Roller bearing and hydrostatic axial piston machine in swashplate design with one roller bearing

Abstract

Roller bearings with two concentric circular arc-shaped roller tracks (20, 22), wherein several rolling elements (24) are accommodated between the two roller tracks (20, 22), and wherein the outer roller track (22) is formed on an outer bearing shell (26; 126; 226; 326; 626), and wherein a contact area (28; 128; 228; 328; 528; 628) is formed on the outer circumference of the outer bearing shell (26; 126; 226; 326; 626), which has the form of a section of the shell of a circular cylinder, wherein adjacent to the contact area (28; 128; 228; 328; 528; 628) a reduced area (30; 130; 230; 330; 530; 630) is formed, which The bearing area (28; 128; 228; 328; 528; 628) is inclined and / or formed by a reduced diameter compared to the bearing area (28; 128; 228; 328; 528; 628) and / or by material removal, characterized in that the circular arc bearing shell (126; 226; 326) has end sections (134; 234;334) has, over whose respective entire width the mounting area (128; 228; 328) is formed, and wherein the reduced area (130; 230; 330) extends over a central area of ​​the bearing shell (126; 226; 326) arranged between the end sections (134; 234; 334).

Description

[0001] The invention relates to a roller bearing according to the preamble of claim 1 and an axial piston machine in swashplate design with such a roller bearing.

[0002] In axial piston machines with adjustable stroke volume, it is known to design a swashplate as a pivoting cradle, which can be pivoted against a housing via an adjustment device. By adjusting the pivot angle of the pivoting cradle relative to a cylinder drum rotating about an axis, the stroke of the pistons coupled to the swashplate is adjusted during their rotation about an axis of the axial piston machine.

[0003] Since adjusting the swivel angle results in a relative movement of the swivel cradle to the housing of the axial piston machine, bearings are known to be used for the support of the swivel cradle on both sides of the axis, which are designed as pairs of arcuate tracks, one of which has a larger diameter and is located on the housing, while the other has a smaller diameter and is located on the swivel cradle.

[0004] During the operation of such axial piston machines, the working pressure acting on the pistons results in a respective support force from the pistons onto the swashplate, which can lead to deflection in the area of ​​the swashplate between the two bearings, approximately along the axis. This results in a detrimental change in the relative positions of the circular arcs of each bearing, as the swashplate-side track tilts and becomes inclined relative to the housing-side track.

[0005] In German patent applications DE 197 27 071 A 1 and DE 10 2008 013 010 A1, the two bearing surfaces of each bearing form a plain bearing. DE 197 27 071 A 1 discloses a hydrostatic relief system in the two plain bearings, optimized with regard to the deflection of the pivot bearing. DE 10 2008 013 010 A1 shows compliant areas to compensate for the deflection of the pivot bearing. It is proposed that the area of ​​the housing against which a stationary bearing shell rests, or the area of ​​the pivot bearing that rests against the bearing shell and slides against it, be made compliant. Alternatively, it is proposed that the bearing shell itself be made compliant.

[0006] German patent application DE 10 2012 214 343 A1 discloses a bearing arrangement for a pivoting cradle of an axial piston machine, wherein each of the two bearings has a pair of circular arc-shaped roller tracks between which rolling elements are clamped. The pivoting cradle is thus supported in the housing by two roller bearings. The rolling elements are barrel-shaped, so that any deflection of the pivoting cradle, and thus any tilting or misalignment of the pivoting cradle-side roller track, can be compensated for by the shape of the rolling elements, as the contact points of the pivoting cradle-side roller track on the rolling elements change.

[0007] A disadvantage of such axial piston machines is that the barrel-shaped rolling elements always have a reduced contact width, i.e., a shortened line of contact. During operation of the axial piston machine with the deflection of the swashplate that must be tolerated, the contact areas on both the pivoting cradle and housing sides migrate towards the inner edge of the rolling elements. This adversely affects the load-bearing capacity of the rolling elements.

