Hydraulic bushing with bearing point and method for producing such a bushing

Abstract

The present invention relates to a hydraulic bushing having support portions and a method for manufacturing such a bushing. The hydraulic bushing includes an outer bushing (4), a support core (6), an elastomer (8) disposed between the outer bushing (4) and the support core (6) and defining at least two fluid-filled chambers (10, 12), and a cage (14) vulcanized within the elastomer (8) and having at least one annular end piece (16) having an outer peripheral side (20), wherein the outer peripheral side (20) of at least one end piece (16) includes two support portions extending circumferentially, and a retraction portion (26) is formed between the support portions relative to an imaginary straight line (G) connecting the two support portions as a tangent, wherein the two support portions are subjected to a radially inward preload by the outer bushing (4).

Description

Technical Field

[0001] This invention relates to hydraulic bushings and methods for manufacturing such bushings. Background Technology

[0002] Hydraulic damping bushings, also known as hydraulic bushings or hydraulic supports, are used as chassis supports in motor vehicles, such as subframe supports or steering wheel supports, to dampen and / or attenuate vibrations. Radial damping hydraulic supports comprise at least two spaced fluid chambers separated from each other by diaphragms and / or elastomers and fluidly connected by a damping channel. During radial relative or opposite movements of the core relative to the outer tube, one of the two fluid chambers is at least locally compressed, or the other fluid chamber is at least locally expanded. Consequently, fluid within these chambers flows from one fluid chamber to the other via the damping channel. This achieves a damping effect and / or shock absorption.

[0003] Hydraulic bushings may include cages The cage may be made of plastic for cost and weight reasons. Here, the cage may include two end-side annular sections or end pieces connected by at least one web. The end-side region of this end piece may be referred to as a wing.

[0004] The cage's wings are typically compressed radially outward due to mechanical loads. These mechanical loads may arise, for example, from bushing forces or from internal fluid pressure. The following situation is particularly critical: the bushing operates at high temperatures. In this case, the temperature causes fluid expansion, resulting in bulging of the diaphragm that can be secured to the wings. If there are additional or alternative dynamic loads, the internal pressure continues to rise. Simultaneously, the high dynamic load on the bushing can also cause a portion of the force in the internal stop system to compress the wings radially outward. If the cage is made of plastic, its rigidity and strength decrease with increasing temperature.

[0005] The force is borne by the outer bushing, which is manufactured to rest against the cage at the ends. This creates a form fit. The more precisely the form fit is achieved, the less support force acts on the cage wings.

[0006] All of the aforementioned effects may cause the cage to deviate from the shape fit of the outer bushing. The plastic cage may flex and potentially bend as it comes into contact with the outer bushing. In particular, the web may also bend. Bending may result in incomplete contact with the outer bushing. This, in turn, can cause external or internal leakage, or cage breakage. It is leakage that causes the loss of the function of the hydraulically damping bushing.

[0007] A hydraulic support with a plastic cage and a plastic outer bushing is known from EP2522878B1. Reliable fixation of the cage is achieved by using two suitable plastic materials that can be interconnected by laser transmission welding for the cage and the outer bushing. Stable positioning should be ensured against axial forces. The material pairing of the cage and the outer bushing should be weldable. However, the joining of the plastic cage to the metal outer bushing cannot be achieved by welding. Summary of the Invention

[0008] Therefore, the objective of this invention is to provide a hydraulic bushing and a corresponding manufacturing method, wherein the outer bushing is leak-free and reliably adheres to the cage during the process.

[0009] According to the present invention, a hydraulic bushing is provided, comprising an outer bushing, a support core, an elastomer disposed between the outer bushing and the support core and defining at least two fluid-filled chambers, and a cage vulcanized within the elastomer and having at least one annular end piece having an outer peripheral side, wherein the outer peripheral side of the at least one end piece includes two support portions extending circumferentially, and a retraction portion is formed between the support portions relative to an imaginary straight line connecting the two support portions as a tangent, wherein the two support portions are subjected to a radially inward preload by the outer bushing.

