JP7353067B2 - bearing device - Google Patents

Description

The present invention relates to a bearing device in which a rolling bearing is interposed between a shaft and a housing.

A bearing ring of a rolling bearing that receives a radial load acting between the shaft and the housing is fitted onto the outer periphery of the shaft or the inner periphery of the housing. The fitting surfaces formed on the raceway, shaft, and housing are usually cylindrical. The fit between the fitting surface formed on the inner or outer periphery of the bearing ring and the fitting surface formed on the shaft or housing is determined by interference fit, taking into consideration load conditions, ease of assembly of the device, etc. Select from normal fit or clearance fit. A loosely fitted raceway ring may creep, ie, become circumferentially misaligned with respect to its mating partner, the shaft or housing.

For example, in a bearing device that supports the shaft of an automobile transmission in a housing via a rolling bearing, the outer raceway of the rolling bearing is loosely fitted into the housing in order to facilitate assembly into the housing. For this reason, the outer raceway ring may creep due to unbalanced loads on the shaft during heavy loads or high-speed rotation.

It is known that the mechanism of creep is that a traveling wave is generated on the surface of the raceway, and the traveling wave causes the raceway itself to move. That is, when the rolling element load acts on the raceway surface of the raceway ring, the surface of the raceway protrudes directly below it and becomes wavy. When the bearing rotates, the rolling elements also revolve, and the undulations on their surfaces become traveling waves. The traveling waves generated on the surface of the bearing ring exhibit peristaltic behavior in the circumferential and radial directions over the load area of the rolling bearing. The traveling wave attempts to transport the mating member in the direction opposite to the direction of revolution of the rolling element, but it is pushed back by the resistance of the mating member (shaft or housing), and as a result, the bearing ring moves in the direction of revolution of the rolling element. In other words, creep occurs in which the bearing rotates in the same direction as the rotation.

In order to suppress creep due to such a mechanism, grooves have conventionally been formed in the bearing ring or a mating member (shaft or housing) to which the bearing ring is fitted (Patent Documents 1 to 3). .

In the bearing device of Patent Document 1, a groove portion is formed that extends from the fitting surface of the bearing ring or the mating member to a depth in the radial direction and continues all the way in the circumferential direction.

In the bearing devices of Patent Documents 2 and 3, a groove for suppressing creep is not formed in the bearing ring, but a groove is formed only in the housing. The groove has a finite groove bottom surface that is shorter than the circumferential length of the mating surface of the housing.

The groove portions disclosed in Patent Document 1 and the like suppress the traveling waves of the bearing ring from being transmitted to the mating member in the load range of the bearing ring that receives a radial load, thereby suppressing the occurrence of creep.

Patent No. 4466473 Japanese Patent Application Publication No. 2017-137896 Japanese Patent Application Publication No. 2009-174556

However, if the groove is formed around the entire circumference of the bearing ring as in Patent Document 1, even if the direction of the radial load fluctuates due to an unbalanced load on the shaft, the groove will always be located in the load area, which will reduce the creep suppression effect. This is particularly good, but on the other hand, there is a concern that the strength of the bearing ring may decrease.

On the other hand, when grooves are partially formed in the circumferential direction on a mating member such as a housing as in Patent Documents 2 and 3, if the direction of the radial load applied to the rolling bearing does not match the position of the groove, the creep suppression effect is There are times when you may not be able to fully demonstrate your abilities. For example, if the radial load is a static load and the direction of the load does not match the position of the groove, or if the direction of the radial load fluctuates due to an unbalanced load on the shaft, etc., the groove may be located within the load area. Therefore, the creep suppressing effect may not be exhibited.

In view of the above-mentioned background, the problem to be solved by the present invention is to determine the direction of the radial load applied to the rolling bearing and the direction of the groove in a bearing device in which the bearing ring of the rolling bearing is loosely fitted to a mating member such as a shaft or a housing. The objective is to suppress a decrease in the strength of the bearing ring while making it possible to suppress creep in the groove portion of the bearing ring even when the positions do not match.

In order to achieve the above object, the present invention includes a shaft, a housing surrounding the shaft, and a rolling bearing interposed between the shaft and the housing, the rolling bearing having a plurality of rolling elements, a bearing ring that is loosely fitted to a mating member that is either one of the shaft and the housing; the bearing ring has a raceway surface serving as a running path for the rolling elements; In a bearing device in which a mating member has a fitting surface extending in the circumferential direction, the bearing ring has a groove portion extending in the circumferential direction with a radial depth from the fitting surface at a position directly below the raceway surface in the radial direction. , and the groove portion is formed to have a finite length in the circumferential direction.