[0008] A radial groove ball bearing for a pulley is known from US Patent 2007 / 0 232 428 A1. This bearing has a recess on the otherwise circular cylindrical outer circumferential surface of the outer ring, which forms an inclined surface. With spherical rolling elements, only a point load distribution on the rolling elements can be achieved from the outset, unlike with the roller-shaped rolling elements according to the invention.

[0009] WO 2014 / 058 038 A1 discloses a tapered roller bearing which has a multitude of recesses on the inner circumferential surface of the inner ring. The recesses are so small that they have essentially no effect on the linear load distribution on the tapered rollers.

[0010] US Patent 5,286,117 A discloses a tapered roller bearing in which the outer circumferential surface of the outer ring is slightly conical in order to influence the linear load distribution on the tapered rollers.

[0011] From DE 100 81 556 B4, an axial piston machine is known whose pivoting cradle is pivotally mounted by means of circular cylindrical rolling elements. The problem of load distribution on the rolling elements is not addressed.

[0012] In contrast, the invention is based on the objective of creating a roller bearing in which tilting or misalignment of one of the roller tracks can be tolerated without restricting the roller bearing to barrel-shaped or convex rolling elements with a correspondingly reduced contact width. Furthermore, the invention is based on the objective of creating an axial piston machine in a swashplate design in which the two roller bearings of the pivoting cradle can tolerate deflection of the pivoting cradle without restricting the roller bearings to barrel-shaped or convex rolling elements with a small contact width. The roller bearing according to the invention particularly takes into account the fact that the pivoting cradle of an axial piston machine performs a finite pivoting movement, whereby the roller bearing is loaded in a predetermined directional range, which is defined by the orientation of the pistons and the possible positions of the pivoting cradle.

[0013] This problem is solved by a roller bearing with the features of claim 1 and by an axial piston machine in swashplate design with the features of claim 16.

[0014] The claimed roller bearing or rolling bearing has two concentric circular arc-shaped roller tracks, in which several rolling elements are accommodated. The inner roller track can be formed on an inner (e.g., movable) bearing shell or on an inner (e.g., movable) component. The outer roller track is formed on an outer (e.g., stationary) bearing shell, on the outer circumference of which a contact area in the form of a circular cylinder segment for an outer (e.g., stationary) component is formed. According to the invention, a reduced area is formed adjacent to the contact area, which is angled towards the contact area and / or formed by a diameter reduced compared to the contact area and / or by a reduction in material.This creates a gap between the reduced area and the outer component, thus forming a roller bearing in which tilting or misalignment of the inner roller races can be tolerated without restricting the roller bearing to barrel-shaped or crowned rolling elements, since the rolling elements and the outer bearing shell can follow the tilting or misalignment, at least in sections. In this way, the two roller races and the rolling elements remain in approximately the same relative position to each other, while the relative position of the outer bearing shell to the outer component changes, at least in sections, according to the tilting or misalignment.

[0015] In a particularly preferred embodiment, the outer bearing shell is flexible. More precisely, the bearing shell is designed such that the reduced area relative to the contact area is elastically movable outwards and thus towards the outer component. It is further preferred that, during the elastic deformation of the reduced area, the contact area always remains in contact with the outer component.

[0016] In one embodiment of the invention, the attachment area is a first attachment area, while the reduced area is a second attachment area which is inclined to the first attachment area.

[0017] If the tilting or inclination of the inner component in two directions or with alternating signs is to be tolerated, a third contact area for the outer component is formed adjacent to the first contact area, angled relative to both the first and second contact areas. The first contact area represents a central contact area, while the second and third contact areas each represent lateral contact areas.

[0018] The installation areas are preferably curved surfaces.

[0019] In connection with the first embodiments, the helix angle of a contact area is defined in this document as the angle of inclination of the affected contact area that can result from material removal from the outer surface of the bearing shell. The helix angle of the inner raceway is defined in this document as the angle of tilt or inclination of the inner raceway that results from the deflection of the inner component and that can vary.

