BEARING STRUCTURE COMPONENT

Abstract

A bearing structure component for a vehicle bearing, having at least one through-opening for receiving a connecting element or a bearing which is made of foamed synthetic material, and the foamed synthetic material forms an integral foam structure. In an embodiment, at least one first local section of the integral foam structure has a wall thickness of greater than 4 mm.

Claims

1.-15. (canceled)

16. A bearing structural component for a bearing of a vehicle, comprising: at least one through-opening for receiving a connecting element or a bearing, which comprises foamed plastic, and the foamed plastic forms an integral foam structure, wherein a first local portion of the integral foam structure has a wall thickness of greater than 4 mm.

17. The bearing structural component as claimed in claim 16, wherein the first local portion has a wall thickness of greater than 10 mm.

18. The bearing structural component as claimed in claim 16, wherein the first local portion has a wall thickness of greater than 20 mm.

19. The bearing structural component as claimed in claim 16, wherein the integral foam structure has a first layer having a first porosity and a second layer having a second porosity, wherein the second layer is surrounded by the first layer, and wherein the first porosity is less than or equal to 10% and/or the second porosity is greater than 10%.

20. The bearing structural component as claimed in claim 19, wherein the second porosity is greater than 20%.

21. The bearing structural component as claimed in claim 16, wherein the integral foam structure has a second local portion which can be connected to a further component by a welding method.

22. The bearing structural component as claimed in claim 21, wherein the welding method comprises laser plastic transmission welding.

23. The bearing structural component as claimed in claim 21, wherein either the second local portion has high laser transmittance and a corresponding edge portion of the further component has high laser absorptance, or the second local portion has high laser absorptance and the corresponding edge portion of the further component has high laser transmittance.

24. The bearing structural component as claimed in claim 16, wherein the connecting element or the bearing is connected to the integral foam structure in a form-fitting, force-fitting and/or materially bonded manner.

25. The bearing structural component as claimed in claim 16, wherein at least one weld line zone, the strength of which is increased due to the foamed plastic, is formed in a region of the through-opening.

26. The bearing structural component as claimed in claim 16, wherein the foamed plastic comprises a thermoplastic material.

27. The bearing structural component as claimed in claim 26, wherein the thermoplastic material is a fiber-reinforced thermoplastic material.

28. The bearing structural component as claimed in claim 16, wherein the integral foam structure is produced by the MuCell method.

29. The bearing structural component as claimed in claim 1, wherein the bearing structural component has a first receiving portion for receiving a first bearing element and/or a second receiving portion for receiving a second bearing element.

30. The bearing structural component as claimed in claim 29, wherein at least one of the first bearing element and the second bearing element is connected to the bearing structural component in a form-fitting, force-fitting and/or materially bonded manner.

31. The bearing structural component as claimed in claim 29, wherein at least one of the first receiving portion and the second receiving portion can be closed by a cover element and/or ring element to secure the bearing element that is received in the receiving portion.

32. The bearing structural component as claimed in claim 16, wherein the bearing structural component is part of a bearing, an assembly bearing or engine bearing support arm, a link, a coupling rod, a hinged support or a transmission suspension, or is an attachment part for a bearing, or is a part that receives a bearing.

33. The bearing structural component as claimed in claim 16, wherein the bearing structural component is part of a top mount.

34. The bearing structural component as claimed in claim 16, wherein the bearing structural component is formed without ribs.

35. A vehicle bearing including a bearing structural component as recited in claim 16.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The bearing structural component and further features and advantages are explained in more detail below with reference to exemplary embodiments that are illustrated schematically in the figures, in which:

[0042] FIG. 1 shows a cross section through a bearing structural component according to a first embodiment;

[0043] FIG. 2 shows an enlarged cross section through the integral foam structure;

[0044] FIG. 3 shows a cross section through a bearing structural component according to a second embodiment;

[0045] FIG. 4 shows a cross section through a bearing structural component according to a third embodiment;

[0046] FIG. 5 shows a cross section through a bearing structural component according to a fourth embodiment;

[0047] FIG. 6 shows a plan view of a bearing structural component according to a fifth embodiment;

[0048] FIG. 7 shows a cross section through the bearing structural component illustrated in FIG. 6 along the line VII-VII; and

[0049] FIG. 8 shows a longitudinal section through a bearing structural component according to a sixth embodiment.

DETAILED DESCRIPTION

[0050] FIG. 1 shows a bearing structural component 10 according to a first embodiment, which is in the form of a strut bearing or top mount 11. A shock absorber 12 is mounted on a vehicle structure, which is not illustrated, such as a vehicle bodyshell, for example, via the top mount 11.

[0051] The top mount 11 is produced from foamed plastic, in particular fiber-reinforced foamed plastic, by a foam injection molding method, in particular the MuCell method.

