Bearing bushing comprising a stopper with an external elastomer track

Abstract

The invention relates to a bearing bushing (1), in particular a hydraulic bearing, for mounting a vehicle part on a vehicle body, comprising a core (2) extending along a central longitudinal axis (Z) of the bearing bushing (1), and an outer sleeve (3) surrounding the core (2) in the circumferential direction (U), wherein a spring element (4) is arranged between the core (2) and the outer sleeve (3), and wherein the bearing bushing has at least one stopper half-shell (6) in a load path between the core (2) and the outer sleeve (3). The bearing bushing (1) is characterized in that an elastomer track (7) is arranged on an outer lateral surface (9) of the at least one stopper half-shell (6).

Description

[0001] According to the preamble of claim 1, the invention relates to an elastomeric bearing bushing.

[0002] Elastomeric bushings of the type mentioned above are used as chassis or engine mounts in motor vehicles to improve ride comfort, for example by damping forces or shocks that can occur when driving over uneven surfaces, or by isolating vibrations introduced by driving. A conventional bushing has a core, an outer sleeve surrounding the core circumferentially, and a spring element connecting the core and the outer sleeve, at least partially.

[0003] A special type of bearing bushing is the so-called hydraulic bearing. It has at least two separate fluid chambers, which are usually connected to each other by fluid-communicating channels. Hydraulic bearings also include half-shell-like stoppers, which are geometrically defined, for example by a cage in the bushing, and which serve on the one hand to limit the radial deflection of the core, and on the other hand, in some embodiments, can form the damping channels between the fluid chambers.

[0004] Hydraulic mounts, especially radially damping hydraulic mounts, are widely known. They are used, for example, for mounting chassis components. Their purpose is to dampen dynamic forces occurring during braking and acceleration as much as possible.

[0005] For example, CN 211117332 U describes a hydraulic bearing with a core and an outer sleeve, wherein two stopper half-shells are arranged between the core and the outer sleeve. These stopper half-shells have an elastomer track on their inner surface (i.e., on the side facing the core). When torsional and radial loads are superimposed, such that the radial load brings the elastomer track of the stopper half-shells into contact with the core, the elastomer track on the half-shell side is not only compressed but also subjected to tribological stress. This stress can lead to increased wear of the elastomer track on the half-shell side and thus to premature failure of the entire hydraulic bearing. Furthermore, the elastomer track must be applied to the inner surface of the half-shell by means of vulcanization, which requires an adhesion promoter. This process is time-consuming and expensive.

[0006] The object of the invention is therefore to eliminate the disadvantages in the prior art and to create a bearing bushing that is more cost-effective and robust compared to previously known solutions.

[0007] The main features of the invention are specified in claim 1. Specific embodiments of the invention are the subject of claims 2 to 18.

[0008] The problem is solved according to the main claim by a bearing bushing, preferably a hydraulic bearing, for mounting a vehicle component on a vehicle body, wherein the bearing bushing comprises a core extending along a central longitudinal axis of the bearing bushing and an outer sleeve circumferentially surrounding the core, wherein a spring element is arranged between the core and the outer sleeve, and wherein the bearing bushing has at least one stopper half-shell in a load path between the core and the outer sleeve. The bearing bushing is characterized in that an elastomer track is arranged on an outer lateral surface of the stopper half-shell.

[0009] The spring body is made of an elastomeric material and encompasses at least part of the core of the bearing bushing, with the spring body being bonded to the core by a material bond. It is also conceivable that the spring body completely encloses the bearing core. In this case, the spring body can be vulcanized to the core.

[0010] According to the invention, the elastomer track of the bushing is not applied to the core-facing side of the stopper half-shell, but rather to the side of the stopper half-shell facing the outer sleeve. In this case, the elastomer track can also be referred to as an outer progression cushion. An elastomer track arranged on the outside of the stopper half-shell has the advantage that even in the event of a loss of adhesion between the stopper half-shell and the elastomer track, the elastomer track can hardly slip, since it is clamped, at least partially, between the stopper half-shell and the outer sleeve. It was also found that thermoplastic elastomers (TPE) can be used to produce the elastomer track, which are injection-molded onto the outer surface of the stopper half-shell using a two-component process.This finding is surprising because TPEs can typically experience a loss of adhesion in the presence of glycol, which is regularly used as a working fluid in hydraulic bearings, as well as under temperature influence. However, due to the inventive fixed arrangement of the track by means of form and / or force fit, a material-bonded adhesion of the elastomer track to the outer surface of the stopper half-shell is no longer permanently necessary, but offers advantages, especially during the assembly of the half-shell in the bearing.

