicle 501 maybe optimized with respect to the height of the storage containers 106 being lifted. If the container handling vehicle 501 is to be used for higher storage containers, shorter distance pins 25 may be installed to ensure that the containers are not lifted higher than required for entering the cavity 26.

[00165] In alternative embodiments, the distance pins 25 may be adjustable, i.e. have an adjustable height, instead of being replaceable. Adjustable distance pins may for instance be obtained by having telescopic or foldable distance pins.

[00166] Each of the container handling vehicles 501 comprise four of the distance pins 25 arranged to interact with the lifting frame 16 at four corner sections. The distance pins 25 may also be configured to stabilize the lifting frame 16, and any storage container 106 connected thereto, when the lifting frame 16 is in an upper position.

[00167] The configuration of the container handling vehicle 501 allows for a highly efficient method of assembly since the first section Si, the third section S3, and a major part of the components making up the vehicle may constitute a preassembled vehicle module. The method of assembling may comprise the steps of: assembling the first section Si of the vehicle frame 10, the first section Si comprising: o the first wheel na and the second wheel nb of the first set of wheels n, o the first drive motor 20a, o the first wheel link 8’ and the second wheel link 8” of the first pair of wheel links 8, o the first wheel 12a and the fourth wheel i2d of the second set of wheels 12;

- assembling the third section S3 of the vehicle frame 10, the third section S3 comprising: o the third wheel 11c and the fourth wheel nd of the first set of wheels 11, o the second drive motor 20b, o the first wheel link 9’ and the second wheel link 9” of the second pair of wheel links 9, o the second wheel 12b and the third wheel 12c of the second set of wheels 12;

- connecting the second section S2 of the vehicle frame 10 to the first section Si of the vehicle frame 10 and the third section S3 of the vehicle frame 10;

- interconnecting the first wheel link 8’ of the first pair of wheel links 8 to the first wheel link 9’ of the second pair of wheel links 9 by the single coupler link system 14’.

[00168] Figs. 9A-9C are different views of the container handling vehicle of Figs. 6-8 with the wheels connected to the wheel lift mechanism in the tracks of the rail system. In the illustrated embodiment - the first direction (x direction) is a smaller dimension of the grid cell 130 as compared to the second direction (y direction). The extension of the container handling vehicle 501 is preferable less than two cells in the first direction (i.e. the x direction). This ensures that the container handling vehicle 501 is relatively compact and proportional in the first direction (x direction) and the second direction (y direction). [00169] Fig. 10 is an exploded view of a vehicle frame 10 of the container handling vehicle of Figs. 6-9. As shown, the vehicle frame 10 comprises a first vertical subframe 40 forming part of the first section Si and a second vertical subframe 41 forming part of the third section S3. The container handling vehicle 501 also comprises a horizontal upper member 42 forming part of the second section S2. The horizontal upper member 42 is configured to be arranged above the cavity 26 (cavity 26 not shown in Fig. 10, see e.g. Fig. 7A.

[00170] The horizontal upper member 42 is connectable to the first vertical subframe 40 and the second vertical subframe 41. The first and second vertical subframes 40,41 are configured to be arranged on opposite sides of the cavity 26.

[00171] The vehicle frame 10 is further disclosed with side cross-members 43 configured to be arranged on opposite sides of the cavity 26. The side crossmembers 43 may be horizontal members connected to lower portions of the first and second vertical subframes 40,41.

Second embodiment of coupler link system - Figures 11A-11E

[00172] A second embodiment of the coupler link system 14-1,14-2,14-3 will be described with reference to Figures 11A-11E.

[00173] Fig. nA is a side perspective view of a second embodiment of a coupler link system 14-1,14-2,14-3 of a container handling vehicle 501

[00174] Fig. 11B is an enlarged view of section A in Fig. nA.

[00175] Fig. 11C is an enlarged view of section B in Fig. 11B.

[00176] Fig. 11D shows details of section B in Fig. 11B from another view.

[00177] Fig. 11E shows the frame 10 of a container handling vehicle 501 for mounting of the coupler link system 14-1,14-2,14-3 according to the second embodiment with the other components removed.