[0010] By designing the end piece or cage ring according to the invention to have two support portions, the outer bushing, which can be made of metal material, now has a reduced diameter deformation at its axial end (possibly with rolled edges). The cage may have only two supports on at least one of its two end pieces, preferably two supports on each end piece. The two circumferentially extending supports on one end piece are axially spaced apart. Cage deformation caused by further diameter reduction deformation of the outer bushing can be within small tolerances and can be easily calculated. The outermost second support can, as specified, contact or be pre-tightened by the outer bushing after further diameter reduction deformation, thereby maintaining a small specified deformation tolerance chain for the final cage geometry.

[0011] This differs from existing hydraulic bushings and their manufacturing methods. Previously, the cage was used as a bending clamp during the outer bushing crimping process and was therefore designed to be made of metal. This invention abandons this approach because the cage is no longer used as a bending clamp. The outer bushing bending radius that occurs during diameter reduction deformation can be freely found during the deformation process. For this purpose, the cage has the two support portions that define the characteristic of the cage being tightly fitted or abutting against the outer bushing. Here, the support can be achieved directly through direct contact between the outer bushing and the corresponding support portion, or indirectly, for example, by means of an elastomeric layer disposed between them.

[0012] Therefore, a space is formed radially inside the straight line that serves as the tangent, and this space is free of end-piece or cage material. This space can be defined by the straight line that serves as the tangent and the surface of the end-piece. The straight line that serves as the tangent is not radially interrupted and / or tangent to the end-piece protrusion or forming portion (Ausformung).

[0013] Therefore, three advantages are unexpectedly achieved simultaneously. First, the clamping force between the outer bushing and the cage can thus be large enough to suppress the aforementioned causes of accidents. Second, it is thus possible to control the cage's fit to the outer bushing profile when it deforms due to diameter reduction. Third, inaccuracies in the shape and position of the bushing components and inaccuracies in the vulcanization process can be plugged or compensated by the structure of the present invention. Any surface irregularities that the outer bushing may have on the cage or its end pieces, and thus tend to leak, are therefore irrelevant, as two designated support points are provided.

[0014] It is conceivable that in one design of the hydraulic bushing, the cage is constructed of either plastic or cast metal. Since the cage no longer functions as a bending clamp and no longer needs to resist forces during diameter reduction deformation to the same degree, it can be made of plastic and / or structurally designed to be more slender than has been done previously. Plastic is lighter and cheaper than commonly used metals. Therefore, plastic cages offer significant advantages over metal cages in this respect. Preferably, two support points are provided at each of the two axial ends, which can optionally be configured as mirror symmetrical about the transverse center plane.

[0015] It is conceivable that in a design of a hydraulic bushing, the outer diameters of the support portions of one end member, preferably two end members, are different. Preferably, the outer diameter of the axially inner support portion is larger than the outer diameter of the axially outer support portion. This allows for a particularly simple influence on the contact behavior and bending radius of the outer bushing during manufacturing. It is conceivable that the outer diameter of one support portion of the end member is 1.01 to 1.2 times, preferably 1.05 to 1.1 times, larger than the outer diameter of its respective other support portion. This allows for the cage to be securely and reliably held in place by means of the outer bushing.

[0016] According to an improved embodiment of the hydraulic bushing, only two support portions and / or two support portions on the at least one end piece can be pre-tightened by the outer bushing to contact the outer bushing. Alternatively or additionally, a support portion of an end piece may consist of two shaped portions or two protrusions or one shaped portion or one protrusion. The shaped portions may be, for example, end-side edge regions of the end piece, which may not extend radially outward, and the protrusions may be, for example, radially outward-extending end piece segments. On the at least one end piece, the outer bushing can therefore abut or pre-tighten only two support portions, resulting in reliable abutment as specified. This advantageous abutment behavior cannot be guaranteed when the end piece has more than three support portions. It is less reliable with only one support portion. However, this does not preclude the outer bushing from also pre-tightening against at least one elastomeric protrusion that may be present on the end piece.

[0017] It is conceivable that in one design of a hydraulic bushing, the molded portion and / or bulge is designed to be made of the same material as the end piece and / or cage and / or be a single piece. Thus, the cage can be manufactured in a simple, one-piece manner, preferably by injection molding or die casting.

