Wheel bearing device

Abstract

The present invention provides a wheel bearing device that prevents the ring member from moving radially due to diameter expansion during crimping, and reliably receives the stress on the crimped portion caused by the internal teeth of the gear contacting the base end of the crimped portion, thereby suppressing damage to the crimped portion. [Solution] A wheel bearing device 1 comprising a gear 11 fitted to a hub ring 3 on the axial side of a pair of inner rings 4A and 4B, wherein the gear 11 has internal teeth 11a that mesh with external teeth 3f formed on the hub ring 3, a groove 11b formed by cutting out the portion including the internal teeth 11a at the other axial end of the gear 11 and extending along the circumferential direction, and an inner side end face 11c, and the hub ring 3 has a crimped portion 3d crimped to the inner side end face 11c of the gear 11, and a ring member 12 is interposed between the groove 11b of the gear 11 and the base end of the crimped portion 3d on the hub ring 3.

Description

Technical Field

[0001] The present invention relates to the technology of wheel bearing devices.

Background Art

[0002] Conventionally, as a wheel bearing device for an automobile, a double-row tapered roller bearing is generally used. The wheel bearing device includes an outer member having a double-row outer raceway surface formed on its inner circumference, a hub ring having a wheel mounting flange for mounting a wheel at one axial end, and a pair of inner rings fitted to the hub ring on the other axial side of the wheel mounting flange and having an inner raceway surface facing the double-row outer raceway surface formed on its outer circumference, and a double-row rolling elements rotatably accommodated between both raceway surfaces. Further, a gear fitted to the hub ring on the other axial side of the inner ring is provided (see, for example, Patent Document 1).

[0003] The gear has internal teeth that mesh with external teeth formed on the outer peripheral surface of the hub ring, and the external teeth and the internal teeth engage with each other so that the gear rotates integrally with the hub ring. Gear teeth are provided at the outer peripheral end of the gear so as to be able to mesh with the gear teeth of an input gear from outside (not shown). The gear transmits torque to the hub when the gear teeth mesh with the gear teeth of the input gear from outside.

[0004] In the conventional wheel bearing device, the gear is fixed axially immovable by a caulking portion provided at the axially inner side end portion of the hub ring. Further, in order to prevent the internal teeth of the gear from contacting the base end portion of the caulking portion and protect the base end portion of the caulking portion, a ring member is provided between the base end portion and the inner side end surface of the internal teeth. Since the ring member can receive the stress that the internal teeth of the gear abut against the base end portion of the caulking portion, it is possible to prevent the base end portion from being damaged by the internal teeth.

[0005] In conventional wheel bearing devices, the ring member is interposed between the internal teeth and the crimping portion. However, since there is no restraining force that fixes the ring member radially inward during the crimping process, if the crimping portion expands axially outward, the ring member may move radially outward in accordance with the expansion.

[0006] When the ring member moves radially outward due to the diameter expansion, it can ride up onto the internal teeth, causing the internal teeth to come into direct contact with the base, and the shape of the internal teeth may be transferred to the R-shaped surface of the base. Therefore, in actual use environments where a rotational load is applied, stress may concentrate on the base where the shape of the internal teeth has been transferred, potentially reducing the strength of the crimped portion. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] U.S. Patent No. 6,299,360 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Therefore, the present invention has been made in view of the above circumstances, and aims to provide a wheel bearing device that prevents the ring member from moving radially due to diameter expansion during crimping, and that can reliably receive the stress on the crimped portion caused by the internal teeth of the gear contacting the base end of the crimped portion with the ring member, thereby suppressing damage to the crimped portion. [Means for solving the problem]

[0009] Specifically, the wheel bearing device comprises an outer member having double rows of outer raceway surfaces on its inner circumference, a hub ring having a wheel mounting flange for attaching a wheel at one axial end, and an inner member consisting of a pair of inner rings fitted to the hub ring on the other axial side of the wheel mounting flange and having inner raceway surfaces facing the double rows of outer raceway surfaces, a double row of rolling elements rotatably housed between the two raceway surfaces of the outer member and the inner rings, and a gear fitted to the hub ring on the other axial side of the pair of inner rings, wherein the gear has internal teeth that mesh with external teeth formed on the hub ring, a groove formed by cutting out the inner diameter portion of the other axial end of the gear and extending along the circumferential direction, and an axial end face on the other side, the hub ring has a crimped portion crimped onto the axial end face of the gear, and a ring member is interposed between the groove of the gear and the base end of the crimped portion on the hub ring. [Effects of the Invention]

