Cage and cylindrical roller bearing

Abstract

To provide a holder capable of preventing concentrated wear of a part of the holder facing the rolling surface and side surface of a cylindrical roller, during skewing.SOLUTION: A column part of a holder has a first opposite surface that is a side surface facing a pocket and faces a rolling surface of a cylindrical roller. An annular part has a second opposite surface that is a side surface facing the pocket and faces a side surface of the cylindrical roller. A relief part has an R surface machined into an arc around a virtual point, a first inclined surface extending on a tangent to the R surface and extending from the R surface toward the first opposite surface, and a second inclined surface extending on the tangent to the R surface and extending from the R surface toward the second opposite surface.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a cage and a cylindrical roller bearing. [Background technology]

[0002] A bearing device is provided with a cage to arrange the rolling elements at regular intervals. Cages of various shapes have been developed in the past. One common cage has a plurality of pillars arranged between the rolling elements, two annular portions connected to both ends of each pillar, and a pocket surrounded by the two pillars and two annular portions. In this type of cage, when the rolling elements are cylindrical rollers, the cross-sectional shape of the pocket is square, and corner portions are provided at the four corners of the pocket.

[0003] Incidentally, the corners where the rolling surface and side surface of the cylindrical roller intersect are chamfered to have an R shape. Hereinafter, the chamfered corners of the cylindrical roller are referred to as chamfered portions. Similarly, the corners of the pocket are also machined to have an R shape. However, the corners of the pocket are machined with an end mill and have a larger radius of curvature than the chamfered portion of the cylindrical roller. Therefore, the corners are shaped so that they are likely to interfere with the chamfered portion. Moreover, in the cage of Patent Document 1, the corners are cut by milling and a relief portion is provided that is recessed further than the annular portion and the column portion, thereby avoiding interference between the chamfered portion and the corners. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2001-12477 A Summary of the Invention [Problem to be solved by the invention]

[0005] The cage in Patent Document 1 has corners that are sharpened toward the pocket at the connection between the recess and the annular portion and at the connection between the recess and the column portion. Therefore, when the rolling surfaces and side surfaces of the cylindrical rollers come into contact with the corners due to skew (tilt of the rotation axis of the cylindrical rollers), wear is concentrated at the contact points between the cage and the cylindrical rollers.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a retainer and a cylindrical roller bearing that can prevent concentrated wear on a portion of the retainer that faces the rolling surfaces and side surfaces of the cylindrical rollers when skewed. [Means for solving the problem]

[0007] In order to achieve the above object, a cage according to one embodiment of the present disclosure is an annular cage having a plurality of pockets in the circumferential direction for accommodating cylindrical rollers, the cage comprising a plurality of pillar portions extending in a direction parallel to the rotation axis of the cylindrical rollers, two annular portions connecting both ends of the pillar portions, and a plurality of the pockets surrounded by the pillar portions and the annular portions and provided with relief portions at four corners. The pillar portions are side surfaces facing the pockets and have a first opposing surface that faces the rolling surface of the cylindrical rollers. The first opposing surface is provided in the axial center of the pocket and extends in the axial direction. The relief portions have a first inclined surface whose distance from the rolling surface of the cylindrical rollers gradually increases as the relief portions move from the first opposing surface toward the axial outside of the pocket.

[0008] Such a shape suppresses concentrated wear on a portion of the cage that faces the rolling surfaces and side surfaces of the cylindrical rollers.

[0009] In a preferred embodiment of the cage according to the present disclosure, the annular portion has a second opposing surface that faces the pocket and faces the side surface of the cylindrical roller. The relief portion has an R surface machined into an arc shape centered on an imaginary point, a first inclined surface extending on a tangent to the R surface and extending from the R surface toward the first opposing surface, and a second inclined surface extending on a tangent to the R surface and extending from the R surface toward the second opposing surface.