[00178] Most of the components of the container handling vehicle 501 described in relation to the container handling vehicle in Figs. 6-10 are identical or at least similar and will not be repeated herein. However, the coupler link system 14’ and actuator link 7 in Figs. 6-10 have been replaced by a first coupler link 14-1, a second coupler link 14-2 and a rotatable plate 14-3. Similar to the first embodiment of the coupler link system in Figs. 6-10, the coupler link system 14-1,14-2,14-3 in the second embodiment in Figs. 11A-11E is arranged on one side of a container handling vehicle 501 only. In addition, each first and second wheel links 8’, 8” of the first pair of wheel links 8 comprises a first pivot coupling 3 (only the first pivot coupling 3 of the first wheel link 8’ of the first pair of wheel links 8 shown in the Figures) and is pivotably connected to the vehicle frame 10 by the first pivot coupling 3. Similarly, each of the first and second wheel link 9’, 9” of the second pair of wheel links 9 comprises a third pivot coupling 29 (only the third pivot coupling 29 of the first wheel link 9’ of the second pair of wheel links 9 shown in the Figures) and is pivotably connected to the vehicle frame 10 by the third pivot coupling 29.

[00179] The coupler link system 14-1,14-2,14-3 features a rotatable plate 14-3 rotatably connectable to a rotational shaft 6’ of a wheel lift motor 6. A first coupler link 14-1 is connectable between the first wheel link 9’ of the second pair of wheel links 9 and the rotatable plate 14-3. A second coupler link 14-2 is connectable between the first wheel link 8’ of the first pair of wheel links and the rotatable plate 14-3.

[00180] The first wheel link 8’ of the first pair of wheel links 8 comprises a second pivot coupling 4 rotatably connecting the first wheel link 8’ of the first pair of wheel links 8 to the second coupler link 14-2.

[00181] The first wheel link 9’ of the second pair of wheel links 9 comprises a fourth pivot coupling 30 rotatably connecting the first wheel link 9’ of the second pair of wheel links 9 to the first coupler link 14-1.

[00182] Arrow R-8 shows the rotation direction of the first pair of wheel links 8, whereas arrow R-9 shows the rotation direction of the second pair of wheel links 9, respectively. As indicated by the arrows R-8, R-9 in Fig nA the first pair of wheel links 8 and the second pair of wheel links 9 move, i.e. rotate, in opposite directions around their respective first pivot coupling 3 and third pivot coupling 29. I.e. the first pair of wheel links 8 and the second pair of wheel links 9 rotate in opposite directions when moving the first set of wheels 11 in the Z direction.

[00183] In the preceding description, various aspects of the independent claims have been described. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the system and its workings. However, this description is not intended to be construed in a limiting sense. Various modifications and variations of the illustrative embodiment, as well as other embodiments of the system, which are apparent to persons skilled in the art to which the disclosed subject matter pertains, are deemed to lie within the scope of the present invention as defined in the attached claims.

[00184] Aspects and features of the present invention are defined in the following numbered clauses.

Clauses

1. A container handling vehicle (501) for operation on an automated storage and retrieval system (1), the automated storage and retrieval system (1) comprising a two-dimensional rail system (108) comprising a first set of parallel rails (110) in a horizontal plane PH) arranged to guide movement of container handling vehicles (201,301,401) in a first direction (X) across the top of a frame structure (100), and a second set of parallel rails (111) in the horizontal plane PH) arranged perpendicular to the first set of parallel rails (110) to guide movement of the container handling vehicles (201,301,401) in a second direction (Y) which is perpendicular to the first direction (X), the container handling vehicle comprises:

- a vehicle frame (10) defining a first section (Si), a second section (S2) and a third section (S3) of the container handling vehicle arranged side-by-side, wherein the first section (Si) is arranged on a first side of the second section (S2) and the third section (S3) is arranged on an opposite second side of the second section (S2);

- the second section (S2) comprises a cavity (26) for accommodating a storage container (106);

- a first set of wheels (11) comprising a first wheel (11a), a second wheel (11b), a third wheel (11c) and a fourth wheel (nd) for driving in the first direction (X);