[0010] The present invention provides the following effects: In other words, according to the wheel bearing device of the present invention, during the crimping process, the ring member is fitted into the groove, which prevents the ring member from moving radially due to the expansion of its diameter. The ring member reliably receives the stress that would otherwise be exerted by the internal teeth of the gear contacting the base end of the crimped portion, thereby suppressing damage to the crimped portion. [Brief explanation of the drawing]

[0011] [Figure 1] A partial cross-sectional view showing a wheel bearing device according to an embodiment of the present invention. [Figure 2] An enlarged cross-sectional view showing the configuration of the gear, crimping section, and ring member of a wheel bearing device according to an embodiment of the present invention before crimping. [Figure 3] Figure 3(A) is an enlarged cross-sectional view showing the configuration of the gear, crimping portion, and ring member of a wheel bearing device according to an embodiment of the present invention, and Figure 3(B) is an enlarged view of the portion enclosed by the circle in Figure 3(A). [Figure 4]An enlarged cross-sectional view showing the configuration of the gear, crimping portion, and ring member of a wheel bearing device according to an embodiment of the present invention. [Figure 5] Figure 5(A) is an enlarged cross-sectional view showing the configuration of the gear, crimping portion, and ring member of a wheel bearing device according to an embodiment of the present invention, and Figure 5(B) is an enlarged view of the portion enclosed by the circle in Figure 5(A). [Figure 6] An enlarged cross-sectional view showing the configuration of the gear, crimping portion, and ring member of a wheel bearing device according to an embodiment of the present invention. [Figure 7] An enlarged cross-sectional view showing the configuration of the inner ring on the outer side of a wheel bearing device according to an embodiment of the present invention. [Modes for carrying out the invention]

[0012] The embodiments for carrying out the present invention will be described below with reference to the attached drawings.

[0013] The wheel bearing device 1 shown in Figure 1 is one embodiment of the wheel bearing device according to the present invention, and is used to rotatably support a wheel in the suspension system of a vehicle such as an automobile.

[0014] As shown in Figure 1, the wheel bearing device 1 has a configuration referred to as the 2.5th generation, and comprises an outer ring 2 which is an outer member, a hub ring 3 and a pair of inner rings 4A and 4B which are inner members, two rows of inner rolling elements 5 and outer rolling elements 6 which are rolling elements, an inner sealing member 9 and an outer sealing member 10.

[0015] Here, "inner side" refers to the side of the wheel bearing device 1 that is attached to the vehicle body, and "outer side" refers to the side of the wheel bearing device 1 that is attached to the vehicle body. Furthermore, "axial direction" refers to the direction along the rotation axis X of the wheel bearing device 1, with one axial side being the outer side and the other axial side being the inner side. The direction perpendicular to the rotation axis X of the wheel bearing device 1 is referred to as the radial direction. In the following, "cross-section" will be described as a cross-section that passes through the rotation axis X of the wheel bearing device 1 and is parallel to the rotation axis X of the wheel bearing device 1.

[0016] As shown in Fig. 1, on the inner peripheral surface of the outer ring 2, an inner outer raceway surface 2c and an outer outer raceway surface 2d are formed. On the outer peripheral surface 2e of the outer ring 2, a vehicle body mounting flange 2f for attaching the outer ring 2 to a vehicle body side member is integrally formed.

[0017] Further, on the inner side end of the outer ring 2, an inner side opening 2a into which an inner side seal member 9 can be fitted is formed. The inner side seal member 9 is fitted into the inner side opening 2a and closes the inner side opening 2a. On the outer side end of the outer ring 2, an outer side opening 2b into which an outer side seal member 10 can be fitted is formed. The outer side seal member 10 is fitted into the outer side opening 2b and closes the outer side opening 2b. By fitting the inner side seal member 9 into the inner side opening 2a which is an opening at one axial end side of the annular space formed by the outer ring 2 and the hub ring 3, and fitting the outer side seal member 10 into the outer side opening 2b which is an opening at the other axial end side of the annular space, the annular space inside the bearing is sealed. On the outer peripheral surface 2e of the outer ring 2, a vehicle body mounting flange 2f for attaching to a knuckle of a suspension device is integrally provided.