[0010] According to the above configuration, the first inclined surface and the second inclined surface form a tangent to the R surface. Therefore, no corners are provided at the connection portion between the R surface and the first inclined surface and the connection portion between the R surface and the second inclined surface. This prevents concentrated wear on a portion of the cage that faces the rolling surface and side surface of the cylindrical roller.

[0011] In a preferred embodiment of the cage according to the present disclosure, a first curved surface having an R-shape is provided between the first opposing surface and the first inclined surface, and a second curved surface having an R-shape is provided between the second opposing surface and the second inclined surface.

[0012] If the first opposing surface and the first inclined surface were directly connected, a corner would be formed at the connection. However, with the above configuration, the first curved surface is interposed between the first opposing surface and the first inclined surface, and no corner is formed. This more reliably prevents concentrated wear of a portion of the cage that faces the rolling surface and side surface of the cylindrical roller.

[0013] In addition, in a retainer according to one embodiment of the present disclosure, the virtual point is located on an extension of a third virtual line connecting a first intersection point where a first virtual line extending along the first opposing surface and a second virtual line extending along the second opposing surface intersect with the center of the pocket, and a first angle formed between the first inclined surface and the first virtual line and a second angle formed between the second inclined surface and the second virtual line are the same angle.

[0014] A cylindrical roller bearing according to one aspect of the present disclosure includes any one of the cages described above, the cylindrical rollers, an inner ring, and an outer ring.

[0015] According to the cylindrical roller bearing, it is possible to suppress concentrated wear on a portion of the cage that faces the rolling surfaces and side surfaces of the cylindrical rollers.

[0016] A cylindrical roller bearing according to an embodiment of the present disclosure includes a cage, a plurality of cylindrical rollers, an inner ring, and an outer ring. When the cylindrical rollers are tilted in the circumferential direction so that the cylindrical rollers contact the column portions of the cage, the angle by which the rotation axes of the cylindrical rollers are tilted in the circumferential direction relative to when the rotation axes of the cylindrical rollers are not tilted is the same as or smaller than the first angle of the cage.

[0017] According to the cylindrical roller bearing, it is possible to suppress concentrated wear on a portion of the cage that faces the rolling surfaces and side surfaces of the cylindrical rollers. Effect of the Invention

[0018] According to the retainer and cylindrical roller bearing of the present disclosure, concentrated wear on portions of the retainer that face the rolling surfaces and side surfaces of the cylindrical rollers during skew is suppressed. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a perspective view of a cage according to the first embodiment. [Diagram 2] FIG. 2 is an enlarged view of a part of the cage according to the first embodiment, as viewed from the outer periphery side, in a case where the inner ring is not rotating relative to the outer ring. [Diagram 3] FIG. 3 is an enlarged view of the corner portion shown in FIG. [Figure 4] FIG. 4 is an enlarged view showing a part of the cage according to the first embodiment when the inner ring rotates with respect to the outer ring and the cylindrical rollers are skewed, as viewed developed from the outer peripheral side. [Diagram 5] FIG. 5 is an enlarged view of a corner of the cage according to the first modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The embodiment of the invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following description. The components described below include those that a person skilled in the art can easily imagine and those that are substantially the same. Furthermore, the components described below can be appropriately combined.

[0021] Fig. 1 is a perspective view of a cage according to embodiment 1. Fig. 2 is an enlarged view of a part of the cage according to embodiment 1, developed from the outer periphery, in a case where the inner ring is not rotating relative to the outer ring. Fig. 3 is an enlarged view of a corner shown in Fig. 2. Fig. 4 is an enlarged view of a part of the cage according to embodiment 1, developed from the outer periphery, in a case where the inner ring is rotating relative to the outer ring and the cylindrical rollers are skewed.

