CN219119649U - Self-aligning roller bearing - Google Patents

Abstract

The utility model provides a self-aligning roller bearing capable of smoothly guiding a retainer and suppressing noise, vibration and heat. A guide surface (22) adjacent to the axially outer side of the inner ring raceway surface (21) is opposed to a guided surface (44) formed on the flange portion (42). A shear surface (46) and a fracture surface (47) are formed on the guided surface (44). At least a part of the shearing surface (46) is a guided region (44A) guided by the guide surface (22).

Description

Self-aligning roller bearing

Technical Field

The present disclosure relates to a self-aligning roller bearing.

Background

Self-aligning roller bearings generally have the following structure: a barrel-shaped rolling element is interposed between an outer ring and an inner ring having raceway surfaces arranged in a plurality of rows. The curvature center of the track surface of the outer ring of the self-aligning roller bearing is consistent with the center of the whole bearing. Therefore, the self-aligning roller bearing has aligning property. Here, the curvature center refers to the center of a part of a spherical surface or an arc when the curved surface is regarded as the part of the spherical surface or the arc.

For example, japanese patent application laid-open No. 2014-31805 discloses a self-aligning roller bearing including a retainer having a guided surface guided by a guide surface formed on an inner ring. Here, the guided surface means a surface that is guided by a guide surface formed on the inner ring and faces the guide surface.

In the self-aligning roller bearing, a gap called a guide gap exists between the guided surface of the retainer and the guide surface of the inner ring. From the viewpoint of stabilizing the operation of the holder, suppressing noise, vibration, and heat generation, it is desirable that the guide gap is as small as possible. The position of the guide gap is determined by the positional relationship in the axial direction of the center of curvature of the guide surface and the line bisecting the guided surface in the axial direction. In general, the position of the guide gap is the end of the guided surface on the opposite side of the side where the center of curvature is located with respect to the line bisecting the guided surface in the axial direction. However, the guide clearance may be larger than the original size of the design due to conditions in the manufacturing process of the retainer. If the guide gap is larger than the design value, the retainer cannot be smoothly guided by the guided surface, and noise, vibration, and heat may increase. Japanese patent application laid-open No. 2014-31805 does not conduct any study on the above-mentioned problems.

Disclosure of Invention

The present disclosure has been made in view of the above-described problems, and an object thereof is to provide a self-aligning roller bearing capable of smoothly guiding a retainer and suppressing noise, vibration, and heat generation.

The self-aligning roller bearing of the present embodiment includes: an outer race including an outer race track surface at an inner periphery; an inner ring having a plurality of inner ring raceway surfaces and guide surfaces arranged on an outer periphery thereof; a rolling element disposed between the outer ring raceway surface and the inner ring raceway surface; and a cage which is formed with pockets that house the rolling elements and in which a plurality of pockets are arranged in the axial direction. The retainer includes: an annular portion which is disposed radially outward of the central axis and in which a pocket is formed; and a flange portion disposed radially inward of the annular portion. The guide surface adjacent to the axially outer side of the inner ring raceway surface is opposed to the guided surface formed on the flange portion. The guided surface has a shear surface and a fracture surface. At least a portion of the shear face is a guided region guided by the guide face.

The above and other objects, features, aspects and advantages of the present utility model will be understood from the following detailed description of the present utility model when taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a schematic cross-sectional view showing the structure of a self-aligning roller bearing according to each embodiment.

Fig. 2 is a schematic enlarged cross-sectional view of a region II surrounded by a broken line in fig. 1.

Fig. 3 is a schematic view showing the structure of the holder of fig. 1 and 2.

Fig. 4 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first example of embodiment 1.

Fig. 5 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second example of embodiment 1.

Fig. 6 is a schematic cross-sectional view showing a process of punching out the guided surface of the retainer according to each embodiment.

Fig. 7 is a schematic cross-sectional view showing a direction in which a guided surface of a retainer in the first example of embodiment 1 is punched.

Fig. 8 is a schematic cross-sectional view showing a direction in which a guided surface of a retainer in the second example of embodiment 1 is punched.

Fig. 9 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first comparative example of embodiment 1.

Fig. 10 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second comparative example of embodiment 1.

Fig. 11 is a schematic view showing a general appearance of a shear plane and a fracture plane.

Fig. 12 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first example of embodiment 2.

Fig. 13 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second example of embodiment 2.

Detailed Description

The present embodiment will be described below with reference to the drawings. In the drawings, the p-direction, the r-direction, and the a-direction are introduced for convenience of description. The p-direction is the circumferential direction along the rotational direction of the self-aligning roller bearing. The r direction is a radial direction extending radially from the center axis of the self-aligning roller bearing. The a-direction is an axial direction along the extending direction of the central axis of the self-aligning roller bearing.

(embodiment 1)

Fig. 1 is a schematic cross-sectional view showing the structure of a self-aligning roller bearing according to each embodiment. Fig. 2 is a schematic enlarged cross-sectional view of a region II surrounded by a broken line in fig. 1. Referring to fig. 1 and 2, a self-aligning roller bearing 100 according to the present embodiment has an annular shape centered on a central axis 110 extending in the a-direction, which is the left-right direction in the drawing. The self-aligning roller bearing 100 includes an outer race 10, an inner race 20, spherical rollers 30 as rolling elements, and a cage 40.

The outer ring 10 has an outer ring raceway surface 11 formed on an inner periphery. The outer race track surface 11 has a spherical shape. When the outer diameter of the self-aligning roller bearing 100 as a whole is large, the oil hole 12 may be provided in the central portion of the outer race 10 in the a direction. The oil hole 12 is a hole for supplying lubricating oil to the self-aligning roller bearing 100. In fig. 1 and 2, the outer race 10 appears to be bisected by the oil hole 12, but in reality has a single outer race 10 and a single outer race track surface 11. The outer ring raceway surface 11 is formed over the entire outer ring 10 in the a direction.

