JP2023154900A - Wheel rolling bearing device - Google Patents

Abstract

To provide a wheel rolling bearing device for, if a flange part to which a wheel is mounted is elastically deformed, preventing a cylindrical part supporting the wheel from its inner periphery side from being easily influenced thereby while enhancing accuracy of concentricity between the wheel to be mounted to the flange part and a shaft part of a joint.SOLUTION: An inward member 11 of a wheel rolling bearing device 10 having a wheel-mounted flange part 26 is provided with a through-hole 27 passing therethrough in an axial direction. A joint 50 having a cup part 51 contacting the inward member 12 and a shaft part 52 passing through the through-hole 27, and the inward member 12 are integrally rotatable. A fastening member 30 has a female screw part 31 to be threaded to a male screw part 56 provided on one axial side of the shaft part 52. The fastening member 30 has a contact face 32 for contacting the inward member 12 from one axial direction with the female screw part 31 threaded to the male screw part 56, and a cylindrical face 33 having a cylindrical outer peripheral face 34 protruded to one axial side further than the flange part 26 and coaxial with a center line L of the female screw part 31.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rolling bearing device for wheels.

As disclosed in Patent Document 1, in order to transmit the rotational power of the drive shaft to the wheel rolling bearing device 90 (see FIG. 3), the drive shaft has a hollow shaft portion (an inner member) that the rolling bearing device 90 has. ) 91 (hereinafter referred to as "joint 96"). FIG. 3 shows a portion of the fitting 96.
The hollow shaft portion 91 has a flange portion 94 on one axial side (vehicle outer side) to which a wheel 99 and a disc rotor (not shown) of a brake device are attached.

The joint 96 includes a cup portion 97 that contacts the inner ring 92 of the hollow shaft portion 91 from the other axial side (vehicle inner side), and a shaft portion 98 that passes through the through hole 91a of the hollow shaft portion 91. A male threaded portion 98a is provided at one end of the shaft portion 98 in the axial direction. By screwing and tightening the nut 95 onto the male threaded portion 98a, the joint 96 and the hollow shaft portion 91 become integrated.

Patent Document 2 discloses a wheel rolling bearing device including a pilot ring. The pilot ring has a portion that projects in the axial direction from a flange portion of the hub ring (inner member). When attaching the wheel to the flange portion, the pilot ring has the function of supporting the wheel from its inner peripheral side. A fixing nut is used to integrate the hub ring and the joint, and the fixing nut is screwed into a male threaded portion of the shaft of the joint. A pilot ring is interposed between the fixing nut and the hub ring, and the fixing nut is tightened onto the male threaded portion. As a result, the hub ring and the joint are integrated, and the pilot ring is fixed to the hub ring.

Japanese Patent Application Publication No. 2002-70880 Japanese Patent Application Publication No. 2008-68682

In the case of the wheel rolling bearing device disclosed in Patent Document 1, as shown in FIG. 3, the hollow shaft portion 91 has a cylindrical portion 93 that protrudes from a flange portion 94 to one side in the axial direction. When attaching the wheel 99 to the flange portion 94, the cylindrical portion 93 supports the wheel 99 from its inner peripheral side. The cylindrical portion 93 is integrally formed with the main body 91b of the hollow shaft portion 91 and the flange portion 94 by forging or the like. Therefore, when the flange portion 94 is elastically deformed by a force input from the wheel 99 side while the vehicle is running, stress concentration occurs at the base portion 93a of the cylindrical portion 93.

In the case of the wheel rolling bearing device disclosed in Patent Document 2, the pilot ring is provided as a separate member from the hub ring, and is positioned by fitting into the hub ring. The pilot ring is provided with a hole that passes through the shaft of the joint. The diameter of the hole is larger than that of the shaft. For this reason, the pilot ring is not positioned radially in relation to the shaft of the joint.
It is desirable that the accuracy of the coaxiality between the shaft portion of the joint, which serves as a reference for the center of rotation of the wheel and the rolling bearing device for the wheel, and the pilot ring is as high as possible. In the configuration of Patent Document 2, as described above, the pilot ring is not positioned in the radial direction in relation to the shaft portion of the joint. Therefore, there is a possibility that sufficient coaxiality accuracy cannot be obtained.