According to the above configuration, when the direction of the radial load applied to the rolling bearing matches the position of the groove, the groove suppresses the wave-like deformation of the bearing ring due to the radial load from being transmitted to the mating member as a traveling wave, thereby causing creep. can be suppressed. Even if the direction of the radial load does not match the position of the groove, the bearing ring creeps and the position of the groove matches, so that creep can be suppressed. Since the groove is formed to have a finite length in the circumferential direction, a reduction in strength of the bearing ring can be suppressed compared to a case where the groove is formed all around the circumference.

For example, the groove portion is formed so as to leave a radial gap with the mating member in the load range when the maximum radial load is applied within the range of radial loads applied to the rolling bearing. Good to have. In this way, the wave-like deformation of the groove bottom surface of the groove portion does not come into contact with the fitting surface of the mating member, and wear of the groove bottom surface does not occur, so that a decrease in the wall thickness between the raceway surface and the groove portion can be avoided.

Further, the rolling element is made of a ball, the width center of the groove is located directly below the width center of the raceway surface in the radial direction, and the width of the groove is equal to or less than the width of the raceway surface, It is preferable that the length be set to be greater than or equal to the major axis of the contact ellipse between the raceway surface and the rolling element when a maximum radial load is applied within the range of radial loads applied to the rolling bearing. When the rolling bearing is a ball bearing, the point contact between the balls as rolling elements and the raceway surface is elliptical, but normally the contact ellipse does not protrude from the raceway surface. Therefore, if the width center of the groove is located directly below the width center of the raceway surface in the radial direction, wave-like deformation due to the radial load can be caused in the groove. Here, the width of the groove is less than or equal to the width of the raceway surface, and is greater than or equal to the major axis of the contact ellipse between the raceway surface and the rolling elements when the maximum radial load is applied within the range of radial loads applied to the rolling bearing. For example, it is possible to suppress creep in the groove while avoiding excessive wave-like deformation of the bearing ring due to radial load in the fitting region between the bearing ring and the mating member on both sides of the groove.

Further, when H is the minimum thickness of the raceway in the radial direction between the raceway surface and the fitting surface of the raceway, and δ is the radial depth of the groove, 0.005H≦δ≦0.1H It is good that it is set to . The larger the minimum raceway ring thickness H, the smaller the wave-like deformation caused by radial load, which is advantageous in suppressing creep, but as the bearing size increases, it is necessary to increase the minimum raceway ring thickness H. There is a limit. As the radial depth δ of the groove becomes smaller relative to the minimum raceway ring wall thickness H, the creep suppression effect cannot be expected, and as it becomes larger, the deflection and stress near the groove of the raceway due to radial load increases. . In order to obtain a shape that suppresses deflection and stress, it is preferable to satisfy the relationship 0.005H≦δ≦0.1H.

Further, when the groove is formed only at one location in the circumferential direction of the bearing ring, α is an angle that defines the length of the groove in the circumferential direction, and θ is an angle that defines the rolling element pitch. , 0.5θ≦α≦θ. In order to suppress a decrease in the strength of the bearing ring, it is preferable to reduce the number of grooves as much as possible, and it is also preferable to make the length of the grooves in the circumferential direction as short as possible. When a radial load is applied to a rolling bearing, the wave-like deformation of the bearing ring occurs at its maximum at a position directly below the contact point between the rolling element and raceway surface in the direction of the radial load, and from this position. The further apart in the circumferential direction, the smaller it becomes. If the angle α that defines the circumferential length of the groove is less than 0.5 times the angle θ that defines the rolling element pitch, it may be insufficient to suppress creep; When the angle θ exceeds 1 time, the contribution to creep suppression decreases. For these reasons, it is preferable that the groove portion be limited to one location in the circumferential direction and that 0.5θ≦α≦θ.

Moreover, it is preferable that the mating member is a housing. In this case, since the groove is formed on the outer periphery of the bearing ring, there is no need to process an undercut groove on the inner periphery of the housing, and the manufacturing of the housing does not become difficult.

As described above, the present invention provides a bearing device in which a bearing ring of a rolling bearing is loosely fitted into a mating member such as a shaft or a housing by employing the above configuration, in which the direction of the radial load applied to the rolling bearing and the position of the groove portion are fixed. Even if they do not match, creep can be suppressed in the grooves of the bearing ring, and a decrease in the strength of the bearing ring can be suppressed.