On the other hand, an inner ring raceway surface 21 formed on the outer periphery in a plurality of rows is arranged on the inner ring 20 disposed on the inner side in the r direction than the outer ring 10. In fig. 1 and 2, the inner race track surfaces 21 are arranged in two rows in the a direction. In fig. 1 and 2, two rows of inner race track surfaces 21 are formed on a single inner race 20. The two rows of inner race track surfaces 21 each have a spherical shape. The inner ring 20 has a plurality of guide surfaces 22 formed on the outer periphery. The guide surface 22 is formed adjacent to the outer side of the inner race track surfaces 21 in the a direction. That is, the guide surface 22 is disposed on the left side of the inner ring raceway surface 21 and on the right side of the inner ring raceway surface 21 on the left side in fig. 1 and 2. The inner race track surface 21 and the guide surface 22 are different regions. By providing the guide surface 22 outside the inner race track surface 21, it is possible for the inner race track surface 21 to avoid harmful damage from entering the inner race track surface 21 from the outside or abrasion of the inner race track surface 21 by elements from the outside.

In the cross-sectional views including the central axis 110 of fig. 1 and 2, the inner race track surface 21 and the guide surface 22 are curved. That is, the inner race track surface 21 and the guide surface 22 have a slightly curved surface shape. The guide surface 22 has the same curvature as the inner race track surface 21. The curvature here is the inverse of the radius of curvature R of fig. 4 described below. The curvatures of the inner race track surface 21 and the guide surface 22 may be identical or not identical in their entirety, and may differ by, for example, 0.1% or less. In the case where the curvature is not exactly the same but there is a subtle difference between different positions, the curvature of the inner race track surface 21 is an average value of the curvature of the whole. Similarly, in the case where there is a subtle difference in curvature between different positions, the curvature of the guide surface 22 is an average value of the curvature of the whole. The equal curvatures of the inner race track surface 21 and the guide surface 22 are not limited to the case where the curvatures are completely identical, but include the case where the error in the curvatures of both is within 1%.

In the cross-sectional views including the central axis 110 in fig. 1 and 2, the curved surface portion of the outer periphery of the inner ring 20, which is formed by combining the inner ring raceway surface 21 and the guide surface 22, has a single arc-shaped curve. That is, the inner race track surface 21 and the guide surface 22 are formed so that they are combined to form a single curve. The inner race track surface 21 and the guide surface 22 are smoothly continuous so that there is no inflection point or the like at the boundary between the both. Here, the inner race raceway surface 21 is defined as a region overlapping the spherical roller 30 in a plan view from the r direction in the outer peripheral surface of the inner race 20, and the guide surface 22 is defined as a region not belonging to the inner race raceway surface 21.

The spherical rollers 30 are arranged in plurality, and each spherical roller 30 is arranged between the outer race raceway surface 11 and the inner race raceway surface 21. That is, a part of the plurality of spherical rollers 30 is arranged between the outer ring raceway surface 11 and the inner ring raceway surface 21 of one of the two rows (left side). The other part of the plurality of spherical rollers 30 is disposed between the outer ring raceway surface 11 and the inner ring raceway surface 21 on the other (right side) of the two rows. Although not shown, a plurality of spherical rollers 30 on the left side and a plurality of spherical rollers 30 on the right side in fig. 1 and 2 are arranged at equal intervals in the p direction. The spherical roller 30 has a barrel shape (a shape close to a cylindrical shape). Specifically, the rolling surfaces of the spherical rollers 30 that contact the outer ring raceway surface 11 and the inner ring raceway surface 21 have a spherical shape, and have a pair of circular surfaces that face each other as surfaces other than the rolling surfaces.

Fig. 3 is a schematic view showing the structure of the holder of fig. 1 and 2. Referring to fig. 3 and 1 and 2, the retainer 40 is formed of generally known iron or an alloy material thereof. The holders 40 are arranged in plurality in the a direction. In fig. 1 and 2, as the holder 40, two holders 40A and 40B are arranged in the a direction. The holders 40A, 40B each have a shape close to that of the container shown in fig. 3. Specifically, the retainers 40A and 40B include an annular portion 41 and a flange portion 42, respectively. The annular portion 41 is a portion corresponding to a side surface when the retainer 40 is assumed to be container-shaped. The flange 42 is a portion corresponding to the bottom surface when the retainer 40 is assumed to be container-shaped. Therefore, in the cross-sectional views of fig. 1 and 2, the annular portion 41 is disposed on the outer side in the r direction with respect to the central axis 110 than the flange portion 42.

The annular portion 41 of the retainer 40 has a plurality of pockets 43 formed at intervals along the circumferential direction p corresponding to the annular shape of fig. 3. The pocket 43 is a hole portion formed so as to penetrate a side surface constituting the annular portion 41. Each of the plurality of pockets 43 receives one spherical roller 30. Since two holders 40 are arranged along the direction a, the pockets 43 of the holders 40A and 40B similarly receive one spherical roller 30. Accordingly, the spherical rollers 30, which are arranged at intervals in the p-direction, are arranged in the self-aligning roller bearing 100 so as to be arranged in two rows in the a-direction.

In the sectional views of fig. 1 and 2, the annular portion 41 extends substantially in the a direction. However, the annular portion 41 may be folded at the central portion in the a direction, and divided into two regions, i.e., an annular portion 41A and an annular portion 41B, which are defined by the folded position.

A part of the annular portion 41 is disposed in a region between adjacent spherical rollers 30 among the plurality of spherical rollers 30 arranged at intervals in the p-direction. The annular portion 41 of this region is a pillar portion. In fig. 1 and 2, from the viewpoint of explaining the arrangement of the column portions for each region sandwiched by the spherical rollers 30 adjacent in the p-direction, the region where the left retainer 40A overlaps the spherical roller 30 is illustrated as being arranged on the front side in the p-direction of the spherical roller 30 (therefore, the annular portion 41 is shown in solid lines). On the other hand, the region where the right retainer 40B overlaps the spherical roller 30 is illustrated as being disposed on the back side of the spherical roller 30 in the p direction (therefore, the annular portion 41 is shown by a broken line).

