GB2171299A

GB2171299A - A castor wheel provided with a directional locking device

Info

Publication number: GB2171299A
Application number: GB08603297A
Authority: GB
Inventors: Fritz Vollberg
Original assignee: Schulte Soehne Co A GmbH
Current assignee: Schulte Soehne Co A GmbH
Priority date: 1985-02-16
Filing date: 1986-02-11
Publication date: 1986-08-28
Also published as: GB2171299B; FR2577477B1; GB8603297D0; FR2577477A1; DE3505504A1

Abstract

A castor wheel is provided with a directional locking device 16 provided in a housing 20 which is arranged on the rotary mounting head 14 that rotatably holds the wheel fork 10. A locking slider 17 which is biassed to a release position by a spring member 35 is guided in the housing 20 to be horizontally displaceable between a release position and a locking position in which a tongue 18 engages into an opening 15 provided in the back 13 of the wheel fork 10. The actuating lever 24 is pivotable about an axis which extends in the direction of displacement of the locking slider 17, and has a control arm 28 which bears against an inclined support track on the locking slider 17 through a roller 30. <IMAGE>

Description

SPECIFICATION A castor wheel provided with a directional locking device This invention relates to a castor wheel provided with a directional locking device comprising a housing connected to a rotary mounting head rotatably holding the wheel fork of the wheel and in which a locking slider is mounted which is subjected to the force of a spring member and is horizontally displaceable by way of an actuating lever pivotably mounted on the housing, between a release position and a locking position in which it engages an opening in the top of the wheel fork.

In a directional locking device for castor wheels, which is disclosed in German laid-open application (DE-OS) No 32 12 994, provided in the back of the wheel fork are two mutually diametrally oppositely disposed openings which fix the position for running straight ahead, wherein the locking slider can engage by means of a locking tongue into one of those openings, for fixing the castor wheel in the position for running straight ahead. The locking slider is horizontally displaceably disposed in a housing which can be connected by flange means to the rotary mounting head of the castor wheel, and is moved by a pivotably actuating lever, the plane of pivotal movement of which coincides with the direction of displacement of the locking slider.

That necessarily means that the actuating lever projects substantially beyond the housing which carries the locking slider, and that has a disadvantageous effect in particular in relation to castor wheels which are fixed to stackable refuse containers.

The problem of the present invention is to provide a directional locking device for castor wheels, by means of which the structural length of the castor wheel itself can be substantially reduced.

According to the present invention there is provided a castor wheel provided with a directional locking device comprising a housing connected to a rotary mounting head rotatably holding the wheel fork of the wheel and in which a locking sli der is mounted which is subjected to the force of a spring member and is horizontally moved against the spring force by way of an actuating lever pivot ably mounted on the housing, between a release position and a locking position in which it engages an opening in the top of the wheel fork, the actuat ing lever being pivotal about an axis which ex tends in the direction of displacement of the locking slider and having a control arm which acts against an inclined track provided on the locking slider.

By virtue of invention, the structural length of a castor wheel which is fitted wth a directional lock ing device is substantially reduced, in particular in the region of the back of the wheel fork, so that such castor wheels are better suited to being se cured to containers which must be stackable in themselves together with the rollers which are mounted thereto by flange means.

In order on the one hand to be able to ensure easy operation of the directional locking device and on the other hand to ensure that the locking slider is securely held in its locking position, mounted on the control arm of the actuating lever is a rolling member which is supported on the one hand against a guide wall of the housing and on the other hand against the support track of the locking slider. The rolling member is advantageously formed by a tubular member which is disposed in an aperture in the control arm and which is supported by a rolling member holder.

Instead of a rolling member holder which engages over the rolling member on the outside thereof in a region thereof, the holder may also be in the form of a bent-over portion which engages into the tubular portion and which forms an axis member for the rolling member.

Instead of a tubular portion serving as the rolling member, the rolling member may also advantageously be in the form of a ball which is mounted in the control arm of the actuating lever.