[0022] (Embodiment 1) The cylindrical roller bearing of the first embodiment includes a cage (see FIG. 1), a plurality of cylindrical rollers (see FIG. 2), an inner ring (not shown), and an outer ring (not shown). As shown in FIG. 1, the cage 100 of the first embodiment is an annular component having a plurality of square-shaped pockets 4 in the circumferential direction (the direction of the arrow A in FIG. 1). The material of the cage 100 is not particularly limited, and may be either metal or resin. The cage 100 is disposed between an inner ring and an outer ring in a bearing device such as a cylindrical roller bearing (not shown). Each pocket 4 accommodates a cylindrical roller 50 (see FIG. 2), which is a rolling element.

[0023] The cage 100 comprises a plurality of pillar portions 1 arranged at equal intervals in the circumferential direction, and annular portions 2, 3 connected to both ends of each pillar portion 1. In other words, the outer frame of each pocket 4 is formed by two pillar portions 1 and the annular portions 2, 3. The pillar portions 1 have first opposing surfaces 10, 11 as side surfaces facing the pocket 4. The annular portions 2, 3 have second opposing surfaces 20, 30. In the following description, the direction in which the pillar portions 1 extend will be referred to as the axial direction.

[0024] 2, the first opposing surfaces 10, 11 face a rolling surface 51 of a cylindrical roller 50 housed in the pocket 4. The second opposing surfaces 20, 30 are perpendicular to the rotation axis X of the cylindrical roller 50 and face side surfaces 52, 52 of the cylindrical roller 50 housed in the pocket 4. Recesses 40 are provided at the four corners of the pocket 4 to avoid contact with a chamfered portion 53 of the cylindrical roller 50.

[0025] As shown in FIG. 3, the relief portion 40 includes an arc-shaped (R-shaped) R surface 41, a first inclined surface 42 extending from the R surface 41 toward the first opposing surface 10, and a second inclined surface 43 extending from the R surface 41 toward the second opposing surface 20. In FIG. 3, boundary points E1 to E4 are provided to make the boundaries of the surfaces surrounding the pocket 4 easier to see. The boundary point E1 indicates the boundary between the first opposing surface 10 and the first inclined surface 42. The boundary point E2 indicates the boundary between the first inclined surface 42 and the R surface 41. The boundary point E3 indicates the boundary between the R surface 41 and the second inclined surface 43. The boundary point E4 indicates the boundary between the second inclined surface 43 and the second opposing surface 20. The first opposing surfaces 10 and 11, the second opposing surfaces 20 and 30, and the relief portion 40 will be described in detail below.

[0026] The first opposing surface 10 extends in the axial direction and is located in the center of the pocket 4 in the axial direction. The first opposing surface 10 has an axial length shorter than that of the cylindrical roller 50. The first opposing surface 11 has the same configuration as the first opposing surface 10, and therefore a description thereof will be omitted. Furthermore, L1 shown in FIG. 3 is a virtual line extending along the first opposing surface 10.

[0027] The second opposing surface 20 extends in the circumferential direction and is located in the circumferential center of the pocket 4. The second opposing surface 20 is shorter than the circumferential length of the cylindrical roller 50. Note that the second opposing surface 30 has the same configuration as the second opposing surface 20, and therefore a description thereof will be omitted. Also, L2 shown in FIG. 3 is an imaginary line extending along the second opposing surface 20.

[0028] The R surface 41 is an arc-shaped surface machined by, for example, an end mill. The R surface 41 extends along a virtual circle C1 centered on a virtual point H2. The virtual point H2 is located on an extension of a third virtual line L3 that connects a first intersection point H1 of the first virtual line L1 and the second virtual line L2 with a center O of the pocket 4. In other words, the center (virtual point H2) of the R surface 41 is located deeper than the first opposing surface 10 and the second opposing surface 20, so that the R surface 41 does not come into contact with the chamfered portion 53 (see FIG. 2) of the cylindrical roller 50. Although not particularly shown, the center O of the pocket 4 is a point where a line connecting the axial centers of the first opposing surfaces 10 and 11 and a line connecting the circumferential centers of the second opposing surfaces 20 and 30 intersect.