[0018] Also, on the outer peripheral surface of the hub ring 3, a small diameter step portion 3a continuous from the wheel mounting flange 3b is formed. With the large end face 4d of the outer inner ring 4B abutting against the shoulder portion 3c which is the continuous surface of the wheel mounting flange 3b and the small diameter step portion 3a, the inner ring 4B is press-fitted into the small diameter step portion 3a via a predetermined tightening washer. On the shoulder portion 3c of the hub ring 3, an abutting portion 3e against the large end face 4d of the outer inner ring 4B is provided.

[0019] Then, the inner rings 4A and 4B are fixed in a state where preload is applied by a caulking portion 3d formed by plastically deforming the inner side end portion of the small diameter step portion 3a radially outward, and have a self-retaining structure that can maintain a stable preload over a long period without adjusting the preload by adjusting the tightening torque of the nut or the like.

[0020] As shown in the figure, the clamping portion 3d is provided at the inner side end portion, and external teeth 3f for fixing the gear 11 are provided on the outer side of the clamping portion 3d.

[0021] A plurality of bolt holes 3g are formed in the wheel mounting flange 3b. A hub bolt 3h for fastening the hub ring 3 to the wheel or brake components is press-fitted into the bolt hole 3g. The wheel mounting flange 3b is an example of a hub flange extending radially outward.

[0022] The inner rings 4A and 4B are provided on the small-diameter step portion 3a of the hub ring 3. Here, the inner ring on the inner side is referred to as 4A, and the inner ring on the outer side is referred to as 4B for explanation. The inner rings 4A and 4B are press-fitted into the small-diameter step portion 3a through a predetermined interference fit. Further, the hub ring 3 and the inner rings 4A and 4B are integrated by the clamping portion 3d plastically deformed by clamping the inner side end portion of the small-diameter step portion 3a of the hub ring 3, preventing the inner rings 4A and 4B from axially coming off the hub ring 3.

[0023] The inner rings 4A and 4B apply preload to the inner rolling element row 5 and the outer rolling element row 6 which are rolling element rows. An inner inner raceway surface 4a is provided on the outer peripheral surface of the inner ring 4A on the inner side so as to face the inner outer raceway surface 2c of the outer ring 2. Also, an outer inner raceway surface 4b is provided on the outer peripheral surface of the inner ring 4B on the outer side so as to face the outer outer raceway surface 2d.

[0024] The inner rolling row 5 and the outer rolling row 6, which are rolling elements, are composed of multiple tapered rollers 7 held by a cage 8. The inner rolling row 5 is rotatably sandwiched between the inner raceway surface 4a on the inner side of the inner ring 4A and the outer raceway surface 2c on the inner side of the outer ring 2. The outer rolling row 6 is rotatably sandwiched between the inner raceway surface 4b on the outer side of the inner ring 4B and the outer raceway surface 2d on the outer side of the outer ring 2. In other words, the inner rolling row 5 and the outer rolling row 6 are rotatably housed between the raceway surfaces of the outer ring 2, which is the outer member, and the inner rings 4A and 4B, which are the inner members. The outer ring 2 rotatably supports the hub ring 3 and the inner rings 4A and 4B via the inner rolling row 5 and the outer rolling row 6.

[0025] An annular encoder 20, whose outer surface is the detection surface, is fitted between the inner rolling row 5 and the outer rolling row 6. The encoder 20 is located on the outer circumference of the pair of inner rings 4A and 4B of the inner member, and its center in the width direction is located on the adjacent surfaces of the inner rings 4A and 4B on both sides.

[0026] A magnetic sensor 21 is mounted on the outer ring 2, facing the detection surface which is the outer circumferential surface of the encoder 20. The magnetic sensor 21 detects the rotation of the inner member, i.e., the rotation of the wheel, by detecting the rotation of the encoder 20. The magnetic sensor 21 has a sensor element, such as an IC chip, built into a sensor casing made of a resin case or molded resin, with the tip surface being the detection surface. As shown in Figure 1, the magnetic sensor 21 is mounted on the outer ring 2 at a central position between the inner rolling row 5 and the outer rolling row 6, in a position inclined with respect to the rotation axis X direction.

[0027] In the wheel bearing device 1, a double-row tapered roller bearing is formed by an outer ring 2, a hub ring 3 and inner rings 4A and 4B, an inner rolling row 5, and an outer rolling row 6. The wheel bearing device 1 may also be composed of a double-row angular contact ball bearing.