A front view showing a bearing device according to an embodiment of the invention Cross-sectional view taken along line II-II in Figure 1 A perspective view showing the entire rolling bearing according to the embodiment. Enlarged view of the bearing ring near the groove in Figure 2

A bearing device according to an exemplary embodiment of the present invention will be described based on the accompanying drawings.

As shown in FIGS. 1 and 2, a bearing device according to an embodiment of the present invention includes a shaft 1, a housing 2 surrounding the shaft 1, and a rolling bearing 3 interposed between the shaft 1 and the housing 2. .

Hereinafter, in an ideal state where the designed rotation center line of the rolling bearing 3 and the rotation center line of the shaft 1 coincide, the direction along the rotation center will be referred to as the "axial direction." Further, the direction along the circumference that goes around the center line of rotation is referred to as the "circumferential direction." Further, the direction perpendicular to the center line of rotation is referred to as the "radial direction."

The shaft 1 rotates relative to the housing 2. The shaft 1 is, for example, a transmission shaft included in an automobile transmission.

The shaft 1 has a fitting surface 1a extending in the circumferential direction. This fitting surface 1a is formed into a cylindrical surface concentric with the rotation center line of the shaft 1.

The housing 2 is stationary with respect to the shaft 1 and supports the rolling bearing 3 in the radial direction. The housing 2 is, for example, a bulkhead formed as a part of a transmission case of an automobile.

The housing 2 has a fitting surface 2a that extends in the circumferential direction. The fitting surface 2a is formed into a cylindrical shape that surrounds the fitting surface 1a of the shaft 1 from the outside. The center line of the fitting surface 2a is set to be concentric with the rotation center line of the shaft 1.

The rolling bearing 3 rotatably supports the shaft 1 relative to the housing 2. During operation of this bearing device, a radial load F is applied to the rolling bearing 3 between the fitting surface 1a of the shaft 1 and the fitting surface 2a of the housing 2.

As shown in FIGS. 1 to 3, the rolling bearing 3 includes an inner raceway 4 attached to the shaft 1, an outer raceway 5 attached to the housing 2, and both of these races 4, 5. It includes a plurality of rolling elements 6 interposed between them, and a retainer 7 that maintains a circumferential interval between these rolling elements 6.

The rolling bearing 3 is a deep groove ball bearing in which the rolling elements 6 are balls.

The inner bearing ring 4 is an annular bearing component having a raceway surface 4a extending in the circumferential direction on the outer circumferential side and a fitting surface 4b extending in the circumferential direction on the inner circumferential side. The raceway surface 4 a is a part of the surface of the inner raceway ring 4 that serves as a running path for the rolling elements 6 to roll and supports the radial load F applied to the rolling bearing 3 . The raceway surface 4a is called a rolling element 6 and can be contacted at a contact angle of 0° over the entire circumference in the circumferential direction. The fitting surface 4b is formed into a cylindrical surface concentric with the fitting surface 1a of the shaft 1. The width (axial length) of the fitting surface 4b is constant throughout the circumferential direction.

The fit between the fitting surface 4b of the inner bearing ring 4 and the fitting surface 1a of the shaft 1 is set to be a close fit with an interference margin. The inner bearing ring 4 is fixed to rotate integrally with the shaft 1 by an interference fit.

The outer bearing ring 5 is an annular bearing component having a raceway surface 5a extending in the circumferential direction on the inner circumferential side and a fitting surface 5b extending in the circumferential direction on the outer circumferential side. The raceway surface 5a is a portion of the surface of the outer raceway ring 5 that serves as a running path for the rolling elements 6 to roll and supports the radial load F applied to the rolling bearing 3. The raceway surface 5a is called a rolling element 6 and can be contacted at a contact angle of 0° around the entire circumference.

The outer bearing ring 5 is loosely fitted with the housing 2 as a mating member, which is either one of the shaft 1 and the housing 2.

The fitting surface 5b of the outer bearing ring 5 is formed in a curved shape along an imaginary circle concentric with the fitting surface 4b of the inner bearing ring 4 and the fitting surface 2a of the housing 2. The mating surface 5b defines the outer diameter of the outer raceway 5. The diameter of the fitting surface 5b is smaller than the diameter of the fitting surface 2a of the housing 2. The fitting surface 5b of the outer bearing ring 5 and the fitting surface 2a of the housing 2 are brought into contact by the radial load F applied to the rolling bearing 3 from the shaft 1.