[0029] The first inclined surface 42 and the second inclined surface 43 are surfaces that have been machined by, for example, hailing. When the first inclined surface 42 and the second inclined surface 43 are viewed from the outer periphery side, they are tangents to the R-surface 41. Therefore, no sharp corners are provided inside the pocket 4 at the intersection between the first inclined surface 42 and the R-surface 41 (see boundary point E2) and at the intersection between the second inclined surface 43 and the R-surface 41 (see boundary point E3).

[0030] The first inclined surface 42 forms a first angle θ1 with the first virtual line L1. In other words, the first inclined surface 42 is inclined so as to move away from the rolling surface 51 of the cylindrical roller 50 (so that the distance from the rolling surface 51 of the cylindrical roller 50 gradually increases) as it moves from the first opposing surface 10 to the outside in the axial direction. According to this, as shown in FIG. 4, when the rotation axis X of the cylindrical roller 50 is inclined, a portion of the rolling surface 51 of the cylindrical roller 50 near the end in the axial direction (near the chamfered portion 53) enters the inside of the relief portion 40. Then, the portion of the rolling surface 51 of the cylindrical roller 50 near the end in the axial direction comes into contact with the first inclined surface 42. In other words, the first inclined surface 42 is inclined in the same direction as the inclined rolling surface 51, and has a shape that makes it easy to come into surface contact with the rolling surface 51.

[0031] As shown in FIG. 3, the second inclined surface 43 has a second angle θ2 with the second virtual line L2. In other words, the second inclined surface 43 is inclined so as to move away from the side surface 52 of the cylindrical roller 50 as it moves in the circumferential direction in a direction away from the second opposing surface 20. According to this, as shown in FIG. 4, when the rotation axis X of the cylindrical roller 50 is inclined, the part of the side surface 52 of the cylindrical roller 50 located closer to the column portion 1 enters the inside of the relief portion 40. Then, the radial outer part of the side surface 52 of the cylindrical roller 50 contacts the second inclined surface 43. In other words, the second inclined surface 43 is inclined in the same direction as the side surface 52, and has a shape that is easy to come into surface contact with the side surface 25.

[0032] Moreover, it is preferable that the first angle θ1 and the second angle θ2 are the same. Here, when the rotation axis X of the cylindrical roller 50 is inclined, the inclination angles of the rolling surface 51 and the side surface 52 are also the same. In other words, the first inclined surface 42 and the second inclined surface 43 are easily in surface contact with both the rolling surface 51 and the side surface 52, rather than with either one of the rolling surface 51 and the side surface 52.

[0033] In addition, the clearance 40 of the first embodiment requires less cutting of the corners of the pocket 4, and the strength of the column portion 1 can be prevented from being reduced. Therefore, in the cage 100 of the first embodiment, the circumferential thickness of the column portion 1 is relatively thin, and many cylindrical rollers 50 are arranged, improving the load capacity. In addition, as shown in FIG. 4, when the cylindrical rollers 50 are inclined in the circumferential direction so that the cylindrical rollers 50 contact the column portion 1 of the cage 100, the rolling surface 51 of the cylindrical rollers 50 is more likely to come into surface contact with the first inclined surface 42 when the angle θ3 at which the rotation axis X of the cylindrical rollers 50 is inclined in the circumferential direction is the same angle as or smaller than the first angle θ1 of the cage 100, compared to when the rotation axis X of the cylindrical rollers 50 is not inclined. Therefore, a part of the cage 100 is less likely to be worn in a concentrated manner.

[0034] As described above, the cylindrical roller bearing of the first embodiment includes a cage 100, a plurality of cylindrical rollers 50, an inner ring (not shown), and an outer ring (not shown). The cage 100 of the first embodiment is an annular cage 100 having a plurality of pockets 4 in the circumferential direction for accommodating the cylindrical rollers 50. The cage 100 includes a plurality of column sections 1 extending in a direction parallel to the rotation axis X of the cylindrical rollers 50, two annular sections 2, 3 connecting both ends of the column sections 1, and a plurality of pockets 4 surrounded by the column sections 1 and the annular sections 2, 3 and provided with relief sections 40 at the four corners. The column sections 1 are side surfaces facing the pockets 4 and have a first opposing surface 10 that faces the rolling surface 51 of the cylindrical rollers 50. The relief sections 40 have a first inclined surface 42 whose distance from the rolling surface 51 of the cylindrical rollers 50 gradually increases as the relief sections 40 move from the first opposing surface 10 toward the axial outside of the pockets 4.

