JP2023160080A - Self-aligning roller bearing - Google Patents

Abstract

To provide a self-aligning roller bearing which includes a ring body being between rollers in two rows for guiding the roller in each row in the peripheral direction, with the roller end face on one side of the roller having a convex spherical part to be guided by the ring body, for improving the handling property by eliminating the need to manage the direction of the roller.SOLUTION: Roller end faces 32, 32 on both sides are shaped in plane symmetry to a virtual plane Vp2 perpendicular to a central axis L1 of a roller 30.SELECTED DRAWING: Figure 1

Description

The present invention relates to spherical roller bearings.

Generally, a self-aligning roller bearing includes an outer ring having a concave spherical raceway surface, an inner ring having two rows of raceway surfaces, two rows of rollers interposed between the inner ring and the outer ring, and holding the rollers. and a retainer. Spherical roller bearings mainly bear radial loads, can also bear some axial loads, and have a predetermined alignment property.

Among these, self-aligning roller bearings are constructed in such a way that an annular body consisting of a guide ring or inner ring is provided between two rows of rollers, and the end face of the rollers on one side of the rollers is guided in the circumferential direction by the annular body. In order to suppress heat generation between the ring body and increase the axial load carrying capacity during bearing operation, the part of one roller end face that slides into contact with the ring body in the circumferential direction is formed into a convex spherical shape. This has been done (for example, Patent Document 1).

Japanese Patent Application Publication No. 2006-105208

However, in the rollers disclosed in Patent Document 1, the shape of the roller end face on the annular body side and the other roller end face on the opposite side is different, so it is difficult to change the direction of the rollers during the assembly process of a self-aligning roller bearing. Since it is necessary to manage the method, there is a problem that it is not easy to handle.

In view of the above-mentioned background, an object of the present invention is to improve the ease of handling by eliminating the need to manage the orientation of the rollers of a self-aligning roller bearing.

[Configuration 1]
In order to achieve the above object, the present invention provides an outer ring having a concave spherical raceway surface, an inner ring having two rows of raceway surfaces, two rows of rollers interposed between the inner ring and the outer ring, and the The ring body is provided between two rows of rollers and guides each row of rollers in the circumferential direction, and the cage holds the rollers, and the rollers have a rolling surface and roller end surfaces on both sides. In a self-aligning roller bearing in which one roller end surface has a convex spherical portion guided by the annular body, the roller end surfaces on both sides are plane symmetrical with respect to an imaginary plane perpendicular to the central axis of the roller. We adopted a configuration that has a certain shape.

According to configuration 1, the roller end faces on both sides are plane symmetrical with respect to the virtual plane perpendicular to the central axis of the roller, so even if the roller end faces on either side are assembled toward the ring body, there will be no problem between the ring body and the roller end face. It becomes possible to suppress heat generation and increase the axial load carrying capacity, and in turn, it becomes unnecessary to manage the orientation of the rollers in the assembly process, etc., thereby improving the ease of handling.

[Configuration 2]
In the above configuration 1, it is preferable that the roller end faces on both sides have a grinding relief part at the center of each. In this way, it is not necessary to grind the center portion of each roller end face, so that the machining time can be shortened and there is no need to worry about machining remaining.

[Configuration 3]
In the above configuration 2, it is preferable that the grinding relief portion is formed at a position where it cannot come into contact with the ring body. In this way, the edge serving as the boundary between the grinding relief part and the convex spherical part does not come into contact with the annular body, so that heat generation and a decrease in load carrying capacity can be suppressed compared to the case where the edge is in contact with the annular body.

[Configuration 4]
In the above structure 2 or 3, the inner ring has an outer flange that circumferentially guides a convex spherical portion of the roller end face opposite to the annular body, and the grinding relief portion cannot come into contact with the outer flange. It is good if it is formed in a suitable position. In this case, since the edge serving as the boundary between the grinding relief part and the convex spherical part does not come into contact with the outer rib, heat generation and a decrease in load carrying capacity can be suppressed compared to the case where the edge is in contact with the outer rib.

