DE102022115056A1 - Hydraulically damping bearing - Google Patents

Abstract

The invention relates to a hydraulically damping bearing (10) with an outer sleeve (12) which encloses an interior, a bearing core (14), and at least one elastomer body (16) which is arranged between the outer sleeve (12) and the bearing core (14). , at least one separating membrane (18, 20), which divides the interior into at least two chambers (22, 24) filled with hydraulic fluid and has at least one channel connecting the at least two chambers filled with hydraulic fluid in a fluid-communicating manner, wherein the elastomer body (16) in addition to at least one separating membrane (18, 20) comprises at least one deflectable decoupling membrane (26) arranged between the chambers (22, 24) and made of the same material as the elastomer body, the outer circumferential connection (58) of the decoupling membrane (26) being in relation to the outer sleeve ( 12) is stationary. The invention therefore provides a further improved hydraulically damping bearing (10) that can be manufactured easily and is therefore cost-effective.

Description

The invention relates to a hydraulically damping bearing.

Moving parts on machines or vehicles usually generate vibrations that are transmitted to the entire machine or vehicle. Bearings are used to decouple the rest of the machine or vehicle from the moving parts. If vibration damping or cancellation is also required, special hydraulic bearings can be used. These hydraulic bearings include an outer sleeve, a support body which has a core, an outer support structure and an elastomer body connecting the support structure and the core, the support body and the outer sleeve delimiting at least two chambers filled with a fluid. The chambers can be connected to one another via a channel to which a valve can be assigned.

Hydraulically damping bearings are used in particular in the chassis area to dampen or cancel vibrations that are introduced into the chassis in particular by road excitations. These induced vibrations cause a relative movement of the core and outer sleeve. The volume of one chamber is increased and at the same time the volume of the other chamber is reduced. The fluid thereby experiences a differential pressure which pushes the fluid across the channel from the chamber with the reduced volume to the chamber with the increased volume. If the channel has a small diameter, the frictional effects of the fluid cause the system to be damped. However, if the channel has a large diameter, mass inertia effects of the fluid in the channel lead to absorber effects.

With high-frequency vibrations of small amplitudes, which make up the acoustically relevant range, there is an increase in the dynamic stiffness of conventional hydraulic bearings. When flowing through the damping channel, the liquid can no longer follow the exciting vibrations due to inertial effects. Volume changes caused by high-frequency vibrations cause the membranes of the elastomer body to stretch, so that the internal pressure in the chambers increases. The resulting stiffness, as the sum of the static stiffness and the membrane stiffness, is significantly increased compared to the initial stiffness. At small amplitudes, the effect of dynamic hardening of rubber compounds, the so-called Payne effect, continues to work. This results in a high dynamic stiffness of the bearing, which leads to poor acoustic properties. This is equivalent to a low level of insulation provided by the bearing, so that high-frequency vibrations of small amplitude in particular are acoustically perceptible.

Out of DE 10 2013 105 326 A1 a hydraulically damping bearing is known in which the elastomeric body has an additional decoupling membrane which is arranged between the channel and a cavity introduced in the elastomeric body. This arrangement of the decoupling membrane ensures that it lies outside the load path and is not stressed by static deflections. This ensures effective decoupling in all operating states. In particular, the decoupling membrane is not stressed by static deflections of the socket. The disadvantage, however, is that the path of the decoupling membrane cannot be restricted or can only be restricted with difficulty by means of limiting means. This means that the membrane experiences larger deflections, which on the one hand limits its service life and, on the other hand, can significantly reduce the overall damping of the bearing.

The object of the invention is to provide a further improved hydraulically damping bearing with a decoupling membrane. The decoupling membrane should be characterized by a long service life and its deflection should be adjustable. Furthermore, the bearing should be easy to manufacture and therefore cost-effective.

Main features of the invention are specified in claim 1. Refinements are the subject of claims 2 to 10.

In a hydraulically damping bearing with an outer sleeve that encloses an interior, a bearing core, at least one elastomer body that is arranged between the outer sleeve and the bearing core, at least one separating membrane that divides the interior into at least two chambers filled with hydraulic fluid and at least one has at least two fluid-communicating connecting channel filled with hydraulic fluid, it is provided according to the invention that, in addition to the at least one separating membrane, the elastomer body comprises at least one deflectable decoupling membrane arranged between the chambers and made of the same material as the elastomer body, wherein the outer circumferential connection of the decoupling membrane in relation to the Outer sleeve is stationary.