The flange 42 is disposed inside the annular portion 41 in the r direction. The flange 42 is a region of the annular portion 41 extending so as to protrude inward in the r direction from a position closest to the lower side (bottom) of fig. 3, and is a part of the bottom surface of fig. 3. The bottom surface of fig. 3 forming the flange portion 42 has, for example, a circular shape. A through hole is formed in a portion of the circular bottom surface so as to penetrate the bottom surface around the central axis 110. The through hole has a circular shape, for example, similar to the bottom surface of the flange 42. The flange 42 has a circular shape by forming a circular through hole in the center of the bottom surface. The inner wall surface of the through hole is a guided surface 44 shown in fig. 2. The guided surface 44 is described in detail below.

In addition, the retainer 40A and the retainer 40B are fitted so as to be close to and opposed to (in contact with) each other at the retainer end 45 of the ring portion 41, which is the uppermost portion of fig. 3, i.e., the farthest from the flange portion 42. Thus, as shown in fig. 1 and 2, the retainers 40A, 40B are incorporated. Therefore, in the self-aligning roller bearing 100, the pocket 43 and the spherical roller 30 accommodated in the pocket 43 are disposed between the outer race 10 and the inner race 20.

Fig. 4 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first example of embodiment 1. Referring to fig. 4 and 1 to 3, in the first example of the present embodiment, the guided surface 44 is the entire surface of the retainer 40 disposed at the inner periphery (position close to the central axis 110) closest to the r direction. The guided surface 44 faces the guide surface 22 formed on the outermost periphery of the inner race 20 in the r direction.

A shear surface 46 and a fracture surface 47 are formed on the guided surface 44. The shearing surface 46 and the breaking surface 47 are formed by punching the guided surface 44 as follows. The fracture surface 47 has a larger surface roughness than the shear surface 46. This is because the fracture surface 47 is formed by pulling the material such as iron constituting the guided surface 44. The shearing face 46 is a smooth face with relatively small irregularities. The shearing surface 46 is left on the trajectory of a punch or the like at the time of punching in the direction a and can be visually confirmed. In contrast, the irregularities of the fracture surface 47 are relatively large, and the error from the smooth surface is large.

The guided surface 44 is a surface whose position is guided by the opposing guide surface 22. However, the whole of the guided surface 44 may not be guided by the guide surface 22. Specifically, the position of at least a portion of the shearing surface 46 in the guided surface 44 is guided by the guide surface 22. Hereinafter, the region of the guided surface 44 at which the guide surface 22 actually guides the position is specifically referred to as a guided region 44A. In contrast, the guided surface 44 is a generic term including a region where the position is not actually guided by the guide surface 22. That is, the guided region 44A is divided into terms different from the guided surface 44. As shown in fig. 4, the entire shear surface 46 may be the guided region 44A. For example, the region having an area of 60% or more in the shearing face 46 may be designed as the guided region 44A. Alternatively, the region having an area of 80% or more of the shearing surface 46 may be the guided region 44A.

On the plane showing fig. 1, 2 and 4, a gap GP exists between the guided surface 44 and the inner ring 20. Hereinafter, a plane indicating the plane of fig. 1, 2, and 4, that is, a plane intersecting the p-direction and extending along the r-direction and the a-direction is referred to as a "cross section including the central axis 110". The gap GP represents a distance between the guided surface 44 and the inner race 20 in the r direction (i.e., the up-down direction in fig. 1, 2, and 4). The gap GP exists as a space from the inner race 20 (particularly the guide surface 22) in the entire a direction of the guided surface 44. The gap GP with the smallest interval in the r direction is the guide gap GPs. The guide gap GPs exists in the guided region 44A that is actually guided by the guide surface 22. Therefore, the guide gap GPs is a gap at a position where the size is smallest among the gaps between the guided region 44A of the shearing face 46 and the guide face 22.

The guide gap GPs is smaller than the gap GP at the boundary 44B between the shear face 46 and the fracture face 47. Thus, the guide gap GPs is generated at a position other than the boundary 44B between the shearing face 46 and the breaking face 47. Specifically, for example, in a cross section including the central axis 110 shown in fig. 4 (fig. 1), the guided surface 44 has one end 44E in the a direction and the other end 44F on the opposite side thereof. One end 44E is the left end of the guided surface 44 (the end on the adjacent spherical roller 30 side) in fig. 4, and the other end 44F is the right end of the guided surface 44 (the end on the opposite side to the adjacent spherical roller 30 side) in fig. 4. Only one shearing surface 46 and one breaking surface 47 are formed in the direction a in each of the guided surfaces 44. In fig. 4, the shearing surface 46 is formed so as to include one end 44E of the guided surface 44 in the a direction, and the breaking surface 47 is formed so as to include the other end 44F of the guided surface 44 in the a direction. Therefore, in fig. 4, one shear surface 46 is formed continuously in the a direction in the region on the relatively left side of the guided surface 44 from the one end 44E to the boundary 44B. In fig. 4, one fracture surface 47 is formed continuously in the a direction in the region on the relatively right side of the guided surface 44 from the boundary 44B to the other end 44F. The guided surface 44 has a shear surface 46 and a fracture surface 47, and the shear surface 46 is preferably larger in area ratio than the fracture surface 47. Specifically, the shearing surface 46 preferably occupies 60% or more of the entire guided surface 44, and more preferably occupies 80% or more. Accordingly, in the cross-sectional view of fig. 4, the shearing surface 46 preferably occupies 60% or more, more preferably 80% or more of the region extending in the a direction of the guided surface 44.

The guide gap GPs is generated at one end 44E of the guided surface 44 in the a direction. That is, the guide gap GPs is generated particularly at the left end of the shear plane 46 of fig. 4. In other words, the guide gap GPs is generated at the left end of the guided surface 44 in fig. 4.