[Configuration 5]
In any one of the above configurations 1 to 4, the inner ring has an outer flange that circumferentially guides a convex spherical portion of the roller end surface opposite to the annular body, and the outer flange has a radial direction. It is preferable that the outer flange face has an outer flange face facing the convex spherical portion at an inclination angle relative to the outer ring, and the inclination angle is larger than a contact angle between the roller and the raceway surface of the outer ring. In this way, the edge, which is the outer periphery of the outer flange surface, is less likely to come into contact with the end face, so that heat generation can be suppressed compared to the case where they are in contact.

[Configuration 6]
In any one of configurations 1 to 5 above, it is preferable that the gap between the ring body and the roller end face on the ring body side is narrower than the gap between the cage and the roller end face on the ring body side. In this way, compared to the case where the relatively unstable cage guides the rollers first, the relatively stable ring body guides the rollers first, which improves the posture stability of the rollers (no skew or tilt). control), and as a result, friction and heat generation can be suppressed.

As described above, by employing the above configuration, the present invention can eliminate the need to manage the orientation of the rollers of a self-aligning roller bearing, thereby improving the ease of handling.

A sectional view showing a self-aligning roller bearing according to an embodiment of the invention Enlarged view of the vicinity of the ring in Figure 1 A cross-sectional view showing the generatrix shape of the roller end face on the outer rib side in Figure 1 Enlarged view of the area near the outer brim in Figure 1

A self-aligning roller bearing according to an exemplary embodiment of the present invention will be described based on the accompanying drawings.

This self-aligning roller bearing shown in FIG. It includes two rows of rollers 30 arranged, an annular body 40 that is provided between the two rows of rollers 30 and guides each row of rollers 30 in the circumferential direction, and a cage 50 that holds the rollers 30.

Here, FIG. 1 shows an ideal design in which the outer ring 10, the inner ring 20, the annular body 40, and the retainer 50 are located concentrically, and the rollers 30 in each row are in ideal contact with the raceway surfaces 11, 21 of the inner and outer rings. Indicates the condition. Hereinafter, the direction along the bearing center axis (not shown), which is the designed rotation center of this self-aligning roller bearing, will be referred to as the "axial direction." Also, the direction perpendicular to the bearing center axis is referred to as the "radial direction." Further, the circumferential direction around the bearing center axis is referred to as the "circumferential direction." Also, the direction along the center axis L1, which is the axis of rotation of the roller, is called the "roller axial direction," and the direction perpendicular to the roller center axis L1 is called the "roller radial direction," and the direction along the center axis L1 of the roller is called the "roller radial direction." The circumferential direction around L1 is referred to as the "roller circumferential direction."

The outer ring 10 is an annular bearing component having a concave spherical raceway surface 11 centered on the bearing center axis on its inner periphery.

The inner ring 20 is an annular bearing component having a pair of raceway surfaces 21 in two rows on the outer periphery. The inner ring 20 has a plane-symmetrical shape with respect to a virtual plane Vp1 passing through the center of its width and extending in the radial direction. The illustrated inner ring 20 further includes outer flanges 22 formed at both ends of the outer periphery of the inner ring 20 in the axial direction.

The roller 30 is a rolling element having a convex rolling surface 31, roller end surfaces 32 on both sides, and chamfered portions 33 on both sides connecting the roller end surface 32 and the rolling surface 31. Further, the rolling surface 31 has a curved shape along the concave spherical raceway surface 11.

Of the two rows of rollers 30, the first row of rollers 30 are interposed between the first raceway surface 21 and raceway surface 11, and the second row of rollers 30 are interposed between the second raceway surface 21 and raceway surface 11. intervene. During bearing rotation, the rolling surfaces 31 of the two rows of rollers 30 roll between the raceway surface 11 and the two rows of raceway surfaces 21, 21, thereby achieving a predetermined alignment.

The ring body 40 consists of a guide ring provided separately from the inner ring 20. The annular body 40 has a shape that is plane symmetrical with respect to a virtual plane (corresponding to the virtual plane Vp1 in FIG. 1) that passes through the center of its width and extends in the radial direction. In addition, instead of the guide ring, it is also possible to provide a middle collar integrally with the inner ring and to make the middle collar a ring.