The outer bearing ring 5 has a groove 5c extending in the circumferential direction on its outer circumferential side. The groove portion 5c is formed to have a finite length in the circumferential direction at a position directly below the raceway surface 5a in the radial direction.

The outer bearing ring 5 has a groove 5c only at one location in the circumferential direction. Therefore, the fitting surface 5b is continuous in the circumferential direction with a constant width in the circumferential region without the groove 5c, and is divided into two equal parts in the axial direction by the groove 5c in the circumferential region where the groove 5c is present. .

The groove portion 5c has a radial depth δ from the fitting surface 5b. The groove bottom surface of the groove portion 5c has an arcuate shape along the axial direction and the circumferential direction. The radial depth δ of the groove 5c with respect to the fitting surface 5b is substantially constant over the entire length of the groove 5c.

The length of the groove portion 5c in the circumferential direction can be defined by the angle α around the rotation center line of the shaft 1. When the rolling element pitch around the rotational center line of the shaft 1 is θ, the angle α corresponding to the circumferential length of the groove portion 5c can be set to 0<α≦2θ. Here, the rolling element pitch θ is an angle that defines the circumferential interval between the rolling elements 6 adjacent to each other in the circumferential direction, and is determined by the interval at which the cage 7 arranges the rolling elements 6 evenly in the circumferential direction. .

In the illustrated example, in order to suppress the deflection and stress of the bearing ring 5 due to the radial load F, the angle α corresponding to the circumferential length of the groove portion 5c is set within the range of 0.5θ≦α≦θ. has been done.

As shown in FIGS. 1 and 4, the position of the width center that bisects the width W ₁ of the groove portion 5c in the axial direction is from the position of the width center that bisects the width W ₂ of the raceway surface 5a in the axial direction. Located directly below in the radial direction. The width _W1 of the groove portion 5c is set to be less than or equal to the width _W2 of the raceway surface 5a. This is to ensure the width of the fitting surfaces 5b on both sides of the groove 5c and to suppress excessive deformation due to the radial load F at the groove bottom of the groove 5c and the fitting surfaces 5b on both sides of the groove 5c.

Furthermore, when considering the long axis La of the contact ellipse between the raceway surface 5a and the rolling elements 6 when the maximum radial load F is applied within the range of the radial load F applied to the rolling bearing 3, the width W of the groove portion 5c ₁ is set to be greater than or equal to the major axis La of the contact ellipse. This is to ensure that the region on which the aforementioned radial load F acts is sufficiently located on the bottom surface of the groove portion 5c.

Here, the maximum radial load F is the largest radial load F within the variation range of the radial load F applied to the rolling bearing 3 during operation of this bearing device. In addition, the major axis La of the contact ellipse is analytically determined based on Hertz's elastic contact theory, and actually measured as a contact mark caused by slight plastic deformation on the raceway surface 5a due to the radial load F from the rolling elements 6. It is determined as the width of the axial region where . In addition, in FIG. 4, in order to show the major axis La of the contact ellipse, the contact ellipse on the raceway surface 5a is projected onto the paper surface and schematically drawn.

As shown in FIG. 2, when the minimum wall thickness in the radial direction between the raceway surface 5a and the fitting surface 5b of the outer raceway ring 5 is the outer ring wall thickness H, the radial depth δ of the groove portion 5c is: It can be set to 0.005H≦δ≦0.1H. In order to suppress the deflection and stress of the outer bearing ring 5 due to the radial load F, the maximum radial depth δ of the groove portion 5c is preferably set to 0.01H≦δ≦0.05H.

Since the groove portion 5c may be formed on the outer periphery of the bearing ring 5, it can be easily formed by end milling or electric discharge machining on the outer periphery of the bearing ring 5. Here, end mill processing refers to processing using an end mill among milling tools that has cutting edges on one end surface and the outer peripheral surface of the tool. Further, electrical discharge machining refers to machining in which a part of the surface of a workpiece is removed by arc discharge repeated at short intervals between an electrode and the workpiece.

When the rolling bearing 3 is assembled between the shaft 1 and the housing 2, as shown in FIGS. A directional gap g is created.