In the present embodiment, the shearing surface 46 of the guided surface 44 is linear in a cross section including the central axis 110 in fig. 4 (fig. 1). That is, the shearing surface 46 has a substantially unbent planar shape. On the other hand, the fracture surface 47 is slightly away from the central axis 110, which is the upper side in the r direction, toward the other end portion 44F, as compared with the shear surface 46. Therefore, the gap GP between the fracture surface 47 and the inner ring 20 (guide surface 22) is larger than the gap GP between the shear surface 46 and the inner ring 20 (guide surface 22).

In fig. 4, the position of the shear surface 46 when the shear surface 46 is formed also in the region on the other end 44F side where the fracture surface 47 is formed is indicated by a broken line. The dashed line extends from the boundary 44B to the right in fig. 4. The broken line is a straight line that is an extension of the shear plane 46. The fracture surface 47 is located above the broken line in the r direction (on the outer peripheral side away from the central axis 110). The virtual gap GP between the virtual straight line (guided surface 44) formed by the shearing surface 46 and the virtual line indicating the assumed position and the inner ring 20 (guide surface 22) monotonously changes in the a direction. In fig. 4, the virtual gap GP increases monotonically from the left side to the right side in the a direction.

The fracture surface 47 has a rough surface and large irregularities as compared with the shear surface 46, but the fracture surface 47 is approximated to a smooth surface similar to the shear surface 46 by averaging the positions of the surfaces. In this case, the approximated smooth surface is curved at the boundary 44B (the boundary 44B is a curved portion) with respect to the shear surface 46, and becomes a straight line extending straight therefrom. The above-described smoothed surface extends with a larger slope than the shear surface 46 so as to be disposed above the other end 44F side in the r direction (on the outer peripheral side away from the central axis 110). The virtual gap GP between the inner ring 20 and the straight line (curved line) obtained by joining the above-described approximated smooth surface and the shear surface 46 also increases monotonically from the left side to the right side in the a direction.

Next, consider the center of curvature 48 of the guide surface 22 in the cross section of fig. 4 (fig. 1) including the central axis 110. In the cross section of fig. 4, the guide surface 22 has a circular arc shape having a radius of curvature R with the center of curvature 48 as the center. In fig. 4, the curvature center 48 is shown below (closer to the center axis 110) in the r-direction than the actual curvature center. In fig. 4, bisector 44C is applied. The bisector 44C is a line that bisects the guided surface 44 in the a direction (the dimension of the guided surface 44 in the a direction), and extends in the r direction. The center of curvature 48 exists on either one of the center side in the a direction of the inner ring 20 and the opposite side to the center side with respect to the bisector 44C. The center side in the a direction of the inner race 20 is a side which is sandwiched between one and the other of the spherical rollers 30 (inner race raceway surface 21) arranged in the a direction of fig. 1 and 2, and is a left side in the a direction of fig. 4. The opposite side to the center side is the outer side of the inner ring raceway surface 21 in the a direction in fig. 1 and 2, that is, the side where the guide surface 22 is disposed, and is the left and right end side away from the center side in fig. 1 and 2, and is the right side in the a direction in fig. 4. In fig. 4, the center of curvature 48 exists on the right side of the bisector 44C, i.e., on the side where the fracture surface 47 is formed. As described above, the shear surface 46 is formed on the center side (left side in fig. 4) in the a direction of the inner ring 20, and the fracture surface 47 is formed on the opposite side (right side in fig. 4) to the center side. However, a shear surface 46 may be formed in a region on the right side of the bisector 44C, particularly in a region on the left side of the bisector 44C, which is a part thereof. The shear surface 46 on the right side of the bisector 44C is elongated from the region of the shear surface 46 on the left side of the bisector 44C.

With the above, in the cross section including the center axis 110, the guided surface 44 and the guide surface 22 can be asymmetric between the center side and the opposite side of the center side in the a direction of the inner ring 20 with respect to the bisector 44C.

As described above, the curvature of the inner ring raceway surface 21 and the curvature of the guide surface 22 are equal, and the curved surface portion of the inner ring 20 formed by combining the inner ring raceway surface 21 and the guide surface 22 assumes a single arc-shaped curve. Therefore, the center of curvature 48 of the guide surface 22 can be regarded as the center of curvature 48 of the inner race track surface 21.

Fig. 5 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second example of embodiment 1. Referring to fig. 5, in the second example of the present embodiment, basically, the same structure as in fig. 2 in the case of the first example of fig. 4 is provided. Therefore, the same reference numerals are given to the same structures as those of fig. 4, and the description thereof will not be repeated.

But the following aspects of fig. 5 are different from fig. 4. In fig. 5, the guided surface 44 of the holder 40 and the curvature center 48 are turned right and left with respect to the direction a of the bisector 44C. Specifically, one end 44E is the right end (the end opposite to the adjacent spherical roller 30) of the guided surface 44 in fig. 5, and the other end 44F is the left end (the end adjacent to the spherical roller 30) of the guided surface 44 in fig. 5. Therefore, in fig. 5, one shear surface 46 is formed continuously in the direction a in the region on the right side of the guided surface 44 from the one end 44E to the boundary 44B, and at least a part of the shear surface 46 is the guided region 44A. In fig. 5, one fracture surface 47 is formed continuously in the a direction in the region on the relatively left side of the guided surface 44 from the boundary 44B to the other end 44F. Therefore, the guide gap GPs is generated at the right end of the guided surface 44 in fig. 5. In the cross section of fig. 5, the center of curvature 48 exists on the left side of the bisector 44C, i.e., on the side where the fracture surface 47 is formed. With the above-described configuration, in fig. 5, the virtual gap GP monotonously decreases from the left side to the right side in the a direction.

Next, a process of punching out the guided surface 44, in particular, of the retainer 40 of the self-aligning roller bearing 100 described above will be described.