The invention provides a hydraulically damping bearing in which the decoupling membrane as well as the separating membrane is arranged between the chambers filled with hydraulic fluid. The decoupling membrane can also be between the chambers are deflected so that when the volume of one chamber increases, the decoupling membrane can be deflected by the negative pressure into the chamber with the increasing volume. In relation to the outer sleeve, the outer peripheral connection of the decoupling membrane is stationary, so that static deflections of the bearing core or the outer sleeve do not put a strain on the decoupling membrane. However, the stationary attachment of the decoupling membrane does not prevent a dynamic deflection of the decoupling membrane in relation to the outer sleeve. Furthermore, the decoupling membrane is designed in such a way that it reacts sensitively to small vibration amplitudes. The decoupling membrane can have an expansion stiffness that is less than or equal to the individual expansion stiffnesses of the chambers. This means it can compensate for the smallest volume changes due to small vibration amplitudes. An outflow or an inflow of hydraulic fluid, e.g. B. through a channel between the chambers into or out of the adjacent chambers does not necessarily take place if the decoupling membrane is deflected. The bearing can, for example, have a channel that connects the chambers to one another in fluid communication. In the case of large vibration amplitudes, hydraulic fluid can be pumped between the chambers through the channel in order to compensate for the changed volumes. If the decoupling membrane were to be damaged, a direct connection is simply created between the chambers so that the hydraulic fluid remains in the chambers. This prevents fluid loss from the bearing if the decoupling membrane is damaged. Furthermore, in the event of minor damage to the decoupling membrane, a residual hydraulic function of the hydraulic damping bearing can be retained. Due to the arrangement between the chambers, the decoupling membrane and thus the elastomer body can be produced easily and therefore cost-effectively.

The bearing can have a single or multiple decoupling membranes. However, a decoupling membrane may be sufficient to provide decoupling from high vibration frequencies.

According to one example, the at least one decoupling membrane can be arranged between at least two struts mounted in a stationary manner relative to the outer sleeve and can preferably be connected to the at least two struts in a materially bonded manner. The struts are part of the outer peripheral connection of the decoupling membrane. In addition, the struts are stationary in relation to the outer sleeve.

In this example, the decoupling membrane is limited and held by the struts. The struts further preferably extend parallel to a central longitudinal axis of the core or the bearing, with the outer sleeve extending around the central longitudinal axis, and can further preferably be part of a rectangular frame for the decoupling membrane. The decoupling membrane can then have at least two straight edge sections. In this way, the installation space in the interior can be optimally utilized.

According to a further example, the bearing in the interior can further have at least one support body to which the at least two struts are fixed in place, the at least two struts preferably extending between two support rings which support the elastomer body in a circumferential direction around the bearing core.

The support body is then mounted in a stationary manner relative to the outer sleeve. Advantageously, the support body can have two support rings which are axially spaced apart from one another, extend around the bearing core and support the elastomer body in the circumferential direction. In this example, the struts can extend between the support rings, preferably in a straight line. The decoupling membrane can thus be fastened in a stationary manner to the outer sleeve between the chambers using simple means.

It is also conceivable, for example, that the bearing in the interior has at least one half-shell mounted in a stationary manner relative to the outer sleeve.

The half-shell can z. B. be a channel half-shell, which in this case has at least parts of the channel that connects the chambers in a fluid-communicating manner. If the volumes of the chambers change, in addition to the volume compensation through the decoupling membrane, hydraulic fluid can be exchanged through the channel between the chambers.

Alternatively or additionally, the half-shell can lie in the radial load path of the bearing and serve to adjust the radial free path or the identification profile of the bearing. Such a half-shell can also be referred to as a free-path limiting half-shell.

According to a further example, at least one of the chambers can have at least one stop element for the decoupling membrane to limit a deflection of the decoupling membrane.

By limiting the deflection of the decoupling membrane, overloading of the decoupling membrane is avoided at large vibration amplitudes.

The stop element can, for example, be part of a half-shell or a separate insert element. The stop element can, for example, have sieve, grid, hole structures, ribs and/or knobs.