[0052] As can be seen in FIG. 2, the foamed plastic forms an integral foam structure 66 which has a first layer 68 having a first porosity and a second layer 70 having a second porosity, the second layer 70 being surrounded by the first layer 68. The first layer 68 may also be referred to as covering layer or cover layer and the second layer 70 may also be referred to as core or core layer. The first layer 68 has a thickness of greater than 1 mm, in particular greater than 2 mm, the mean first porosity being less than or equal to 10% and the mean second porosity being greater than 10%, in particular greater than 20%.

[0053] The top mount 11 comprises a main body portion 14 and two transition portions 16 protruding from the main portion 14, each of the transition portions 16 leading into a flange portion 18.

[0054] The main portion 14 has a first receiving portion 20 for receiving a first bearing element 22 and a second receiving portion 24 for receiving a second bearing element 26. The two receiving portions 20, 24 are in the form of receiving openings 28.

[0055] As can be seen in FIG. 1, the first bearing element 22 is an elastomer bearing 30 which is inserted, in particular pressed, in the first receiving portion 20 or the receiving opening 28 and which mounts the shock absorber 12 elastically on the vehicle structure.

[0056] The elastomer bearing 30 has an elastomer body 32 and a metal disk 34. A damper rod 36 of the shock absorber 12 is fastened to the metal disk 34. For this, the free end of the damper rod 36 is guided through an opening 38 made in the metal disk 34 and is connected to the metal disk 34 by a fastening element 40. In the present case, the fastening element 40 is in the form of a nut, which can be screwed onto a thread of the damper rod 36.

[0057] As can also be seen in FIG. 1, the elastomer bearing 30 is held in the first receiving portion 20 by a cover element 42. For this, the cover element 42 is inserted in the receiving opening 28 of the first receiving portion 20 in such a way that it comes to bear against a circumferential projection 29 of the first receiving portion 20. In order to fasten the cover element 42 to the bearing structural component 10, the cover element 42 is welded to a second local portion 52 of the bearing structural component 10. In the present case, the second local portion 52 is in the form of a thin-walled edge portion 44 having a wall thickness between approx. 1 mm and approx. 6 mm. The cover element 42 is preferably welded to the edge portion 44 by laser plastic transmission welding. This requires that either the cover element 42 or the edge portion 44 is made of plastic and has high laser transmittance, whereas the respective other partner to be welded, that is to say the edge portion 44 or the cover element 42, has high laser absorptance.

[0058] As can be seen in FIG. 1, an additional spring 46, through which the damper rod 36 extends, is inserted in the receiving opening 28 of the second receiving portion 24. The additional spring 46 may be produced from a PU foam.

[0059] Each of the flange portions 18 has a through-opening 47 in which a respective connecting element 48 is inserted. The bearing structural component 10 may be screwed to a vehicle structure, which is not illustrated, via the connecting elements 48. The connecting elements 48 are in the form of sleeves 49 with a collar 51, which is arranged at the end and is made of metal, for screwed connections, in order to discharge the reaction forces to the vehicle structure, which is not illustrated.

[0060] As can be seen in FIG. 1, weld line zones 88, which are produced at the confluence zone of the foamed plastic, are formed in the region of the through-openings 47. The weld line zones 88 are produced behind the through-openings 47 as seen from the injection point for the foamed plastic. The strength of these weld line zones 88 is enhanced by the low viscosity of the foamed plastic due to the foamed plastic containing gas, which allows a faster filling time.

[0061] During use as intended, the shock absorber 12 subjects the middle of the bearing structural component 10 primarily to tensile and compressive loading. The reaction forces are discharged to the flange portions 18 via the connecting elements 48. As a result, the entire bearing structural component 10 is subjected to flexural loading. In order to achieve the highest possible flexural stiffness, the transition portion 16 has a first local portion 50, illustrated here by the depicted circle, which gets bigger toward the center until it reaches a maximum. At maximum, the first local portion 50 has a wall thickness of greater than 10 mm, in particular greater than 20 mm. Due to the large wall thickness, the area moment of inertia, which determines the flexural stiffness, is very high, with the result that the component stiffness with respect to flexural loading of the bearing structural component 10 is very high.

[0062] Since the first layer 68 has a porosity of less than or equal to 10%, it has a high compressive and tensile strength and stiffness. The second layer 70, which in the bearing structural component 10 connects the first layers 68, which are subjected primarily to tensile and compressive loading by the flexural loading, is subjected primarily to shear forces, however. For the flexural stiffness of the bearing structural component 10, it is therefore advantageous for a given component weight to increase the thickness of the second layer 70, that is to say the core and correspondingly its porosity, until the necessary shear resistance and stiffness of the foamed plastic are optimally utilized. Due to the large wall thickness of the first local portion 50, the flexural stiffness of the bearing structural component 10 is very high, thereby resulting in increased component stiffness with respect to flexural loading.