Therefore, in the present disclosure, in a rolling bearing device for a wheel, even if the flange portion to which the wheel is attached is elastically deformed, the cylindrical portion that supports the wheel from the inner circumferential side is not easily affected by the elastic deformation, and the cylindrical portion is attached to the flange portion. It is an object of the present invention to make it possible to improve the accuracy of coaxiality between a wheel and a shaft portion of a joint.

(1) The wheel rolling bearing device of the present disclosure includes an outer member having an outer raceway surface on the inner periphery, an inner member having an inner raceway surface on the outer periphery, and a space between the outer raceway surface and the inner raceway surface. a plurality of rolling elements provided in the
The inner member has a flange portion for mounting a wheel on one side in the axial direction, and is provided with a through hole passing through in the axial direction,
A rolling bearing device for a wheel in which a joint having a cup portion that contacts the inner member from the other side in the axial direction and a shaft portion that penetrates the through hole and the inner member can rotate together,
comprising a fastening member having a female threaded portion that screws into a male threaded portion provided on one side in the axial direction of the shaft portion;
The fastening member has a contact surface that contacts the inner member from one side in the axial direction by screwing the female threaded portion with the male threaded portion, and a center of the female threaded portion that protrudes from the flange portion to one side in the axial direction. and a cylindrical portion having a cylindrical outer peripheral surface coaxial with the line.

According to the wheel rolling bearing device of the present disclosure, the female threaded portion of the fastening member is screwed into the male threaded portion of the joint, thereby integrating the joint and the inner member. The fastening member is separate from the inner member, and has a cylindrical portion that protrudes to one side in the axial direction from the flange portion. Since the fastening member having the cylindrical portion is separate from the inner member, even if the flange portion is elastically deformed, the cylindrical portion is hardly affected by the elastic deformation.

The cylindrical portion has a function of supporting the wheel attached to the flange portion from its inner peripheral side. The cylindrical outer circumferential surface of the cylindrical portion is coaxial with the center line of the female threaded portion. Therefore, when the female threaded portion is screwed into the male threaded portion of the shaft portion, the degree of coaxiality between the cylindrical outer circumferential surface of the cylindrical portion and the shaft portion is increased. As a result, it is possible to improve the accuracy of coaxiality between the wheel supported by the cylindrical portion and attached to the flange portion and the shaft portion.

(2) Preferably, the inner member has a tapered hole on one axial side that increases in diameter toward the one axial side, and the fastening member contacts the tapered hole as the contact surface. It has a tapered outer peripheral surface. With this configuration, when the female threaded portion of the fastening member is screwed into the male threaded portion of the joint and tightened, part of the force due to the tightening becomes a radial force. In other words, the axial force generated in the shaft portion is alleviated. As a result, it is possible to reduce abnormal noise generated between the cup portion of the joint and the inner member.

(3) Preferably, the fastening member has a recess that is recessed from one axial side to the other axial side, and the internal thread portion opens at the center. With this configuration, it is possible to reduce the weight of the fastening member.

According to the rolling bearing device for a wheel of the present disclosure, even if the flange portion is elastically deformed, the cylindrical portion is hardly affected by the elastic deformation, and the accuracy of coaxiality between the wheel attached to the flange portion and the shaft portion of the joint is increased. becomes possible.

FIG. 1 is a sectional view showing an example of a rolling bearing device for a wheel according to the present invention. FIG. 2 is a sectional view showing the fastening member and its surroundings. FIG. 3 is a sectional view showing a conventional wheel rolling bearing device.