- a second set of wheels (12) comprising a first wheel (12a), a second wheel (12b), a third wheel (12c) and a fourth wheel (i2d) for driving in the second direction (Y);

- a first drive motor (20a) for driving the first wheel (11a) and the second wheel (11b) of the first set of wheels (11);

- a second drive motor (20b) for driving the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11); and wherein the first wheel (11a) and the second wheel (11b) of the first set of wheels (11) and the first drive motor (20a) are arranged in the first section (Si), and the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11) and the second drive motor (20b) are arranged in the third section (S3);

- wherein the first set of wheels (11) being arranged to be movable in a vertical direction (Z) relative to the vehicle frame (10) between an upper position in which the second set of wheels (12) allows movement of the container handling vehicle (501) along the second direction (Y), and a lower position in which the first set of wheels (11) allows movement of the container handling vehicle (501) along the first direction (X); and wherein:

- the third wheel (11c) of the first set of wheels (11) is mounted to a first wheel link (8’) of a first pair of wheel links (8) and the fourth wheel (nd) of the first set of wheels (11) is mounted to a second wheel link (8”) of the first pair of wheel links (8), each first and second wheel links (8’, 8”) of the first pair of wheel links (8) comprises a first pivot coupling (3) and the first wheel link (8’) of the first pair of wheel links (8) comprises a second pivot coupling (4) and each of the first and second wheel links (8’, 8”) of the first pair of wheel links (8) is pivotably connected to the vehicle frame (10) by the first pivot coupling (3);

- the first wheel (11a) of the first set of wheels (11) is mounted to a first wheel link (9’) of a second pair of wheel links (9) and the second wheel (11b) of the first set of wheels (11) is mounted to a second wheel link (9”) of the second pair of wheel links (9), each of the first and second wheel link (9’, 9”) of the second pair of wheel links (9) comprises a third pivot coupling (29) and the first wheel link (9’) of the second pair of wheel links (9) comprises a fourth pivot coupling (30) and each first and second wheel links (9’, 9”) of the second pair of wheel links (9) is pivotably connected to the vehicle frame (10) by the third pivot coupling (29);

- the first section (Si) comprises a first cross-member (13a) fixing the angular position of the first and second wheel links (9 ’,9”) of the second pair of wheel links (9) relative to each other, such that the first and second wheel links (9’, 9”) of the second pair of wheel links (9) will move in unison around their respective third pivot coupling (29); and - the third section (S3) comprises a second cross-member (13b) fixing the angular position of the first and second wheel links

(8’, 8”) of the first pair of wheel links (8) relative to each other, such that the first and second wheel links (8’, 8”) of the first pair of wheel links (8) will move in unison around their respective first pivot coupling (3);