The retainer 50 is made of an annular bearing component that maintains equal circumferential spacing between the rollers 30 between the raceway surfaces 11 and 21. The illustrated cage 50 is a comb-shaped machined cage that holds two rows of rollers 30. Between the cage 50 and each roller 30, gaps are set in the axial direction, radial direction, and circumferential direction. The retainer 50 is guided radially by the annulus 40.

As shown in FIG. 2, the gap δ2 between the ring body 40 and the roller end face 32 on the ring body 40 side is narrower than the gap δ1 between the cage 50 and the roller end face 32 on the ring body 40 side. The gap δ1 corresponds to the shortest distance in the roller axial direction between the cage 50 and the roller end surface 32 on the ring body 40 side in the illustrated state. The gap δ2 corresponds to the shortest distance in the roller axial direction between the ring body 40 and the roller end surface 32 on the side of the ring body 40 in the illustrated state. By setting the gap δ1>gap δ2, when the roller end face 32 on the ring body 40 side is displaced toward the ring body 40, the roller end face 32 is guided by the ring body 40 before the cage 50. It has become.

As shown in FIG. 1, the maximum diameter of the rolling surface 31 of the roller 30 is located on a virtual plane Vp2 perpendicular to the central axis of the roller 30 at the center that bisects the length of the roller 30 in the roller axial direction. do. The entire roller 30 has a plane-symmetrical shape with respect to its virtual plane Vp2. Therefore, the roller end surfaces 32 on both sides have a plane-symmetrical shape with respect to the virtual plane Vp2.

Each roller end face 32 includes a convex spherical portion 32a continuous to the chamfered portion 33, and a grinding relief portion 32b formed at the center in the radial direction of the roller.

FIG. 3 shows the shape of one roller end surface 32 (that is, the shape of the generatrix of the roller end surface 32) in a cross section on a virtual plane including the central axis L1 of the roller 30. By making the generatrix of the illustrated roller end surface 32 go around once in the roller circumferential direction, the entire surface of the roller end surface 32 is completed. Note that the generatrix shape of the roller end surface 32 on the opposite side to the roller end surface 32 shown in FIG. 3 is only a shape obtained by horizontally inverting the shape of FIG.

The convex spherical portion 32a is continuous with the chamfered portion 33 on its outer periphery, and continuous with the grinding relief portion 32b on its inner periphery. The convex spherical portion 32a is a surface portion located on an imaginary convex spherical surface, and is a line segment portion located on a single imaginary arc line passing through positions P1 and P2 on the generatrix of the roller end face 32. Positions P1 and P2 are respectively on the boundary with the chamfered portion 33, and position P1 on the outer ring 10 side is the closest to the raceway surface 11 of the outer ring 10, and position P2 on the inner ring 20 side is on the orbit of the inner ring 20. This is the position closest to surface 21. The convex spherical portion 32a is ground using a rotating grindstone.

The grinding relief portion 32b is a central portion of the roller end face 32 located closer to the virtual plane Vp2 in the roller axis direction than the virtual convex spherical surface defined by a single virtual arc passing through the positions P1 and P2. The grinding relief portion 32b has a predetermined width in the roller radial direction from the center axis L1 of the roller 30. The grinding relief portion 32b is not ground by a rotating grindstone.

When rotating the roller 30, the peripheral speed in the roller circumferential direction becomes zero at the apex (on the central axis L1) of the virtual spherical surface defining the convex spherical portion 32a, and the closer to the apex, the slower the peripheral speed becomes. For this reason, when the entire surface of the roller end face 32 is made into a convex spherical shape, there are problems in that it takes time to grind the center part and that unprocessed parts are left on the center axis L1. When the grinding relief portions 32b are formed at the center of the roller end faces 32 on both sides, these problems can be avoided.

