Bearing arrangement with axial bearing disc

Abstract

Bearing arrangement comprising a thrust bearing (9) with a cage (14) and rolling elements (15) received in pockets therein, and at least one thrust bearing disk (12, 16) which has a first disk side forming a rolling element raceway and an opposing second disk side (18, 19) to be supported on a component (10), wherein one or more local recesses (24) are provided on the first disk side, which are provided as projections (20) extending from the second disk side (18, 19), and a component (10) with a support surface on which the thrust bearing disk (12, 16) is supported with the second disk side (18, 19), wherein the support surface has at least one centering recess (21, 22) into which the projection(s) (20) of the second disk side (18, 19) engage.

Description

[0001] The invention relates to a bearing arrangement with an axial bearing disk, comprising a first disk side forming a rolling element raceway and a second disk side opposite, which is to be supported on a component.

[0002] Such an axial bearing disc serves to support an axial bearing on a component, whereby two components that can rotate relative to each other are axially supported and rotated relative to each other via an axial bearing. Such axial bearings are used in a wide variety of applications. A lead screw drive is mentioned only as an example, comprising a lead screw and a screw housing, which are coupled to each other via drive elements, usually balls, that run in the threads. Either the lead screw is axially fixed and the housing is displaced along the lead screw, or the housing is axially fixed and the lead screw is displaced axially relative to the housing. In these arrangements, one component rotates while the other is rotationally fixed.Since axial forces must also be supported by the respective arrangements, a thrust bearing is interposed, which can be a ball bearing, roller bearing, or needle bearing. It typically includes a cage in which the rolling elements are arranged. In most cases, one or two thrust bearing discs are also provided on either side of the rolling element ring. Each of these discs has a rolling element raceway on one side, on which the rolling elements run. The opposite, second side of each thrust bearing disc is supported against the adjacent component.Such an arrangement is known, for example, from JP 2007- 40 498 A, in which the rolling element ring is supported on one side by a first angle disk and on the other side by a double disk pack consisting of a thinner angle disk and a thicker flat disk, which rests against the component and to which the angle disk, which extends through the thicker disk with a cylindrical flange, is fixed via bent sections.

[0003] Such an axial bearing disc requires orientation at its inner or outer diameter and must therefore be radially fixed or centered accordingly. This is possible in many applications if, for example, the respective component has a corresponding cylindrical shoulder that serves for radial orientation or centering, or something similar. Often, depending on the design of the first and second components, axial bearing discs with different diameters must be provided on both sides of the rolling element ring. In some applications, however, the first and / or second component, due to design or space constraints, does not offer the possibility of forming geometries that would serve radial guidance and thus centering, so that corresponding centering is not possible on these components.An example of this is a threaded drive, for instance a ball screw drive, in which the sleeve-like housing forms the first component and is driven rotationally, but is axially fixed and is supported by an axial bearing on an outer housing of the threaded drive or another structure. Alternatively, the threaded spindle can also be axially fixed but driven rotationally, in which case the threaded spindle forms the first component, which must be supported axially against a second, also axially fixed component such as a housing or similar. A bearing arrangement according to the preamble of claim 1 is disclosed in US 2006 / 0102438 A1. Further prior art is disclosed in JP 2009-103239A, JP 2000-337365A, JP 2010-164078A, and JP 2007-192251A.

[0004] The invention is based on the problem of providing an axial bearing disc that allows centering or orientation even in such cases.

[0005] To solve this problem, in a bearing arrangement with an axial bearing disc of the type mentioned above, it is provided according to the invention that one or more local recesses are provided on the first side of the disc, which are designed as projections extending from the second side of the disc.

[0006] The axial bearing disc according to the invention is characterized by the fact that, with respect to both sides of the disc, it is not flat but specifically profiled, meaning that an axial profile structure is created which, in turn, is able to interact with a corresponding structure on the respective component and allow radial centering. According to the invention, one or more recesses are provided on the first side of the disc, i.e., the raceway side, i.e., pressed or stamped in, which extend through to the other side, i.e., the second side of the disc, which also rests against the component in the assembly position, so that corresponding projections are formed on the second side of the disc, rising axially from the disc surface. These projections form a centering structure that enables radial centering on the respective component, be it, for example, the spindle housing or, in the case of a spindle drive, the threaded spindle.For this purpose, it is only necessary to provide the component with a corresponding centering structure on its axial end face, into which the centering structure of the axial bearing disk engages, i.e., into which the projection(s) engage. This means that, according to the invention, an axial engagement is achieved via the axially projecting centering structure on the disk side of the axial bearing disk and a corresponding axial centering structure on the component, which simultaneously allows for radial guidance and centering. The projection(s), viewed radially, are formed in the surface of the disk side; that is, they are not located directly at the inner or outer edge, but, for example, radially in the center of the disk. Similarly, the corresponding centering structure is formed on the surface of the end face of the respective component to enable large-area support of the axial bearing disk.