- the first wheel link (8’) of the first pair of wheel links (8) and the first wheel link (9’) of the second pair of wheel links (9) are connected via the respective second and fourth pivot couplings (4,30) by a single coupler link system (14’;14-1, 14-2, 14-3). The container handling vehicle (501) according to clause 1, comprising a third drive motor (20c) for driving the first wheel (12a) and the fourth wheel (i2d) of the second set of wheels (12), and wherein the third drive motor (20c) is arranged in the first section (Si). The container handling vehicle (501) according to clause 2, comprising a fourth drive motor (2od) for driving the second wheel (12b) and the third wheel (12c) of the second set of wheels (12), and wherein the fourth drive motor (2od) is arranged in the third section (S3). The container handling vehicle (501) according to any of the preceding clauses, wherein the container handling vehicle comprises a first lifting device motor (28a), and wherein the first lifting device motor (28a) is arranged in the first section (Si). The container handling vehicle (501) according to clause 4, wherein the container handling vehicle comprises a second lifting device motor (28b), and wherein the second lifting device motor (28b) is arranged in the third section (S3). The container handling vehicle (501) according to any of the preceding clauses, wherein the second section provides a cavity (26) in which a storage container (106) maybe accommodated, and the container handling vehicle (501) comprises a lifting device (15) in the second section (S2) for lifting and lowering of the storage container (106) into the cavity (26), and wherein the first wheel (12a) and the fourth wheel (i2d) of the second set of wheels (12) are arranged on a first side of the cavity (26) and the second wheel (12b) and the third wheel (12c) of the second set of wheels (12) are arranged on an opposite second side of the cavity (26). The container handling vehicle (501) according to any of the preceding clauses, wherein the first section (Si) has a footprint (Fl), the second section (S2) has a footprint (F2), and wherein a size ratio of the footprint (F2) of the second section (S2) relative to the footprint (Fl) of the first section (Si) is at least 2:1. The container handling vehicle (501) according to any of the preceding clauses, wherein the third section (S3) has a footprint (F3), and wherein a size ratio of the footprint (F2) of the second section relative to the footprint (F3) of the third section (S3) is at least 2:1. The container handling vehicle (501) according to any of the preceding clauses, wherein the third section (S3) comprises an actuator assembly (6,7), the actuator assembly (6,7) being arranged to move the first and second wheel links (8’, 8”) of the first pair of wheel links (8) around the respective first pivot couplings (3) between a first angular position and a second angular position, the movement of the first and second wheel links (8’, 8”) of the first pair of wheel links (8) being transferred to the first and second wheel links (9’, 9”) of the second pair of wheel links (9) via the single coupler link system (14’) and the first cross-member (13a) and the second cross-member (13b), such that the first set of wheels (11) are in the upper position or the lower position when the first and second wheel links (8’, 8”) of the first pair of wheel links (8) are in the first angular position or the second angular position, respectively. The container handling vehicle (501) according to clause 9, wherein the single coupler link system (14’) is configured to move in the first direction (X) towards the first wheel (11a) and the second wheel (11b) of the first set of wheels (11), respectively, when the first and second wheel links (8’, 8”) of the first pair of wheel links (8) are moved from the second angular position to the first angular position. The container handling vehicle (501) according to clause 10, wherein the actuator assembly (6,7) is operatively connected to a wheel lift mechanism and is arranged to move the first wheel link (8’) and the second wheel link (8”) of the first pair of wheel links (8) around its first pivot coupling (3) between the first angular position and the second angular position. The container handling vehicle (501) according to any of clauses 9-11, wherein the actuator assembly comprises a wheel lift motor (6) or a linear actuator. The container handling vehicle (501) according to any of clauses 9-12, wherein the first wheel link (8’) of the first pair of wheel links (8) comprises a fifth pivot coupling (27) connected to the actuator assembly (6,7). The container handling vehicle (501) according to any of clauses 9-13, wherein the actuator assembly comprises an actuator link (7) pivotably connected to the first wheel link (8’) of the first pair of wheel links (8) to drive rotation of the first wheel link (8’) and the second wheel link (8”) of the first pair of wheel links (8). The container handling vehicle (501) according to any of the preceding clauses 9-14, wherein the first pair of wheel links (8) and the second pair of wheel links (9) move in the same direction around their respective first pivot coupling (3) and third pivot coupling (29). The container handling vehicle (501) according to any of the preceding clauses 1-8, wherein the coupler link system (14-1,14-2,14-3) comprises:

- a rotatable plate (14-3) rotatably connectable to a rotational shaft (6’) of a wheel lift motor (6);

- a first coupler link (14-1) connectable between the first wheel link (9’) of the second pair of wheel links and the rotatable plate (14-3);

- a second coupler link (14-2) connectable between the first wheel link (8’) of the first pair of wheel links and the rotatable plate (14-3). The container handling vehicle (501) according to clause 16, wherein the second pivot coupling (4) is configured to rotatably connect the first wheel link (8’) of the first pair of wheel links (8) to the second coupler link (14- 2) and the fourth pivot coupling (30) is configured to rotatably connect the first wheel link (9’) of the second pair of wheel links (9) to the first coupler link (14-1). The container handling vehicle (501) according to clause 16 or 17, wherein the first pair of wheel links (8) and the second pair of wheel links (9) move in opposite directions around their respective first pivot coupling (3) and third pivot coupling (29). - The container handling vehicle (501) according to any of the preceding clauses, comprising:

- a first drive shaft (22a) arranged in the first section (Si) and interconnecting the first and second wheel links (9 ’,9”) of the second pair of wheel links (9), wherein the first drive shaft (22a) is operatively connected to drive the first wheel (11a) and the second wheel (11b) of the first set of wheels (11); and

- a second drive shaft (22b) arranged in the third section (S3) and interconnecting the first and second wheel links (8’, 8”) of the first pair of wheel links (8), wherein the second drive shaft (22b) is operatively connected to drive the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11). . The container handling vehicle (501) according to any of the preceding clauses, wherein the vehicle frame (10) comprises a first vertical subframe

(40) forming part of the first section (Si) and a second vertical subframe

(41) forming part of the third section (S3) and a horizontal upper member

(42) forming part of the second section (S2), and wherein the horizontal upper member (42) is arranged above the cavity (26). . The container handling vehicle (501) according to clause 20, wherein the horizontal upper member (42) is connected to the first vertical subframe (40) and the second vertical subframe (41). . The container handling vehicle (501) according to clause 20 or 21, wherein the vehicle frame (10) comprises side cross-members (43) arranged on opposite sides of the cavity (26). . An automated storage and retrieval system comprising a container handling vehicle (501) according to any of the preceding clauses, wherein the automated storage and retrieval system comprises a frame structure (100) having a plurality of storage columns (105) for accommodating vertical stacks of storage containers (106), the frame structure (100) having a rail system (108) upon which the container handling vehicle (501) may move in two perpendicular directions above the storage columns (105).

24-A method of assembling a container handling vehicle according to any of clauses 1-22, the method comprising the steps of:

- assembling the first section (Si) of the vehicle frame (10), the first section (Si) comprising: o the first wheel (11a) and the second wheel (11b) of the first set of wheels (11), o the first drive motor (20a), o the first wheel link 8’ and the second wheel link (8”) of the first pair of wheel links (8), o the first wheel (12a) and the fourth wheel (i2d) of the second set of wheels (12);

- assembling the third section (S3) of the vehicle frame (10), the third section comprising: o the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11), o the second drive motor (20b), o the first wheel link (9’) and the second wheel link (9”) of the second pair of wheel links (9), o the second wheel (12b) and the third wheel (12c) of the second set of wheels (12);

- connecting the second section (S2) of the vehicle frame (10) to the first section (Si) of the vehicle frame (10) and the third section (S3) of the vehicle frame (10); interconnecting the first wheel link (8’) of the first pair of wheel links (8) to the first wheel link (9’) of the second pair of wheel links (9) by the single coupler link system (14’;14-1, 14-2, 14-3). A container handling vehicle comprising a first section, a second section and a third section, wherein the first section is arranged on a first side of the second section and the third section is arranged on an opposite second side of the second section. A first drive motor is arranged in the first section and a second drive motor is arranged in the third section. A single coupler link system arranged on one side of the container handling vehicle only is used during rotation of a first and second pair of wheel links connected to a first set of wheels and a second set of wheels respectively.

LIST OF REFERENCE NUMBERS

Claims

1. A container handling vehicle (501) for an automated storage and retrieval system (1), the container handling vehicle (501) comprising: a vehicle frame (10); a first set of wheels for driving in a first direction (X); a second set of wheels for driving in a second direction (Y); wherein the vehicle frame (10) defines a first section (Si), a second section

(52) and a third section (S3) of the container handling vehicle arranged side-by- side, wherein the second section (S2) comprises a cavity (26) for accommodating a storage container (106), and wherein the first section (Si) is arranged on a first side of the second section (S2) and the third section (S3) is arranged on an opposite second side of the second section (S2); wherein the first set of wheels (11) comprises a first wheel (11a), a second wheel (11b), a third wheel (11c) and a fourth wheel (nd) for driving in the first direction (X), wherein the first wheel (11a) and the second wheel (11b) are arranged in the first section (Si) and linked by a first cross-member (13a), and the third wheel (11c) and the fourth wheel (nd) are arranged in the third section

(53) and linked by a second cross-member (13b); wherein the first set of wheels (11) are arranged to be movable in a vertical direction (Z) relative to the vehicle frame (10) between an upper position in which the second set of wheels (12) allows movement of the container handling vehicle (501) along the second direction (Y), and a lower position in which the first set of wheels (11) allows movement of the container handling vehicle (501) along the first direction (X); wherein a single coupler link system (14’;14-1, 14-2, 14-3) is arranged to couple the first wheel (11a) and second wheel (11b) to the third wheel (11c) and fourth wheel (nd) to enable the wheels of the first wheel set to move together in the vertical direction (Z) relative to the frame.