[0020] To achieve asymmetric optimization when the inner roller track or inner component is tilted or inclined in two directions or with a changing sign, it is preferred that the magnitude of the inclination angle of the second contact area is not equal to the magnitude of the inclination angle of the third contact area. This means that the second and third contact areas are not only inclined in different directions, but also with different steepness.

[0021] Preferably, a border is formed between the installed area and the reduced area. This defines the boundary between the two areas.

[0022] The elastic outward movement of the reduced area occurs primarily through bending of the reduced area relative to the contact area. Additionally, the edge can also yield elastically by being pressed in.

[0023] If the tilt or inclination predominantly reaches a predetermined value, the edge can simply be formed at the transition between the first and second contact areas. If the tilt or inclination usually reaches two predetermined values, edges can simply be formed at the transitions between the three contact areas. However, if intermediate values ​​of tilt or inclination also need to be optimally tolerated, the transition(s) can be rounded.

[0024] For manufacturing reasons, a second embodiment prefers to have a step or shoulder at the edge. This makes the edge position more reproducible and dimensionally accurate than in the first embodiments. More precisely, the widths of both the finished and ground contact area and the reduced area are more reproducible and dimensionally accurate than with contact areas positioned at an angle to each other.

[0025] To reduce stress, it is preferred if a rounded transition is formed between the reduced area and the edge.

[0026] The step can have a flank positioned between the rounded transition and the edge, angled between 90 and 120 degrees to the contact area and the reduced area. A flank angled at 90 degrees to both the contact area and the reduced area, and therefore radially oriented, is preferred.

[0027] For manufacturing reasons, it is preferred if the reduced area also has the shape of a section of the shell of a circular cylinder. The circular cylinder of the reduced section has a smaller diameter than the circular cylinder of the original section.

[0028] If the rolling elements are cylindrical rollers or needle rollers, the two roller tracks result in line contact over the entire length of the rolling elements, thus providing optimal force distribution over the length of the rolling elements and over the width of the bearing shell.

[0029] Alternatively, the rolling elements can also be convex or barrel-shaped, which further increases the tolerance for tilting or skewing.

[0030] In a preferred embodiment, the contact area and the reduced area have a constant width, either section by section or over the entire length of the arc-shaped bearing shell or over the entire circumference of the annular bearing shell. In the first embodiments, this results in a constant helix angle for the second contact area. The edge between the first and second contact areas is then parallel to the outer edges of the bearing shell, either section by section or over its entire length.

[0031] From a manufacturing perspective, it is simple if the reduced area extends over the entire length of the arc-shaped bearing shell or over the entire circumference of the annular bearing shell.

[0032] Manufacturing effort is minimized if the bearing shell has a uniform cross-sectional area over its entire length or circumference, i.e., if the inside of the bearing shell facing the rolling elements also has a uniform shape over its entire length or circumference.

[0033] If the support and force conditions change along a section of the length or circumference of the bearing shell, the roller bearing according to the invention can be adapted by increasing or decreasing the widths of the contact area and the reduced area along the section. In this case, the edge between the contact area and the reduced area along this section is not annular. In the case of a circular arc-shaped bearing shell, it is particularly preferred if the width of the reduced area is at its maximum in the center of the bearing shell.

[0034] According to the invention, the circular arc-shaped bearing shell has two end sections, over the entire width of which the circular cylindrical contact area is formed, i.e., no reduced area is provided. The reduced area then extends only over a central area of ​​the bearing shell located between the two end sections.

[0035] The roller bearing according to the invention can be further developed into a bearing arrangement with two such roller bearings, wherein the two inner roller tracks and the two bearing shells are arc-shaped, and wherein the respective reduced areas are formed on the mutually facing side edges of the two bearing shells.

