Cage, rolling bearing and method for assembling a rolling bearing

Abstract

A cage 14 includes a first wall facing first end surfaces 26 of rollers 13 of a rolling bearing 10, a second wall facing second end surfaces 27 of the rollers 13, and a plurality of rods connecting the first wall and the second wall. The space between a pair of rods and between the first wall and the second wall serves as a pocket 29 that stores a roller 13. The rod includes, on one or both of the first side and the second side in a radial direction, a retaining portion that prevents the roller 13 stored in the pocket 29 from falling out. A connecting portion between the first wall and the rod includes a first concave surface 44 located on the first side in the radial direction and a second concave surface 43 located on the second side in the radial direction. The first concave surface 44 is more recessed than the second concave surface 43.

Description

Technical area

[0001] The present invention relates to cages, rolling bearings and methods for assembling a rolling bearing. State of the art

[0002] A rolling bearing includes an inner ring, an outer ring, a plurality of rolling elements, and a cage that holds the plurality of rolling elements. The cage has a plurality of pockets that store the rolling elements. A cage disclosed in Patent Document 1 includes a first annular body facing first end surfaces of rollers that are rolling elements, a second annular body facing second end surfaces of the rollers, and a plurality of rods connecting the first annular body and the second annular body. The space between a pair of rods and between the first annular body and the second annular body serves as a pocket that stores a roller. Prior art documentsPatent documents

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-143765 (JP 2021-143765 A) Summary of the inventionProblem to be solved by the invention

[0004] Fig. 21 is a perspective view showing part of a conventional cage. Fig. Fig. 22 is a diagram showing a pocket of the conventional cage when viewed from an axial direction of a roller. A cage 90 includes projections 92 as retaining portions that prevent rollers 99 stored in pockets 91 from falling out. Two projections 92 are located on a pocket 91. The dimension B between the two projections 92 is smaller than the diameter D of the roller 99. Therefore, when rollers 99 are installed in pockets 91, the rollers 99 press the projections 92, so that bars 93 of the cage 90 are elastically deformed. Stress concentration therefore occurs at connecting portions 95 between each bar 93 and each annular body 94.

[0005] To reduce stress concentration, recessed surfaces 96 are provided at the connecting portions 95 between each rod 93 and each annular body 94. The recessed surfaces 96 are formed along the entire length from an outer peripheral surface 97 to an inner peripheral surface 98 of the cage 90. Since each recessed surface 96 is formed over a large area, the connecting portions 95 have a small thickness, so the cage 90 may not have sufficient strength.

[0006] The recessed surfaces 96 also reduce the contact area between each roller 99 and each annular body 94. Each roller 99 has a recessed portion 100 radially inward from its end surface 99a due to manufacturing. The end surface 99a of each roller 99 contacts the annular body 94. However, when the recessed portion 100 is large and the recessed surfaces 96 are formed along a long length in a radial direction, the contact area between the roller 99 and the annular body 94 is small. Therefore, there is a tendency that, especially when the cage 90 is made of resin, a part of the annular body 94 is worn by contact with the end surfaces 99a of the rollers 99.

[0007] The present disclosure can reduce stress concentration occurring during installation of rollers into pockets of a cage of a rolling bearing and can reduce wear due to contact with the rollers. Means of solving the problem

[0008] A cage according to an embodiment of the present invention is a cage including a first wall facing a first end face of a roller of a rolling bearing, a second wall facing a second end face of the roller, and a plurality of bars connecting the first wall and the second wall. A space between a pair of the bars and between the first wall and the second wall serves as a pocket that stores the roller. The bar includes, on one or both of the first side and the second side in a radial direction, a retaining portion that prevents the roller stored in the pocket from falling out. A connecting portion between the first wall and the bar includes a first concave surface located on the first side in the radial direction and a second concave surface located on the second side in the radial direction.The first concave surface is more recessed than the second concave surface. Effects of the invention