[0018] It is conceivable that in one design of a hydraulic bushing, the tip of the support portion has an axial distance between each other that is between 0.2 and 1.0 times, preferably between 0.5 and 0.8 times, the axial extension dimension of the corresponding end piece. Such an axial distance between the two support portions results in two distinctly separate support portions for the outer bushing and prevents random contact in the event that the support portions are too close together.

[0019] According to an improved embodiment of the hydraulic bushing, at least one support portion, preferably two support portions, and / or the retraction portion can be radially and externally covered by an elastomer cover. The cover can also be another elastomer separate from the elastomer. Thus, although the two support portions no longer directly contact the outer bushing, they still support the outer bushing. The cover, which may be located between them, does not alter the purpose and function of the support portions due to its higher elasticity compared to the cage. The cover is particularly useful for the sealing of the bushing and / or compensation for unevenness. Advantageously, a larger tolerance range can be selected for the cage, support portions, and / or outer bushing. The cover can, for example, occupy or leave space between the support portions. In the latter case, a cavity can be formed into which the incompressible elastomer can displace when the outer bushing is placed on the cage and deforms by reducing its diameter.

[0020] According to an improved embodiment of the hydraulic bushing, the cover may include at least one elastomeric ridge extending circumferentially. The elastomeric ridge extends radially outward. The elastomeric ridge may be longitudinally positioned between the two support portions. Such an elastomeric ridge is used for specified clamping points and larger covers. This allows for new cage designs that enable multiple covers of the cage and outer bushing without significant cage deformation. This facilitates sizing speed (Kalibrierate).

[0021] According to an improved embodiment of the hydraulic bushing, the outer bushing can be a chamfered and / or anglerolled outer bushing. The reduction in diameter at at least the axial end results in cage clamping. Especially in conjunction with different outer diameters at two adjacent support locations, even a more flexible plastic cage, but perhaps also a brittle cast cage, can be reliably held. The diameter reduction deformation can be achieved using a sizing tool. The sizing tool serves two functions. On the one hand, the outer bushing diameter is reduced at least at its axial end, which extends the elastomer's lifespan in use. The diameter reduction can be, for example, at least 1 mm. On the other hand, the chamfer of the outer bushing at the corresponding location is obtained through the bevel of the sizing tool. The purpose is to securely position the cage and outer bushing and thus provide sufficiently large resistance to prevent relative axial displacement between the cage and outer bushing.

[0022] According to an improved version of the hydraulic bushing, the radial distance between the radially inner end of the outer bushing and one of the two support portions can be in the range of 0.5 mm to 4.0 mm, preferably in the range of 2.0 mm to 3.0 mm. This radial distance preferably exists between the radially inner end of the outer bushing and the axially inner support portion. Similarly, a radial distance of the same size can be defined between the radially inner end of the outer bushing and the inner circumferential surface at the maximum inner diameter of the outer bushing. Significantly improved and stronger clamping can be achieved with this invention. That is, the reduction in the diameter of the axial end can be done to a significantly greater extent than previously possible.

[0023] It is conceivable that in the design of a hydraulic bushing, the outer bushing, in its state before diameter reduction deformation, has an outer diameter at at least one axial end in the range of 70 mm to 85 mm, and in its state after diameter reduction deformation, has an outer diameter at at least one axial end in the range of 63 mm to 78 mm. It is conceivable that the outer diameter of the at least one axial end after diameter reduction deformation corresponds to 0.8 to 0.95 times, preferably 0.9 times, the outer diameter of the axial end of the outer bushing before diameter reduction deformation. Therefore, with the aid of the present invention, the outer diameter of the axial end of the outer bushing can be reduced by more than 10%, resulting in strong clamping.