[0063] Further exemplary embodiments for the bearing structural component 10 are described below, the same reference signs being used for identical parts and parts which have the same function.

[0064] FIG. 3 shows a second embodiment of the bearing structural component 10, which differs from the first embodiment in that the cover element 42 engages around the edge portion 44. The cover element 42 is welded to the edge portion 44 by laser plastic transmission welding, in that the edge portion 44 has high laser absorptance and a collar portion 54 of the cover element 42 has high laser transmittance. This structure makes it possible, for example, to reinforce the structural component with carbon fibers, which naturally causes it to lose its laser transparency.

[0065] Since a very high glass fiber content counteracts the transparency, this structure simplifies the weldability. The thin, preferably 4 mm thick, laser-transparent collar portion 54 is integrated in the cover element 42. The corresponding welding surface on the bearing structural component 10 may consequently be located on a thicker wall. This is advantageous for the injection molding operation of the bearing structural component 10, and also makes it possible to set a higher porosity. This is due to the fact that, in foam injection molding, injection is frequently performed at the thinnest point rather than at the thickest point. The bearing structural component 10 is then targetedly underfilled. Complete filling is achieved by the foam-induced expansion of the melt. Because the first local portion 52 is thicker in comparison to FIG. 1, it can only be filled at completion, resulting in greater flexibility with regard to the position of the injection point.

[0066] FIG. 4 shows a third embodiment of the bearing structural component 10, which differs from the other embodiments in that the cover element 42 is connected to the bearing structural component 10 by a clip connection. For this, around the inner circumference the edge portion 44 has snap-fit elements 56, which hold the cover element 42. To fix the snap-fit elements 56, a fixed ring element 56, for example a metal ring, is pushed over the snap-fit elements 56 from the outside so that they are held in position under load.

[0067] FIG. 5 shows a fourth embodiment of the bearing structural component 10, which differs from the other embodiments in that a bearing seat 60 for a plain or ball bearing 61 is provided. This fixes a spring support 62, intended for supporting a spring element 64, with a rotational degree of freedom. As a result, the spring support 62 can be rotatably supported in relation to the bearing structural component 10. The top mount shown in FIG. 4 is used, for example, in a McPherson front axle or in steered rear axles.

[0068] FIGS. 6 and 7 show a fifth embodiment of the bearing structural component 10, which is in the form of an assembly bearing housing 80 of an assembly bearing 82. Apart from the assembly bearing housing 80, the assembly bearing 82 has a bearing 84 in the form of an elastomer bearing 86 and two connecting elements 48 in the form of sleeves 49 and serves to attach a motor vehicle drive, which is not illustrated, such as an internal combustion engine or an electric motor, for example, to a vehicle bodyshell, which is not illustrated, or to a vehicle part, which is not illustrated. The assembly bearing may be an engine bearing, for example. The elastomer bearing 86 and the sleeves 49 are inserted, in particular pressed, in through-openings 47.

[0069] As can be seen in FIGS. 6 and 7, weld line zones 88, which are produced at the confluence zone of the foamed plastic, are formed in the region of the through-openings 47. The weld line zones 88 are produced behind the through-openings 47 as seen from the injection point for the foamed plastic, which is illustrated in the present case as a triangle. The strength of these weld line zones 88 is enhanced by the low viscosity of the foamed plastic due to the foamed plastic containing gas, which allows a faster filling time.

[0070] As can also be seen in FIG. 6, the bearing structural component 10 which is in the form of an assembly bearing housing 80 has a first local portion 50 with a wall thickness of greater than 10 mm, in particular greater than 20 mm. Due to the large wall thickness, the area moment of inertia, which determines the flexural stiffness, is very high, with the result that the component stiffness with respect to flexural loading of the bearing structural component 10 is very high.

[0071] FIG. 8 shows a sixth embodiment of the bearing structural component 10, which is in the form of an link housing 90 of a link 92. Apart from the link housing 90, the link 92 has two bearings 84 which are inserted, in particular pressed or embedded by ultrasound, in through-openings 47.

[0072] Both bearings 84 are designed as elastomer bushings 94 and have a core 96 and an elastomer body 98 surrounding the core. As can be seen in FIG. 8, the left-hand elastomer bushing 94 also has an outer sleeve 100 which is made of metal and surrounds the elastomer body 98.

[0073] As can also be seen in FIG. 8, weld line zones 88, which are produced behind the through-openings 47 as seen from the injection point, are formed in the region of the through-openings 47. The strength of these weld line zones 88 is increased by virtue of the improved flow behavior of the foamed plastic.

[0074] Despite bring produced by the MuCell method, the bearing structural component 10 for automotive construction has large wall thicknesses of greater than 10 mm, preferably greater than 20 mm, which local porosities of greater than 10%, preferably greater than 20%, in combination with compact covering layers of at least 2 mm with a porosity of less than 10%, which means that high flexural stiffness combined with little material usage can be achieved.