FIG. 1 is a sectional view showing an example of a rolling bearing device for a wheel according to the present invention. A wheel rolling bearing device 10 (hereinafter referred to as "bearing device 10") shown in FIG. 1 is a wheel bearing device (hub unit) used in an automobile. The bearing device 10 rotatably supports the wheels 7 and a disc rotor (not shown) of a brake device with respect to a suspension device provided on a vehicle body.

In order to transmit the rotational power of the drive shaft to the bearing device 10, the drive shaft is connected to a constant velocity universal joint 50 (hereinafter referred to as "joint 50") that is coupled to the bearing device 10 (inner member 12 to be described later). has. FIG. 1 shows a portion of a joint 50.

The bearing device 10 is provided with a cylindrical outer member 11, an inner member 12 having a portion located radially inward, and two rows between the outer member 11 and the inner member 12. It includes a plurality of balls (rolling elements) 13 and an annular cage 14 that holds the plurality of balls 13. In an unloaded state, the center line of the outer member 11 and the center line of the inner member 12 coincide. Let these center lines be the center line C of the bearing device 10. FIG. 1 is a sectional view taken along a plane including the centerline C.

Regarding the bearing device 10 of the present disclosure, each direction will be defined. The direction along the center line C of the bearing device 10 is defined as the "axial direction." This axial direction also includes a direction parallel to the center line C. In the bearing device 10, the vehicle outer side (the right side in FIG. 1) is defined as one axial side, and the opposite side, the vehicle inner side (the left side in FIG. 1), is defined as the other axial side. A direction perpendicular to the center line C is defined as a "radial direction." A direction along a circle centered on the center line C is defined as a "circumferential direction." The direction in which the inner member 12 rotates around the center line C is the "circumferential direction."

The outer member 11 has a fixed flange portion 21 on its outer periphery, which is fixed to a part of the suspension device (not shown). The outer member 11 has a first outer raceway surface 22a and a second outer raceway surface 22b on its inner periphery.

The inner member 12 has an inner shaft 16 and an inner ring 17 attached to the other axial side of the inner shaft 16. The inner shaft 16 has a shaft body 25 and a flange portion 26 to which the wheels 7 and the like are attached. The flange portion 26 is provided extending radially outward from an end portion 25a on one axial side of the shaft body 25. The inner ring 17 is fixed to a portion 25b on the other axial side of the shaft body 25 with an interference.

The inner shaft 16 has a first inner raceway surface 24a on its outer periphery. The inner ring 17 has a second inner raceway surface 24b on its outer periphery. The inner shaft 16 is provided with a through hole 27 that penetrates in the axial direction. The center line of the through hole 27 coincides with the center line C of the bearing device 10. The through hole 27 has a spline hole portion 28 that is spline-fitted with the shaft portion 52 of the joint 50, and a non-spline hole portion 29 that is not spline-fitted with the shaft portion 52.

The inner shaft 16 has a tapered hole 19 on one axial side thereof, the diameter of which increases toward the one axial side. The inner shaft 16 further has a cylindrical hole 20 continuous from one end of the tapered hole 19 in the axial direction. A mounting surface 26a of the flange portion 26 is provided from one end of the cylindrical hole 20 in the axial direction toward the outside in the radial direction. The attachment surface 26a is provided along a plane perpendicular to the center line C. The tapered hole 19 and the cylindrical hole 20 are holes centered on the center line C. The tapered hole 19 is connected to the through hole 27 on the other side in the axial direction.

The balls 13 included in the row on one side in the axial direction are provided between the first outer raceway surface 22a and the first inner raceway surface 24a, and are arranged between the first outer raceway surface 22a and the first inner raceway surface 24a. It makes contact with the surface 24a at a contact angle. The balls 13 included in the other row in the axial direction are provided between the second outer raceway surface 22b and the second inner raceway surface 24b, and are arranged between the second outer raceway surface 22b and the second inner raceway surface 24b. It makes contact with the surface 24b at a contact angle.