[0036] A particularly preferred application of this bearing arrangement is in the support of the swashplate of an axial piston machine. The two inner roller tracks are formed on the swashplate, while the two bearing shells bear against a contact surface of the axial piston machine's housing. In particular, the two contact areas of the two outer bearing shells are always in contact with the housing's contact surface. This creates a swashplate axial piston machine in which the two roller bearings of the pivoting cradle can tolerate its deflection without the roller bearings being limited to barrel-shaped or crowned rolling elements with point contact.

[0037] Preferably, in the first embodiments, the inequality holds. α2>arctantanα1max×l1l2, where α2 is the angle of inclination of the second contact area relative to the contact surface of the housing. Thus, 180° - α2 is the angle between the first and the second contact area. Furthermore, α 1max The maximum skew angle of the inner roller track. Furthermore, l1 is a length of the rolling elements. Furthermore, l2 is the projection of the width of the second contact area onto the contact surface of the housing.

[0038] Several embodiments of the roller bearing according to the invention and one embodiment of the axial piston machine according to the invention are shown in the drawings. The invention will now be explained in more detail with reference to the figures in these drawings.

[0039] They show Fig. 1 in a longitudinal section an axial piston machine according to the invention in swashplate construction according to an exemplary embodiment, Fig. 2 in a perspective view a bearing arrangement with two roller bearings according to a first embodiment, Fig. 3 in a perspective view a bearing shell of the first embodiment according to Fig. 2, Fig. 4 in a schematic cross-section a bearing according to the first embodiment, Fig. 5 isolated components of the bearing in a schematic cross-section Fig. 4, Fig. 6 in one view a bearing arrangement with two roller bearings according to a second embodiment according to the invention, Fig. 7 in a perspective view a bearing arrangement with two roller bearings according to a third embodiment according to the invention, Fig. 8 in one view a bearing shell of a fourth embodiment of the roller bearing according to the invention, Fig. 9 in one view a circular ring-shaped bearing shell of a fifth embodiment of the roller bearing according to the invention, Fig. 10 in a view a circular bearing shell of a sixth embodiment of the roller bearing according to the invention, Fig. 11 in a cross-section a bearing shell according to the second embodiment of the roller bearing according to the invention in an intermediate state of its manufacture, and Fig. 12 in a cross-section the bearing shell made of Fig. 11 after their completion.

[0040] Fig. Figure 1 shows a longitudinal section of an axial piston machine according to the invention in a swashplate design. It has a cylinder drum 2 rotationally fixed to the outer circumference of a drive shaft 1, on the circumference of which several evenly distributed cylinder bores 4 are provided, of which in Fig. Figure 1 shows only one cylinder bore 4. Within the cylinder bores, respective pistons 6 are guided axially for movement and are coupled via respective piston feet 8 and sliding shoes 10 to a stationary swashplate, which is designed as a pivoting cradle 12. The pivoting cradle 12 is penetrated in its center by the drive shaft 1.

[0041] The swivel cradle 12 can be pivoted about a (not shown) pivot axis via an adjusting device 14, which is perpendicular to the drive shaft 1 and parallel to the plane of the drawing. Fig. 1. When the drive shaft 1 rotates with the cylinder drum 2 and the pistons 6, and when the pivoting cradle 12 is aligned perpendicular to the drive shaft 1, no stroke of the pistons 6 is generated in the cylinder bores 4. However, when the pivoting cradle 12 is tilted relative to the drive shaft 1 via the adjusting device 14, each piston 6 performs an inward and an outward stroke in its cylinder bore 4 during one revolution. With each change in the pivot angle, the pivoting cradle 12 moves about the pivot axis and relative to the housing 16 of the axial piston engine. For this purpose, the pivoting cradle 12 is supported and mounted on two opposite sides of the drive shaft 1 by a respective arc-shaped roller bearing 18 relative to the housing 16.

[0042] The explanations regarding Fig. 1 applies to all embodiments, since the invention in Fig. 1 is not visible.