[0009] The cage of the present disclosure can reduce stress concentration that occurs during installation of the rollers into the pockets of the cage and can thus reduce wear due to contact with the rollers. Brief description of the drawings [ Fig. 1] Fig. 1 is a sectional view showing an embodiment of a rolling bearing of the present invention. [ Fig. 2] Fig. 2 is a perspective view of a cage. [ Fig. 3] Fig. Figure 3 is an illustration of a roll stored in a pocket when viewed along the central axis of the roll. [ Fig. 4] Fig. 4 is the Fig. 3 shown representation without the role. [ Fig. 5] Fig. Figure 5 is an enlarged view of part of the cage. [ Fig. 6] Fig. 6 is a sectional view of a portion of a first connecting portion in which a concave arc surface is formed when viewed from a radial direction of the cage. [ Fig. 7] Fig. 7 is a sectional view of a portion of the first connecting portion where a recessed surface is formed, as viewed from the radial direction of the cage. [ Fig. 8] Fig. 8 is a perspective view showing a modification of the Fig. 5 shows the cage shown. [ Fig. 9] Fig. 9 is a diagram showing the Fig. 8, which shows a pocket when viewed along the central axis of a roller. [ Fig. 10] Fig. 10 is a sectional view showing another embodiment of the rolling bearing. [ Fig. 11] Fig. 11 is a perspective view of a cage of the Fig. 10 rolling bearing shown. [ Fig. 12] Fig. 12 is a perspective view showing a modification of the Fig. 11 shows the cage. [ Fig. 13] Fig. 13 is a sectional view showing still another embodiment of the rolling bearing. [ Fig. 14] Fig. 14 is a front view showing a part of the Fig. 13 shows the rolling bearing. [ Fig. 15] Fig. 15 is a perspective view of a cage segment. [ Fig. 16] Fig. 16 is a diagram showing a modification of the Fig. 8 shows the cage shown. [ Fig. 17] Fig. 17 is a diagram showing a modification of the Fig. 9 shows the cage. [ Fig. 18] Fig. 18 is an enlarged sectional view showing a part of the rolling bearing. [ Fig. 19] Fig. Figure 19 is a diagram showing another modification of the cage. [ Fig. 20] Fig. 20 is a diagram showing a further modification of the Fig. 11 and Fig. 12 shows the cage. [ Fig. 21] Fig. 21 is a perspective view showing part of a conventional cage. [ Fig. 22] Fig. 22 is a diagram showing a pocket of the conventional cage when viewed from an axial direction of a roller. Modes for carrying out the invention Overview of embodiments of the present invention

[0010] An overview of embodiments of the present invention is provided below. (1) A cage according to an embodiment of the present invention is a cage including a first wall facing a first end face of a roller of a rolling bearing, a second wall facing a second end face of the roller, and a plurality of bars connecting the first wall and the second wall. A space between a pair of the bars and between the first wall and the second wall serves as a pocket that stores the roller. The bar includes, on one or both of the first side and the second side in a radial direction, a retaining portion that prevents the roller stored in the pocket from falling out. A connecting portion between the first wall and the bar includes a first concave surface located on the first side in the radial direction and a second concave surface located on the second side in the radial direction.The first concave surface is more recessed than the second concave surface.

[0011] According to this cage, the roller presses the retaining portions so that the rods are elastically deformed to allow the roller to be installed in the pocket. In this case, the first concave surface can reduce stress concentration at the connecting portion. The first concave surface is present on the first side in the radial direction, but is not present on the second side in the radial direction. This configuration can provide a larger contact area between the first end surface of the roller and the first wall than in the case where the first concave surface is present along the entire length from the first side to the second side in the radial direction. Wear of the cage can therefore be reduced due to a small contact area. (2) Preferably, the first concave surface includes an inclined surface such that a clearance between the first concave surface and the roller gradually increases away from the second concave surface in the radial direction. In this case, the cage can improve the function of providing a large contact area without sacrificing the function of reducing stress concentration. (3) The cage is preferably made of resin. The first wall preferably includes a connecting surface connecting the first concave surface located on one rod of the pair of rods adjacent to each other and the first concave surface located on the other rod. The connecting surface is preferably such a surface that a clearance between the connecting surface and the roller gradually increases toward the first side in the radial direction. In this case, when the cage is molded using a mold, the mold can be easily removed toward the first side in the radial direction. (4) Preferably, the first wall is a first annular body having a ring shape, and the second wall is a second annular body having a ring shape. In this case, the cage is an annular cage having a plurality of pockets, and the roller is stored in each of the pockets. (5) Preferably, the cage is composed of a plurality of cage segments located in an annular space between an inner ring and an outer ring of the rolling bearing, and each of the cage segments includes the first wall, the second wall, and two of the rods. In this case, the cage is composed of the plurality of cage segments. (6) Preferably, an edge on the second side in the radial direction of the joint surface is closer to the first side in the radial direction than an end on the second side in the radial direction of the first concave surface located on one rod and than an end on the second side in the radial direction of the first concave surface located on the other rod. This configuration increases the area of a surface of the first wall that can contact the roller. Wear of this surface due to sliding contact of the roller can thus be prevented. (7) A rolling bearing according to an embodiment of the present invention includes: an inner ring; an outer ring; a plurality of rollers disposed between the inner ring and the outer ring; and a cage that holds the rollers. With the cage of the rolling bearing, stress concentration occurring during installation of the rollers in pockets is reduced, and wear due to contact with the rollers can be reduced. (8) A method for assembling the rolling bearing according to the embodiment of the present invention includes a combining step of installing the rollers into the pockets of one or both of the first side and the second side in the radial direction to obtain a unit of the cage and the rollers. In the combining step, the rollers are installed into the pockets in such a way that the rollers press the retaining portions to elastically deform the rods.

[0012] The above joining method reduces stress concentration that occurs during installation of the rollers into the pockets. Wear in the cage of the joined rolling bearing due to contact with the rollers is reduced. Details of embodiments of the present invention

[0013] Embodiments of the present invention are described below. First embodiment of a rolling bearing

[0014] Fig. 1 is a sectional view showing an embodiment of a rolling bearing of the present invention. A Fig. The rolling bearing 10 shown in Figure 1 is a cylindrical roller bearing and includes an inner ring 11, an outer ring 12, a plurality of rollers (cylindrical rollers) 13, and a cage 14 that holds the plurality of rollers 13. The inner ring 11 and the outer ring 12 have a ring shape. The rollers 13 are located between the inner ring 11 and the outer ring 12. The center axis of the inner ring 11 and the center axis of the outer ring coincide with each other, and these center axes are the center axis C of the rolling bearing 10.