Rotational power (rotational torque) is transmitted to the inner member 12 from the joint 50 . The joint 50 includes a cup portion 51 and a shaft portion 52 extending from the cup portion 51 to one side in the axial direction. The shaft portion 52 passes through the through hole 27 of the inner shaft 16. The cup portion 51 has a cylindrical shape with a bottom that opens on the other side in the axial direction. The cup portion 51 has a larger diameter than the shaft portion 52. A side surface 55 on one axial side of the cup portion 51 is in surface contact with a side surface 18 on the other axial side of the inner ring 17 .

The shaft portion 52 includes a spline shaft portion 53 that is spline-fitted to the spline hole 28 of the inner shaft 16, and a non-spline shaft portion 54 that is not spline-fitted to the inner shaft 16. The non-spline shaft portion 54 and the non-spline hole portion 29 face each other in the radial direction. The boundary between the spline shaft portion 53 and the non-spline shaft portion 54 is located on the other side in the axial direction from the center of the balls 13 in the row on the other side in the axial direction. The non-spline shaft portion 54 is shorter in the axial direction than the conventional shaft portion (see FIG. 3). A male threaded portion 56 is provided on one side of the shaft portion 52 in the axial direction.

As described above, the bearing device 10 of this embodiment includes the outer member 11, the inner member 12, and the plurality of balls 13. The inner member 12 has a flange portion 26 for attaching the wheel 7 on one side in the axial direction. The inner member 12 is provided with a through hole 27 that penetrates in the axial direction. The joint 50 includes a cup portion 51 that contacts the inner member 12 from the other side in the axial direction, and a shaft portion 52 that penetrates the through hole 27. The spline fitting between the shaft portion 52 and the inner member 12 allows the joint 50 and the inner member 12 to rotate together.

The bearing device 10 includes a fastening member 30 for coupling the joint 50 and the inner member 12. FIG. 2 is a sectional view showing the fastening member 30 and its surroundings. The fastening member 30 is an annular member and functions as a nut. That is, the fastening member 30 has, on its inner periphery, a female threaded portion 31 that is screwed into the male threaded portion 56 of the shaft portion 52 . The female threaded portion 31 has a screw hole that opens at the center of the annular fastening member 30.

The fastening member 30 has a recess 35 that opens on one side in the axial direction. The recess 35 has a shape that is recessed from one axial side to the other axial side. The recessed portion 35 has a bottomed square hole-shaped portion (square hole portion 36). With this configuration, a jig (not shown) is fitted into the recess 35, and by rotating the jig, it becomes easy to rotate the fastening member 30 around the center line C. The square hole shape is, for example, a hexagonal hole shape or an octagonal hole shape.

The fastening member 30 has a contact surface 32 that contacts the inner shaft 16 from one side in the axial direction by screwing the female threaded portion 31 with the male threaded portion 56 . The fastening member 30 has a tapered outer peripheral surface 32 a as a contact surface 32 that contacts the tapered hole 19 . The tapered outer circumferential surface 32a and the screw hole of the female threaded portion 31 are coaxial with each other about a common center line L in the fastening member 30.

In the present disclosure, "coaxial" includes a case where a substantially permissible processing error occurs, or a case where an allowable deviation occurs due to the error.

By tightening the female threaded portion 31 to the male threaded portion 56, the contact surface 32 comes into close contact with the tapered hole 19. In this state, the center line L of the fastening member 30 coincides with the center line C of the bearing device 10. As described above (see FIG. 1), the cup portion 51 of the joint 50 contacts the inner ring 17 of the inner member 12 from the other axial side. The larger the tightening torque of the fastening member 30 with respect to the male threaded portion 56 is, the greater the force in the axial direction (axial force) is applied to the shaft portion 52 of the joint 50. As described above, the fastening member 30 functions as a nut that connects the joint 50 and the inner member 12 (inner shaft 16).