[0007] Several variations are conceivable regarding the geometry of the recesses and, in particular, the projections. According to a first, preferred, and especially practical variant, each recess or projection can have a round cross-section, meaning that cone-shaped, round projections rise from the disk surface. However, it is also conceivable to design the recess and the corresponding projection as an elongated shape, lying on a radius, i.e., as a rib extending, for example, by an angular increment of a few degrees, following the reference radius.

[0008] If several recesses and protrusions are provided, these are preferably all located on the same radius, which of course simplifies assembly, since the centering structure formed on the component is naturally also designed accordingly.

[0009] If several recesses and projections are provided, they are preferably arranged equidistantly in the circumferential direction, i.e., all spaced apart from each other by the same angular increment.

[0010] The bearing arrangement according to the invention comprises an axial bearing with a cage and rolling elements received therein in pockets, as well as at least one axial bearing disk of the type described above, and a component with a support surface on which the axial bearing disk is supported with the second disk side, wherein the support surface has at least one centering recess in which the projection(s) of the second disk side engage.

[0011] The bearing arrangement thus comprises the axial bearing with its axial bearing disk and the component, wherein the axial bearing disk has the disk-side centering structure in the form of the projection(s), while the component has the component-side centering structure on an axial support surface in the form of at least one centering recess. The axial bearing can be any type of bearing, i.e., a ball bearing with corresponding balls, a roller bearing with rollers, or a needle bearing with needles, although this list is not exhaustive. The first component can be any type of component, depending on the type of device in which the bearing arrangement is integrated. A threaded drive is mentioned again only as an example.

[0012] The bearing arrangement can be designed such that only one axial bearing disk is provided, on which the axial bearing or the rolling elements guided in the cage roll, while on the other component, they roll on a raceway integrally formed therein. However, it is also conceivable that the bearing arrangement has a second axial bearing disk of the type described above, wherein a second component with a support surface is provided, against which the second axial bearing disk is supported with its second side. The support surface has at least one centering recess into which the projection(s) of the second disk side engage. In this embodiment of the bearing arrangement, the rolling elements are thus supported on both sides by an axial bearing disk according to the invention, meaning that both the first and the second component have corresponding centering structures in the form of the centering recesses.This design is used when neither component can have corresponding radial centering geometries such as a shoulder or similar, which would allow a simple, flat axial bearing disc to be provided for support on this side.

[0013] The geometry of the centering device can vary. According to one alternative, only one centering recess in the form of a circumferential annular groove can be provided. All the projections of the axial bearing disk engage in this single annular groove, thus achieving centering. This design allows for particularly simple assembly, as the axial bearing disk can be positioned in any desired rotational position with the centering projections engaging. Alternatively, it is conceivable that several recesses are provided, with either multiple projections engaging in each recess, or the number of recesses corresponding to the number of projections. Such a recess, which can accommodate multiple projections, can be designed as an elongated slot that is slightly curved, follows a radius, and extends by an angular increment. It is also conceivable to dimension such an elongated slot so that only one projection engages in it.Such a slotted design also allows for a certain degree of assembly freedom, meaning a certain tolerance regarding the rotational alignment of the axial bearing disk relative to the component's end face is possible during positioning. Alternatively, instead of a slotted design, each recess can also be a bore, with the number of bores corresponding to the number of projections. In this case, a projection engages in each bore, and the axial bearing disk must be aligned accordingly in its rotational position to insert the projections into the recesses.