The load area of the rolling bearing 3 that receives the radial load F extends approximately half the circumference of the rolling bearing 3. The circumferential center of the load area corresponds to the load direction of the radial load F (corresponds to the position on the extension of the radial load F in the arrow direction in FIG. 1). The outer raceway ring 5 receives a radial load F on its raceway surface 5a via the rolling elements 6 in its load bearing area, so that it undergoes elastic deformation. At this time, in the load area of the rolling bearing 3, the fitting surface 5b and groove portion 5c (particularly the portion immediately below the raceway surface 5a) of the outer raceway ring 5 are deformed in a wave-like manner. The radial height of the wave is maximum at the circumferential center of the load area, and becomes smaller as the distance from the circumferential center increases.

The radial depth δ of the groove portion 5c is set to be larger than the maximum radial height of the waveform described above in the load range of the rolling bearing 3 when the maximum radial load F is applied. Note that the radial gap g and the radial depth δ are illustrated with their sizes exaggerated. In the wave-like deformation of the raceway ring 5 that actually occurs, the relative height of the wave-like shape with respect to the fitting surface 5b is generally on the order of several μm at most.

By setting the radial depth δ, the angle α corresponding to the circumferential length, and the width _W1 described above, the groove 5c forms a groove in the load range when the maximum radial load F is applied to the rolling bearing 3. It is formed so that a radial gap g can be left between the bottom surface of the groove 5c and the fitting surface 2a of the housing 2.

During operation of this bearing device, in the load area of the rolling bearing 3 when the maximum radial load F is applied to the rolling bearing 3 between the shaft 1 and the housing 2, the outer raceway 5 is It is supported in the radial direction at the contact portion between the fitting surface 5b and the fitting surface 2a of the housing 2 in the load bearing area. At this time, even if the outer circumferential portion of the outer bearing ring 5 located in the load area deforms into a wave shape, the groove bottom surface of the groove portion 5c cannot contact the fitting surface 2a of the housing 2, and the fitting surface 5b Although a traveling wave due to a slight wave-like deformation may be transmitted to the fitting surface 2a, the reaction force from the fitting surface 2a undergoing the slight wave-like deformation does not become a force sufficient to cause the raceway ring 5 to creep.

This bearing device shown in FIGS. 1 to 4 is as described above, and when the direction of the radial load F applied to the rolling bearing 3 and the position of the groove portion 5c match as shown in FIG. The groove portion 5c suppresses the wave-like deformation of the bearing ring 5 caused by F from being transmitted as a traveling wave to the housing 2 side, which is a mating member, and thereby the creep of the bearing ring 5 can be suppressed. Furthermore, even if the direction of the radial load F does not match the position of the groove 5c due to a fluctuating load from the shaft 1 or incorrect assembly, if the bearing ring 5 creeps (one revolution at most), the direction of the radial load F will eventually Since the positions of the groove portions 5c and the groove portions 5c coincide with each other, creep can be suppressed.

Further, in this bearing device, since the groove portion 5c is formed to have a finite length in the circumferential direction, a decrease in the strength of the raceway ring 5 can be suppressed compared to a case where the groove portion is formed all around the circumference.

In this way, in this bearing device, when the bearing ring 5 of the rolling bearing 3 is loosely fitted into the housing 2, which is a mating member, the direction of the radial load F applied to the rolling bearing 3 does not match the position of the groove 5c. Even in such a case, the groove portion 5c of the bearing ring 5 can suppress creep while suppressing a decrease in the strength of the bearing ring 5.

In particular, this bearing device has a diameter between the groove portion 5c and the housing 2, which is a mating member, in the load range when the maximum radial load F is applied within the range of the radial load F applied to the rolling bearing 3. Since it is formed to leave a directional gap g, the wave-like deformation of the groove bottom surface of the groove portion 5c does not come into contact with the fitting surface 2a of the mating member, and wear of the groove bottom surface does not occur, and the raceway surface 5a and the groove portion 5c It is possible to avoid a decrease in wall thickness between the two.

Further, in this bearing device, the rolling elements 6 are made of balls, the center of the width _W1 of the groove portion 5c is located directly below the center of the width _W2 of the raceway surface 5a in the radial direction, and the width _W1 of the groove portion 5c is The width W of the raceway surface 5a is ₂ or less, and the major axis La of the contact ellipse between the raceway surface 5a and the rolling elements 6 when the maximum radial load F is applied within the range of the radial load F applied to the rolling bearing 3. Since the above settings are made, wave-like deformation due to the radial load F is caused on the groove bottom surface of the groove portion 5c, and the fitting area between the fitting surface 5b portion of the raceway ring 5 on both sides of the groove portion 5c and the mating member (housing 2) While avoiding excessive wave-like deformation of the bearing ring 5 under the radial load F, creep can be suppressed by the groove portion 5c.