So that the locking slider can normally remain in its locking position and can only be removed from the locking position by suitable movement of the actuating lever, the inclined track, in accordance with a further feature of the invention, is provided at its location that corresponds to the locking position of the locking slider, with a retaining depression which is substantially the same as the size of the rolling member. When a ball is sued as the rolling member, the retaining depression may also be formed by a bore of smaller diameter than the diameter of the ball. Finally, particularly when a tubular portion is used as the rolling member, it may be advantageous for the support track to be formed from a bent-over limb portion of the locking slider.

In order to keep the number of components forming the directional locking device low, the spring member is formed from a loop spring which is supported on the housing and which both holds the locking slider in a position of bearing against the guide track of the housing and also loads it in the release direction. The loop spring and the spindle for mounting the actuating lever in the housing fix all components in the housing so that there is no need for further fixing means.

For the sake of ease of operation of the actuating lever, the actuating lever is advantageously in the form of a tipping lever and has an actuating arm consisting of a locking arm and a release arm.

The directional locking device may be integrated into the rotary mounting head in various ways.

Thus on the one hand the housing may be an integral component of the rotary mounting head of the castor wheel while on the other hand the housing may also be in the form of an independent compo nent which can be connected to the rotary mounting head or the castor wheel so that castor wheels which in themselves do not have any directional locking device can be subsequently fitted with such a directional locking device.

Some embodiments of the invention will now be described, by way of examples, with reference to the accompanying drawings, in which: Figure 1 is a view in longitudinal section of the rotary mounting head of a castor wheel, with a directional locking device which is integrated in one piece and which is in the locking position, the limbs of the fork being broken away and the wheel disposed between the limbs of the fork having been omitted; Figure 2 is an end view of the rotary mounting head and directional locking device shown in Figure 1; Figure 3 is a plan view of the rotary mounting head and directional locking device shown in Figures 1 and 2; Figure 4 is a view in section taken along the line IV-IV indicated in Figure 1 of the directional locking device arranged in the interior of its housing on the rotary mounting head;; Figure 5 is a plan view in section taken along the line V-V indicated in Figure 1 of the directional locking device disposed on the rotary mounting head; Figure 5 is a view in longitudinal section of a further embodiment of a directional locking device, the housing of which is connected to the rotary mounting head of a castor, for example by welding; Figure 7 is a plan view of the directional locking device shown in Figure 6, with the rotary mounting head of the castor wheel; Figure 8 is a view in longitudinal section of a further embodiment of a directional locking device which can be connected for example by screwing to the rotary mounting head of a castor wheel; Figure 9 is a plan view of the embodiment shown in Figure 8;; Figure 10 is a further embodiment of a directional locking device which can be connected to the rotary mounting head and in which the rolling member which is in the form of a tubular portion is held in position by an axis member; and Figure ii is a view in section taken along the line Xl-XI indicated in Figure 10.

A castor wheel fork 10 which accommodates a runner wheel (not shown) is pivotably mounted by means of its upper end 13 which connects the two limbs 11 and 12 of the fork 10, in a rotary mounting head 14, with the interposition of for example rings of balls. At two diametrically oppositely disposed peripheral portions of the upper end 13 of the fork structure 10, on the longitudinal centre line between the limbs 11 and 12, the upper end 13 of the fork 10 has openings 15. A locking tongue 18 of a locking slider 17 of a directional locking device 16 can engage into one of the openings 15, to lock the castor wheel in the direction in which it is to move.