The grinding relief portion 32b in the illustrated example has a shape recessed in the roller axis direction from the edge e1 that is the boundary between the grinding relief portion 32b and the convex spherical portion 32a, but it has a flat surface shape perpendicular to the central axis L1 of the roller 30. It is also possible to form

Among the roller end surfaces 32, 32 on both sides of the roller 30 shown in FIG. 1, the convex spherical portion 32a of the roller end surface 32 on one side becomes a portion guided in the circumferential direction by the ring body 40 during bearing operation. .

The convex spherical portion 32a is a portion formed for the purpose of suppressing heat generation between the ring bodies 40 and 30 during bearing operation and increasing the axial load carrying capacity, so friction with the ring body 40 occurs during bearing operation. It is sufficient if it is formed in the area to be obtained.

The grinding relief portion 32b is formed at a position where it cannot come into contact with the ring body 40 when it is disposed toward the ring body 40 side. Further, the grinding relief portion 32b is formed at a position where it cannot come into contact with the outer flange 22 when it is disposed toward the outer flange 22 side. When the edge e1 that is the boundary between the grinding relief part 32b and the convex spherical part 32a is on the ring body 40 side, it is at a position closer to the outer ring 10 side than the ring body 40 in the radial direction, and when it is on the outer rib 22 side , the position is closer to the outer ring 10 in the radial direction than the outer flange 22.

The outer flange 22 has an outer flange surface 22a facing in the axial direction and a convex spherical portion 32a having an inclination angle θ1 with respect to the radial direction. The inclination angle θ1 is larger than the contact angle θ2 between the rollers 30 and the raceway surface 11 of the outer ring 10. Here, the contact angle θ2 is the angle that the normal line at the point of contact between the rolling surface 31 of the rollers 30 and the raceway surface 11 of the outer ring 10 makes with a virtual plane (corresponding to the virtual plane Vp1 in FIG. 1) perpendicular to the bearing center axis. It is. Since the edge e2, which is the outer periphery of the outer flange surface 22a, moves away from the roller end surface 32 on the outer flange 22 side by the inclination angle θ1, it becomes difficult for the edge e2 of the outer flange surface 22a to come into contact with the roller end surface 32 on the outer flange 22 side. be able to. For reference, FIG. 4 shows the shape of the outer flange of a conventional example using a chain double-dashed line and compares it with the shape of the outer flange 22 shown as a solid line. In the case of the conventional example shown by the two-dot chain line, it can be seen that the distance between the edge and the end surface 32 on the outer periphery of the outer flange surface of the conventional example is the shortest distance between the outer flange and the end surface 32, and the edge contacts the roller end surface 32.

This self-aligning roller bearing shown in FIGS. 1 to 4 is as described above, and includes an outer ring 10 having a concave spherical raceway surface 11, an inner ring 20 having two rows of raceway surfaces 21, 21, Two rows of rollers 30 interposed between the inner ring 20 and the outer ring 10, an annular body 40 that is provided between the two rows of rollers 30 and guides each row of rollers 30 in the circumferential direction, and a cage that holds the rollers 30. 50, the roller 30 has a rolling surface 31 and roller end surfaces 32 on both sides, and the roller end surface 32 on one side has a convex spherical portion 32a guided by the ring body 40.

In particular, in this self-aligning roller bearing, the roller end surfaces 32, 32 on both sides are plane symmetrical with respect to the virtual plane Vp2 perpendicular to the central axis L1 of the rollers 30, so that the roller end surfaces 32 on either side can be connected to the annular body. Even when assembled toward the 40 side, the ring body 40 and the convex spherical portion 32a will come into contact with each other, so it is possible to suppress heat generation between the ring bodies 40 and 30 and increase the axial load carrying capacity. . Therefore, this self-aligning roller bearing eliminates the need to manage the orientation of the rollers 30 in the roller axial direction during the assembly process, etc., and can improve the ease of handling.

In addition, in this self-aligning roller bearing, since the roller end surfaces 32 on both sides have grinding relief portions 32b, 32b at the center of each roller end surface, grinding of the center of each roller end surface 32 is not necessary. The machining time can be shortened and there is no need to worry about machining remaining.