[0011] According to a further development, the at least one stopper half-shell can be a component separate from the core and the outer sleeve, which is received in a cavity between the core and the outer sleeve, wherein the stopper half-shell is, in particular, completely contained within the cavity. A bearing bushing with separately manufactured stopper half-shells, subsequently mounted in the bushing, is characterized by greater design freedom with regard to geometry compared to bearing bushings with one-piece molded half-shells. Furthermore, separate manufacturing has the advantage that the stiffness of the elastomer track on the outer surface of the stopper half-shell can be selected independently of the stiffness of the spring element. In addition, a different polymer can be used for the elastomer track than for the spring element.For example, a natural rubber-based elastomer can be used for the spring body, while a thermoplastic elastomer can be used for the elastomer track on the stopper half-shell. Manufacturing components from thermoplastic elastomers can enable significantly shorter cycle times than are achievable with chemically crosslinking elastomers, such as those based on natural rubber.

[0012] According to a further development, it can be provided that the outer surface of the at least one stopper half-shell is essentially completely covered by the elastomer track. This simplifies the manufacturing of the elastomer stopper half-shell component. Furthermore, a complete coating of the outer surface with elastomer reduces the risk of the elastomer track slipping on the stopper half-shell in the event of a loss of adhesion.

[0013] Preferably, the elastomer track can be applied as a continuous and essentially planar layer to the outer surface of the half-shell, so that a single injection point is sufficient to manufacture the elastomer track.

[0014] According to a further development, the elastomer track can be designed to bear against an inner surface of the outer sleeve, at least in sections. This clamps the flat elastomer track, at least in sections, between the outer surface of the stopper half-shells and the inner surface of the outer sleeve, thus preventing or significantly reducing any unintentional displacement or slippage of the elastomer track relative to the stopper half-shell. Because the elastomer track of the stopper half-shell bears against the inner surface of the outer sleeve and not against another, more inwardly directed surface, such as an intermediate tube, the circumferential extent of the stopper half-shell, and thus the area of ​​the elastomer track, can be made particularly large. A large area, in turn, leads to lower pressures for a given force, consequently to lower stress, and ultimately to a particularly long service life.In other words: the further away the elastomer track is placed from the center of the bearing, the more robust it is.

[0015] According to a further development, the elastomer track can be materially bonded and / or form-fitted to the outer surface of the at least one stopper half-shell. A form-fit connection of the elastomer track to the outside of the stopper half-shell is created, in particular, when the elastomer track is clamped between the stopper half-shell and the outer sleeve. Material bonding can be achieved, for example, by a suitable adhesive and subsequent vulcanization, but preferably by two-component injection molding. Two-component injection molding is particularly advantageous in the case of the bearing according to the invention because the elastomer track, which is injected onto the outside of the half-shell, is held in position by its form-fit arrangement between the half-shell and the outer sleeve.This significantly reduces the risk of premature adhesion loss, which can otherwise occur due to contact between thermoplastic elastomer (TPE) and common damping media such as glycol or glycol-water mixtures. Nevertheless, the cost advantage of 2K injection molding compared to vulcanizing the elastomer track onto a half-shell can be realized.

[0016] According to further development, the elastomer track can be made of a thermoplastic elastomer. The use of TPE represents an advantageous alternative to natural rubber and can be easily applied to the outer surface of the stopper half-shell by injection molding. Because the elastomer track is applied to the outside of the stopper half-shell and can be clamped, at least partially, between the half-shell and the outer sleeve, the risk of premature loss of adhesion of the elastomer track to the half-shell is minimized. This can increase the service life of the entire bearing bushing.

[0017] According to further training, it is possible to manufacture the elastomer track and the stopper half-shell using 2K injection molding. This allows the stopper half-shell and the elastomer track to be produced in a single production step.

