Bearing sleeve for ball-and-socket joint, ball-and-socket joint, chassis assembly and method for producing bearing sleeve

Abstract

The invention relates to a bearing sleeve (2) for a ball joint (1), comprising a sleeve shell part (11) made of a first material, said sleeve shell part (11) forming a receiving space (6) in the shape of a truncated sphere for the articulated mounting of a joint ball (4), the inner side (12) of the housing part (11) has a coating made of a second material to form a sliding layer (13). In order to improve the sliding behavior between the joint ball (4) and the bearing sleeve (2) or to reduce friction, the bearing sleeve (2) is characterized in that the second material is parylene.

Description

TECHNICAL FIELD

[0001] The invention relates to a bearing cup for a ball joint, having a cup shell component made of a first material, wherein the cup shell component forms a spherical segment-shaped receiving space for the articulating movement of a joint ball, and the inner side of the cup shell component has a coating made of a second material to form a sliding layer. Furthermore, the invention also relates to a ball joint having such a bearing cup and to a chassis assembly having such a ball joint. Finally, the invention relates to a method for producing such a bearing cup. BACKGROUND

[0002] Such a bearing cup and a ball joint having such a bearing cup are known from the patent document DE 10 2010 037 586 A1. Therein, the second material consists of or contains zinc. It is also known there that a lubricant is used in the ball joint in order to reduce the friction between the joint ball and the bearing cup.

[0003] In particular in ball joints, for example in vehicle chassis, in addition to hydrodynamic sliding friction, there is also mixed friction and solid friction. During operation, in particular during slow movement, for example in view of a change in direction of the joint ball relative to the bearing cup, undesirable friction effects, in particular a loss of traction effect (Losbrech-Effekten) and / or a stick-slip effect (Ruckgleit-Effekten) can occur. This undesirable friction effect is due to the solid friction itself and the contribution of the solid friction to the mixed friction between the joint ball and the bearing cup. In addition to the use of a friction-reducing lubricant, therefore, it is also required that the material pairing of the friction partners, here the joint ball and the bearing cup, has a friction coefficient that is as low as possible. SUMMARY

[0004] On the basis thereof, it is an object of the invention to improve the bearing cup and / or the ball joint and / or the chassis assembly and / or the method of the kind given at the outset, in order to improve the sliding properties or to reduce the friction between the joint ball and the bearing cup. In particular, the bearing cup should on the one hand provide high strength and / or pressure resistance and on the other hand improved sliding properties and a reduced friction coefficient. Preferably, alternative embodiments should be provided.

[0005] The object of the invention is achieved by the bearing cup according to claim 1 and / or the ball joint according to claim 5 and / or the chassis assembly according to claim 7 and / or the method according to claim 8. Preferred refinements of the invention can be given by the dependent claims and the following description.

[0006] The bearing bush is used in a ball-and-socket joint. In particular, the ball-and-socket joint is used in a chassis assembly and / or a chassis of a vehicle. The bearing bush has a bush shell component made of a first material. Preferably, the bush shell component determines the contour or shape of the bearing bush. In particular, the bearing bush is formed by a single bush shell component. The bush shell component forms a spherical segment-shaped receiving space for the articulating joint ball. The bush shell component has an inner side. In particular, the inner side is at least partially spherical and / or is configured as a hollow spherical segment to form the spherical segment-shaped receiving space. The inner side of the bush shell component has a coating made of a second material for forming a sliding layer. In particular, the sliding layer is formed on the inner side of the bush shell component using the second material. Preferably, the entire inner side is covered with the sliding layer made of the second material. In particular, the inner side of the bush shell component has a single layer, and this layer is formed as a sliding layer from the second material. According to the application, the second material is Parylene.

[0007] The advantage is that the sliding properties of the bearing bush are improved due to the formation of the sliding layer made of Parylene. Thereby, the friction between the bearing bush and the joint ball can be reduced. In particular, a particularly thin sliding layer can be produced using Parylene.

[0008] According to another embodiment, the thickness of the sliding layer made of Parylene is less than 30 pm, or less than 20 pm, or less than 10 pm. Preferably, the thickness of the sliding layer made of Parylene is less than 5 pm, or less than 2 pm, or less than 1 pm.

[0009] Preferably, the second material Parylene is fluorine-containing. In particular, at least one hydrogen atom or a plurality of hydrogen atoms in each Parylene molecule is replaced by a fluorine atom. The use of fluorine-containing Parylene allows for a better reduction of the friction between the bearing bush and the joint ball.

[0010] The sliding layer made of Parylene can be applied to the inner side of the bush shell component by chemical vapor deposition. Thereby, a thin sliding layer made of Parylene can be produced, which can also be applied very uniformly to the inner side of the bush shell component.

[0011] Preferably, the bush shell component is completely coated with the second material Parylene. Thus, all surfaces of the bush shell component, in particular the outer side of the bush shell component facing away from the inner side, are coated with the second material Parylene. Although the sliding layer made of Parylene is only required at the inner side of the bush shell component, the production of the sliding layer is simplified and / or the sliding layer can be realized more cost-effectively by completely coating the bush shell component.