2. The container handling vehicle (501) of claim 1, wherein the automated storage and retrieval system (1) comprises a two-dimensional rail system (108) comprising a first set of parallel rails (no) in a horizontal plane PH) arranged to guide movement of container handling vehicles (201,301,401) in the first direction (X) across the top of a frame structure (100), and a second set of parallel rails (111) in the horizontal plane PH) arranged perpendicular to the first set of parallel rails (110) to guide movement of the container handling vehicles (201,301,401) in the second direction (Y).

3. The container handling vehicle (501) of claim 1 or claim 2, wherein the first direction (X) is perpendicular to the second direction (Y).

4. The container handling vehicle (501) of any preceding claim, comprising: a first drive motor (20a) for driving the first wheel (11a) and the second wheel (11b) of the first set of wheels (11); a second drive motor (20b) for driving the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11); wherein the first drive motor (20a) is arranged in the first section (Si), and the second drive motor (20b) is arranged in the third section (S3).

5. The container handling vehicle (501) according to any preceding claim, wherein the second set of wheels (12) comprises a first wheel (12a), a second wheel (12b), a third wheel (12c) and a fourth wheel (i2d) for driving in the second direction (Y), the container handling vehicle (501) comprising a third drive motor (20c) for driving the first wheel (12a) and the fourth wheel (i2d) of the second set of wheels (12), and wherein the third drive motor (20c) is arranged in the first section (Si).

6. The container handling vehicle (501) according to claim 5, comprising a fourth drive motor (2od) for driving the second wheel (12b) and the third wheel (12c) of the second set of wheels (12), and wherein the fourth drive motor (2od) is arranged in the third section (S3).

7. The container handling vehicle (501) according to any preceding claim, wherein the container handling vehicle comprises a first lifting device motor (28a), and wherein the first lifting device motor (28a) is arranged in the first section (Si).

8. The container handling vehicle (501) of claim 7, wherein the container handling vehicle comprises a second lifting device motor (28b), and wherein the second lifting device motor (28b) is arranged in the third section (S3).

9. The container handling vehicle (501) according to any preceding claim, wherein the second section provides a cavity (26) in which a storage container (106) maybe accommodated, and the container handling vehicle (501) comprises a lifting device (15) in the second section (S2) for lifting and lowering of the storage container (106) into the cavity (26), wherein the second set of wheels (12) comprises a first wheel (12a), a second wheel (12b), a third wheel (12c) and a fourth wheel (i2d) for driving in the second direction (Y), and wherein the first wheel (12a) and the fourth wheel (i2d) of the second set of wheels (12) are arranged on a first side of the cavity (26) and the second wheel (12b) and the third wheel (12c) of the second set of wheels (12) are arranged on an opposite second side of the cavity (26).

10. The container handling vehicle (501) according to any preceding claim, wherein the first section (Si) has a footprint (Fl), the second section (S2) has a footprint (F2), and wherein a size ratio of the footprint (F2) of the second section (S2) relative to the footprint (Fl) of the first section (Si) is at least 2:1.

11. The container handling vehicle (501) according to any preceding claim, wherein the third section (S3) has a footprint (F3), and wherein a size ratio of the footprint (F2) of the second section relative to the footprint (F3) of the third section (S3) is at least 2:1.