[0015] The Fig. The cage 14 shown in Figure 1 has an annular shape. With respect to each embodiment of the present invention, a state will be described in which the center axis of the cage 14 coincides with the center axis C of the rolling bearing 10.

[0016] With respect to the inner ring 11, the outer ring 12, and the cage 14, a direction parallel to the center axis C is defined as the "axial direction." A direction perpendicular to the center axis C is defined as the "radial direction." A direction along a circle around the center axis C is defined as the "circumferential direction."

[0017] The inner ring 11 has an inner ring raceway surface 21 on its outer peripheral surface. The outer ring 12 has an outer ring raceway surface 22 on its inner peripheral surface. The outer ring 12 has ribs 23 on both sides in the axial direction of the outer ring raceway surface 22. The rollers 13 have a cylindrical shape and each include a first end surface 26, a second end surface 27, and an outer peripheral surface 28. The rollers 13 are in rolling contact with the inner ring raceway surface 21 and the outer ring raceway surface 22. The inner ring 11, the outer ring 12, and the rollers 13 are made of steel. The cage 14 is made of resin.

[0018] Fig. 2 is a perspective view of the cage 14. The cage 14 includes a first annular body 31, a second annular body 32, and a plurality of rods 33. The first annular body 31 has a ring shape and serves as a first wall facing the first end surfaces 26 of the rollers 13. The second annular body 32 has a ring shape and serves as a second wall facing the second end surfaces 27 of the rollers 13. The rods 33 connect the first annular body 31 and the second annular body 32. The rods 33 face the outer peripheral surfaces 28 of the rollers 13. The space between a pair of rods 33 adjacent to each other in the circumferential direction and between the first annular body 31 and the second annular body 32 serves as a pocket 29 that stores a roller 13.

[0019] The rods 33 each have internal retaining portions 34 on the inner peripheral side of the cage 14, which prevent the rollers 13 stored in the pockets 29 from falling out. The retaining portions 34 are protrusions each provided along a partial length in the axial direction of the rod 33 and projecting from the rod 33. Fig. 3 is a diagram of a roller 13 stored in a pocket 29 when viewed along the center axis P of the roller 13. When the roller 13 stored in the pocket 29 is displaced inward in the radial direction of the cage 14, the roller 13 comes into contact with the retaining portions 34 and is prevented from falling out.

[0020] The rods 33 each have outer retaining portions 35 on the outer peripheral side of the cage 14, which prevent the rollers 13 stored in the pockets 29 from falling out. The retaining portions 35 are projections each provided along a partial length in the axial direction of the rod 33 (see Fig. 2) and protrude from the rod 33. The outer retaining portions 35 may be omitted.

[0021] A method for assembling the rolling bearing 10, which is described in Fig. 1 is as follows. When the cage 14 is placed on the inner peripheral side of the outer ring 12, the rollers 13 are installed into the pockets 29 of the cage 14. The rollers 13 are installed from the inner peripheral side of the cage 14 into the pockets 29. As shown in Fig. As can be seen in Figure 3, when considering a pocket 29, the dimension B between the two retaining portions 34 is smaller than the diameter D of the roller 13. Therefore, when a roller 13 is installed into the pocket 29, the roller 13 presses the retaining portions 34, causing the rods 33 to be elastically deformed. All of the rollers 13 are installed in the pockets 29 of the cage 14 placed in the outer ring 12 to form an outer ring assembly. The outer ring assembly is combined with the inner ring 11 to form the rolling bearing 10.

[0022] In Fig. 2, a portion where the first annular body 31 and a rod 33 are connected is a first connecting portion 41. A portion where the second annular body 32 and a rod 33 are connected is a second connecting portion 42. When considering a unit pocket portion 15 forming a pocket 29, a roller 13 stored in this pocket 29 is sandwiched between two rods 33 in the circumferential direction of the cage 14. Therefore, there are two first connecting portions 41 in one pocket portion 15, and there are two second connecting portions 42 in one pocket portion 15.

[0023] Fig. 4 is the Fig. 3 shown representation without the roller 13. Fig. 5 is an enlarged view of a part of the cage 14. The first connecting portion 41 has a concave arc surface (second concave surface) 43 located on the outer peripheral side and a recessed surface (first concave surface) 44 located on the inner peripheral side. The concave arc surface 43 is a surface having a shape corresponding to a cylinder with a very small radius. The recessed surface 44 is a surface that is more recessed than the concave arc surface 43. The concave arc surface 43 and the recessed surface 44 are also provided in the second connecting portion 42. That is, the second connecting portion 42 has a concave arc surface 43 located on the outer peripheral side and a recessed surface 44 located on the inner peripheral side.In the present embodiment, the concave arc surface 43 of the first connecting portion 41 and the concave arc surface 43 of the second connecting portion 42 have the same shape, and the recessed surface 44 of the first connecting portion 41 and the recessed surface 44 of the second connecting portion 42 have the same shape.