[0012] According to an improvement, the first material forming the sleeve part is a plastic material. The plastic material can be a non-reinforced plastic material or a reinforced plastic material. The reinforced plastic material can have a fiber reinforcement. In particular, the first material is a thermoplastic. Preferably, the first material is a POM (polyoxymethylene) plastic. Thus, a sufficiently strong and / or pressure-resistant sleeve part can be provided by the first material. At the same time, due to the use of the sliding layer made of parylene, an improved sliding behavior can be achieved.

[0013] Alternatively, the first material or the plastic material of the sleeve part can be PEEK (polyether ether ketone), PK (polyketone), PBT (polybutylene terephthalate), PEI (polyetherimide), PPA (polyphthalamide), PA (polyamide) or PPS (polyphenylene sulfide).

[0014] A ball-and-socket joint having a bearing sleeve according to the application is particularly advantageous. In particular, the ball-and-socket joint is used in a chassis assembly and / or a chassis of a vehicle. The ball-and-socket joint has a joint inner part. The joint inner part has a joint ball, wherein the joint ball is movably and / or pivotably accommodated and / or supported in an accommodation space of the bearing sleeve. A surface of the joint ball at least partially rests on the sliding layer made of parylene.

[0015] The ball-and-socket joint can be configured as a ball pin joint or as a ball socket joint. In particular, the joint inner part is a ball pin or is a ball socket. The joint inner part can have at least one joint pin, which extends away from the joint ball. In particular, the joint inner part is made of metal.

[0016] The ball-and-socket joint has various uses in vehicle construction. In particular in a chassis, the ball-and-socket joint is used to connect chassis parts, such as, for example, steering wheel members, wheel supports, steering tie rods or the like, to one another in a hinged manner or to connect the chassis parts to a steering device or to a vehicle body or to an axle support fixed to the vehicle body.

[0017] The ball-and-socket joint can have a joint housing. In particular, the joint housing is open at least on one side. Preferably, the joint housing has a housing recess. In particular, the bearing sleeve is fixed in the housing recess. In the housing recess or in the bearing sleeve, the joint ball of the joint inner part is pivotably supported relative to the joint housing. In particular, at least one joint pin of the joint inner part protrudes from an opening of the bearing sleeve and / or of the joint housing. The joint housing can be made of metal or plastic.

[0018] According to an improvement, a lubricant is arranged at least partially between the surface of the joint ball and the sliding layer made of parylene. Thereby, a hydrodynamic sliding friction and / or a mixed friction can be achieved. In particular, the lubricant is a grease or a mixture of at least two different greases.

[0019] Furthermore, a chassis assembly having a ball-and-socket joint according to the application is advantageous. The chassis assembly has in particular a first chassis part. The chassis assembly can have a second chassis part. The chassis part or the first chassis part can have or form a joint housing. Here, the bearing sleeve is fixed in the joint housing. As a result, no relative movement or at least only a limited relative movement between the joint housing and the bearing sleeve is possible. Furthermore, the joint inner part has at least one joint pin, which extends out of the bearing sleeve and the joint housing. In particular, the joint pin is fixed to the second chassis part. As a result, the two chassis parts are connected to each other in a hinged manner by means of the ball-and-socket joint. Alternatively, the joint inner part can be configured for example as a pull rod.

[0020] Finally, a method for producing a bearing sleeve according to the application is advantageous, wherein a sliding layer made of parylene is applied to the inner side of the sleeve shell part by means of chemical vapor deposition. In particular, the sliding layer made of parylene is applied to the inner side of the sleeve shell part in gaseous or plasma form. This makes it possible to produce a sliding layer which is as uniform as possible and as thin as possible at the same time. In particular, the sliding layer made of parylene has a thickness of less than 30 pm, or less than 20 pm, or less than 10 pm. Preferably, the sliding layer made of parylene has a thickness of less than 5 pm, or less than 2 pm, or less than 1 pm.

[0021] In particular, the bearing sleeve produced according to the method according to the application is a bearing sleeve according to the application as described above. Preferably, the method is improved according to the design solutions set out in connection with the bearing sleeve according to the application described herein. Furthermore, the bearing sleeve described herein can be improved according to the design solutions set out in connection with the method. BRIEF DESCRIPTION OF DRAWINGS

[0022] The application is explained in more detail below with reference to the drawings. Here, identical reference signs denote identical, similar or functionally identical components or elements. Therein:

[0023] Figure 1 A side view cross-sectional view of a ball-and-socket joint according to the application having a bearing sleeve according to the application is shown. DETAILED DESCRIPTION

[0024] Figure 1 A side view cross-sectional view of a ball-and-socket joint 1 according to the application having a bearing sleeve 2 according to the application is shown. The ball-and-socket joint 1 is here configured for example as a ball-and-socket joint. The ball-and-socket joint 1 has a joint inner part 3. The joint inner part 3 has a joint ball head 4 and a joint pin 5 extending out of the joint ball head 4. In this embodiment, the joint inner part 3 is configured as a ball-and-socket joint.