[0024] According to an improved embodiment of the hydraulic bushing, the cage may have two annular end pieces, longitudinally spaced and connected by at least one web, preferably interconnected by two circumferentially spaced webs, wherein the at least one web preferably has a radially projecting radial web. Preferably, each of the two webs has a radial web. The radial web can abut against the inner circumferential surface of the outer bushing and create a sealed partition of a channel extending along the entire web and connecting the fluid cavities. The channel may be a separate channel extending to the left and right of the radial web, but it may also be a single channel extending along its circumferential extension sometimes to the left and sometimes to the right of the radial web. It is also feasible to provide at least one valve isolating the fluid cavities on the left and / or right sides of the radial web. Sealing on the outer circumferential side of the radial web may be meaningful for the desired bushing functionality, as undesirable fluid leakage may lead to changes in the damping or shock absorption characteristics of the bushing in the event of insufficient sealing. By abutting the outer bushing against the support portion during diameter reduction deformation at at least one axial end, the abutment of the at least one radial web against the outer bushing can be advantageously controlled. This is feasible because the bending performance of the web bearing the radial web during diameter reduction deformation can be influenced by the design of the support portion. Depending on which of the two support portions at one axial end bears the radially inward pressure more strongly, the web and consequently the radial web displace radially. If, for example, the axially outer support portion has a greater radial force than the axially inner support portion, this causes the web to bend radially outward. Consequently, the radial web may withstand a higher load than the seal of the isolation channel and / or isolation cavity. If, for example, the axially inner support portion has a greater radial force than the bearing's outer support portion, this causes the web to bend radially inward. Consequently, the radial web can withstand a smaller load than the seal of the isolation cavity. With this structure, internal leakage between damping channel sections or between fluid cavities can be prevented, while simultaneously controlling the abutment of the radial web against the outer bushing. The radial web can indirectly abut the inner circumferential surface of the outer bushing via an elastomeric interlayer to achieve a reliable leak-free seal, as the elastomeric interlayer improves the sealing performance for fluid isolation. The elastomeric interlayer can be designed to be integral with an elastomer.

[0025] According to the present invention, a method for manufacturing a hydraulic bushing, preferably a hydraulic bushing according to this document, is also provided, wherein the method comprises at least the following steps:

[0026] - Provide a first component comprising: a support core, an elastomer at least partially disposed on the circumferential side of the support core, and a cage vulcanized in the elastomer and having at least one annular end piece having an outer circumferential side, wherein the outer circumferential side of the at least one end piece includes two support portions extending circumferentially, forming a retraction portion between the support portions relative to an imaginary straight line connecting the two support portions as a tangent, wherein the two support portions can be preloaded radially inward by the outer bushing;

[0027] - A second component is provided, which includes an outer bushing;

[0028] - The first and second components are thus axially adjusted relative to each other, i.e., the outer bushing is arranged on the circumferential side of the first component;

[0029] - The diameter reduction deformation covers at least the axial end of the outer bushing surrounding at least one annular end piece.

[0030] Using this method, a high-performance bushing can be provided in a simple and inexpensive manner. Similarly, the advantages of this method already described regarding bushings are hereby pointed out.

[0031] According to an improved version of this method, the diameter reduction deformation can include, in sequence:

[0032] - A force is applied radially to the axially inner support portion, i.e., the at least one radial web is spaced apart from the inner circumferential surface of the outer bushing.

[0033] - Force is applied radially to the axially outer support portion such that at least one radial web directly or indirectly abuts the inner circumferential surface of the outer bushing.

[0034] Thus, the fluid cavities can be reliably and sealingly separated from each other without applying excessive force to the cage. Preferably, the two axially inner support locations can be stressed simultaneously. Alternatively or additionally, the same applies to the axially outer support locations. The contact of the radial web can be easily controlled by the applied force. Similarly, the advantages already described with respect to the bushings are also indicated here. Attached Figure Description

[0035] Other features, details, and advantages of the invention are derived from the wording of the claims and the following description of the embodiments in conjunction with the figures, wherein:

[0036] Figure 1 A perspective view of the cage of the present invention is shown.

[0037] Figure 2 A longitudinal perspective view of the bushing of the present invention is shown.

[0038] Figure 3 A longitudinal cross-sectional view of the bushing of the present invention according to other embodiments is shown.

[0039] Figure 4 Showing according to Figure 3 A longitudinal section view of the bushing misaligned by 90°.