[0024] The recessed surface 44 is a surface with a shape corresponding to a cone. The recessed surface 44 has an inclined surface 45 that gradually deepens the recess away from the concave arc surface 43 in the radial direction, that is, toward the inner peripheral side. A clearance e1 between the recessed surface 44 and the end surface 26 (27) of the roller 13 (see Fig. 1) becomes gradually larger towards the inner peripheral side due to the inclined surface 45.

[0025] Fig. 6 is a sectional view of a portion of the first connecting portion 41 where the concave arc surface 43 is formed, as viewed in the radial direction of the cage 14. As shown in Fig. 4 and Fig. 6, the rod 33 has a side surface 33a facing the outer peripheral surface 28 of the roller 13. The first annular body 31 has a side surface 31a facing the first end surface 26 of the roller 13. The concave arc surface 43 is a surface of a portion where the first annular body 31 and the rod 33 meet, and has a concave arc portion when viewed in the radial direction (see Fig. 6). In the Fig. 6, the side surface 33a of the rod 33 is along a tangent line at a first end 43a of the concave arc surface 43. The side surface 31a of the first annular body 31 is along a tangent line at a second end 43b of the concave arc surface 43.

[0026] Fig. Fig. 7 is a sectional view of a portion of the first connecting portion 41 where the recessed surface 44 is formed, as viewed from the radial direction of the cage 14. As shown in Fig. 4 and Fig. 7, the recessed surface 44 is a surface of a portion where the first annular body 31 and the rod 33 meet, and has a concave arc portion when viewed in the radial direction (see Fig. 7). In the Fig. 7, the side surface 33a of the rod 33 is along a tangent line at a first end 44a of the recessed surface 44. The side surface 31a of the first annular body 31 intersects a tangent line K at a second end 44b of the recessed surface 44. The recessed surface 44 is recessed from the side surface 31a of the first annular body 31 so that it is distant from the end surface 26 of the roller 13.

[0027] Fig. 8 is a perspective view showing a modification of the Fig. 5 shows the cage 14. Fig. 9 is a diagram showing the Fig. 8, which shows a pocket 29 when viewed along the central axis P of a roller 13. With regard to the Fig. 8 and Fig. 9 shown cage 14 and the one in Fig. 2 to Fig. 5, the same configurations are provided with the same reference numerals. In the cage 14 shown in Fig. 8 and Fig. 9 shown cage 14, as in the case of Fig. 2 to Fig. 5, the first connecting portion 41 has a concave arc surface 43 located on the outer peripheral side and a recessed surface 44 located on the inner peripheral side. The recessed surface 44 is a surface that is more recessed than the concave arc surface 43. The concave arc surface 43 and the recessed surface 44 are also provided in the second connecting portion 42.

[0028] The Fig. 8 and Fig. The cage 14 shown in Figure 9 differs from that shown in Fig. 2 to Fig. 5 in that the first annular body 31 has a connecting surface 46. In the cage 14 shown in Fig. 8 and Fig. In the cage 14 shown in Fig. 9, the first annular body 31 has the connecting surface 46 connecting the recessed surface 44 located on one rod 33 of a pair of rods 33 adjacent to each other in the circumferential direction and the recessed surface 44 located on the other rod 33. The connecting surface 46 is such a surface that a clearance e2 between the connecting surface 46 and the roller 13 (first end surface 26) gradually increases toward the inner peripheral side. The connecting surface 46 is a surface inclined from the side surface 31a of the first annular body 31. Like the first annular body 31, the second annular body 32 may also have a connecting surface 46. When the cage 14 is molded using a mold (injection mold), the mold can be easily removed in the radial direction due to the joining surface 46.

[0029] Fig. 16 and Fig. 17 are diagrams showing a modification of the Fig. 8 and Fig. 9 shown cage 14. The Fig. 16 and Fig. 17 differs from the form shown in Fig. 8 and Fig. 9 in the connecting surface 46, but the other configurations are the same. The same configurations are designated by the same reference numerals, and a description of the same configurations will be omitted. In the case of the Fig. 16 and Fig. 17, an outer edge 46e in the radial direction of the connecting surface 46 is located closer to the inner side in the radial direction compared to that shown in Fig. 8 and Fig. 9. The edge 46e is a section along a line where the connecting surface 46 and the side surface 31a meet.

[0030] In particular, the edge 46e of the connecting surface 46 is located radially inward from outer ends 44e in the radial direction of the recessed surface 44 located on one rod 33 and the recessed surface 44 located on the other rod 33. With this configuration, the area of the side surface 31a of the first annular body 31 that the roller 13 can contact is larger than in the case of the Fig. 8 and Fig. 9. As a result, wear of the side surface 31a can be reduced.