[0025] The joint head 4 is movably received or supported in the receiving space 6 of the bearing sleeve 2. Here, the joint pin 5 of the joint inner part 3 extends out of the opening 7 of the bearing sleeve 3.

[0026] The ball joint 1 has a joint housing 8. In this embodiment, the joint housing 8 is configured as an axial pot. The joint housing 8 has an open opening 9 at least on one side. Here, the openings 7 and 9 are aligned with one another such that the joint pin extends out of both the opening 7 of the bearing sleeve and the opening 9 of the joint housing 8. The bearing sleeve 2 is fixed in a housing recess 10 of the joint housing 8.

[0027] The bearing sleeve 2 has a sleeve shell part 11 made of a first material. In this embodiment, the first material is a plastic material, namely POM (polyoxymethylene) plastic. Thus, a sufficiently strong and pressure-resistant sleeve shell part 11 can be provided by the first material.

[0028] The sleeve shell part 11 determines the shape of the bearing sleeve 2. The sleeve shell part 11 forms a spherical segment-shaped receiving space 6. Furthermore, the sleeve shell part 11 has an inner side 12. The inner side 12 is at least partially spherical or configured as a hollow spherical segment in order to form the spherical segment-shaped receiving space 6.

[0029] The inner side 12 of the sleeve shell part 11 has a coating made of a second material for forming a sliding layer 13. The second material is parylene.

[0030] Due to the formation of the sliding layer 12 made of parylene, the sliding properties of the bearing sleeve 2 are improved. Thereby, the friction between the bearing sleeve 2 and the joint head 4 is reduced. Here, a particularly thin sliding layer 13 can be produced using parylene.

[0031] In this embodiment, the thickness of the sliding layer 13 made of parylene is less than 10 μιη. The sliding layer 13 made of parylene is applied to the inner side 12 of the sleeve shell part 11 by chemical vapor deposition.

[0032] Furthermore (not shown in detail here), at least partially between the surface of the joint head 4 and the sliding layer 13 made of parylene, a lubricant is arranged, whereby a hydrodynamic sliding friction and / or a mixed friction can be achieved.

[0033] List of reference signs:

[0034] 1 ball joint

[0035] 2 bearing sleeve

[0036] 3 joint inner part

[0037] 4 joint head

[0038] 5 joint pin

[0039] 6 accommodation space

[0040] 7 opening (of the bearing sleeve)

[0041] 8 joint housing

[0042] 9 opening (of the joint housing)

[0043] 10 housing recess

[0044] 11 sleeve housing component

[0045] 12 inner side surface

[0046] 13 sliding layer

Claims

1. A bearing sleeve for a ball and socket joint (1), comprising a shell part (11) made of a first material, wherein: The shell component (11) forms a spherical truncated accommodating space (6) for supporting a joint ball head (4) in an articulated manner, and the inner side (12) of the shell component (11) has a coating made of a second material to form a sliding layer (13), characterized in that the second material is polyparaxylene.

2. The support sleeve according to claim 1, characterized in that The thickness of the sliding layer (13) made of polyparaxylene is less than 30 μm, or less than 20 μm, or less than 10 μm.

3. The support sleeve according to claim 1 or 2, characterized in that The thickness of the sliding layer (13) made of polyparaxylene is less than 5 μm, or less than 2 μm, or less than 1 μm.

4. The support sleeve according to any one of the preceding claims, characterized in that The second material, parylene, contains fluorine, and in particular, at least one hydrogen atom or multiple hydrogen atoms in each parylene molecule are replaced by fluorine atoms.

5. The support sleeve according to any one of the preceding claims, characterized in that The sliding layer (13) made of parylene is applied to the inner side (12) of the housing part (11) by chemical vapor deposition and / or the housing part (11) is completely coated with the second material parylene.

6. The support sleeve according to any one of the preceding claims, characterized in that The first material forming the housing part (11) is a plastic material, in particular the first material is a thermoplastic plastic, preferably a POM (polyoxymethylene) plastic.

7. A ball and socket joint comprising a bearing sleeve (2) according to any one of the preceding claims and a joint inner part (3) with a joint ball (4), wherein: The joint ball (4) is accommodated in an articulated manner in a receiving space (6) of the bearing sleeve (2), and the surface of the joint ball (4) at least partially rests on a sliding layer (13) made of polyparaxylene.

8. The ball and socket joint according to claim 7, wherein: A lubricant is at least partially provided between the surface of the joint ball (4) and the sliding layer (13) made of polyparaxylene, thereby generating hydrodynamic sliding friction and / or mixed friction between the joint ball (4) and the bearing sleeve (2).

9. Chassis assembly comprising a ball joint (1) according to any one of claims 7 or 8, wherein The chassis component has or forms a joint housing (8), the bearing sleeve (2) is fixed in the joint housing (8), and the joint inner part (3) has at least one joint pin (5) which extends from the bearing sleeve (2) and the joint housing (8).

10. Method for producing a bearing sleeve (2) according to any one of claims 1 to 6, wherein: A sliding layer (13) made of parylene is applied to the inner side (12) of the housing part (11) by chemical vapor deposition.

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