As described above (see FIG. 2), the fastening member 30 has a tapered outer peripheral surface 32a as the contact surface 32. Therefore, when the fastening member 30 is fastened to the male threaded portion 56, the axial force is applied to the shaft portion 52, and a part of the fastening force of the fastening member 30 becomes a force in the radial direction, and the inner member 12 (inner shaft 16). That is, when the fastening member 30 is tightened with the same torque as the conventional nut 95 (see FIG. 3), the axial force applied to the shaft portion 52 is relaxed in this embodiment compared to the conventional example. As a result, as will be explained later, it is possible to suppress the occurrence of abnormal noise that may occur between the cup portion 51 and the inner ring 17.

The state in which the fastening member 30 is tightened to the male threaded portion 56 and the joint 50 and the inner member 12 (bearing device 10) are integrated is referred to as an assembled state. In the assembled state, the fastening member 30 has a cylindrical portion 33 that protrudes from the flange portion 26 to one side in the axial direction. The cylindrical portion 33 has a cylindrical outer peripheral surface 34 that is coaxial with the center line L of the female threaded portion 31 . The cylindrical outer peripheral surface 34 has a cylindrical shape centered on the center line L. A square hole portion 36 is provided on the inner peripheral side of the cylindrical portion 33 . The concave portion 35 of the fastening member 30 has a surface 37 that decreases in diameter from the square hole portion 36 toward the other side in the axial direction, and the surface 37 connects with the screw hole of the female thread portion 31 .

In the assembled state, the end surface 57 on one axial side of the shaft portion 52 is within the range of the recess 35 . In the form shown in FIG. 2, the shaft portion 52 passes through the female threaded portion 31 on one side in the axial direction, but the end surface 57 thereof is located on the other side in the axial direction than the attachment surface 26a of the flange portion 26. In other words, the shaft portion 52 is shorter than the conventional one (see FIG. 3), contributing to weight reduction.

As described above, in the bearing device 10 of this embodiment (see FIG. 1), the joint 50 and the inner member 12 can rotate together. The cup portion 51 of the joint 50 contacts the inner ring 17 of the inner member 12 from the other side in the axial direction. A male threaded portion 56 is provided on one axial side of the shaft portion 52 of the joint 50 . The bearing device 10 includes a fastening member 30 , and the fastening member 30 has a female threaded portion 31 that is screwed into the male threaded portion 56 . The fastening member 30 has a contact surface 32 that contacts the inner shaft 16 of the inner member 12 from one side in the axial direction by screwing the female threaded portion 31 with the male threaded portion 56 .

The fastening member 30 has a cylindrical portion 33 that protrudes from the flange portion 26 to one side in the axial direction. The cylindrical portion 33 has a cylindrical outer peripheral surface 34 that is coaxial with the center line L of the female threaded portion 31 . By screwing the female threaded portion 31 of the fastening member 30 into the male threaded portion 56 of the joint 50, the joint 50 and the inner member 12 become integrated.

Here, a case will be described in which the bearing device 10 is attached to the body of an automobile. While the vehicle is running, various loads are applied to the bearing device 10 from, for example, the wheels 7 through the flange portions 26 . As a result, the flange portion 26 is elastically deformed so as to be inclined with respect to the center line C, for example. In this embodiment, since the fastening member 30 having the cylindrical portion 33 is a separate body (separate member) from the inner member 12 having the flange portion 26, even if the flange portion 26 is elastically deformed, the influence of the elastic deformation is suppressed by the cylindrical portion. Part 33 is difficult to accept. Conventionally (see FIG. 3), since the flange portion 94 and the cylindrical portion 93 are made of the same material, when the flange portion 94 is elastically deformed, the cylindrical portion 93 is affected by the elastic deformation, and the base portion 93a of the cylindrical portion 93 is deformed. Stress concentration occurs. In contrast, in this embodiment (see FIG. 1), it is possible to prevent such stress concentration from occurring.