[0043] Fig. Figure 2 shows the pivoting cradle 12 with the two roller bearings 18 without the housing 16 in a perspective view. The corresponding first embodiment is not part of the invention, although it has many features that can be used within the scope of the invention. In particular, features of the first embodiment can be used in the second to sixth embodiments, insofar as they are incorporated into the descriptions of the Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10, Fig. 11 to Fig. 12 unless otherwise stated. Each roller bearing 18 has a circular arc-shaped inner raceway on the pivot side and a circular arc-shaped outer raceway 22 on the housing side, between which a plurality of circular cylindrical rolling elements 24 are clamped. The two outer raceways 22 are formed on the inner sides of respective circular arc-shaped bearing shells 26, which are supported on the housing 16 via their outer surfaces (cf. Fig. 1).

[0044] Fig. Figure 3 shows a circular arc-shaped bearing shell 26 of the axial piston machine according to the invention. Fig. 1 or of the first embodiment of the roller bearing according to the invention Fig. 2 in a perspective view. On the outer surface of the bearing shell 26, over which the bearing shell 26 is attached to the housing 16 (cf. Fig. 1) The bearing shell 26 is supported by two parallel, strip-shaped contact areas 28, 30, wherein a first contact area 28 has a circular cylindrical shape with respect to the (not shown) pivot axis, while a second contact area 30 represents a section of a conical shell. The first contact area 28 is slightly narrower than the second contact area 30. An edge 33 between the two contact areas 28, 30 is parallel to the side edges of the bearing shell 26. On the inside of the bearing shell 26, next to the inner raceway 20, a circumferential radial projection is formed, which serves to guide the rolling elements 24.

[0045] The bearing shell 26 has a constant cross-section over its entire length, thus minimizing its manufacturing effort.

[0046] Fig. Figure 4 shows a cross-section through one of the roller bearings 18 according to the first embodiment. During operation of the axial piston machine according to the invention and under low support load, which is transferred from the swashplate 12 to the housing 16, the first contact area 28 rests against a correspondingly shaped contact surface 32 of the housing 16. However, when the pistons 6 are pressed against the swashplate 12 in the cylinder bores 4 by the working pressure and the swashplate is supported on the housing 16 via the two lateral roller bearings 18, a variable deflection of the pivot cradle 12 occurs, which leads to a variable helix angle α1 of the inner roller track 20 of the pivot cradle 12.

[0047] Fig. Figure 5 shows the roller bearing 18. Fig. 4 including a section of the pivot cradle 12, on which the inner roller track 20 is formed. In this case, Fig. Figure 5 shows the maximum deflection of the swivel cradle 12, which thus results in a maximum inclined angle α. 1max the inner roller track 20. In this operating state, the rolling elements 24 and the bearing shell 26 can also tilt and become inclined. In this case, the bearing shell 26 is no longer supported by the first contact area 28 but by the second contact area 30, which is inclined relative to it, on the (in Fig. The second contact area 30 (shown only schematically) is positioned at an angle α2 relative to an extension of the first contact area 28 or relative to the contact surface 32 (in the non-tilted state of the bearing shell 26). The relationship stated above applies. α2>arctantanα1max×l1l2, where l1 is the length of the rolling elements 24, while l2 is the length of the projection of the width of the second contact area 30 onto the extension of the first contact area 28 or (in the non-tilted state of the bearing shell 26) onto the contact surface 32 of the housing 16.

[0048] The representations of Fig. 4 and Fig. 5 and the related descriptions also apply to the following embodiments according to the Fig. 6, Fig. 7 to Fig. 8 to.

[0049] Fig. Figure 6 shows a second embodiment of a bearing arrangement according to the invention with two roller bearings for supporting the pivot cradle 12, the difference being that to the first embodiment according to Fig. As can be seen in Figure 2, no second contact area 130 is provided at the two end sections 134 of each circular arc bearing shell 126, but rather the first contact area 128 extends over the full width of each end section 134. Thus, the second angled or inclined contact area 130 extends only over a central area of ​​the bearing shell 126.