[0018] According to a further development, the outer surfaces of the stopper half-shell can be designed to be closed. For the purposes of this disclosure, "closed" means that the stopper half-shell has no radially extending through holes or openings, such as windows. A completely closed outer surface of the stopper half-shell increases the contact area between the outer surface and the elastomer track, thus reducing the stress on the adhesion zone and ultimately resulting in a more robust adhesion of the elastomer track to the outer surface. Furthermore, a completely closed outer surface minimizes unwanted slippage of the elastomer track on the stopper half-shell, which in turn counteracts premature wear of the bearing bushing.

[0019] If the bearing bushing is a hydraulic bearing with at least two fluid-filled fluid chambers (also called working chambers), the fluid chambers can be connected to each other via the pressure relief channel and / or a damping channel. During relative movement of the core to the outer sleeve, one of the two fluid chambers is compressed. This causes the fluid in the compressed chamber to flow through the channel into the other fluid chamber. This allows for a simple damping and / or vibration damping effect.

[0020] According to a further embodiment, the stopper half-shell may have at least one overpressure channel and / or at least one damping channel on its outer circumference. The at least one damping channel is preferably designed as a groove-like or channel-like recess, which is generally formed substantially circumferentially in the outer surface of the stopper half-shell. If the at least one overpressure channel or damping channel is formed in the outer surface of the stopper half-shell, a further embodiment may provide that it is at least partially lined or covered by the elastomer track. In particular, the at least one damping channel may be completely lined or covered by the elastomer track. The damping channel is then visible from the outside (i.e., when viewed from above on the elastomer-coated outer surface of the stopper half-shell) in the form of a groove-like recess in the elastomer track.The damping channel can also be left unlined or only partially lined with the elastomer track. A particular advantage is that, despite using identical stopper half-shells with identical grooves, the lining of these grooves with the elastomer track can be varied for different bearing configurations. Thus, the resulting cross-section of the fluid-conducting damping channel can be adjusted simply by modifying the elastomer lining, allowing the maximum damping of the hydraulic bearing to be easily adapted to different requirements, even when using identical parts such as the stopper half-shells.

[0021] According to a further development, the bearing bushing can be provided with two stopper half-shells. The stopper half-shells are preferably arranged in the bearing bushing such that they are diametrically opposed to each other. According to a further development, each stopper half-shell can have its own elastomer track on its outer surface. However, it can also be provided that only one of the two stopper half-shells has an elastomer track on its outer surface, and that the other stopper half-shell does not. Preferably, the stopper half-shell that would have to bear braking loads when the bearing bushing is installed in the vehicle as intended would have an elastomer track on its outer surface.

[0022] According to a further development, the bearing bushing can be provided with at least one elastomeric stop arranged on the core. The at least one stop advantageously serves to limit radial movement of the core and to minimize a knocking noise upon initial contact between the core and the stop half-shell. With sufficient radial movement of the core, the stop can strike the inner surface of the stop half-shell. The bearing bushing can also have two stop stops arranged diametrically opposite each other on the core. Each stop stop limits radial movement of the core in the direction of one of the stop half-shells, which are then preferably also present in pairs within the bearing bushing.

[0023] According to a further development, the core may be provided with at least one stopper pocket for receiving at least one elastomeric stopper. The stopper pocket ensures reliable fixation of the stopper to the core. The core's stopper pocket may be designed, in particular, to counteract circumferential movement of the stopper. For this purpose, the stopper pocket may, for example, include two longitudinal projections extending along the core, each bearing laterally against the stopper and thus serving as lateral stops for the stopper.

[0024] According to a further development, the bearing bushing can be a hydraulic bearing bushing, which can also be referred to as a hydraulic bearing or hydraulic bushing. Hydraulic bearings typically have two fluid chambers that are connected to each other via fluid-conducting channels. According to a further development, one or both fluid chambers of the hydraulic bearing can simultaneously function as a cavity in which at least one stopper half-shell is received, so that the stopper half-shell is completely surrounded by fluid.

[0025] According to further training, it can be provided that the fluid chamber in which at least one stopper half-shell is received is filled with a fluid that includes glycol.

[0026] Further features, details and advantages of the invention will become apparent from the wording of the claims and from the following description of exemplary embodiments with reference to the drawings: Fig. Figure 1 shows a schematic cross-section through a possible embodiment of the bearing bushing according to the invention; Fig. Figure 2 shows a schematic longitudinal section through another embodiment of the bearing bushing according to the invention.