[0040] Figures 5a to 5e This illustrates different process states of diameter reduction deformation in the bushing of the present invention.

[0041] Figures 6a to 6e This illustrates different stages of diameter reduction deformation in a bushing with only one support.

[0042] Figure 7 Showing according to Figure 4 Detailed images,

[0043] Figure 8 Detailed drawings of bushings in other embodiments are shown, and

[0044] Figure 9 Showing according to Figure 2 Detailed view of the bushing.

[0045] List of reference numerals

[0046] 2. Bushing

[0047] 2' bushing

[0048] 4 Outer bushing

[0049] 4' Outer bushing

[0050] 6 Support Core

[0051] 8. Elastomers

[0052] 10 cavities

[0053] 12 cavities

[0054] 14 cages

[0055] 14' cage

[0056] 16-terminal component

[0057] 18 Webs

[0058] 18' web

[0059] 20 Peripheral side

[0060] 22. Elevation

[0061] 23 Molding Section

[0062] 23' Molding section

[0063] 24. Elevation

[0064] 26 Retraction section

[0065] 28 Covering section

[0066] 30. Elastomer bulge

[0067] 32. Elastomer bulge

[0068] 34 Radial Web

[0069] 34' radial web

[0070] 36 Inner circumferential surface

[0071] 36' inner circumference

[0072] 38 channels

[0073] 40 valve

[0074] 42 tools

[0075] 44 bevel

[0076] A1 Axial distance

[0077] A2 Axial Extension Dimension

[0078] AV local V

[0079] AVII (Partial VII)

[0080] B1 Curved Line

[0081] B1' Curved line

[0082] B2 Curved Line

[0083] D Radial distance

[0084] G (straight line)

[0085] L longitudinal

[0086] R radial

[0087] U Zhou Xiang

[0088] Z-center longitudinal axis Detailed Implementation

[0089] In the figures, identical or corresponding components are labeled with the same reference numerals and therefore are not described again unless inappropriate. Features already described are not described again to avoid duplication and can be applied to all components with the same or corresponding reference numerals unless explicitly excluded. The disclosure contained throughout the description is applicable to the same components with the same reference numerals or the same component names. Locational descriptions chosen in the specification, such as upper, lower, and side, also apply to the figures immediately described and shown, and are applied accordingly to new locations when their positions change. Furthermore, individual features or combinations of features from the different embodiments shown and described can be independently, inventive, or solutions according to the invention.

[0090] Figure 1 A cage 14 consisting of a bushing 2 made of plastic material is shown separately. The cage 14 is traversed longitudinally by a central longitudinal axis Z in the longitudinal direction L and includes two annular end members 16, each having an outer peripheral side 20 and spaced apart in the longitudinal direction L. The two end members 16 are interconnected by two webs 18, wherein the webs 18 are opposed about the central longitudinal axis Z, or spaced 180° apart in the circumferential direction U about the central longitudinal axis Z. Each of the two webs 18 has a radially outwardly extending radial web 34. At each of its two end members 16, the cage 14 has two support portions extending circumferentially. Figure 1 The support portions of the cage 14 shown are designed as ridges 22 and 24. These support portions are adjacent to each other in the longitudinal direction L and therefore have an axial distance. Thus, an axially outer support portion or ridge 22 and an axially inner support portion or ridge 24 are formed on each axial end of the cage 14. The cage 14, along with the end members 16, web 18, radial web 34, and support portions, are manufactured as a single piece using uniform materials. A retractable portion 26 is formed between the two support portions. Figure 2 It is shown in the context of the fabricated bushing 2.

[0091] Figure 2 The bushing 2 also includes an outer bushing 4, a hollow support core 6 preferably made of aluminum alloy, and an elastomer 8. The elastomer 8 is disposed between the outer bushing 4 and the support core 6 and defines two fluid-filled cavities 10, 12. The cage 14 is vulcanized into or onto the elastomer 8. Figure 2 The support portion of the cage 14 shown is designed as an axially outwardly shaped part 23 and an axially inwardly raised part 24.