[0050] In the first embodiment according to the Fig. 2 and Fig. 3 and in the second embodiment according to Fig. 6 is in each case a symmetrical and uniform stress correction independent of the swivel angle of the swivel cradle 12 by the shape of the bearing shell 26; 126.

[0051] Fig. Figure 7 shows a third embodiment of a bearing arrangement according to the invention with two roller bearings for supporting the pivot cradle 12, wherein the first contact area 228 is provided at the end sections 234 of the circular arc-shaped bearing shells 226 over the entire width of the respective bearing shell 226. Thus, the second angled or inclined contact area 230 extends only in the central region over the bearing shell 226. In contrast to the first embodiments, the width of both the first contact area 228 and the second contact area 230 varies. More precisely, near the end sections 234, the first contact area 228 is comparatively wide, while the second contact area 230 is comparatively narrow, whereas in the middle of the respective bearing shell 226, conversely, the first contact area 228 is comparatively narrow, while the second contact area 230 is comparatively wide.In the middle of the bearing shell 226, the width of the first contact area 228 has a minimum and the width of the second contact area 230 has a maximum.

[0052] The edge 233 between the two attachment areas 228, 230 can thus (from a corresponding perspective) appear curved. Therefore, in the third embodiment according to Fig. 7 A stress correction is given which depends on the swivel angle of the swivel cradle 12. Due to the symmetrical design of the bearing shell 226, a symmetrical, i.e., uniform, progression of the stress correction is given for both signs of the swivel angle.

[0053] Fig. Figure 8 shows a circular arc-shaped bearing shell 326 according to a fourth embodiment of the roller bearing according to the invention in a side view. The contours of the first contact area 328, the edge 333, and the second contact area 330 in the central region of the bearing shell 326 are comparable to those of the third embodiment. Fig. 7. In contrast to the third embodiment, the end sections, of which in Fig. Figure 8 shows only one end section 334, over which the first plant area 328 extends. The edge 333 between the two plant areas 328, 330 has a kink in the area of ​​each end section 334.

[0054] Fig. Figure 9 shows an annular bearing shell 426 according to a fifth embodiment of the roller bearing according to the invention. The bearing shell 426 is a geometric doubling of the bearing shell 326 of the fourth embodiment according to Fig. 8. In contrast to the preceding embodiments, the roller bearing formed according to the invention is not intended for supporting a pivoting cradle 12. Rather, it supports an inner component (not shown in detail) rotating about an axis of rotation 435. The bearing shell 426 can adapt to two opposite deflection directions of the inner component by means of the two inclined second contact areas 230 arranged on opposite sides of the axis of rotation 435. Each deflection direction corresponds to exactly one direction of the bearing force to be carried.

[0055] Fig. Figure 10 shows an annular bearing shell 526 of a sixth embodiment of a roller bearing, wherein two different directions of deflection of the inner rotating component can be tolerated. The functional enhancement compared to the fifth embodiment is... Fig. 9 can be seen in the fact that for each direction of deflection, two different directions of the bearing force to be carried are possible. The respective components in the Fig. Ten diagonally opposite contact areas 530, 536. More precisely, the bearing shell 526 has a second contact area 530 on each side of the axis of rotation 435, which is inclined at an angle α2 relative to the first contact area 528, and whose width is at most approximately one-third of the total width of the bearing shell 526. Furthermore, the bearing shell 526 has a third contact area 536 on each opposite side of the axis of rotation 435, which is inclined at an angle α3 relative to the first contact area 528, and whose maximum width is less than one-third of the total width of the bearing shell 526. The angle α3 of the two third contact areas 536 is greater than the angle α2 of the two second contact areas 530.Viewed in the circumferential direction, the two installation areas 530, 536, which lie on a common side of the axis of rotation 435, extend approximately over the same circumferential section of the bearing shell 526.