Fig. 6 is a schematic cross-sectional view showing a process of punching out the guided surface of the retainer according to each embodiment. Fig. 7 is a schematic cross-sectional view showing a direction in which a guided surface of a retainer in the first example of embodiment 1 is punched. Referring to fig. 6 and 7, the retainer 40 (40A, 40B) is formed by partially blanking a material by the guided surface forming jig 50. The guided surface forming jig 50 includes an upper die punch 51 and a die 52. The upper die punch 51 includes a punch 53 having a punching edge. The die 52 holds the holder 40 that is to be blanked out of the guided surface 44. The outward facing side of the punch 53 includes a straight portion 54. The straight line portion 54 is a region in which the holder 40 can be machined in the a direction.

First, a container-like member to be the holder 40 is set on the die 52 as shown in fig. 6. The bottom surface, which is the lowest part when the holder 40 is viewed in fig. 3, is the lowest part of the container-like member to be the holder 40 in fig. 6. The upper die punch 51 including the punch 53 is advanced toward the center of the bottom surface in a direction F indicated by an arrow in fig. 6. Thus, a through hole is formed in the bottom surface of the holder 40. The inner wall surface of the through hole serves as a guided surface 44. The direction F indicated by the arrow in fig. 7 is the same direction as the direction F indicated by the arrow in fig. 6. Therefore, in the first example of the present embodiment, as shown in fig. 7, the guided surface 44 is formed by punching from the holder end 45 side toward the bottom surface side of the container-like member to be the holder 40. The cross-section of fig. 7 is in the same direction as the cross-section of fig. 4. Therefore, by comparing fig. 7 and 4, it can be said that the start side (upstream side) of the direction F in which the punching process is performed in the guided surface 44 becomes the shear surface 46, and the end side (downstream side) of the direction F becomes the fracture surface 47.

Fig. 8 is a schematic cross-sectional view showing a direction in which a guided surface of a retainer in the second example of embodiment 1 is punched. Referring to fig. 8, in the second example of embodiment 1, the guided surface 44 of the retainer 40 is formed by punching in the opposite direction to fig. 7. The direction F indicated by the arrow in fig. 8 is the opposite direction to the direction F indicated by the arrow in fig. 6. Therefore, in the second example of the present embodiment, as shown in fig. 8, the guided surface 44 is formed by punching from the bottom surface side of the container-like member to be the retainer 40 toward the retainer end 45 side. The cross-section of fig. 8 is in the same direction as the cross-section of fig. 5. Therefore, by comparing fig. 8 and 5, it can be said that the start side (upstream side) of the direction F in which the punching process is performed in the guided surface 44 becomes the shear surface 46, and the end side (downstream side) of the direction F becomes the fracture surface 47.

Next, the operational effects of the present embodiment will be described with reference to the comparative examples of fig. 9 and 10.

Fig. 9 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first comparative example of embodiment 1. The first comparative example is a comparative example to the first example of the present embodiment of fig. 4. Referring to fig. 9, in the first comparative example, basically, the same structure as the region a of fig. 2 in the case of the present embodiment of fig. 4 is provided. Therefore, in fig. 9, the same components as those in fig. 4 are denoted by the same reference numerals, and the description thereof will not be repeated.

However, in the first comparative example of fig. 9, each portion of the guided surface 44 is turned right and left with respect to fig. 4 in the case where the center of curvature 48 is disposed on the right side of the bisector 44C in the same manner as in fig. 4, and is the same as in the second example of fig. 5. In fig. 9, at least a part of the fracture surface 47 is the guided region 44A, and the gap GP on the fracture surface 47 side is smaller than the gap GP on the shear surface 46 side as a whole. This is because the center of curvature 48 is located on the right side of the bisector 44C, and therefore the guide surface 22 is disposed on the upper side (the outer side in the r direction) of the right side of the bisector 44C on the left side of the bisector 44C, and the distance from the guided surface 44 tends to be small.

Fig. 10 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second comparative example of embodiment 1. The second comparative example is a comparative example to the second example of the present embodiment of fig. 5. Referring to fig. 10, in the second comparative example, basically, the same structure as the region a of fig. 2 in the case of the present embodiment of fig. 5 is provided. Therefore, in fig. 10, the same components as those in fig. 5 are denoted by the same reference numerals, and the description thereof will not be repeated. However, in fig. 10, each portion of the guided surface 44 is turned right and left with respect to fig. 5 in the case where the curvature center 48 is disposed on the left side of the bisector 44C as in fig. 5, as in the first example of fig. 4. In fig. 10, at least a part of the fracture surface 47 is the guided region 44A, and the gap GP on the fracture surface 47 side is smaller than the gap GP on the shear surface 46 side as a whole.

As a result, it is difficult to determine the position and value of the guide gap GPs in fig. 9 and 10. In fig. 9, it is assumed that the guide gap GPs is generated at the left end of the guided surface 44, and the other end 44F of the portion is formed at the left end of the breaking surface 47, so that the guide gap GPs is larger than the guide gap GPs1 having the minimum size in design. Assuming that the guide gap GPs is generated at the boundary 44B of the fracture surface 47 and the shear surface 46, the guide gap GPs2 is larger than the guide gap GPs1 having the minimum size in design. In fig. 10, the left-right turn is similar to that in fig. 9.

The reason for this is as follows. The fracture surface 47 is less likely to function as the guided region 44A than the shear surface 46. Here, fig. 11 is a schematic view showing a general appearance of a shear plane and a fracture plane. Referring to fig. 11, the fracture surface 47 has a surface peeled off deeper than the shear surface 46, and has a surface roughness larger than the shear surface 46. Therefore, the guide gap formed by the fracture surface 47 at the other end 44F has a larger value than the original value, or has an unstable value (size) that is greatly changed by a slight displacement in the a direction due to the uneven shape of the fracture surface 47. Therefore, in the fracture surface 47 of fig. 9, there is a case where the increasing/decreasing tendency of the gap GP in the a-direction is opposite to that of the shear surface 46, and for example, a portion where the gap GP gradually increases toward the left side in the a-direction of the fracture surface 47 is formed. As a result, even if the gap GP between the guide surface 22 and the other end 44F, which is the left end of the guided surface 44 in fig. 9, is regarded as the guide gap, the value thereof is larger than the guide gap GPs1, which is the design value.