[0027] In Fig. Figure 1 shows a schematic cross-sectional view of a possible embodiment of the bearing bushing 1 according to the invention, wherein the bearing bushing 1 is a hydraulic bushing. The section plane runs perpendicular to a central longitudinal axis Z of the bearing bushing 1. The Fig. The example shown in Figure 1 comprises a core 2 extending along the central longitudinal axis Z from a first end face 18 to a second end face 19 of the bearing bushing 1 (in Fig. (1 not shown). The core 2 is enclosed circumferentially U by an outer sleeve 3, the outer sleeve 3 having the form of a hollow cylindrical tube. The longitudinal axis of the hollow cylindrical tube formed by the outer sleeve 3 corresponds to the longitudinal axis Z of the bearing 1. The core 2 is arranged inside the outer sleeve 3 and is connected to the outer sleeve 3, at least partially, via a spring element 4. The bearing core 2 also has a recess 16 into which a fastening element can be inserted.

[0028] As the example in Fig. As can be seen in Figure 1, the spring element 4 formed between the core 2 and the outer sleeve 3 defines two cavities 8, each cavity 8 being a fluid chamber 14 filled with a liquid in the example shown. The fluid chambers 14 are fluidly coupled by a pressure relief channel 24. Such coupling can enable pressure equalization between the fluid chambers 14, for example, under shock loads. Furthermore, corresponding damping channels 11 can be formed in the half-shells.

[0029] The bushing 1 shown has two stopper half-shells 6a,b, each arranged in a load path between the core 2 and the outer sleeve 3. As shown in Fig. As can be seen in Figure 1, the outer surfaces 9 of the two stopper half-shells 6a,b are each completely covered by an elastomer track 7. The two elastomer tracks 7 lie on the outside of the stopper half-shells 6a,b, i.e., they are each located on the side of the stopper half-shells 6a,b facing away from the core 2 (or on the side facing the inner surface 10 of the outer sleeve 3).

[0030] The in Fig. The bearing bushing 1 shown comprises a cage 15 for the outer circumferential connection of the elastomer track 7. At the same time, the cage 15 provides circumferential guidance for the stopper half-shells 6a,b in the bearing bushing 1. The cage 15 is composed of a first support ring 21 and a second support ring 22 (in Fig. (1 not shown), which are connected to each other via axially extending webs 23. In the Fig. In section 1, only the webs 23 of the cage 15 are visible.

[0031] The in Fig. The example shown for a bearing bushing 1 also includes two stop blocks 12, each made of an elastomeric material. The stop blocks 12 limit the movement of the core 2 in the radial direction R by striking the inner surface of the respective stop block half-shell 6a,b when the core 2 moves sufficiently in the radial direction R. According to Fig. In the example shown, the two stop stoppers 12 are arranged diametrically opposite each other on the core 2, such that each stop stopper 12 limits the radial movement of the core 2 in the direction of one of the stopper half-shells 6a,b. The core 2 of the example shown has two stopper pockets 13 for receiving the stop stoppers 12. Each stopper pocket 13 includes two projections 17 extending longitudinally Z along the core 2 and projecting radially R, which act as lateral limits for the respective stop stopper 12 and thus protect the stop stopper from overload.

[0032] Fig. Figure 2 shows a schematic longitudinal section through another embodiment of the bearing bushing 1. The longitudinal section runs along the central longitudinal axis Z of the bearing bushing 1, which is also a hydraulic bushing.

[0033] As in Fig. As can be seen in Figure 2, the stopper half-shells 6a,b can have damping channels 11, with the example shown comprising one damping channel 11 per stopper half-shell 6a,b. The two damping channels 11 are designed as groove-like recesses, each extending circumferentially U in the outer lateral surfaces 6 of the stopper half-shells 6a,b. The damping channel 11 of stopper half-shell 6b is completely covered by the elastomer track 7. The damping channel 11 of stopper half-shell 6a has no elastomer coating and is therefore free of the elastomer track 7. By varying the elastomer lining of the groove, the cross-section of the damping channels 11 can be easily adapted to different requirements.