[0092] Figure 3 and Figure 4 Two cross-sectional views of the same bushing 2 are shown, in which, Figure 3 The cross section extends through the web 18. Figure 4The cross-section is offset by 90° about the central longitudinal axis Z. The radial web 34 presses against the inner circumferential surface 36 of the outer bushing 4 so that the fluid separates the two chambers 10, 12, the two valves 40, and two sections of the same channel extending not only on the left side of the radial web 34 but also on the right side (e.g., because it extends multiple times around the bushing with a channel shell insert not shown). The two ends 16 are configured in a mirror-symmetric manner about the transverse central plane, wherein, as Figure 1 The cage 14 shown is in Figure 3 and Figure 4 It is depicted in the middle. Figure 3 The local AV in the image is used as a detail image. Figures 5a to 5e It is shown in the middle, and Figure 4 Partial AVII in the drawing is used as a detail drawing. Figure 7 It is shown in the middle.

[0093] Figures 5a to 6e The curves from the FE simulation show the different deformation states of the outer bushings 4 and 4' and the cages 14 and 14'. For example... Figures 5a to 6e The local area shown corresponds to according to Figure 3 Local AV. In Figures 5a to 5e The image shows a cage 14 with a web 18 for the bushing of the present invention, which includes two support portions (protrusions 22, 24) on each end member 16, while for comparison, Figures 6a to 6e The bushing 2' with cage 14' is depicted, each end having only a single support portion (molded part 23') for the outer bushing 4'. Additionally, Figures 5a to 6e The outer bushings 4, 4' and the tool 42 with the bevel 44 are shown. The tool 42 may be a sizing tool. Figures 6a to 6e This is for comparison only and is not covered by the present invention. Elastomer components in Figures 5a to 6e The reason for this has been omitted to better explain the situation.

[0094] Figure 5a and Figure 6a The diagram shows the state before the diameter reduction deformation. In this state, the cylindrical outer bushings 4, 4' each have an initial diameter at their ends. This is positioned on their circumferential sides after axial movement relative to the cages 14, 14'. Preferably, the outer bushings 4, 4' and the cages 14, 14' or their first assembly are centered in the longitudinal direction L. The tool 42 reduces the end diameters of the outer bushings 4, 4' by deformation.

[0095] exist Figure 5b and Figure 6b As can be seen, tool 42, with its inclined surface 44, presses the outer bushings 4, 4', or their end edges towards the central longitudinal axis Z. Thus, in Figure 5b In the middle, the outer bushing 4 is supported on the axially inner protrusion 24, and its outer diameter is larger than that of the axially outer protrusion 22. Therefore, in Figure 6b In the middle, the outer bushing 4' is supported on the single molded part 23'. Figure 5b and Figure 5c or Figure 6b and Figure 6c During the process, it can be seen that the webs 18, 18' are bent inward by the applied force along the radial direction R, which is visualized by the bending lines B1, B1'. The bending also causes the radial webs 34, 34' to be spaced apart from the outer bushings 4, 4' in the radial direction R. A distance is now formed between the outer bushings 4, 4' and the distal ends of the radial webs 34, 34'. Therefore, the radial webs 34, 34' cannot be tightly abutted against the inner circumferential surfaces 36, 36' of the outer bushings 4.

[0096] exist Figure 5d In the middle, the outer bushing 4 is deformed at the end side such that its inner circumferential surface 36 is now also supported on the axially outward protrusion 22. Figure 6d In this case, the inner circumferential surface 36' now rests on the larger surface of the end piece of the cage 14', where the support portion remains unchanged in principle and is still in the only support portion. In the bushing 2 of the invention, the axially outward support portion 22 now has a greater radial force than the axially inward support portion 24 by a further reduction in diameter. This causes the web 18 to bend radially outward, as shown by the bend line B2. The bend according to B2 can only be achieved through the second support portion, which, together with another support portion, clamps the retracted portion 26. The bend of the web 18' according to bend line B2 is therefore not even possible in the cage 14'.