Hydraulic fluid can thus escape when the decoupling membrane is deflected on the side facing the stop element without any noise, for example smacking noises, occurring. This also minimizes the response time of the deflection of the decoupling membrane to vibrations.

The stop element can z. B. be a projection of the channel half-shell, which protrudes through the interior into an area in which the decoupling membrane is arranged.

Furthermore, the stop element can be a uniform component of the elastomer body, for example a projection from and/or on the separating membrane. In this case, the stop element preferably has ribs and/or knob structures on the side facing the decoupling membrane.

For example, the outer sleeve itself can form a stop element.

If the stop element is part of a channel half-shell, a free-travel limiting half-shell, part of the elastomer body and/or the outer sleeve, then it is an integral part of a component that is required anyway. This means that it can be manufactured easily and, in the preferred case, a manufacturing step can be saved.

It is further preferred that the decoupling membrane can be arranged between two stop elements. A stop element can then be arranged on the outer sleeve or be formed by a part of the outer sleeve and the other stop element can be provided by the channel half-shell or an insert element.

Furthermore, it is grateful that the decoupling membrane can, for example, have at least one projection directed towards the stop element, preferably a rib and/or a knob, which can further preferably be made of the same material as the decoupling membrane.

This projection directed towards the stop element allows the limit amplitude of the decoupling to be defined, above which the decoupling membrane rests on the stop element, since the length of the free path between the decoupling membrane and the stop element can thus be changed. To reduce the limit amplitude, e.g. B. an increase in the projection on the decoupling membrane can be provided. The limit amplitude is defined in such a way that, with a closed channel, a static deflection of the bearing leads to the decoupling membrane being completely in contact with the stop element. Beyond the limit amplitude, the displaced fluid volume cannot be further compensated for by the bulging of the decoupling membrane.

It is further conceivable that the limit amplitude of the bearing is in a range between 0.005 mm and 0.5 mm, preferably between 0.01 mm and 0.3 mm, more preferably between 0.03 mm and 0.1 mm.

• 1 eine schematische Querschnittsdarstellung des Lagers;
• 2 eine schematische Darstellung des Elastomerkörpers;
• 3 eine schematische Darstellung eines Stützkörpers; und
• 4a-c eine schematische Darstellung des Elastomerkörper und der Halbschale in verschiedenen Ansichten.

Further features, details and advantages of the invention emerge from the wording of the claims and from the following description of exemplary embodiments based on the drawings. Show it:

• 1 a schematic cross-sectional representation of the bearing;
• 2 a schematic representation of the elastomer body;
• 3 a schematic representation of a support body; and
• 4a-c a schematic representation of the elastomer body and the half-shell in different views.

This in 1 The hydraulic damping bearing shown is referred to in its entirety below with the reference number 10.

The bearing 10 has an outer sleeve 12 which encloses an interior space. The outer sleeve 12 can extend along a central longitudinal axis 52 of the bearing 10.

Furthermore, the bearing 10 has a bearing core 14, which is at least partially arranged in the interior. The bearing core 14 is thus at least partially enclosed by the outer sleeve 12.

Between the outer sleeve 12 and the bearing core 14, the bearing 10 has at least one elastomer body 16, which is arranged in the interior and can be cohesively connected to the bearing core 14.

The elastomer body 16 has at least one separating membrane 18, 20, which divides the interior into at least two chambers 22, 24. The chambers 22, 24 are filled with hydraulic fluid, for example an oil. In this example, the separating membranes 18, 20 extend from the bearing core 14 in two opposite directions to the outer sleeve 12. When the bearing core 14 is deflected in relation to the outer sleeve 12, the separating membranes 18, 20 are also moved in relation to the outer sleeve 12.

Furthermore, the elastomer body 16 has a decoupling membrane 26 which, in addition to the separating membrane 18, 20, divides the interior into the chambers 22, 24. The decoupling membrane 26 is therefore arranged between the chambers 22, 24 and can be deflected into each of the chambers 22, 24, whereby the decoupling membrane 26 can be softer to expand than the separating membranes 18, 20. The decoupling membrane 26 can have an expansion stiffness that is less than or equal to the individual expansion stiffnesses of the chambers 22, 24. The decoupling membrane 26 thus forms part of a partition between the chambers 22, 24. The decoupling membrane is fixed to the connection 58 on the struts 28, 30. The chambers 22, 24 also have areas with narrow volumes, such as. Am 1 above or below the decoupling membrane 26. Furthermore, the decoupling membrane 26 is formed in one piece with the elastomer body 16.