[0028] Furthermore, as shown in Figure 2, a gear 11 that is fitted to the hub ring 3 is provided on the inner side of the inner ring 4A on the inner side. The gear 11 is fixed to the hub wheel 3 so as to be integrally rotatable, and is a component that transmits power to the hub wheel 3 by meshing with an external input gear (not shown). The gear 11 has internal teeth 11a that mesh with external teeth 3f formed on the hub wheel 3, a groove 11b formed by cutting out the portion including the internal teeth 11a at the inner end of the gear 11 and extending along the circumferential direction, an inner end face 11c, and external teeth 11d provided on the radially outer side.

[0029] The internal teeth 11a of the gear 11 are formed along the entire circumferential direction of the inner surface, and mesh with the external teeth 3f of the hub wheel 3 by inserting the gear 11 from the inner side to the outer side into the hub wheel 3 before the crimping portion 3d is formed. The groove portion 11b is a portion formed by cutting out the inner end of the internal teeth 11a, and does not mesh with the external teeth 3f in this portion.

[0030] As shown in Figures 3(A) and 3(B), the groove 11b has a cross-sectional shape that is arc-shaped. A ring member 12 is interposed between the groove 11b and the base end of the crimping portion 3d of the hub wheel 3. The ring member 12 is a substantially C-shaped member with a part of its circumferential direction open, and its cross-section is formed to be circular. Therefore, when the ring member 12 is interposed in the groove 11b, the outer surface of the ring member 12 and the inner surface of the groove 11b are in close contact. The ring member 12 is made of a special steel such as SCM material. However, the material of the ring member 12 is not limited to SCM material, and any material with good hardenability and toughness may be used. For example, the material of the ring member 12 may be made of case-hardened steel (carburized steel) such as SCr430.

[0031] Furthermore, as shown in Figure 4, the center position O1 of the arc shape of the groove 11b is located on the outer side of the inner end face 11c of the gear 11. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes outward from the inner end face 11c of the gear 11 can be reduced.

[0032] Furthermore, the axial distance D1 between the inner end face 11c of the gear 11 and the center position O1 of the arc shape of the groove 11b is smaller than half the diameter (radius R) of the cross-sectional shape of the ring member 12. This ensures that the volume of the ring member 12 protruding outward from the inner end face of the gear 11 is secured, and that the ring member 12 always protrudes outward from the inner end face of the gear 11.

[0033] Furthermore, the axial distance D1 between the center position O1 of the arc shape in the groove 11b and the inner end face 11c of the gear 11 is 0.3 mm to 0.6 mm. With this configuration, the radius R of the ring member 12 is set to 0.6 mm or more, and the ring member 12 can be formed into a circular cross-sectional shape with a diameter of, for example, 2 mm. This ensures that the volume of the ring member 12 protruding outward from the inner end face 11c of the gear 11 is secured, and the ring member 12 is always configured to protrude outward from the inner end face 11c of the gear 11.

[0034] Furthermore, as shown in Figure 3(B), the center position O2 of the circular cross-sectional shape of the ring member 12 is located on the outer diameter side of the inner diameter side end (shown by the dashed line) of the internal teeth 11a of the gear 11. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes toward the inner diameter side of the gear 11 can be reduced.

[0035] Furthermore, in another embodiment, as shown in Figures 5(A) and 5(B), the cross-sectional shape of the groove 11b may be configured to have a radius of curvature R1 that is greater than or equal to the radius R of the cross-sectional shape of the ring member 12. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes outward from the inner end face of the gear 11 can be reduced.

[0036] In another embodiment, as shown in Figure 6, the cross-sectional shape of the groove 11b may be rectangular. The ring member 12 has a circular cross-sectional shape, and the center of the circular cross-sectional shape is located on the outer side of the inner end face of the gear 11. By configuring it in this way, the direction in which stress is received by contact between the ring member and the two rectangular groove 11b can be limited.

[0037] The outer ring 2 and inner rings 4A and 4B are formed from high-carbon chromium steel such as SUJ2, and hardened to a core hardness of 58-64 HRC by deep quenching. However, the outer ring 2 and inner rings 4A and 4B are not limited to high-carbon chromium steel; they may also be formed from medium-carbon steel containing 0.40-0.80 wt% carbon, such as S53C (JIS standard SC-type carbon steel for machine structures), or from case-hardened steel (carburized steel), such as SCr430, and at least the outer raceway surfaces 2c and 2d of the double-row outer raceway surfaces may be hardened to a core hardness of 58-64 HRC by high-frequency induction hardening.