[0097] exist Figure 5e The diagram shows that as the radial diameter of the web 34 further decreases, the outer bushing 4 approaches and eventually fits tightly against its inner circumferential surface 36 as specified. The two support locations are indicated by a radially inward preload from the outer bushing 4. Figure 6e This demonstrates that it is even impossible to achieve with insufficient support and that a distance remains between the outer bushing 4' and the radial web 34', leading to internal leakage. FE results in Figure 6e The diagram shows the cage 14' being lifted away from the outer bushing 4' within the desired chamber partition area. The result is the damping loss within the hydraulic damping system.

[0098] By designing the cage 14 according to the invention to have two support portions at each end member 16, the outer bushing 4, upon deformation or crimping, is directed to only abut against the innermost support portion. The deformation of the cage 14 caused by further deformation of the outer bushing 4 can be controlled within small tolerances and is easily calculated. The further outer second support portion is strictly in contact after further deformation or crimping of the outer bushing 4, thereby maintaining a small deformation tolerance chain that defines the final cage geometry.

[0099] Figures 7 to 9The end pieces 16 of the cage 14 in the installed state after diameter reduction deformation are shown in different designs. It can be seen that the two support portions or their distal points or tips are connected to each other by a straight line G as a tangent. The retracted portion 26 now retracts about this straight line G and is defined in the longitudinal direction L by the two support portions.

[0100] exist Figure 7 In this configuration, the support portion is designed with bulges 22 and 24 and is covered radially outward by a cover portion 28 of the elastomer 8. This does not impede the advantageous function of the two support portions but results in a sealed bushing 2. The end member 16 is designed as a wedge shape in longitudinal section. The retracted portion 26 is filled with an elastomer, but the radially inward force exerted by the elastomer does not adversely affect the advantageous flexural elasticity of the web 18. The cover portion 28 includes two elastomer bulges 30 and 32 that extend radially outward and cover the outer bushing 4. The bulges 22 and 24 now indirectly bear the force exerted by the outer bushing 4 through the cover portion 28.

[0101] This invention allows for relatively large end-side deformation of the outer bushing 4, which results in the cage 14 and the outer bushing 4 being fixed in place, and consequently, provides sufficiently large resistance to prevent axial displacement of the cage 14 and the outer bushing 4. The radial distance D can be defined between the radially inner end side of the outer bushing 4 and the inner circumferential surface 36 of the outer bushing 4 at its maximum inner diameter location. Therefore, with the aid of this invention, the outer diameter of the axial end of the outer bushing 4 can be reduced by more than 10%, resulting in a strong clamping force, which can be represented, for example, by the radial distance D.

[0102] exist Figure 8 The diagram also shows two protrusions 22 and 24 as support points, but they are only covered by a thin cover 28 on their radially outer side. The end member 16 is designed in a C-shape in longitudinal section. These two support points, or their radially distal points or distal tips, are spaced apart by an axial distance A1 in the longitudinal direction L. These points or tips are subjected to force. The corresponding end member 16 has an axial extension dimension A2 in the longitudinal direction L, where the axial extension dimension A2 is the length of the end member 16 along the longitudinal direction L.

[0103] In the example Figure 2 local Figure 9 In the middle section, the axially outer support portion is formed as the molding part 23, and the axially inner support portion is shown as the protrusion 24. The end member 16 is designed as an L-shape in longitudinal section.

[0104] This invention is not limited to the embodiments described above, but can be modified in a variety of ways. All features and advantages derived from the claims, specification, and figures, including structural details, spatial arrangements, and method steps, are important to the invention not only individually but also in various different combinations.

[0105] All combinations consisting of at least two features disclosed in the specification, claims and / or figures fall within the scope of this invention.

[0106] To avoid duplication, features disclosed in relation to the apparatus should also be considered as disclosed in relation to the method and are therefore subject to protection. Similarly, features disclosed in relation to the method should be considered as disclosed in relation to the apparatus and are therefore subject to protection.