If the bearing core 14 z. B. is deflected into the chamber 22, the volume of the chamber 22 is reduced. The pressure of the hydraulic fluid in the chamber 22 is thus increased. At the same time, the bearing core 14 is deflected out of the chamber 24 so that its volume is increased. The pressure of the hydraulic fluid in the chamber 24 is thus reduced. A pressure difference therefore arises between the chambers 22, 24, which also acts on the decoupling membrane 26. Therefore, the decoupling membrane 26 is deflected from the chamber 22 into the chamber 24 and thus increases the volume of the chamber 22 and reduces the volume of the chamber 24.

The decoupling membrane 26 can thus at least partially compensate for the pressure difference between the two chambers 22, 24. The outer membrane 60, 62 therefore has to inflate less. Since the inflation of the outer membrane 60,62 preferably requires a higher force with the same core deflection than the inflation of the decoupling membrane, the overall inflation stiffness of the bearing is lower due to the effect of the decoupling membrane. Since the liquid column between the chambers, which lies on both sides of the decoupling membrane, together with the decoupling membrane also represents a system capable of oscillation, this system also has a natural frequency. Due to the relatively large cross-section of this liquid-membrane column and its relative shortness, the natural frequency and thus a particularly high absorption of vibrations can be well tuned to particularly critical vibration ranges between 50 and 200 Hz.

Furthermore, the decoupling membrane 26 is also fixed in place in relation to the outer sleeve 12. Apart from a deflection of the decoupling membrane 26, the positional relationship between the outer connection 58 of the decoupling membrane 26 and the outer sleeve 12 is constant.

The bearing 10 can further have at least one stop element 42, 44 for limiting the deflection of the decoupling membrane 26. In this example, the outer sleeve 12 has the stop element 42, which limits the deflection of the decoupling membrane 26 into the chamber 22.

A further stop element 44 can be arranged on a half-shell 40 of the bearing 10 and limit the deflection of the decoupling membrane 26 into the chamber 24 in such a way that the limit amplitudes of the bearing movement in both directions are in the range between 0.005 mm to 0.5 mm, preferably between 0. 01 mm and 0.3 mm, more preferably between 0.03 mm and 0.1 mm.

In addition, at least one pressure relief valve 56 can be provided between the chambers 22, 24. The half-shell 40 may provide part of the channel between the chamber 22 and the chamber 24. A separate pressure relief valve 56 can be provided for each flow direction between the chambers 22, 24. Furthermore, a pressure relief valve can also work on both sides or can be omitted entirely.

In 2 the bearing 10 is shown without the outer sleeve 12 and half-shell 40. Visible are the elastomer body 16 and the bearing core 14, with which the elastomer body 16 can be cohesively connected, e.g. B. by vulcanization. The decoupling membrane 26 is, as already, off 1 can be seen, arranged in the radial direction with respect to the longitudinal axis 52 closer to the outer sleeve 12 than to the bearing core 14.

A support body 34, which is in 3 is shown in more detail, can support the elastomer body 16. The support body 34 forms a cage that clamps the elastomer body 16 in the interior. For this purpose, the support body 34 has support rings 36, 38 which extend around the longitudinal axis 52. In this example, the support rings 36, 38 are arranged at the ends of the elastomer body 16 in the axial direction with respect to the longitudinal axis 52.

At least one strut 28, 30, 32 can extend between the support rings 36, 38. In the In this example, three struts 28, 30, 32 are shown. In this example, the struts 28, 30, 32 extend parallel to the longitudinal axis 52 in a straight line.

The struts 28, 30, 32 and the support rings 36, 38 are arranged near the outer sleeve 12 and are fixed in place in the bearing 10 in relation to the outer sleeve 12.

The struts 28 and 30 delimit a window 54 in the support body 34. As in 4a shown, the decoupling membrane 26 can extend in the window 54 between the struts 28 and 30. The decoupling membrane 26 is therefore fixed in place in relation to the outer sleeve 12 via the struts 28 and 30, the decoupling membrane 26 being able to be deflected through the window 54 into the chambers 22, 24.