In the embodiment shown in Figures 1 to 5, a fixing plate 19 of the rotary mounting head 14 is extended in its longitudinal direction to form a housing 20 for accommodating the components of the directional locking device 16. The housing 20 comprises two lateral angle guide portions 21 and 21' and a guide wall 22 which is arranged transversely with respect thereto and which closes off the housing 20 at the rear. Both the guide wall 22 and the fixing plate 19 are provided with a mounting boss or flange 23 which extends above the top of the fixing plate 19 with an actuating lever 24 being mounted between the mounting boss or flanges 23 on a spindle 25 which passes through the mounting boss and flange 23.The actuating lever 24 which is in the form of a tipping lever has an actuating arm which is arranged above the top side of the fixing plate 19 and which extends transversely with respect to the longitudinal direction of the fixing plate 19 and which comprises a locking arm portion 26 and a release arm portion 27. A control arm 28 of the actuating lever 24 into the housing 20 of the directional locking device and is located at a small spacing from and is in parallel relationship with the guide wall 22 of the housing 20. The control arm 28 of the actuating lever 24 is operatively connected to the above-mentioned locking slider 17 which is guided displaceably on the inwardly bent limbs of the angle guide portions 21 and 21' transversely with respect to the plane of pivotal movement of the actuating lever 24, that is to say in the longitudinal direction of the fixing plate 19.At its side towards the control arm 28, the locking slider 17 has an inclined support track 29 on which a rolling member 30 can run. The rolling member 30 is mounted on the control arm 28 and bears against the guide wall 22. In the illustrated embodiments, the rolling member 30 comprises a tubular portion and is mounted in an aperture 31 in the control arm 28. The rolling member 30 is secured in its position in the aperture 31 in the control arm 28 by a rolling member holder 32 which is connected to the control arm 28.In the embodiment shown in Figures 1 to 5, the rolling member holder 32 comprises a bent-over portion which is pressed out by virtue of the formation of the aperture 31 and which engages over the inward side of the tubular portion disposed in the aperture 31, in such a way that, upon pivotal movement of the actuating lever 24, only the tubular portion 30 remains in contact with the support track 29 of the locking slider 17. As can be seen in particular from Figure 5, the locking slider 17 is illustrated in its locking position with its locking tongue 18 engaging into the opening 15 in the upper end 13 of the fork 10. With the locking slider 17 in that position in which it is pushed forward towards the central pivot point, a retaining depression 33 for receiving the rolling member 30 is disposed at one end of the support track 29. For the purposes of holding the locking slider 17 down on the bent-over portions provided at the lower sides of the angle guide portions 21 and 21' on the one hand and for loading the locking slider 17 in the release direction on the other hand, there is provided a loop spring 35 which is held to the housing by support means 34 provided on the fixing plate 19 and which engages into holes provided in the locking slider 17. Guide fingers 36 are arranged on both sides of the locking tongue 18 of the locking slider 17, the guide fingers 36 ensuring a locking readiness position when the directional locking device is actuated without the fork 10 being in such a position that the locking tongue 18 can engage directly into an opening 15.

The embodiment shown in Figures 1 to 5 illustrates the locking position of the directional locking device, with the locking tongue 18 being engaged into one of the two oppositely disposed openings 15 in the back 13 of the wheel fork. If now the arrangement is to be put into a release position for pivotal movement of the wheel fork relative to the fixing plate 19, the actuating lever 24 is pivoted in the anti-clockwise direction, as viewed in Figures 2 and 4, by pressing the release arm 27 downwardly.

During that pivotal movement of the actuating lever 24, the spring 35 holds the support track 29 of the locking slider 17 in contact with the rolling member 30 so that the locking slider 17 is moved towards the guide wall 22 whereby the locking tongue 18 moves out of the opening 15 in the back 13 of the fork 10 and releases same for pivotal movement. To put the arrangement into the locking position, the locking arm 26 of the actuating lever 24 is pressed downwardly into the position shown in the drawings, whereby, by means of the rolling member 30 and the support track 29, the locking slider 17 is advanced towards the central pivot point of the rotary mounting head 14 against the action of the spring 35, into the position shown in the drawings.If at that time one of the openings 15 is not at the required position, then the locking tongue 18 moves over the edge of the circular upper end 13 of the fork structure 10 and is urged downwardly by the spring 35. Now, when the trolley or truck which is fitted with the castor wheels moves, as soon as the wheel fork pivots into such a position that one of the openings 15 takes up a position beneath the locking tongue 18, the locking tongue 18 engages into the opening 15 and thus locks the wheel fork 10 relative to the fixing plate 19, as can be seen from the drawings.