12. The container handling vehicle (501) of any preceding claim, wherein the third wheel (11c) of the first set of wheels (11) is mounted to a first wheel link (8’) of a first pair of wheel links (8) and the fourth wheel (nd) of the first set of wheels (11) is mounted to a second wheel link (8”) of the first pair of wheel links (8), each first and second wheel links (8’, 8”) of the first pair of wheel links (8) comprises a first pivot coupling (3) and the first wheel link (8’) of the first pair of wheel links (8) comprises a second pivot coupling (4) and each of the first and second wheel links (8’, 8”) of the first pair of wheel links (8) is pivotably connected to the vehicle frame (10) by the first pivot coupling (3); wherein the first wheel (11a) of the first set of wheels (11) is mounted to a first wheel link (9’) of a second pair of wheel links (9) and the second wheel (11b) of the first set of wheels (11) is mounted to a second wheel link (9”) of the second pair of wheel links (9), wherein each of the first and second wheel link (9’, 9”) of the second pair of wheel links (9) comprises a third pivot coupling (29) and the first wheel link (9’) of the second pair of wheel links (9) comprises a fourth pivot coupling (30) and each first and second wheel links (9’, 9”) of the second pair of wheel links (9) is pivotably connected to the vehicle frame (10) by the third pivot coupling (29); wherein the first section (Si) comprises the first cross-member (13a), wherein the first cross-member fixes the angular position of the first and second wheel links (9’, 9”) of the second pair of wheel links (9) relative to each other, such that the first and second wheel links (9’, 9”) of the second pair of wheel links (9) will move in unison around their respective third pivot coupling (29); and the third section (S3) comprises a second cross-member (13b), wherein the second cross-member fixes the angular position of the first and second wheel links (8’, 8”) of the first pair of wheel links (8) relative to each other, such that the first and second wheel links (8’, 8”) of the first pair of wheel links (8) will move in unison around their respective first pivot coupling (3); wherein the first wheel link (8’) of the first pair of wheel links (8) and the first wheel link (9’) of the second pair of wheel links (9) are connected via the respective second and fourth pivot couplings (4,30) by the single coupler link system (14’;14-1, 14-2, 14-3).

13. The container handling vehicle (501) according to claim 12, wherein the third section (S3) comprises an actuator assembly (6,7), the actuator assembly (6,7) being arranged to move the first and second wheel links (8’, 8”) of the first pair of wheel links (8) around the respective first pivot couplings (3) between a first angular position and a second angular position, the movement of the first and second wheel links (8’, 8”) of the first pair of wheel links (8) being transferred to the first and second wheel links (9 ’,9”) of the second pair of wheel links (9) via the single coupler link system (14’) and the first cross-member (13a) and the second cross-member (13b), such that the first set of wheels (11) are in the upper position or the lower position when the first and second wheel links (8’, 8”) of the first pair of wheel links (8) are in the first angular position or the second angular position, respectively.

14. The container handling vehicle (501) according to claim 12 or claim 13, wherein the single coupler link system (14’) is configured to move in the first direction (X) towards the first wheel (11a) and the second wheel (11b) of the first set of wheels (11), respectively, when the first and second wheel links (8’, 8”) of the first pair of wheel links (8) are moved from the second angular position to the first angular position.

15. The container handling vehicle (501) according to claim 14, wherein the actuator assembly (6,7) is operatively connected to a wheel lift mechanism and is arranged to move the first wheel link (8’) and the second wheel link (8”) of the first pair of wheel links (8) around its first pivot coupling (3) between the first angular position and the second angular position.

16. The container handling vehicle (501) according to any of claims 9 to 11, wherein the actuator assembly comprises a wheel lift motor (6) or a linear actuator.

17. The container handling vehicle (501) according to any of claims 13 to 16, wherein the first wheel link (8’) of the first pair of wheel links (8) comprises a fifth pivot coupling (27) connected to the actuator assembly (6,7).

18. The container handling vehicle (501) according to any of claims 13 to 17, wherein the actuator assembly comprises an actuator link (7) pivotably connected to the first wheel link (8’) of the first pair of wheel links (8) to drive rotation of the first wheel link (8’) and the second wheel link (8”) of the first pair of wheel links (8).

19. The container handling vehicle (501) according to any of claims 13 to 18, wherein the first pair of wheel links (8) and the second pair of wheel links (9) move in the same direction around their respective first pivot coupling (3) and third pivot coupling (29).