When attaching the wheel 7 to the flange portion 26, the cylindrical portion 33 has a function of supporting the wheel 7 from its inner peripheral side. The cylindrical outer circumferential surface 34 of the cylindrical portion 33 is coaxial with the center line L of the female threaded portion 31 . Therefore, when the female threaded portion 31 is screwed into the male threaded portion 56 of the shaft portion 52, the coaxiality between the cylindrical outer peripheral surface 34 of the cylindrical portion 33 and the shaft portion 52 becomes high. As a result, it is possible to improve the accuracy of coaxiality between the wheel 7 supported by the cylindrical portion 33 and attached to the flange portion 26 and the shaft portion 52. Since the center line of the shaft portion 52 becomes the rotation center line of the bearing device 10, the rotation accuracy of the wheel 7 is improved.

The fastening member 30 has a recess 35 that is recessed from one axial side to the other axial side. The female threaded portion 31 is open at the center of the recessed portion 35 . The recess 35 allows the fastening member 30 to be made lighter. Further, as described above, the shaft portion 52 of the joint 50 is also shortened, and the unit of the joint 50 and the bearing device 10 is reduced in weight.

The cylindrical portion 33 located on the outer side of the vehicle is a portion that is visible from the outside of the vehicle, and is therefore coated with anti-rust coating. Conventionally (see FIG. 3), the cylindrical portion 93 is coated with anti-rust coating, but the flange portion 94 is not coated, so masking is required.
In contrast, in this embodiment, the fastening member 30 having the cylindrical portion 33 is a separate member from the inner member 12 having the flange portion 26. Since the fastening member 30 can be individually coated with anti-rust coating, masking of the flange portion 26 can be eliminated, and the number of work steps can be reduced.

Manufacturing and assembly of each part of the bearing device 10 will be explained. Conventionally (see FIG. 3), before press-fitting and attaching the inner ring 92 to the main body 91b of the hollow shaft part 91, the outer circumferential surface of the cylindrical part 93 is machined using a part of the main body 91b as a reference to ensure accuracy. are doing. After that, the inner ring 92 is press-fitted into the main body 91b. Then, the diameter of the main body 91b is reduced, which may affect the coaxiality between the hollow shaft portion 91 and the cylindrical portion 93.

On the other hand, in this embodiment, after the inner ring 17 is press-fitted into the inner shaft 16, the shaft portion 52 is passed through the through hole 27 of the inner shaft 16, and the fastening member 30 is used to tighten the inner ring 17. Therefore, the press-fitting of the inner ring 17 does not affect the coaxiality of the cylindrical portion 33. In the fastening member 30, if the female threaded portion 31 and the cylindrical outer peripheral surface 34 of the cylindrical portion 33 are manufactured with high precision by machining, highly accurate coaxiality can be obtained in the cylindrical outer peripheral surface 34.

The female threaded portion 31 of the fastening member 30 is formed by threading the cylindrical outer circumferential surface 34 as a reference. Therefore, the degree of coaxiality between the female threaded portion 31 and the cylindrical outer circumferential surface 34 is high. By screwing such a fastening member 30 into the male threaded portion 56 of the shaft portion 52, the accuracy of coaxiality between the cylindrical outer circumferential surface 34 and the shaft portion 42 is also increased.

In this embodiment, as described above, the inner member 12 has a tapered hole 19 on one axial side thereof, the diameter of which increases toward the one axial side. The fastening member 30 has a tapered outer circumferential surface 32 a as a contact surface 32 that contacts the tapered hole 19 . With this configuration, when the female threaded portion 31 of the fastening member 30 is screwed into the male threaded portion 56 of the joint 50 and tightened, part of the force due to the tightening becomes a radial force. That is, even if the fastening member 30 is tightened with the same tightening torque as the nut 95 of the conventional example (FIG. 3), the axial force (axial force) generated in the shaft portion 52 is relaxed (reduced).

Here, in the bearing device 10 coupled to the joint 50 shown in FIG. 1, abnormal noise may occur between the cup portion 51 and the inner ring 17 due to the mechanism described below. Note that the abnormal noise is called a stick-slip sound or a clicking sound. Conventionally, the abnormal noise may be in the audible range.