[0056] Fig. Figure 11 shows a cross-sectional view of a bearing shell 626 according to the second embodiment of the roller bearing according to the invention in an intermediate stage of its manufacture. An outer shell 631 has been machined to a diameter that is initially larger than that which the contact area 628 of the final bearing shell 626 will have.

[0057] The reduced area 630 is produced by turning in a width l and has - unlike the first embodiment according to the preceding figures - a circular cylindrical shape.

[0058] A step is formed between the reduced area 630 and the outer shell 631, which at least in the intermediate state according to Fig. 11 has a radial flank 637. A transition 638 between the reduced area 630 and the flank 637 is rounded with a radius R. This can be, for example, 0.4 mm.

[0059] In a manufacturing step following the turning process, the bearing shell 626 is heat-treated and thus hardened.

[0060] Fig. Figure 12 shows a cross-section of a section of the finished bearing shell 626 made of Fig. 11 after heat treatment and after grinding the outer shell 631 to the dimensions of the mounting section 628. The radial flank 637 was also substantially removed. This forms an edge 633 located between the rounded transition 638 and the mounting section 628. Ideally, the rounded transition 638 is a quarter circle, so that the edge 633 is perpendicular. This edge 633 has a [missing information] compared to the first embodiments according to the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9 to Fig. 10 improved dimensional accuracy; the position of the edge 633 is less sensitive to manufacturing tolerances.

[0061] The reduced area 630 does not need to be ground, as it does not come into contact with the outer component or the housing of the axial piston machine.

[0062] In contrast to the one in the Fig. 11 and Fig. In the embodiment of the second design shown in Figure 12, a minimal remnant of the flank 637 may remain even after grinding off the outer shell 631. The advantageous rectangular shape of the edge, and thus its insensitivity to manufacturing tolerances, is thereby retained.

[0063] The Fig. 11 and Fig.Figure 12 does not show the bearing shell 626 to scale. For example, the diameter difference h between the contact area 628 and the reduced area 630 and the thickness of the ground-down outer shell 631 are significantly smaller in relation to the bearing shell 626 than shown in the figures.

[0064] A rolling bearing is disclosed in which the rollers are clamped between an inner raceway and an outer bearing shell. The outer bearing shell rests with its outer surface against an outer component, which may be the housing of an axial piston machine. The inner raceway is formed either directly on an inner component or on an inner bearing shell that rests against the inner component. To allow tilting of the inner component while maintaining predetermined contact between the rollers and the two raceways, at least one chamfered contact area or a differently reduced area is provided on the outer surface of the outer bearing shell. Reference symbol list 1 Drive shaft 2 cylinder drum 4 cylinder bore 6 pistons 8 Piston base 10 sliding shoes 12 Swivel cradle 14 Adjustment device 16 cases 18 roller bearings 20 inner taxiway 22 outer taxiway 24 rolling elements 26; 126; 226; 326; 626 circular arc bearing shell 28; 128; 228; 328; 528; 628 first investment area 30; 130; 230; 330; 530 second investment area 32 Plant area 33; 133; 233; 333; 533; 633 Rand 134; 234; 334 End section 426; 526 circular bearing shell 435; 635 Rotation axis 536 third investment area 630 reduced area 631 Outer shell 637 flank 638 rounded transition l1 Length of the rolling elements l2 Projection of the width of the second attachment area onto the mounting surface of the housing α1 Inclination angle of the inner taxiway α 1max maximum slope angle of the inner runway α2 Inclination angle of the second application area α3 Inclination angle of the third attachment area h diameter difference l width R radius