[0014] Furthermore, the invention relates to a threaded drive comprising a threaded spindle and a spindle housing coupled via drive elements, wherein either the threaded spindle is displaceable relative to the axially fixed spindle housing, or wherein the spindle housing is displaceable relative to the axially fixed threaded spindle, as well as a bearing arrangement of the type described above, wherein the fixed spindle housing or the fixed threaded spindle forms the first component, which is supported on the second component via the axial bearing comprising one or two axial bearing discs. Such a threaded drive is a specific implementation of the general bearing arrangement described above, or rather, incorporates such a bearing arrangement as a specific operating unit.The fixed component, i.e., either the spindle housing or the threaded spindle, is supported on the second component, i.e., for example, a housing of the spindle drive or a housing of an actuator of which the spindle drive is a part, via the axial bearing comprising the cage with the rolling elements and one or two axial bearing discs according to the invention. The threaded drive can be any type of threaded drive, preferably a ball screw drive.

[0015] Such a threaded drive according to the invention can be part of an electromechanical actuator, i.e., an actuating device by which a rotational movement is converted into a linear translational movement. It is therefore an actuator comprising a rotation-translation converter, wherein the actuator has or is associated with an electric motor by which the axially fixed, but rotatable, first component, i.e., either the spindle housing or the threaded spindle, is driven in rotation, while the linearly movable component, i.e., the displaceable threaded spindle or the displaceable spindle housing, is responsible for the linear actuating movement, which is then transmitted to an element to be actuated.Such an actuator can be part of a braking device according to the invention, comprising a brake caliper with two brake pads and the electromechanical actuator comprising such a threaded drive, wherein an axial force is applied to one of the brake pads via the actuator in order to move the two brake pads in contact with a brake disc located between them.

[0016] The invention is explained below with reference to exemplary embodiments and the drawings. The drawings are schematic representations and show: Fig. 1 a perspective view of part of a bearing arrangement according to the invention in the form of a threaded drive, Fig. 2. A schematic representation in the form of a longitudinal sectional view of such a bearing arrangement in the form of a threaded drive, Fig. 3 a perspective view of an axial bearing comprising two axial bearing discs according to the invention, Fig. 4 An enlarged partial view of the connection area of ​​an axial bearing disk according to the invention with a component of the bearing arrangement, here a spindle housing, Fig. 5 a perspective view of a spindle housing of the screw drive Fig. 2 of a first embodiment, Fig. 6 a perspective view of a spindle housing of the screw drive Fig. 2 of a second embodiment, Fig. 7 a perspective view of a spindle housing of the screw drive Fig. 2 of a third embodiment, and Fig. 8 a schematic representation of a braking device comprising a threaded drive according to the invention.

[0017] Fig. Figure 1 shows a partial view of a bearing arrangement 1 according to the invention, here in the form of a respective part of a threaded drive 2 according to the invention (see Figure 1). Fig. 2) The bearing arrangement 1, or the screw drive 2, for example a ball screw drive, comprises a first component 3, here in the form of a sleeve-like spindle housing 4, which has a central bore with an internal thread 5 through which a threaded spindle 7, shown here only stylized, engages and has an external thread 6. Rolling elements in the form of balls (not shown in detail) are arranged between the internal and external threads 6, 7, as is usual in such screw drives 2. In the example shown, the spindle housing 4 is provided with a toothed section 8, which is coupled to a rotary drive comprising an electric motor and, optionally, a gearbox, so that the spindle housing 4 can be driven in a rotary direction. The spindle housing 4 is fixed in position, while the threaded spindle 7 can be pushed axially through the spindle housing 4 in one direction or the other, depending on the direction of rotation.

[0018] To support the spindle housing 4 in an axially fixed position so that axial forces can be transmitted, an axial bearing 9 is provided, via which the spindle housing 4 is axially supported on a second component 10, here for example a housing 11 of the spindle drive or actuator housing or similar.

[0019] The axial bearing 9 consists of a first axial bearing disk 12, which rests against an axial end face 13 of the spindle housing 4. The axial bearing 9 further comprises a cage 14 with rolling elements 15 arranged in two rows therein, and a second axial bearing disk 16, which rests against the second component 10. The two axial bearing disks 12 and 16 are simple, flat, i.e., non-angled, bearing disks, which are to be centered accordingly on the end face 13 of the spindle housing 4 and on the end face 17 of the second component 10. For this purpose, see [reference to be added]. Fig. 3, each axial bearing disk 12, 16 has several axially projecting projections 20 on the respective disk side 18, 19 facing the end face 13 or 17, which in the example shown according to Fig. 3 are designed as simple pins with a round cross-section. They are created by introducing corresponding recesses on the opposite side of the disc. Fig. Figure 3 shows the axial bearing 9 in a perspective view, with the axial bearing disc 12 shown in detail with the projecting projections 20. The axial bearing disc 16 located on the opposite side is identically designed and arranged in a mirror image.