Further, since the gap GP tends to be larger in the region of the fracture surface 47 than in the case where the region is assumed to be the shear surface 46 as described above, there is a possibility that the position of the guide gap GPs, which is the smallest gap, is shifted to the right side than the left end portion of the guided surface 44 to be originally located. However, the amount of the offset may vary depending on how much the fracture surface 47 expands the guide gap GPs from the design value or the positions of the radius R and the center of curvature 48 of the guide surface 22 of the inner ring 20. In the case of the maximum deviation, the position of the guide gap becomes the left end portion of the shearing face 46. In this case, even if the gap GP between the boundary 44B, which is the left end of the shear surface 46, and the guide surface 22 is regarded as a guide gap, the value GPs2 is generally larger than GPs1, which is a design value. This is because, in the case of the configuration of fig. 9, a small guide gap GPs1 should be generated at the left end portion of the guided surface 44 as a design value, but the guide gap is shifted to the right, and thus the value of the gap GP is larger to the right at least in terms of design.

If the guide gap GPs becomes large, the behavior of the retainer 40 may become unstable. If the guided surface 44 having the guide gap GPs is a rough surface with large irregularities, noise, vibration, and heat may be generated in the holder 40, and use of the holder 40 may be difficult.

In view of the above problems, the self-aligning roller bearing 100 of the present embodiment includes the outer ring 10, the inner ring 20, the spherical rollers 30 as rolling elements, and the cage 40. The outer race 10 includes an outer race track surface 11 at an inner periphery. The inner race 20 has a plurality of rows of inner race raceway surfaces 21 and guide surfaces 22 arranged on the outer periphery. The spherical rollers 30 are disposed between the outer race track surface 11 and the inner race track surface 21. The retainer 40 is formed with pockets 43 for accommodating the spherical rollers 30, and a plurality of pockets are arranged in the a direction. The holder 40 includes: an annular portion 41 having a pocket 43 formed therein and disposed outside the central axis 110 in the r direction; and a flange portion 42 disposed on the inner side in the r direction with respect to the annular portion 41. The guide surface 22 adjacent to the outer side of the inner race track surface 21 in the a direction is opposed to the guided surface 44 formed on the flange portion 42. A shear surface 46 and a fracture surface 47 are formed on the guided surface 44. At least a portion of the shear face 46 is a guided region 44A guided by the guide surface 22.

When the guided surface 44 is formed by punching of the flange portion 42, the guided surface 44 is formed with a shear surface 46 and a fracture surface 47. Shear face 46 is smooth compared to fracture face 47, and has no additional surface-peeled morphology. Therefore, the shearing surface 46 is easier to control the distance from the guide surface 22 than the breaking surface 47. As a result, the cage 40 is smoothly guided by the inner ring 20, and the behavior of the cage 40 can be stabilized. Further, the surface of the guided region 44A is smoothed, and therefore noise, vibration, and heat generation can be suppressed.

In the self-aligning roller bearing 100 described above, in the cross section including the center axis 110, the smallest gap between the guided surface 44 and the inner race 20 in the r direction is the guide gap GPs between the guided region 44A of the shear surface 46 and the guide surface 22. The guide gap GPs may be smaller than the gap GP at the boundary 44B between the shear face 46 and the fracture face 47.

If the guide gap GPs is smaller than the gap GP at the boundary 44B between the shear surface 46 and the fracture surface 47, for example, the actual guide gap becomes GPs2 of fig. 9, and thus it is possible to suppress a significant increase in the guide gap compared with the design (design) value. Further, according to the present embodiment, at least a part (or the whole) of the shearing face 46 forms the guided region 44A, and the gap GP on the shearing face 46 side is smaller than the gap GP on the breaking face 47 side as a whole. Therefore, when the minimum value of the r-direction dimension between the shearing surface 46 and the inner ring 20 (guide surface 22) which can easily control the distance from the guide surface 22 becomes the guide gap GPs, the guide gap can be reduced as compared with the case where the minimum value of the r-direction dimension between the breaking surface 47 and the inner ring 20 (guide surface 22) becomes the guide gap.

As a result, the cage 40 is smoothly guided by the inner ring 20, and the behavior of the cage 40 can be stabilized. Further, compared to the case where the minimum value of the r-direction dimension between the breaking surface 47 and the inner ring 20 (guide surface 22) becomes the guide gap, the surface of the guided region 44A becomes smooth, and therefore noise, vibration, and heat generation can be suppressed.

In the self-aligning roller bearing 100 described above, the center of curvature 48 of the guide surface 22 in a cross section including the center axis 110 exists on either one of the center side in the a direction of the inner race 20 and the opposite side of the center side with respect to the bisector 44C which is a line bisecting the guided surface 44 in the a direction. At least a part of the one side is formed with a fracture surface 47, and the other side different from the one side is formed with a shear surface 46. The above structure is also possible. Specifically, a shearing surface 46 may be formed on the center side in the a direction of the guided surface 44, and a breaking surface 47 may be formed on the side (opposite side) away from the center side. For example, a shear surface 46 may be integrally formed on the left side (the other side) of fig. 4 with respect to the bisector 44C. A fracture surface 47 is formed on a portion (on a side closer to the other end portion 44F) on the right side (on a side closer to the other end portion 44F) of fig. 4 with respect to the bisector 44C, and a shear surface 46 is formed on another portion (on a side closer to the bisector 44C away from the other end portion 44F) on the right side of fig. 4 with respect to the bisector 44C.