Claims

Roller bearings with two concentric circular arc-shaped roller tracks (20, 22), wherein several rolling elements (24) are accommodated between the two roller tracks (20, 22), and wherein the outer roller track (22) is formed on an outer bearing shell (26; 126; 226; 326; 626), and wherein a contact area (28; 128; 228; 328; 528; 628) is formed on the outer circumference of the outer bearing shell (26; 126; 226; 326; 626), which has the form of a section of the shell of a circular cylinder, wherein adjacent to the contact area (28; 128; 228; 328; 528; 628) a reduced area (30; 130; 230; 330; 530; 630) is formed, which The bearing area (28; 128; 228; 328; 528; 628) is inclined and / or formed by a reduced diameter compared to the bearing area (28; 128; 228; 328; 528; 628) and / or by a material removal, characterized in that the circular arc bearing shell (126; 226; 326) has end sections (134; 234;334) has, over whose respective entire width the mounting area (128; 228; 328) is formed, and wherein the reduced area (130; 230; 330) extends over a central area of ​​the bearing shell (126; 226; 326) arranged between the end sections (134; 234; 334). Roller bearing according to claim 1, wherein the contact area (28; 128; 228; 328; 528) is a first contact area, and wherein the reduced area (30; 130; 230; 330; 530) is a second contact area which is inclined to the first contact area (28; 128; 228; 328; 528). Roller bearing according to claim 2, wherein a third mounting area (536) is formed adjacent to the first mounting area (528), which is inclined to the first mounting area (528) and to the second mounting area (530). Roller bearing according to claim 3, wherein an amount of a helix angle (α2) of the second contact area (530) is not equal to an amount of a helix angle (α3) of the third contact area (536). Roller bearing according to one of the preceding claims, wherein an edge (33; 133; 233; 333; 533; 633) is formed in the transition between the contact area (28; 128; 228; 328; 528; 628) and the reduced area (30; 130; 230; 330; 530; 630), or wherein an edge (533) is formed in each of the transitions between the three areas (528, 530, 536). Roller bearing according to claim 5, wherein a step is formed at the edge (633). Roller bearing according to claim 5 or 6, wherein a rounded transition (638) is formed between the reduced area (630) and the edge (633). Roller bearings at least according to one of claims 1, 5, 6 or 7, wherein the reduced area (630) has the form of a section of a shell of a circular cylinder. Roller bearings according to one of the preceding claims, wherein the rolling elements (24) are circular cylindrical. Roller bearings according to any one of claims 1 to 8, wherein the rolling elements are convex or barrel-shaped. Roller bearing according to one of the preceding claims, wherein the contact area (28; 128; 628) and the reduced area (30; 130; 630) have at least sectionally constant width. Roller bearing according to one of the preceding claims, wherein the reduced area (30; 630) extends over the entire length of the circular arc bearing shell (26; 626). Roller bearings according to claims 11 and 12, wherein the bearing shell (26; 626) has a constant cross-section over its entire length or circumference. Roller bearings according to any one of claims 1 to 10, wherein the contact area (228; 328; 528) and the reduced area (230; 330; 530) have a changed width along a section of the length or along a section of the circumference of the bearing shell (226; 326; 426; 526). Bearing arrangement with two roller bearings according to one of the preceding claims, wherein the inner roller track (20) and the bearing shell (26; 126; 226) are arc-shaped, and wherein the respective reduced areas (30; 130; 230) are formed on the mutually facing side edges of the two bearing shells (26; 126; 226). Axial piston machine in swashplate design with a bearing arrangement according to claim 15, wherein the two inner roller tracks (20) are formed on a swashplate (12) of the axial piston machine, while the two bearing shells (26) bear against a housing (16) of the axial piston machine. Axial piston machine according to claim 16, wherein - a maximum helix angle (α1max) of the inner roller track (20), - the helix angle (α2) of the second contact area (30) relative to a contact surface (32) of the housing (16), - a length (l1) of the rolling elements (24) and - a projection (l2) of the width of the second contact area (30) onto the contact surface (32) of the housing (16) satisfy the following inequality: α 2 > arctan tan α 1max × l 1 l 2 .

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