[0020] The projections 20 are located within the surface of the disk side 12, 19, and are therefore neither at the inner nor the outer edge, but in the example shown are arranged approximately in the center. They are equidistant from one another in the circumferential direction. Instead of the shown, cross-sectionally round projections (with corresponding round depressions on the other disk side), the projections 20 can also be designed as elongated projections following the radius. Preferably, regardless of the geometry, all projections 20 lie on the same radius.

[0021] The projections 20 allow for the centering of the respective axial bearing disk 12, 16 on the respective first or second component 3, 10. For this purpose, a centering recess 21, 22 is provided on the respective end face 13, 17 of each of the components 3, 10, i.e., the spindle housing 4 and the housing 11 respectively. These recesses can have different geometries, as will be discussed below. Just as the projections 20 extend axially, the recesses 21, 22 are also axially integrated into the respective end face 13, 17. In the assembly position, when the axial bearing disks 12, 16 are in place, the projections 20 engage in the respective centering recesses 21, 22, thus ensuring centering and radial fixation. Fig. As 2 clearly shows, none of the components 3, 10 have any centering shoulders or other provisions for radial centering; centering is achieved solely via the centering projections 20 and the centering recesses 21, 22.

[0022] An enlarged partial view of the connection area of ​​the axial bearing disc 12 with the spindle housing 4 is shown in Fig. Figure 4 shows that the axial bearing disc 12 rests with its disc side 23 in a flat contact with the end face 13. The projections engage in at least one centering recess 21, as shown. Fig. 4 clearly shows. In Fig. Figure 4 also shows the recess 24 on the disc side 23, which extends as a projection 20 to the disc side 18. The engagement configuration on the second component 10 is shown in the same way on the side of the axial bearing disc 16.

[0023] The Fig. Figures 5-7 show different variants of the centering recess 21, the same statements also apply to the design of the centering recess 22.

[0024] Fig. Figure 5 shows the spindle housing 4, where the centering recess 21 is designed in the form of a circumferential annular groove 25, which is slightly wider in diameter than the projections 20, so that they engage in the annular groove 25 with very little play. In this version, the axial bearing disc 12 can be mounted in any rotational position.

[0025] In the design according to Fig. 6 Several centering recesses 21 are provided, which are designed in the form of elongated holes 26 following the radius. They require a certain orientation of the axial bearing disc 12 such that the projections 20 can engage in the elongated holes 26; however, a certain amount of rotational play is allowed.

[0026] In the design according to Fig. Finally, the centering recesses 21 are designed as simple bores 27, the diameter of which is slightly larger than the diameter of the circular pins. Here, the axial bearing disc 16 can only be mounted in defined rotational positions.

[0027] As described, the one or more centering recesses 22 can be designed in the same way as an annular groove 25, as a slot 26 or as a bore 27.

[0028] Fig. Figure 8 shows a braking device 28 according to the invention in the form of a schematic diagram. The braking device 28 comprises a brake caliper 29 and two brake pads 30, 31, between which a brake disc (not shown in detail) is arranged. Furthermore, an actuator 32 is provided, by means of which the brake pad 31 can be moved axially and pressed against the brake disc. This means that a corresponding axial force can be applied to the brake pad 31 via the actuator 32.

[0029] The actuator 32 comprises an electric motor 33 with a downstream gearbox 34. The gearbox 34 is in turn connected to the threaded spindle drive 2 according to the invention, which represents a rotation-translation converter. The rotational movement of the electric motor 33, or the output of the gearbox 34, is converted into a translational movement for the linear displacement of the brake pad 31. For this purpose, the threaded spindle drive 2 has a threaded spindle 7 with an external thread 6, which is coupled to the gearbox 34 via its spindle shaft 35. Furthermore, the spindle housing 4 is provided. It is linearly displaceable but rotationally secured within a housing 36 of the threaded spindle drive 2, or the actuator 32. Here, the spindle housing 4 functions as a linearly movable piston and accommodates the threaded spindle 7. In the example shown, the spindle housing 4 has a threaded component 37 with an internal thread.The threaded spindle 7 and the spindle housing 4 are coupled to each other via drive elements 38 in the form of balls, as is usual in a threaded spindle drive 2. A rotation of the axially fixed threaded spindle 7 therefore inevitably leads to a linear displacement of the spindle housing 4, which in turn is connected to the brake pad 31.