The guided surface 44 is formed by moving a punch 53 (see fig. 6) in the a direction. In the above-described step, the position of the fracture surface 47 can be controlled according to the first condition, that is, the punching direction of the punch 53 (the direction of arrow F in fig. 6) and the second condition, that is, the positional relationship between the center of curvature 48 of the guide surface 22 and the bisector 44C. By punching in the direction F from the holder end 45 to the bottom surface as shown in fig. 7 in the first example of fig. 4, and punching in the direction F from the bottom surface to the holder end 45 as shown in fig. 8 in the second example of fig. 5, the fracture surface 47 of the guided surface 44 can be formed in a desired direction. If the first condition and the second condition are not matched, for example, if the punch 53 is moved in a direction in which the fracture surface 47 is formed on the opposite side of the center of curvature 48 from the bisector 44C, and punching is performed, the guided region 44A and the guide gap GPs in fig. 9 and 10 may be formed, and the guide gap GPs may be formed to be larger than the design value.

Accordingly, it is preferable to pay attention to matching the first condition and the above-described second condition, specifically, to perform punching by moving the punch 53 in a direction in which the fracture surface 47 is formed on the same side as the center of curvature 48 with respect to the bisector 44C in the a direction. This is because the guide surface 22 is disposed on the lower side (the inner side in the r direction) of the same side as the center of curvature 48 with respect to the bisector 44C than the opposite side to the center of curvature 48, and the distance from the guided surface 44 tends to be large. Thus, the small guide gap GPs as designed can be formed to exhibit the operational effects of the present embodiment. Therefore, by controlling the formation position of the fracture surface 47, it is possible to suppress an increase in the guide gap GPs due to the fracture surface 47, and noise, vibration, and heat generation of the guided surface 44 due to the surface roughness of the fracture surface 47.

In the self-aligning roller bearing 100, when the fracture surface 47 is present on the one side (right side of the bisector 44C in fig. 4), the center of curvature 48 may be present on the opposite side (right side of the bisector 44C in fig. 4) from the center side of the bisector 44C. This corresponds specifically to the structure of the first example of fig. 4.

In the self-aligning roller bearing 100 in which the guided surface 44 is formed by punching, as shown in fig. 7, the broken surface 47 can be provided on the same side as the curvature center 48 in fig. 4, that is, on the right side (on the opposite side to the center side in the a direction) with respect to the bisector 44C by punching from the retainer end 45 side toward the bottom surface (flange portion 42) side of the retainer. As a result, as shown in fig. 4, the gap GP between the guided surface 44 and the guide surface 22 in fig. 4 can be increased substantially gradually from the left side to the right side in the drawing (although there is a partial exception due to the uneven shape of the breaking surface 47), and the left side of the guided surface 44 in fig. 4 can be the shearing surface 46 and the right side can be the breaking surface 47. Therefore, in fig. 4, the guide gap GPs can be generated at the one end 44E of the left end of the guided surface 44 (the shearing surface 46) according to the design. The guide gap GPs has a size substantially equal to the assumed (designed) value and is a relatively small value. As a result, the cage 40 is smoothly guided by the inner ring 20, and the behavior of the cage 40 can be stabilized. Further, noise, vibration, and heat generation of the holder 40 can be suppressed.

In contrast, as shown in the second example of fig. 5, the fracture surface 47 may be present on the other side (left side of the bisector 44C in fig. 5), and the curvature center 48 may be present on the center side (left side of the bisector 44C in fig. 5) with respect to the bisector 44C. As shown in fig. 8, by punching from the bottom surface of the retainer (flange portion 42) toward the retainer end 45 side, the fracture surface 47 can be provided on the left side (the central side in the a direction) with respect to the bisector 44C, as in the curvature center 48 in fig. 5. Thus, the same operational effects as those of fig. 4 can be exerted basically in the configuration of fig. 5, although the device is turned right and left as in fig. 4.

In the self-aligning roller bearing 100, one shear surface 46 and one fracture surface 47 may be formed in the direction a. That is, for example, one shear surface 46 may be formed only in the region on the one end 44E side in the a direction and one fracture surface 47 may be formed in the region on the other end 44F side in the a direction in the guided surface 44. This is a premise for bringing about the operational effects of the features of the present embodiment described above. This is because, assuming that the plurality of shearing surfaces 46 and the breaking surfaces 47 are aligned in the a direction, there are a plurality of regions in which the gap increases and a region in which the gap decreases in the a direction, and therefore, it is difficult to control the guide gap GPs, which is the smallest gap, to be formed at the one end 44E or the like, for example. If this feature is included, it is preferable that the guide gap GPs is generated at one end 44E of the guided surface 44 in the a direction. According to the above feature, the fracture surface 47 may be formed to include the other end 44F of the guided surface 44 different from the one end 44E in the a direction. It is preferable that the gap GP between the guided surface 44 and the guide surface 22 on the center side in the a direction is smaller than the gap GP between the guided surface 44 and the guide surface 22 on the side (opposite side) away from the center in the a direction. As described above, the gap at the one end 44E on the side having the shearing surface 46 can be made smaller than the gap GP at the boundary 44B between the shearing surface 46 and the breaking surface 47, and the gap can be designed as the minimum value, that is, the guide gap GPs. Therefore, as described above, by generating the minimum gap between the shearing surface 46 and the guide surface 22 as the guide gap GPs at the one end 44E, the guide gap GPs can be made smaller according to the design value, and the retainer 40 can be driven stably. Further, the shearing surface 46 is flat, and therefore noise, vibration, and heat generation at the position of the guide gap GPs can be suppressed.

In the self-aligning roller bearing 100, when the entire guided surface 44 is assumed to be the shear surface 46 as in the cross section of fig. 4, as in the case of the extension line of the broken line from the guided surface 44, the virtual gap between the guided surface 44 and the inner race 20 can monotonously change in the a direction (monotonously increase from the left side to the right side). The above feature is also relatively easy to obtain, especially on the premise that there is one shear face 46 and one fracture face 47 in the a-direction, respectively. In addition, the action and effect are the same as those of the above-mentioned features. That is, since the gap GP is monotonically changed (increased or decreased) in the direction a, the gap at the one end 44E having the shearing surface 46 can be made smaller than the gap GP at the boundary 44B between the shearing surface 46 and the breaking surface 47, and the gap can be designed as a minimum value, that is, as the guide gap GPs. Therefore, as described above, by generating the minimum gap between the shearing surface 46 and the guide surface 22 as the guide gap GPs at the one end 44E, the guide gap GPs can be made smaller according to the design value, and the retainer 40 can be driven stably. Further, the shearing surface 46 is flat, and therefore noise, vibration, and heat generation at the position of the guide gap GPs can be suppressed.