In 4a is compared to 3 the half-shell 40 is also shown. The half-shell 40 can be designed as a channel half-shell, which connects the chambers 22, 24 in fluid communication via a channel 48. Furthermore, the half-shell 40 is designed as a free-travel limiting half-shell since it lies in the radial load path of the bearing.

Channel 48 is in the 4b and 4c shown in more detail and extends in the circumferential direction around the longitudinal axis 52 at an axial end region of the bearing 10. 4c shows a bearing 10 rotated through 180° about the longitudinal axis 52. An area of the outside 50 of the elastomer body 16, which encloses the strut 32, is visible. It can be seen that the channel 48 is formed in the elastomer in the area between the strut 32 and the outer sleeve 12. Furthermore, this channel 48 is extended on both sides by two channel half-shells 40. It is also conceivable that at least one valve can be arranged between the strut 32 and the outer sleeve 12.

The invention is not limited to one of the previously described embodiments, but can be modified in many ways.

All features and advantages arising from the claims, the description and the drawing, including constructive details, spatial arrangements and process steps, can be essential to the invention both individually and in a wide variety of combinations.

Reference symbol list

10

camp

12

Outer sleeve

14

Bearing core

16

Elastomer body

18

Separation membrane

20

Separation membrane

22

chamber

24

chamber

26

decoupling membrane

28

strut

30

strut

32

strut

34

Support body

36

Support rings

38

Support rings

40

half shell

42

stop element

44

stop element

46

head Start

48

channel

50

Outside

52

Longitudinal axis

54

Window

56

Pressure relief valve

58

Connection

60

Outer membrane

62

Outer membrane

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102013105326 A1 [0005]

Claims (10)

Hydraulically damping bearing with an outer sleeve (12) which encloses an interior, a bearing core (14), at least one elastomer body (16) which is arranged between the outer sleeve (12) and the bearing core (14), at least one separating membrane (18, 20), which divides the interior into at least two chambers (22, 24) filled with hydraulic fluid and has at least one channel connecting the at least two chambers (22, 24) filled with hydraulic fluid in a fluid communication manner, characterized in that the elastomer body (16) additionally to the at least one separating membrane (18, 20) comprises at least one deflectable decoupling membrane (26) arranged between the chambers (22, 24) and made of the same material as the elastomer body, wherein an outer circumferential connection (58) of the decoupling membrane (26) in relation to the outer sleeve (12) is stationary. Hydraulically dampened bearing Claim 1 , characterized in that the at least one decoupling membrane (26) is arranged between at least two struts (28, 30) mounted in a stationary manner relative to the outer sleeve (12). Hydraulically dampened bearing Claim 2 , characterized in that the bearing (10) further has at least one support body (34) in the interior, comprising the at least two struts (28, 30), the at least two struts (28, 30) preferably being located between two support rings (36, 38) which support the elastomeric body (16) in a circumferential direction around the bearing core (14). Hydraulically dampened bearing Claim 1 , characterized in that the bearing (10) has at least one half-shell (40) mounted in a stationary manner relative to the outer sleeve (12) in the interior. Hydraulic damping bearing according to one of the Claims 1 until 4 , characterized in that at least one of the chambers (22, 24) has at least one stop element (42, 44) for the decoupling membrane (26) to limit a deflection of the decoupling membrane (26). Hydraulically dampened bearing Claim 5 , characterized in that the stop element (42, 44) has a sieve, grid and/or a hole structure and alternatively or additionally ribs and/or knobs. Hydraulically dampened bearing Claim 5 or 6 , characterized in that the stop element (42) is arranged on the outer sleeve (12) and is preferably formed by a part of the outer sleeve (12). Hydraulic damping bearing according to one of the Claims 5 until 7 , characterized in that the stop element (42) is arranged on the elastomer body (16) and is preferably formed by a part of the elastomer body (16). Hydraulically dampened bearing Claim 4 and one of the Claims 5 until 8th , characterized in that the stop element (44) is arranged on the half-shell (40). Hydraulic damping bearing according to one of the Claims 5 until 9 , characterized in that the decoupling membrane (26) has at least one projection (46) directed towards the stop element (42, 44), preferably a rib or a knob, which is preferably made of the same material as the decoupling membrane (26).

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