[0035] The first inclined surface 42 is inclined in the same direction as the inclined rolling surface 51, and is likely to come into surface contact with the rolling surface 51. This prevents the retainer 100 and the cylindrical rollers 50 from being worn in a concentrated manner on one part.

[0036] In addition, in the first embodiment, the annular portions 2, 3 have second opposing surfaces 20, 30 which are side surfaces facing the pocket 4 and which oppose the side surface 52 of the cylindrical roller 50. The relief portion 40 has an R surface 41 machined into an arc shape centered on an imaginary point H2, a first inclined surface 42 which extends on a tangent to the R surface 41 and extends from the R surface 41 toward the first opposing surface 10, and a second inclined surface 43 which extends on a tangent to the R surface 41 and extends toward the second opposing surfaces 20, 30.

[0037] According to the retainer 100 of the first embodiment, the portion where the first inclined surface 42 and the R-surface 41 connect (see boundary point E2) and the portion where the second inclined surface 43 and the R-surface 41 connect (see boundary point E3) do not have any sharp corners in the pocket 4. Therefore, even if skew occurs, it is easy to avoid concentrated wear on a portion of the retainer that faces the rolling surfaces 51 and side surfaces 52 of the cylindrical rollers 50.

[0038] In the first embodiment, the imaginary point H2 is preferably located on an extension of a third imaginary line L that connects a first intersection point H1 where a first imaginary line L1 extending along the first opposing surface 10 and a second imaginary line L2 extending along the second opposing surfaces 20 and 30 intersect, and the center O of the pocket 4. It is preferable that a first angle θ1 formed by the first inclined surface 42 and the first imaginary line L1 and a second angle θ2 formed by the second inclined surface 43 and the second imaginary line L2 are the same angle. It is also preferable that when the cylindrical rollers 50 are inclined in the circumferential direction so that the cylindrical rollers 50 contact the column portion 1 of the cage 100, an angle θ3 at which the rotation axis X of the cylindrical rollers 50 is inclined in the circumferential direction is equal to or smaller than the first angle θ1 of the cage 100, compared to when the rotation axis X of the cylindrical rollers 50 is not inclined.

[0039] 5 is an enlarged view of a corner of the cage according to Modification 1. Next, a cage 100A according to Modification 1 will be described. The cage 100A of Modification 1 differs from the cage 100 of the first embodiment in that it is provided with a recess 40A instead of the recess 40. Hereinafter, the same components as those described in the above-mentioned first embodiment are given the same reference numerals, and redundant description will be omitted, with the description focusing on the differences.

[0040] As shown in FIG. 5, the relief portion 40A includes a rounded surface 41, a first inclined surface 42, a second inclined surface 43, a first curved surface 44, and a second curved surface 45. In FIG. 5, boundary points F1 to F6 are provided to make the boundaries of the surfaces easier to see. In detail, the boundary point F1 indicates the boundary between the first opposing surface 10 and the first curved surface 44. The boundary point F2 indicates the boundary between the first curved surface 44 and the first inclined surface 42. The boundary point F3 indicates the boundary between the first inclined surface 42 and the rounded surface 41. The boundary point F4 indicates the boundary between the rounded surface 41 and the second inclined surface 43. The boundary point F5 indicates the boundary between the second inclined surface 43 and the second curved surface 45. The boundary point F6 indicates the boundary between the second curved surface 45 and the second opposing surface 20.