[0031] In the Fig. 8 and Fig. 9 and the form shown in Fig. 16 and Fig. 17, a crossing section 25 contacts the end surface 26 and the outer peripheral surface 28 of the roller 13 (see Fig. 18), the connecting surface 46 when a roller 13 is installed in a pocket 29. This facilitates installation of the roller 13 into the pocket 29. The crossing section 25 is a convexly curved section.

[0032] Fig. 19 is a diagram showing a further modification of the cage 14. In the Fig. 17, the edge 46e of the connecting surface 46 has a linear shape. In the case of the Fig. 19, the edge 46e of the connecting surface 46 has an arc shape. The arc shape is a shape corresponding to a circle concentric with an arc shape of an inner peripheral surface 31b of the first annular body 31. The Fig. 17 increases the area of the side surface 31a even more effectively. Fig. The shape shown in Figure 19 facilitates installation of the roller 13 into the pocket 29 even more effectively. The arcuate shape of the edge 46e may be an arcuate shape other than a circle, which is concentric with the arcuate shape of the inner peripheral surface 31b of the first annular body 31.

[0033] In Fig. 18, the connecting surface 46 meets the inner peripheral surface 31b of the first annular body 31. A line where these surfaces meet is an inner edge 46f in the radial direction of the connecting surface 46. In the case of the Fig. 18, the inner edge 46f of the connecting surface 46 coincides with an inner end 44f in the radial direction of the recessed surface 44. However, the present invention is not limited thereto, and the inner edge 46f of the connecting surface 46 may be located closer to the roller 13 in the axial direction than the inner end 44f of the recessed surface 44.

[0034] In each of the above forms of the cage 14, the second annular body 32 also has the same configuration as the connecting surface 46 of the first annular body 31. Second embodiment of a rolling bearing

[0035] Fig. 10 is a sectional view showing another embodiment of the rolling bearing. Fig. 10 is a tapered roller bearing and the rollers 13 provided between the inner ring 11 and the outer ring 12 are tapered rollers.

[0036] Regarding the Fig. 10 are the same configurations as those of the rolling bearing 10 shown in Fig. 1, the same reference numerals are given to the rolling bearing 10 and a description of the same configurations is omitted.

[0037] Fig. 11 is a perspective view of the cage 14 of the Fig. 10. The cage 14 includes a first annular body 31 having a large diameter, a second annular body 32 having a small diameter, and a plurality of rods 33. The first annular body 31 has a ring shape and serves as a first wall facing the first end surfaces 26 of the rollers 13. The second annular body 32 has a ring shape and serves as a second wall facing the second end surfaces 27 of the rollers 13. The rods 33 connect the first annular body 31 and the second annular body 32. The rods 33 face the outer peripheral surfaces 28 of the rollers 13. The space between a pair of rods 33 adjacent to each other in the circumferential direction and between the first annular body 31 and the second annular body 32 serves as a pocket 29 that stores a roller 13.

[0038] The rods 33 each have internal retaining portions 34 on the inner peripheral side of the cage 14, which prevent the rollers 13 stored in the pockets 29 from falling out. The retaining portions 34 are projections each provided along a partial length in the axial direction of the rod 33 and projecting from the rod 33. In the Fig. 11, the retaining portions 34 are provided at a position closer to the first annular body 31 than to the second annular body 32. When the roller 13 stored in the pocket 29 is displaced inward in the radial direction of the cage 14, the roller 13 comes into contact with the retaining portions 34 and is prevented from falling out.

[0039] A method for assembling the Fig. 10 is as follows. When the cage 14 is placed on the inner peripheral side of the outer ring 12, the rollers 13 are installed into the pockets 29 of the cage 14. The rollers 13 are installed from the inner peripheral side of the cage 14 into the pockets 29. As in the first embodiment (see Fig. 3) When considering a pocket 29, the dimension between the two retaining portions 34 is smaller than the diameter of the roller 13 at the position where these retaining portions 34 are formed. Therefore, when a roller 13 is installed into the pocket 29, the roller 13 presses the retaining portions 34, so that the rods 33 are elastically deformed. All the rollers 13 are installed into the pockets 29 of the cage 14 placed in the outer ring 12 to form an outer ring assembly. The outer ring assembly is combined with the inner ring 11 to form the rolling bearing 10. During installation, the end surface of the roller 13 is press-fitted along the first concave surface 44 using an installation jig. The roller 13 can thus be smoothly installed into the pocket 29.

[0040] In Fig. 11 is a portion where the first annular body 31 and a rod 33 are connected, a first connecting portion 41. A portion where the second annular body 32 and a rod 33 are connected is a second connecting portion 42. There are two first connecting portions 41 and two second connecting portions 42 in a pocket portion 15, which form a pocket 29. The present embodiment is also the same as the first embodiment in this point (see Fig. 2).

[0041] The first connecting portion 41 has a concave arc surface 43 located on the outer peripheral side and a recessed surface 44 located on the inner peripheral side. The concave arc surface 43 is a surface with a shape corresponding to a cylinder with a very small radius. The recessed surface 44 is a surface that is more recessed than the concave arc surface 43. In the Fig. 11, the concave arc surface 43 and the recessed surface 44 are not provided in the second connecting portion 42. However, the concave arc surface 43 and the recessed surface 44 may be provided in the second connecting portion 42.