The two embodiments shown in Figures 6 to 9 differ in regard to structure from the above-described embodiment shown in Figures 1 to 5, only in that the housing 20' which accommodates the components of the directional locking device is a component which is separate from the fixing plate 19' and from a cover plate member 37 of the rotary mounting head 14. In the embodiment shown in Figures 6 and 7, the rotary mounting head 14 can be connected to a truck or trolley or the like by way of a trunnion member 39 which is mounted on the cover plate member 37 and the mounting plate member 38. The housing 20' of the directional locking device is fitted on to the edge of the cover plate member 37 and may be connected thereto for example by welding.

In the embodiment shown in Figures 8 and 9, the housing 20' engages under the fixing plate 19' and, similarly to the fixing plate 19', has two fixing bores 40 by way of which the housing 20' of the directional locking device, together with the fixing plate 19, may be fixed to a truck, trolley or the like.

The remainder of the structure and the mode of operation of the directional locking devices shown in Figures 6 and 7 and in Figures 8 and 9 respectively are the same as in the case of the directional locking device shown in Figures 1 to 5.

The embodiment of a directional locking device shown in Figures 10 and 11 substantially corresponds to that shown in Figures 8 and 9. Unlike the latter however, in this embodiment the rolling member 30 is held in the aperture 31 in the control arm by a bent-over portion 41 which engages into the rolling member 30 and which forms a bearing member for the rolling member 30. As a further difference in relation to the above-described embodiments, the support track 29 of the locking slider 17 in the embodiment shown in Figures 10 and 11 is formed by a bent-over limb 42 on the locking slider 17. By virtue of that arrangement the support track 29 has a wider contact surface for the rolling member 30.

In some embodiments the rolling member may be in the form of a bail.

Claims

1. A castor wheel provided with a directional locking device comprising a housing connected to a rotary mounting head rotatably holding the wheel fork of the wheel and in which a locking slider is mounted which is subjected to the force of a spring member and is horizontally moved against the spring force by way of an actuating lever pivotably mounted on the housing, between a release position and a locking position in which it engages an opening in the top of the wheel fork, the actuating lever being pivotal about an axis which extends in the direction of displacement of the locking slider and having a control arm which acts against an inclined track provided on the locking slider.

2. A castor wheel provided with a directional locking device as claimed in claim 1, in which a rolling member is mounted on the control arm of the actuating lever which bears on the one hand against a rear wall of the housing and on the other hand against the support track of the locking slider.

3. A castor wheel provided with a directional locking device as claimed in claim 2, in which the rolling member is formed by a tubular member which is arranged in an aperture in the control arm and which is supported by a holder.

4. A castor wheel provided with a directional locking device as claimed in claim 3, in which the holder is in the form of a bent-over portion which engages into the tubular member and which forms a bearing member for the rolling member.

5. A castor wheel provided with a directional locking device as claimed in claim 2, in which the rolling member comprises a ball which is mounted in the control arm of the actuating lever.

6. A castor wheel provided with a directional locking device as claimed in any one of the preceding claims, in which, at the location on the inclined track that corresponds to the locking position of the locking slider, the track is provided with a retaining depression in which the rolling member can seat.

7. A castor wheel provided with a directional locking device as claimed in any one of the preceding claims, in which the inclined track is formed from a bent-over limb portion of the locking slider.

8. A castor wheel provided with a directional locking device as claimed in any one of the preceding claims, in which the spring member is formed from a loop spring which is supported on the housing -and which holds the locking slider in contact against the guide track of the housing and also loads it in the release direction.

9. A castor wheel provided with a directional locking device as claimed in any one of the preceding claims, in which the actuating lever is in the form of a tipping lever and has an actuating arm comprising a locking arm portion and a release arm portion.

10. A castor wheel provided with a directional locking device as claimed in any one of the preceding claims, in which the housing is an integral component of the rotary mounting head of the castor wheel.

11. A castor wheel provided with a directional locking device as claimed in any one of claims 1 to 9, in which the housing is in the form of an independent component which can be connected to the rotary mounting head of the castor wheel.

12. A castor wheel provided with a directional locking device substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 5, or Figures 6 and 7, or Figures 8 and 9, or Figures 10 and 11 of the accompanying drawings.