In addition, in this self-aligning roller bearing, the grinding relief portion 32b is formed at a position where it cannot come into contact with the ring body 40, so that the edge e1, which is the boundary between the grinding relief portion 32b and the convex spherical portion 32a, is on the ring body. 40, it is possible to suppress heat generation and a decrease in load carrying capacity compared to the case where there is contact.

Further, in this self-aligning roller bearing, the inner ring 20 has an outer flange 22 that circumferentially guides a convex spherical portion 32a of the roller end face 32 on the opposite side of the annular body 40, and a grinding relief portion 32b is formed on the outer flange. Since the edge e1, which is the boundary between the grinding relief part 32b and the convex spherical part 32a, does not come into contact with the outer flange 22, heat generation and load load are reduced compared to the case where the edge e1 is in contact with the outer flange 22. Decline in ability can be suppressed.

Further, in this self-aligning roller bearing, the inner ring 20 has an outer flange 22 that circumferentially guides a convex spherical portion 32a of the roller end face 32 on the opposite side from the annular body 40, and the outer flange 22 radially extends. On the other hand, it has an outer flange surface 22a facing the convex spherical portion 32a at an inclination angle θ1, and since the inclination angle θ1 is larger than the contact angle θ2 between the rollers 30 and the raceway surface 11 of the outer ring 10, the outer periphery of the outer flange surface 22a Since the end face 32 is less likely to come into contact with the edge e2, heat generation can be suppressed compared to the case where the end face 32 contacts the edge e2.

Further, in this self-aligning roller bearing, the gap δ2 between the ring body 40 and the roller end face 32 on the ring body 40 side is narrower than the gap δ1 between the cage 50 and the roller end face 32 on the ring body 40 side. Compared to the case where the relatively unstable cage 50 guides the rollers 30 first, the comparatively stable ring body 40 guides the rollers 30 first, so the posture stability of the rollers 30 (skew and tilt) is improved. ), and as a result, friction and heat generation can be suppressed.

Each embodiment disclosed this time should be considered to be illustrative in all respects and not restrictive. Therefore, the scope of the present invention is indicated by the claims, and it is intended that all changes within the meaning and range equivalent to the claims are included.

10 Outer ring 11 Raceway surface 20 Inner ring 21 Raceway surface 22 Outer flange 22a Outer flange surface 30 Roller 31 Rolling surface 32 Roller end surface 32a Convex spherical portion 32b Grinding relief portion 33 Chamfered portion 40 Ring body 50 Cage

Claims (6)

an outer ring having a concave spherical raceway surface, an inner ring having two rows of raceway surfaces, two rows of rollers interposed between the inner ring and the outer ring, and each row of rollers provided between the two rows of rollers. an annular body that guides the roller in the circumferential direction, and a cage that holds the roller, the roller has a rolling surface and roller end surfaces on both sides, and one roller end surface is connected to the annular body. In a spherical roller bearing having a convex spherical portion guided by
A self-aligning roller bearing, wherein the roller end faces on both sides have a plane-symmetrical shape with respect to an imaginary plane perpendicular to the central axis of the roller. The self-aligning roller bearing according to claim 1, wherein the roller end faces on both sides have a grinding relief portion at the center of each. The self-aligning roller bearing according to claim 2, wherein the grinding relief portion is formed at a position where it cannot come into contact with the ring body. The inner ring has an outer flange that circumferentially guides a convex spherical portion on an end surface of the roller opposite to the annular body, and the grinding relief portion is formed at a position where it cannot come into contact with the outer flange. A self-aligning roller bearing according to claim 2 or 3. The inner ring has an outer rib that circumferentially guides a convex spherical portion on the end surface of the roller opposite to the annular body, and the outer rib has an inclination angle with respect to the radial direction to guide the convex spherical portion on the side opposite to the annular body. The self-aligning roller bearing according to any one of claims 1 to 3, wherein the self-aligning roller bearing has outer rib surfaces facing each other, and the inclination angle is larger than the contact angle between the roller and the raceway surface of the outer ring. The self-aligning roller bearing according to any one of claims 1 to 3, wherein a gap between the ring body and the roller end face on the ring body side is narrower than a gap between the cage and the roller end face on the ring body side. .

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