[0042] The recessed surface 44 is a surface with a shape corresponding to a cone. The recessed surface 44 has an inclined surface 45 that gradually deepens the recess away from the concave arc surface 43 in the radial direction, that is, toward the inner peripheral side. The clearance e1 between the recessed surface 44 and the end surface 26 of the roller 13 (see Fig. 10) gradually increases toward the inner peripheral side due to the inclined surface 45. The shapes of the concave arc surface 43 and the recessed surface 44 are the same as in the first embodiment ( Fig. 6 and Fig. 7).

[0043] Fig. 12 is a perspective view showing a modification of the Fig. 11 shown cage 14. The cage shown in Fig. 12 shows a cage 14 which differs from that shown in Fig. 11 in that the first annular body 31 has a connecting surface 46. In the case of the cage 14 shown in Fig. 12, the first annular body 31 has the connecting surface 46 connecting the recessed surface 44 located on one rod 33 of a pair of rods 33 adjacent to each other in the circumferential direction and the recessed surface 44 located on the other rod 33. The connecting surface 46 is such a surface that the clearance between the connecting surface 46 and the roller 13 (first end surface 26) gradually increases toward the inner peripheral side. The connecting surface 46 is a surface inclined from the side surface 31a of the first annular body 31. The connecting surface 46 has the same configuration as the connecting surface 46 of the Fig. 8 shown cage 14.

[0044] Fig. 20 is a diagram showing a further modification of the Fig. 11 and Fig. 12 shown cage 14. The in Fig. 20 differs from the form shown in Fig. 11 and Fig. 12 in the connecting surface 46, but the other configurations are the same. The same configurations are designated by the same reference numerals, and a description of the same configurations will be omitted. In the case of the Fig. 20, the outer edge 46e in the radial direction of the connecting surface 46 is closer to the inner side in the radial direction compared to the modification shown in Fig. 12. The edge 46e is a section along a line where the connecting surface 46 and the side surface 31a meet.

[0045] In particular, the edge 46e of the connecting surface 46 is located radially inward from the outer ends 44e in the radial direction of the recessed surface 44 located on one rod 33 and the recessed surface 44 located on the other rod 33. With this configuration, the area of the side surface 31a of the first annular body 31 that the roller 13 can contact is larger than in the case of the Fig. 12. As a result, wear of the side surface 31a can be reduced. The edge 46e of the connecting surface 46 may have a linear shape or may have an arc shape, as shown in Fig. 19. In each of the above forms of the cage 14, the second annular body 32 also has the same configuration as the connecting surface 46 of the first annular body 31. Third embodiment of a rolling bearing

[0046] Fig. 13 is a sectional view showing yet another embodiment of the rolling bearing. Fig. The rolling bearing 10 shown in Figure 13 is a tapered roller bearing, and the rollers 13 provided between the inner ring 11 and the outer ring 12 are tapered rollers. Fig. 13 are the same configurations as those of the rolling bearing 10 shown in Fig. 1 are provided with the same reference numerals and a description of the same configurations is omitted. As shown in Fig. 14, the cage 14 of the rolling bearing 10 according to the third embodiment is composed of a plurality of cage segments 17. The plurality of cage segments 17 are located in an annular space S between the inner ring 11 and the outer ring 12. A roller 13 is held in one cage segment 17.

[0047] Fig. 15 is a perspective view of a cage segment 17. The cage segment 17 has a first wall 51, a second wall 52 and two bars 53. The first wall 51 faces the first end surface 26 of the roller 13 (see Fig. 13). The second wall 52 faces the second end surface 27 of the roller 13. The rods 53 connect the first wall 51 and the second wall 52. The rods 53 face the outer peripheral surface 28 of the roller 13. The space between the pair of rods 53 and between the first wall 51 and the second wall 52 serves as a pocket 29 that stores the roller 13.

[0048] The rods 53 each have, on the outer peripheral side of the cage segment 17, an outer retaining portion 35 that prevents the roller 13 stored in the pocket 29 from falling out. The retaining portion 35 is a projection protruding from the rod 53. When the roller 13 stored in the pocket 29 is displaced outward in the radial direction of the cage 14, the roller 13 comes into contact with the retaining portions 35 and is prevented from falling out. The rods 53 each have, on the inner peripheral side of the cage segment 17, an inner retaining portion 34 that prevents the roller 13 stored in the pocket 29 from falling out. The retaining portion 34 is a projection protruding from the rod 53. When the roller 13 stored in the pocket 29 is displaced inward in the radial direction of the cage 14 oris displaced, the roller 13 comes into contact with the retaining portions 34 and is prevented from falling out.