[0041] In the first modification, the imaginary point H3, which is the center of the imaginary line C of the R surface 41, is provided at a position farther away from the first intersection point H1 than the imaginary point H2 in the first embodiment. Therefore, the clearance portion 40A has a larger cutting amount (recess amount) at the corner of the pocket 4 than the clearance portion 40 in the first embodiment.

[0042] The first curved surface 44 and the second curved surface 45 form an R-shape. That is, no sharp corners are provided in the pocket 4 at the intersection of the first opposing surface 10 and the first curved surface 44 (see boundary point F1), the intersection of the first curved surface 44 and the first inclined surface 42 (see boundary point F2), the intersection of the second inclined surface 43 and the second curved surface 45 (see boundary point F5), and the intersection of the second curved surface 45 and the second opposing surface 20 (see boundary point F6). This reliably makes it easy to avoid concentrated wear of a portion of the cage that faces the rolling surface 51 and the side surface 52 of the cylindrical roller 50.

[0043] Although the first embodiment and the first modification have been described above, the cage of the present disclosure is not limited thereto. For example, the first opposing surface 10 may be provided with claw portions for preventing the cylindrical rollers 50 from falling off the pockets 4. [Explanation of symbols]

[0044] 100 retainer 1 Pillar part 2, 3 Annular section 4 Pockets 10, 11 First opposing surface 20, 30 Second opposing surface 40 Relief 41 R side 42 1st slope 43 Second slope 44 1st surface 45 Second surface 50 Cylindrical roller 51 Rolling surface 52 Side 53 Chamfered part C1 Virtual circle L1 First virtual line L2 Second virtual line L3 3rd virtual line H1 1st intersection H2 Virtual point θ1 1st angle θ2 2nd angle

Claims

1. An annular cage having a plurality of pockets in a circumferential direction for accommodating cylindrical rollers, A plurality of column portions extending in a direction parallel to the rotation axis of the cylindrical roller; Two annular portions connecting both ends of the column portion; A plurality of the pockets are surrounded by the pillar portion and the annular portion, and each of the pockets has a recess at each of four corners. Equipped with the column portion has a first opposing surface which is a side surface facing the pocket and which faces a rolling surface of the cylindrical roller, The first opposing surface is provided at a center portion of the pocket in the axial direction and extends in the axial direction, the relief portion has a first inclined surface whose distance from the rolling surface of the cylindrical roller gradually increases as the relief portion moves from the first opposing surface toward the axial outside of the pocket, the annular portion has a second opposing surface which is a side surface facing the pocket and which faces a side surface of the cylindrical roller, The recessed portion has a rounded surface that is machined into an arc shape centered on a virtual point, a first inclined surface that extends on a tangent to the rounded surface and from the rounded surface toward the first opposing surface, and a second inclined surface that extends on a tangent to the rounded surface and from the rounded surface toward the second opposing surface. retainer.

2. A first curved surface having an R-shape is provided between the first opposing surface and the first inclined surface, A second curved surface having an R-shape is provided between the second opposing surface and the second inclined surface. The cage of claim 1 .

3. the imaginary point is located on an extension of a third imaginary line that connects a first intersection point where a first imaginary line extending along the first opposing surface and a second imaginary line extending along the second opposing surface intersect, and a center of the pocket; A first angle formed between the first inclined surface and the first virtual line and a second angle formed between the second inclined surface and the second virtual line are equal to each other. The cage according to claim 1 or 2.

4. The cage according to any one of claims 1 to 3, a plurality of cylindrical rollers, an inner ring, and an outer ring. Cylindrical roller bearing.

5. A cage comprising the cage according to claim 3, a plurality of cylindrical rollers, an inner ring, and an outer ring, When the cylindrical rollers are tilted in the circumferential direction so that the cylindrical rollers come into contact with the column portions of the cage, the angle by which the rotation axis of the cylindrical rollers is tilted in the circumferential direction with respect to when the rotation axis of the cylindrical rollers is not tilted is the same angle as the first angle of the cage or is smaller than the first angle. Cylindrical roller bearing.

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