Further, in this bearing device, when the minimum thickness of the bearing ring in the radial direction between the raceway surface 5a and the fitting surface 5b of the bearing ring 5 is H, and the maximum radial depth of the groove portion is δ, 0 Since it is set to .005H≦δ≦0.1H, it is possible to form a shape in which deflection and stress near the groove portion 5c of the bearing ring 5 due to the radial load F are suppressed.

Further, in this bearing device, the groove portion 5c is formed only at one location in the circumferential direction of the bearing ring 5, and the angle that defines the length of the groove portion 5c in the circumferential direction is α, and the angle that defines the pitch of the rolling elements is α. Since θ is set to 0.5θ≦α≦θ, it is possible to particularly suppress a decrease in the strength of the raceway ring 5 while effectively suppressing creep by the groove portions 5c.

In addition, in this bearing device, since the bearing ring 5 and the mating member that is loosely fitted are the housing 2, it is only necessary to form a groove on the outer circumference of the bearing ring 5, and an undercut groove is machined on the inner circumference of the housing 2. It becomes unnecessary and the manufacturing of the housing does not become difficult. For example, when housing 2 is formed as part of a transmission case, housing 2 is molded with a mold. When a groove is formed on the inner circumference of the housing 2, the groove becomes an undercut, making it difficult to manufacture the housing. However, in the case of this bearing device, creep can be suppressed by a simple device on the bearing ring 5 side. , manufacturing of the housing 2 does not become difficult.

In this bearing device, the groove portion 5c is formed only in the outer raceway ring 5, but the shape and arrangement of the groove portion are determined by the load conditions of the bearing device, the directionality of the radial load, the magnitude of the maximum radial load F, and the load load. It may be appropriately determined in consideration of the rotational force applied to the bearing ring due to contact between the fitting surface of the bearing ring and the fitting surface of the mating member in the area. For example, when the shaft and the inner raceway are fitted with a clearance, a groove may be formed on the inner periphery of the inner raceway.

Further, in this bearing device, the radial depth δ of the groove portion 5c is constant over substantially the entire length of the groove portion 5c, but the radial depth of the groove portion does not need to be constant. For example, when increasing the circumferential length of the groove, in order to prevent excessive deformation of the bearing ring, the radial depth of the groove should be made smaller as the position is further circumferentially from the circumferential center of the groove. It may be made into a shape.

Further, although a ball bearing is illustrated in this bearing device, the present invention can also be applied to a roller bearing.

The embodiments 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 rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

1 Shaft 2 Housing (mating member)
2a Fitting surface 3 Rolling bearing 5 Outer bearing ring (bearing ring)
5a Raceway surface 5b Fitting surface 5c Groove portion 6 Rolling element

Claims (5)

A shaft, a housing surrounding the shaft, and a rolling bearing interposed between the shaft and the housing, wherein the rolling bearing has a plurality of rolling elements, and one of the shaft and the housing. The bearing ring has a bearing ring that is loosely fitted to a certain mating member, the bearing ring has a raceway surface that serves as a running path for the rolling elements, and the bearing ring and the mating member have a fitting surface that extends in a circumferential direction. In a bearing device having
The raceway ring has a groove portion extending in the circumferential direction from the fitting surface with a radial depth at a position directly below the raceway surface, and the groove portion is formed to have a finite length in the circumferential direction. has been
The groove portion is formed only at one location in the circumferential direction of the bearing ring, and
When the angle that defines the length is α and the angle that defines the rolling element pitch is θ, 0.5θ≦
A bearing device characterized in that α≦θ . The groove portion is formed so as to leave a radial gap with the mating member in a load range when a maximum radial load is applied within a range of radial loads applied to the rolling bearing. The bearing device according to item 1. The rolling element is made of balls,
The width center of the groove portion is located directly below the width center of the raceway surface in the radial direction, the width of the groove portion is less than or equal to the width of the raceway surface, and the range of the radial load applied to the rolling bearing. The bearing device according to claim 1 or 2, wherein the bearing device is set to be larger than or equal to the major axis of a contact ellipse between the raceway surface and the rolling element when a maximum radial load is applied thereto. When the minimum raceway ring thickness in the radial direction between the raceway surface and the fitting surface of the raceway ring is H, and the radial depth of the groove portion is δ, set to 0.005H≦δ≦0.1H. The bearing device according to any one of claims 1 to 3, wherein: The bearing device according to any one of claims 1 to 4 , wherein the mating member comprises a housing.

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