[0049] A method for assembling the rolling bearing 10, which is described in Fig. 13 is as follows. The rollers 13 are installed into the pockets 29 of the cage segments 17. The rollers 13 are installed into the pockets 29 from the outer peripheral side of the cage segments 17. When viewing a cage segment 17 (see Fig. 15), the dimension between the two outer retaining portions 35 is smaller than the diameter of the roller 13 at the position where these retaining portions 35 are formed. Therefore, when a roller 13 is installed into the pocket 29, the roller 13 presses the outer retaining portions 35, causing the rods 53 to be elastically deformed. All of the rollers 13 are installed in the cage segments 17 to form a roller and cage assembly. The roller and cage assembly is combined with the inner ring 11 and then with the outer ring 12 to form the rolling bearing 10.

[0050] In Fig. 15 is a portion where the first wall 51 and a rod 53 are connected, a first connecting portion 41. A portion where the second wall 52 and a rod 53 are connected is a second connecting portion 42. There are two first connecting portions 41 in one cage segment 17, and there are two second connecting portions 42 in one cage segment 17.

[0051] The first connecting portion 41 has a concave arc surface 43 located on the inner peripheral side and a recessed surface 44 located on the outer peripheral side. The concave arc surface 43 is a surface having a shape corresponding to a cylinder with a very small radius. The recessed surface 44 is a surface that is more recessed than the concave arc surface 43. The concave arc surface 43 and the recessed surface 44 are also provided in the second connecting portion 42. That is, the second connecting portion 42 has a concave arc surface 43 located on the inner peripheral side and a recessed surface 44 located on the outer peripheral side.The concave arc surface 43 of the first connecting portion 41 and the concave arc surface 43 of the second connecting portion 42 have the same shape, and the recessed surface 44 of the first connecting portion 41 and the recessed surface 44 of the second connecting portion 42 have the same shape.

[0052] The recessed surface 44 is a surface with a shape corresponding to a cone. The recessed surface 44 has an inclined surface 45 that gradually deepens the recess away from the concave arc surface 43 in the radial direction, that is, toward the outer peripheral side. The clearance between the recessed surface 44 and the end surface 26 (27) of the roller 13 (see Fig. 13) gradually increases toward the outer peripheral side due to the inclined surface 45. The shapes of the concave arc surface 43 and the recessed surface 44 are the same as in the first embodiment ( Fig. 6 and Fig. 7). With regard to the rolling bearing 10 and the cage 14 of each embodiment

[0053] As described above, the cage 14 of the rolling bearing 10 of each embodiment described above includes the first annular body 31 (first wall 51) facing the first end surfaces 26 of the rollers 13, the second annular body 32 (second wall 52) facing the second end surfaces 27 of the rollers 13, and the plurality of rods 33 (rods 53) connecting the first annular body 31 (first wall 51) and the second annular body 32 (second wall 52). The space between a pair of rods 33 (rods 53) and between the first annular body 31 (first wall 51) and the second annular body 32 (second wall 52) serves as a pocket 29 that stores a roller 13.

[0054] The rods 33 (rods 53) each have on a first side in the radial direction the retaining portions that prevent the roller 13 stored in the pocket 29 from falling out. In the case of the cage 14 of the first embodiment (see Fig. 3 and Fig. 4) and in the case of the cage 14 of the second embodiment (see Fig. 11), the first side in the radial direction is the inner peripheral side of the cage 14 and the second side in the radial direction is the outer peripheral side of the cage 14. In the case of the cage 14 (cage segment 17) of the third embodiment (see Fig. 15), the first side in the radial direction is the outer peripheral side of the cage 14 (cage segment 17) and the second side in the radial direction is the inner peripheral side of the cage 14 (cage segment 17).

[0055] In the cage 14 of each embodiment described above, the first connecting portion 41 between the first annular body 31 (first wall 51) and the rod 33 (rod 53) has the concave arc surface 43 located on the second side in the radial direction and the recessed surface 44 located on the first side in the radial direction. The recessed surface 44 is more recessed than the concave arc surface. The method of assembling the rolling bearing 10 including the cage 14 of each embodiment described above includes a combining step of installing the rollers 13 into the pockets 29 from the first side in the radial direction to obtain a unit of the cage 14 and the rollers 13. In the combining step, the rollers 13 press the retaining portions and elastically deform the rods 33 (rods 53) so that the rollers 13 are installed in the pockets 29.

[0056] The rods 33 (rods 53) are elastically deformed to allow the rollers 13 to be installed in the pockets 29. Even in this case, the cage 14 can reduce stress concentration at the first connecting portion 41 through the recessed surface 44. The recessed surface 44 is present on the first side in the radial direction, but is not present on the second side in the radial direction. This provides a larger contact area between the first end surface 26 of the roller 13 and the first annular body 31 (first wall 51) than in the conventional example. Wear of the cage 14 due to a reduction in the contact area can thus be reduced.

[0057] The recessed surface 44 is present on the first side in the radial direction, but is not present on the second side in the radial direction. This reduces a decrease in the strength of the cage 14. In the cage 14 of each embodiment described above, the recessed surface 44 increases the length of the portion of the rod 33 (rod 53) that is elastically deformed. This facilitates installation of the roller 13 into the pocket 29.