[0030] For axial support and rotational mounting of the threaded spindle 7, an axial bearing 9 according to the invention is provided with the axial bearing disk(s) 12, 16, which is arranged between the threaded spindle 7 or a collar 39 of the threaded spindle 7 and a flange of the housing 36. The axial forces acting on the spindle drive 2 when the brake pad 31 is pressed against it are supported towards the housing 36 by the axial bearing 9 with its correspondingly high load-bearing capacity but low friction, while simultaneously rotating the spindle 7 relative to the housing 36.

[0031] In this example, the threaded spindle 7 is the axially position-fixed, rotary-driven component, while the spindle housing 4 is linearly displaced but does not rotate, unlike the preceding examples where the spindle housing is axially position-fixed and rotary-driven, while the threaded spindle 7 is axially displaced. Reference symbol list 1 Storage arrangement 2 screw drive 3 threaded sleeve 4 spindle housings 5 internal threads 6 external threads 7 threaded spindle 8 gear teeth 9 axial bearings 10 components 11 cases 12 Axial bearing disc 13 Front surface 14 Cage 15 rolling elements 16 Axial bearing disc 17 Front surface 18 disc side 19 disc side 20 advantages 21 Centering recess 22 Centering recess 23 disc side 24 In-depth study 25 Ring groove 26 elongated holes 27 bore 28 Brake system 29 Brake caliper 30 brake pads 31 brake pads 32 Actuator 33 Electric motor 34 gearboxes 35 Spindle shaft 36 cases 37 Threaded component 38 drive elements 39 Federal

Claims

[1] Bearing arrangement comprising a thrust bearing (9) with a cage (14) and rolling elements (15) received in pockets therein, and at least one thrust bearing disk (12, 16) which has a first disk side forming a rolling element raceway and an opposing second disk side (18, 19) which is supported on a component (10), wherein one or more local recesses (24) are provided on the first disk side, which are provided as projections (20) extending from the second disk side (18, 19), and a component (10) with a support surface on which the thrust bearing disk (12, 16) is supported with the second disk side (18, 19), wherein the support surface has at least one centering recess (21, 22) into which the projection(s) (20) of the second disk side (18, 19) engage. [2] Storage arrangement according to claim 1, characterized by, that the or each depression (24) and projections (20) of the axial bearing disk are round in cross-section or, lying on a radius, elongated. [3] Storage arrangement according to claim 1 or 2, characterized by , that the multiple depressions (24) and projections (20) lie on the same radius. [4] Storage arrangement according to claim 3, characterized by , that the multiple depressions (24) and projections (20) are arranged equidistantly in the circumferential direction. [5] Storage arrangement according to one of the preceding claims, characterized by , that a second axial bearing disk (12, 16) is provided, wherein a second component with a support surface is provided, on which the second axial bearing disk (12, 16) is supported with the second disk side (18, 19), wherein the support surface has at least one centering recess (21, 22) into which the projection(s) (20) of the second disk side (18, 19) engage. [6] Storage arrangement according to one of the preceding claims, characterized by , that only one centering recess (21, 22) in the form of a circumferential annular groove (25) is provided, or that several centering recesses (21, 22) are provided, wherein either several projections (20) engage in each centering recess (21, 22), or wherein the number of centering recesses (21, 22) corresponds to the number of projections (20). [7] Storage arrangement according to claim 6 , characterized by , that each centering recess (21, 22) is designed as an elongated hole (26) or as a bore (27). [8] A screw drive comprising a threaded spindle (7) and a spindle housing (4) coupled via drive elements (38), wherein either the threaded spindle (7) is displaceable relative to the axially fixed spindle housing (4), or wherein the spindle housing (4) is displaceable relative to the axially fixed threaded spindle (7), and a bearing arrangement (1) according to one of claims 1 to 7, wherein the fixed spindle housing (4) or the fixed threaded spindle (7) forms the first component, which is supported on the second component via the axial bearing (9) comprising an axial bearing disk (12, 16) or two axial bearing disks (12, 16). [9] Brake device comprising a brake caliper (29) with two brake pads (30, 31) and an electromechanical actuator (32) comprising a threaded drive (2) according to claim 8 for applying an axial force to a brake pad (31).

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