[0034] The elastomer track 7 applied to the stopper half-shell 6b also incorporates two pockets 20. The pockets 20 ensure that the elastomer track 7 does not lie completely against the inner surface 10 of the outer sleeve 3. This allows the corresponding stopper half-shell 6b some "play," enabling it to initially compress softly and, after the pockets are engaged, to exhibit a strongly progressive spring characteristic.

[0035] The in Fig. The longitudinal section shown in Figure 2 also shows the first support ring 21 and the second support ring 22 of the cage 15. The two stopper half-shells 6a,b are arranged between the two support rings 21, 22 and are thus received by the cage.

[0036] The invention is not limited to one of the embodiments described above, but can be modified in many ways.

[0037] All features and advantages arising from the claims, the description and the drawing, including design details, spatial arrangements and process steps, can be essential to the invention both individually and in various combinations. Reference symbol list 1 bearing bushing 2 cores 3 Outer sleeve 4 spring bodies 5 Load path 6a,b Stopper half shell 7 Elastomer track 8 Cavity 9 Outer surface 10 interior surface 11 Damping channel 12 stop blocks 13 stopper pockets 14 Fluid chamber 15 cage 16 recording 17 lead 18 First front 19 Second front 20 bags 21 First support ring 22 Second support ring 23 Bridge 24 Overpressure channel Z Central longitudinal axis R Radial direction U circumferential direction QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] CN 211117332 U

[0005]

Claims

[1] Bearing bushing (1) for supporting a vehicle part on a vehicle body, comprising a core (2) extending along a central longitudinal axis (Z) of the bearing bushing (1) and an outer sleeve (3) surrounding the core (2) in the circumferential direction (U), wherein a spring element (4) is arranged between the core (2) and the outer sleeve (3), and wherein the bearing bushing has at least one stopper half-shell (6) in a load path between the core (2) and the outer sleeve (3), characterized by , that an elastomer track (7) is arranged on an outer surface (9) of the at least one stopper half-shell (6). [2] Bearing bushing (1) according to claim 1, characterized by , that the at least one stopper half-shell (6) is a component separate from the core (2) and from the outer sleeve (3), which is received in a cavity (8) between the core (2) and the outer sleeve (3), wherein the stopper half-shell (6) is in particular completely received in the cavity (8). [3] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the outer surface (9) of the at least one stopper half-shell (6) is substantially completely covered by the elastomer track (7). [4] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the elastomer track (7) is at least partially in contact with an inner surface (10) of the outer sleeve (3). [5] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the elastomer track is connected to the outer surface (9) of the at least one stopper half-shell (6) in a material-bonded and / or form-bonded manner. [6] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the elastomeric track (7) comprises a thermoplastic elastomer. [7] Bearing bushing (1) according to any one of the preceding claims, characterized by, that the elastomer track (7) and the at least one stopper half-shell (6) are manufactured by means of 2K injection molding. [8] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the outer surface (9) of the at least one stopper half-shell (6) is closed. [9] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the at least one stopper half-shell (6) has at least one damping channel (11) on its outer circumference. [10] Bearing bushing (1) according to claim 9, characterized by , that the at least one damping channel (11) is at least partially lined by the elastomer track (7). [11] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the bearing bushing (1) has two stopper half-shells (6). [12] Bearing bushing (1) according to claim 11, characterized by , that each stopper half-shell (6) has a separate elastomer track (7) on its outer surface (9). [13] Bearing bushing (1) according to claim 11, characterized by , that only one of the stopper half-shells (6) has the elastomer track (7) on its outer surface (9), and that the other stopper half-shell (6) does not have an elastomer track. [14] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the bearing bushing (1) has at least one elastomeric stop (12) arranged on the core (2). [15] Bearing bushing (1) according to claim 14, characterized by , that the core (2) has at least one stopper pocket (13) for receiving the at least one elastomeric stopper (12). [16] Bearing bushing (1) according to any one of the preceding claims, characterized by , that the bearing bushing (1) is a hydraulic bearing. [17] Bearing bushing (1) according to claim 16, characterized by , that the cavity (8) in which the at least one stopper half-shell (6) is received is a fluid chamber (14) of the hydraulic bearing. [18] Bearing bushing (1) according to claim 17, characterized by , that the fluid chamber (14) in which the at least one stopper half-shell (6) is received is filled with a fluid comprising glycol.

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