[0058] In the first and third embodiments, the second connecting portion 42 between the second annular body 32 (second wall 52) and the rod 33 (rod 53) has the concave arc surface 43 located on the second side in the radial direction and the recessed surface 44 located on the first side in the radial direction, like the first connecting portion 41. The recessed surface 44 is more recessed than the concave arc surface 43. This provides a larger contact area between the second end surface 27 of the roller 13 and the second annular body 32 (second wall 52) than in the conventional example.

[0059] In each of the above embodiments, the recessed surface 44 has an inclined surface 45 such that the clearance between the recessed surface 44 and the roller 13 gradually increases away from the concave arc surface 43 in the radial direction. The inclined surface 45 provides a larger contact area between the first end surface 26 of the roller 13 and the first annular body 31 (first wall 51) without sacrificing the function of reducing stress concentration. Other

[0060] In each of the above embodiments, the recessed surface (first concave surface) 44, which is continuous with the concave arc surface (second concave surface) 43, has a shape corresponding to a cone. However, the recessed surface 44 may have other shapes. Although not shown in the figures, the recessed surface 44 may have a surface with a shape corresponding to a larger cylinder than the concave arc surface 43. For example, the recessed surface 44 may be composed of a surface with a shape corresponding to a larger cylinder than the concave arc surface 43 and a surface with a shape corresponding to a cone.

[0061] In each of the above embodiments, the boundary between the concave arc surface 43 and the recessed surface 44 is located at an intermediate position in the radial direction of the first connecting portion 41 (second connecting portion 42). The concave arc surface 43 may be formed along a longer length in the radial direction than the recessed surface 44, or the recessed surface 44 may be formed along a longer length in the radial direction than the concave arc surface 43. When the concave arc surface 43 is formed along a longer length, the contact area is increased. When the recessed surface 44 is formed along a longer length, the stress concentration reducing function is improved.

[0062] As described in each of the above embodiments, the shape of the cage may vary depending on the shape of the rolling bearing, that is, depending on the rolling elements of the rolling bearing.

[0063] The above embodiments are illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the above embodiments, and is intended to include all modifications within the scope equivalent to those of the configurations described in the claims. Description of reference symbols

[0064] 10 ... rolling bearing, 11 ... inner ring, 12 ... outer ring, 13 ... roller, 14 ... cage, 17 ... cage segment, 26 ... first end surface, 27 ... second end surface, 29 ... pocket, 31 ... first annular body (first wall), 32 ... second annular body (second wall), 33 ... rod, 34 ... retaining portion, 35 ... retaining portion, 41 ... first connecting portion (connecting portion), 42 ... second connecting portion, 43 ... concave arc surface (second concave surface), 44 ... recessed surface (first concave surface), 44e ... end, 45 ... inclined surface, 46 ... connecting surface, 46e ... edge, 51 ... first wall, 52 ... second wall, 53 ... rod QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] JP 2021-143765

[0003] JP 2021-143765 A

[0003]

Claims

[1] A cage including a first wall facing a first end face of a roller of a rolling bearing, a second wall facing a second end face of the roller, and a plurality of bars connecting the first wall and the second wall, a space between a pair of the bars and between the first wall and the second wall serving as a pocket storing the roller, wherein: the rod includes on one or both of the first side and the second side, in a radial direction, a retaining portion that prevents the roll stored in the pocket from falling out; and a connecting portion between the first wall and the rod includes a first concave surface located on the first side in the radial direction and a second concave surface located on the second side in the radial direction, the first concave surface being more recessed than the second concave surface. [2] The cage according to claim 1, wherein the first concave surface includes an inclined surface such that a clearance between the first concave surface and the roller gradually increases away from the second concave surface in the radial direction. [3] Cage according to claim 2, wherein: the cage is made of resin; the first wall includes a connecting surface connecting the first concave surface located on one bar of the pair of bars that are adjacent to each other and the first concave surface located on the other bar; and the connecting surface is such a surface that a clearance between the connecting surface and the roller gradually increases toward the first side in the radial direction. [4] Cage according to one of claims 1 to 3, wherein: the first wall is a first annular body having a ring shape; and the second wall is a second annular body having a ring shape. [5] Cage according to one of claims 1 to 3, wherein: the cage is composed of a plurality of cage segments located in an annular space between an inner ring and an outer ring of the rolling bearing; and each of the cage segments contains the first wall, the second wall and two of the bars. [6] The cage according to claim 3, wherein an edge on the second side in the radial direction of the connecting surface is closer to the first side in the radial direction than an end on the second side in the radial direction of the first concave surface located on the one rod and than an end on the second side in the radial direction of the first concave surface located on the other rod. [7] Rolling bearings, comprising: an inner ring; an outer ring; a plurality of rollers located between the inner ring and the outer ring; and a cage that holds the rollers, whereby the cage is the cage according to any one of claims 1 to 6. [8] The method of assembling the rolling bearing according to claim 7, wherein the method comprises a combining step of installing the rollers into the pockets from one or both of the first side and the second side in the radial direction to obtain a unit of the cage and the rollers, wherein in the combining step, the rollers are installed into the pockets in such a manner that the rollers press the retaining portions to elastically deform the rods.

Images