The mechanism of abnormal noise generation will be explained. The shaft portion 52 of the joint 50 and the inner member 12 are spline-fitted. Torque is transmitted between the spline shaft portion 53 and the spline hole 28, and no twisting occurs in the spline shaft portion 53. On the other hand, at least one of the boundary portion between the shaft portion 52 and the cup portion 51 and the non-spline shaft portion 54 may be twisted.

Even if such twisting occurs, since the side surface 18 of the inner ring 17 and the side surface 55 of the cup portion 51 are pressed against each other, the frictional force (static frictional force) between them will prevent the vehicle from running steadily. At this time, no slippage occurs between the inner ring 17 and the cup portion 51. However, when the vehicle is started, the torque transmitted from the joint 50 to the inner member 12 may increase rapidly. Then, a slight slip occurs between the inner ring 17 and the cup portion 51 against the frictional force, and an abnormal noise is generated accordingly.

The greater the axial force (axial force) generated on the shaft portion 52 of the joint 50, the greater the frictional force and the lower the frequency of slipping. However, as the axial force increases, the energy stored in the torsion direction in the non-spline shaft portion 54 and the like increases accordingly. Therefore, although the frequency of abnormal noises is reduced, the accumulated energy increases, and when it exceeds a certain level, the above-mentioned slipping occurs. In other words, it is considered impossible to completely suppress the slippage.

Therefore, in this embodiment, as described above, the axial force (axial force) generated in the shaft portion 52 is alleviated. In this case, the frictional force between the inner ring 17 and the cup portion 51 becomes smaller, and the frequency of minute slips between them becomes higher, but the stored energy becomes smaller and an opening sound that reaches an audible range is less likely to occur. In other words, it is possible to suppress the generation of unpleasant noises.

The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is not limited to the above-described embodiments, and includes all modifications within the scope of equivalents to the configurations described in the claims.

7 Wheels 10 Rolling bearing device for wheels 11 Outer member 12 Inner member 13 Balls (rolling elements)
19 Tapered hole 22a First outer raceway surface 22b Second outer raceway surface 24a First inner raceway surface 24b Second inner raceway surface 26 Flange portion 27 Through hole 30 Fastening member 31 Female threaded portion 32 Contact surface 32a Tapered outer peripheral surface 33 Cylindrical part 34 Cylindrical outer peripheral surface 35 Recessed part 50 Constant velocity universal joint (joint)
51 Cup part 52 Shaft part 56 Male thread part L Center line

Claims (3)

An outer member having an outer raceway surface on an inner periphery, an inner member having an inner raceway surface on an outer periphery, and rolling elements provided between the outer raceway surface and the inner raceway surface,
The inner member has a flange portion for mounting a wheel on one side in the axial direction, and is provided with a through hole passing through in the axial direction,
A rolling bearing device for a wheel in which a joint having a cup portion that contacts the inner member from the other side in the axial direction and a shaft portion that penetrates the through hole and the inner member can rotate together,
comprising a fastening member having a female threaded portion that screws into a male threaded portion provided on one side in the axial direction of the shaft portion;
The fastening member is
a contact surface that contacts the inner member from one side in the axial direction by screwing the female threaded portion with the male threaded portion;
a cylindrical portion having a cylindrical outer peripheral surface that protrudes to one side in the axial direction from the flange portion and is coaxial with the center line of the female threaded portion;
A rolling bearing device for wheels. The inner member has a tapered hole on one side in the axial direction, the diameter of which increases toward the one side in the axial direction,
The fastening member has, as the contact surface, a tapered outer peripheral surface that contacts the tapered hole.
The rolling bearing device for a wheel according to claim 1. The rolling bearing device for a wheel according to claim 1 or 2, wherein the fastening member has a concave shape recessed from one axial side to the other axial side and has a concave portion in the center of which the female thread portion opens.

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