20. The container handling vehicle (501) according to any of claims 12 to 19, wherein the coupler link system (14-1,14-2,14-3) comprises: a rotatable plate (14-3) rotatably connectable to a rotational shaft (6’) of a wheel lift motor (6); a first coupler link (14-1) connectable between the first wheel link (9’) of the second pair of wheel links and the rotatable plate (14-3); a second coupler link (14-2) connectable between the first wheel link (8’) of the first pair of wheel links and the rotatable plate (14-3).

21. The container handling vehicle (501) according to claim 20, wherein the second pivot coupling (4) is configured to rotatably connect the first wheel link (8’) of the first pair of wheel links (8) to the second coupler link (14-2) and the fourth pivot coupling (30) is configured to rotatably connect the first wheel link (9’) of the second pair of wheel links (9) to the first coupler link (14-1).

22. The container handling vehicle (501) according to claim 20 or claim 21, wherein the first pair of wheel links (8) and the second pair of wheel links (9) move in opposite directions around their respective first pivot coupling (3) and third pivot coupling (29).

23. The container handling vehicle (501) according to any of claims 12 to 22 , comprising: a first drive shaft (22a) arranged in the first section (Si) and interconnecting the first and second wheel links (9 ’,9”) of the second pair of wheel links (9), wherein the first drive shaft (22a) is operatively connected to drive the first wheel (11a) and the second wheel (11b) of the first set of wheels (11); and a second drive shaft (22b) arranged in the third section (S3) and interconnecting the first and second wheel links (8’, 8”) of the first pair of wheel links (8), wherein the second drive shaft (22b) is operatively connected to drive the third wheel (11c) and the fourth wheel (nd) of the first set of wheels (11).

24. The container handling vehicle (501) according to any preceding claim, wherein the vehicle frame (10) comprises a first vertical subframe (40) forming part of the first section (Si) and a second vertical subframe (41) forming part of the third section (S3) and a horizontal upper member (42) forming part of the second section (S2), and wherein the horizontal upper member (42) is arranged above the cavity (26).

25. The container handling vehicle (501) according to claim 24, wherein the horizontal upper member (42) is connected to the first vertical subframe (40) and the second vertical subframe (41).

26. The container handling vehicle (501) according to claim 24 or claim 25, wherein the vehicle frame (10) comprises side cross-members (43) arranged on opposite sides of the cavity (26). l . An automated storage and retrieval system comprising a container handling vehicle (501) according to any preceding claim, wherein the automated storage and retrieval system comprises a frame structure (100) having a plurality of storage columns (105) for accommodating vertical stacks of storage containers (106), optionally wherein the frame structure (100) has a rail system (108) upon which the container handling vehicle (501) may move in two perpendicular directions above the storage columns (105).

28. A method of assembling a container handling vehicle for an automated storage and retrieval system , the method comprising the steps of: assembling a first section (Si) of the vehicle frame (10), the first section (Si) comprising:

- a first wheel (11a) and a second wheel (11b) of a first set of wheels (n),

- a first drive motor (20a),

- a first wheel link 8’ and a second wheel link (8”) of a first pair of wheel links (8),

- a first wheel (12a) and a fourth wheel (i2d) of a second set of wheels (12); assembling the third section (S3) of the vehicle frame (10), the third section comprising:

- a third wheel (11c) and a fourth wheel (nd) of the first set of wheels (n),

- a second drive motor (20b),

- a first wheel link (9’) and a second wheel link (9”) of a second pair of wheel links (9), a second wheel (12b) and a third wheel (12c) of the second set of wheels (12); connecting a second section (S2) of the vehicle frame (10) to the first section (Si) of the vehicle frame (10) and the third section (S3) of the vehicle frame (10); interconnecting the first wheel link (8’) of the first pair of wheel links (8) to the first wheel link (9’) of the second pair of wheel links (9) by a single coupler link system (14’;14-1, 14-2, 14-3).

29. The method of claim 28, wherein the container handling vehicle is the container handling vehicle of any of claims 1 to 27.