Claims

1. A hydraulic bushing comprising an outer bushing (4), a support core (6), and a cage (14), and an elastomer (8) disposed between the outer bushing (4) and the support core (6), the elastomer (8) defining at least two fluid-filled chambers (10, 12), the cage (14) being vulcanized within the elastomer (8) and having at least one annular end piece (16) with an outer peripheral side (20), characterized in that, At least one end piece (16) has an outer peripheral side (20) comprising two support portions extending circumferentially, with a retracted portion (26) formed between the support portions relative to an imaginary straight line (G) connecting the two support portions as a tangent, wherein the two support portions are preloaded radially inward by the outer bushing (4), wherein the two support portions on the at least one end piece (16) are preloaded only by the outer bushing (4), and wherein the outer diameters of the support portions of the end piece (16) are different. The retractable portion (26) is radially externally covered by the covering portion (28) of the elastomer (8). The cover (28) includes at least one elastomeric ridge (30, 32) extending circumferentially. The elastomer protrusions (30, 32) are arranged longitudinally between the two support portions.

2. The hydraulic bushing according to claim 1, characterized in that, On at least one end piece (16), only these two support portions are pre-tightened and / or in contact with the outer bushing (4), and / or the support portions are composed of two molded portions (23) or two protrusions (22, 24) or one molded portion (23) and one protrusion (22, 24).

3. The hydraulic bushing according to any one of the preceding claims, characterized in that, At least one support portion is covered radially outward by a cover portion (28) of the elastomer (8).

4. The hydraulic bushing according to claim 1, characterized in that, The outer bushing (4) is a rolled and / or rolled outer bushing (4).

5. The hydraulic bushing according to claim 1, characterized in that, The radial distance (D) between the inner radial end of the outer bushing (4) and one of the two support parts is in the range of 0.5 mm to 4.0 mm.

6. The hydraulic bushing (2) according to claim 1, characterized in that, The cage (14) has two annular end pieces (16) that are spaced apart in the longitudinal direction (L) and connected to each other by at least one web plate (18).

7. The hydraulic bushing according to claim 1, characterized in that, The two support portions and / or the retractable portion (26) are covered radially outward by the cover portion (28) of the elastomer (8).

8. The hydraulic bushing according to claim 5, characterized in that, The radial distance (D) between the inner radial end of the outer bushing (4) and one of the two support parts is in the range of 2.0 mm to 3.0 mm.

9. The hydraulic bushing (2) according to claim 6, characterized in that, The two annular end pieces (16) are connected to each other by two webs (18) spaced apart in the circumferential direction (U).

10. The hydraulic bushing (2) according to claim 6, characterized in that, The at least one web (18) has a radially projecting (R) web (34).

11. A method for manufacturing a hydraulic bushing (2), characterized in that, a. Provide a first component comprising: a support core (6), an elastomer (8), and a cage (14) vulcanized within the elastomer (8), the elastomer (8) being at least partially disposed on the circumferential side of the support core (6), the cage (14) having at least one annular end piece (16) having an outer circumferential side (20), wherein the outer circumferential side (20) of at least one end piece (16) includes two support portions extending in the circumferential side, a retraction portion (26) being formed between the support portions relative to an imaginary straight line (G) connecting the two support portions as a tangent, wherein the two support portions can be preloaded radially inward by an outer bushing (4); b. Provide a second component, the second component including an outer bushing (4); c. Adjust the first component and the second component axially relative to each other so that the outer bushing (4) is arranged on the circumferential side of the first component; d. The outer bushing (4) is deformed to reduce the diameter of at least the axial end of the at least one annular end piece (16), wherein the two support portions on the at least one end piece (16) are pre-tightened only by the outer bushing (4), and wherein the outer diameters of the support portions of the end piece (16) are different. The retractable portion (26) is radially externally covered by the covering portion (28) of the elastomer (8). The cover (28) includes at least one elastomeric ridge (30, 32) extending circumferentially. The elastomer protrusions (30, 32) are arranged longitudinally between the two support portions.

12. The method for manufacturing a hydraulic bushing (2) according to claim 11, characterized in that, The diameter reduction deformation includes, in sequence: a. Apply a force to the axially inner support portion in the radial direction (R) such that at least one radial web (34) is moved away from the inner circumferential surface (36) of the outer bushing (4). b. Apply a force to the axially outer support in the radial direction (R) such that the at least one radial web (34) directly or indirectly abuts the inner circumferential surface (36) of the outer bushing (4).

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