Embodiment II

Fig. 12 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the first example of embodiment 2. Fig. 13 is a schematic enlarged cross-sectional view of a region a surrounded by a broken line in fig. 2 in the second example of embodiment 2. Referring to fig. 12, in the first example of embodiment 2, basically, the same structure as that of region a of fig. 2 in the case of the present embodiment of fig. 4 is provided. Referring to fig. 13, in the second example of embodiment 2, basically, the same structure as that of region a of fig. 2 in the case of the present embodiment of fig. 5 is provided. Therefore, in fig. 12 and 13, the same components as those in fig. 4 and 5 are denoted by the same reference numerals, and the description thereof will not be repeated.

In fig. 12 and 13, however, the shearing surface 46 in the guided surface 44 is curved in the cross section including the central axis 110 in fig. 12 and 13 (fig. 1). That is, the shearing surface 46 has a curved surface shape slightly curved as compared with a plane surface. In fig. 12 and 13, similarly to fig. 4 and 5, the position of the shear surface 46 when the shear surface 46 is formed in the region on the other end 44F side where the fracture surface 47 is formed is indicated by a broken line. The broken line is a curve as an extension of the shear plane 46. The virtual gap GP between the curved line (guided surface 44) formed by the shearing surface 46 and the broken line and the inner ring 20 (guide surface 22) monotonously changes in the a direction. Monotonically increasing from the left side to the right side in the a direction in fig. 12, and monotonically decreasing from the left side to the right side in the a direction in fig. 13.

In fig. 12 and 13, the curvature of the shearing surface 46 is equal to the curvature of an imaginary extension line constituted by a broken line. The curve obtained by combining the shearing surface 46 and the extension line formed by the broken line is a single curve, for example, a circular arc. In this regard, the relationship of the shearing face 46 to the dashed extension line is the same as the relationship of the inner race track face 21 to the guide face 22. Here, it is more preferable that the curve obtained by combining the shearing surface 46 and the extension line constituted by the broken line has the same curvature as the curve obtained by combining the inner race track surface 21 and the guide surface 22. In this way, the guided surface 44 of the retainer 40 can be processed at low cost without additional processing for adapting the guided surface 44 to the guide surface 22. As a result, the retainer 40 can be manufactured at low cost.

As in the present embodiment, the guided surface 44 may have a curved surface shape. In this case, too, the same operational effects as in the case where the guided surface 44 is planar as in embodiment 1 are exerted, and therefore, the description thereof will not be repeated here. However, in this embodiment, since the gap GP on the fracture surface 47 side is larger than that in embodiment 1, the effect of generating the guide gap GPs on the shear surface 46 side (the one end 44E side) is greater than that in embodiment 1.

The features described in the above embodiments (examples included) may be applied in a suitable combination within a range that is not technically contradictory.

It should be understood that although the specific embodiments of the present utility model have been described, the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the utility model is indicated by the appended claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Claims (10)

1. A self-aligning roller bearing, comprising:

an outer race including an outer race track surface at an inner periphery;

an inner ring having a plurality of inner ring raceway surfaces and guide surfaces arranged on an outer periphery thereof;

a rolling element disposed between the outer ring raceway surface and the inner ring raceway surface; and

a retainer formed with pockets that house the rolling elements and arranged in an axial direction,

the retainer includes: an annular portion which is disposed radially outward of the central axis and in which the pocket is formed; and a flange portion disposed on the inner side in the radial direction with respect to the annular portion,

The guide surface adjacent to the axially outer side of the inner ring raceway surface is opposed to a guided surface formed on the flange portion,

a shear surface and a fracture surface are formed on the guided surface,

at least a portion of the shear surface is a guided region guided by the guide surface.

2. The self-aligning roller bearing according to claim 1, wherein,

in a section including the central axis, a gap between the guided surface and the inner ring that is smallest in the radial direction is a guide gap between the guided region of the shearing surface and the guide surface,

the guiding gap is smaller than the gap at the boundary of the shear plane and the fracture plane.

3. The self-aligning roller bearing according to claim 2, wherein,

in the cross section, the curvature of the inner race track surface is equal to the curvature of the guide surface.

4. A self-aligning roller bearing according to claim 2 or 3, wherein,

in the cross section, the curved surface portion of the inner ring, which is formed by combining the inner ring raceway surface and the guide surface, has a curve of a single circular arc shape.

5. A self-aligning roller bearing according to claim 2 or 3, wherein,

The center of curvature of the guide surface in the cross section exists on either one of a center side of the inner ring in the axial direction and an opposite side of the center side with respect to a line bisecting the guided surface in the axial direction,

the fracture surface is formed on at least a part of the one side, and the shear surface is formed on the other side different from the one side.

6. The self-aligning roller bearing according to claim 5, wherein,

the center of curvature exists on the opposite side of the central side relative to the line that makes the bisection.

7. A self-aligning roller bearing according to claim 2 or 3, wherein,

in the axial direction, one of the shearing faces and one of the breaking faces are formed, respectively.

8. A self-aligning roller bearing according to claim 2 or 3, wherein,

the guide gap is generated at one end of the guided surface in the axial direction.

9. The self-aligning roller bearing according to claim 8, wherein,

the fracture surface is formed to include the other end portion of the guided surface different from the one end portion in the axial direction.

10. A self-aligning roller bearing according to claim 2 or 3, wherein,

When the entire guided surface is assumed to be the shearing surface, the virtual gap between the guided surface and the inner ring monotonously changes in the axial direction in the cross section.

Images