[0038] Furthermore, as shown in Figure 7, in this embodiment, the shoulder portion 3c of the hub ring 3 is provided with a contact portion 3e with the large end face 4d of the outer inner ring 4B, and the corner portion A between the contact portion 3e and the small diameter step portion 3a is formed by an arcuate surface, as shown in an enlarged view in Figure 7. A chamfered portion 4e is provided at the inner diameter end on the large end face 4d side of the outer inner ring 4B.

[0039] Furthermore, as shown in Figure 3, a chamfered portion 4f is provided on the inner diameter end of the large end face 4d side of the inner ring 4A. The chamfered volume of the chamfered portion 4f is smaller than the chamfered volume of the chamfered portion 4e. By configuring it in this way, the chamfered portion 4f of the large end face 4d of the inner ring 4A is set to be smaller than the chamfered portion 4e of the large end face 4d of the outer ring 4B. This suppresses deformation of the inner ring 4A during crimping and improves durability, while also suppressing stress generated at the corner A of the shoulder portion 3c and the small diameter step portion, thereby increasing the strength of the hub ring 3 and improving durability.

[0040] Furthermore, the chamfered portion 4f of the inner ring 4A has an arcuate surface with a radius of curvature in the range of 1.0 to 2.5 mm. This configuration suppresses the elastic deformation of the outer diameter of the inner ring 4A caused by the crimping load, thereby reducing the hoop stress generated in the outer diameter, and also prevents damage such as minute cracks from occurring in the crimped portion 3d.

[0041] As shown in Figures 2 and 3, the inner rings 4A and 4B are inserted into the small-diameter stepped portion 3a of the hub ring 3 before crimping, and then the gear 11 is inserted. The internal teeth 11a of the gear 11 mesh with the external teeth 3f formed on the outer diameter surface of the hub ring 3. A ring member 12 is interposed in the groove portion 11b of the internal teeth 11a of the gear 11. The center position O2 of the ring member 12 is positioned inside the inner end face 11c of the gear 11. This reduces the volume of the ring member 12 that protrudes outward from the inner end face 11c of the gear 11.

[0042] As shown in Figure 3, a crimped portion 3d is formed by a crimping process. During the formation of the crimped portion 3d, the ring member 12 is subjected to a force that moves it radially outward, but radial movement of the ring member 12 is prevented by contact with the groove portion 11b. This prevents the ring member 12 from riding up onto the internal teeth 11a and transferring the shape of the internal teeth 11a onto the ring member.

[0043] The ring member 12 is interposed in the groove 11b, which prevents transfer due to contact of the internal teeth 11a with the base of the crimping portion 3d, and further prevents stress concentration at the base of the crimping portion 3d.

[0044] As described above, the wheel bearing device 1 according to the present invention comprises an outer ring 2 having double rows of outer raceway surfaces 2c and 2d on its inner circumference, a hub ring 3 having a wheel mounting flange 3b at one axial end for mounting a wheel, and an inner member consisting of a pair of inner rings 4A and 4B fitted to the hub ring 3 on the other axial side of the wheel mounting flange 3b and having inner raceway surfaces 4a and 4b facing the double rows of outer raceway surfaces 2c and 2d, and a double row of tapered rollers 7 rotatably housed between the outer raceway surfaces 2c and 2d and the inner raceway surfaces 4a and 4b of the outer ring 2 and the inner rings 4A and 4B, and a pair of inner rings 4A and 4 A wheel bearing device 1 comprises a gear 11 fitted to a hub wheel 3 on the axial side opposite to B, wherein the gear 11 has internal teeth 11a that mesh with external teeth 3f formed on the hub wheel 3, a groove 11b formed by cutting out the portion including the internal teeth 11a at the other axial end of the gear 11 and extending along the circumferential direction, and an inner side end face 11c, and the hub wheel 3 has a crimped portion 3d crimped to the inner side end face 11c of the gear 11, and a ring member 12 is interposed between the groove 11b of the gear 11 and the base end of the crimped portion 3d on the hub wheel 3. With this configuration, during the formation of the crimped portion 3d, the ring member 12 is subjected to a force that moves it radially outward, but its radial movement is prevented by contact with the groove portion 11b. This prevents the ring member 12 from riding up onto the internal teeth 11a and transferring the shape of the internal teeth 11a. Furthermore, during the crimping process, the ring member 12 reliably receives the stress that would otherwise be exerted by the internal teeth 11a of the gear 11 contacting the base end of the crimped portion 3d, thereby suppressing damage to the crimped portion 3d.

[0045] Furthermore, the groove portion 11b has a cross-sectional shape that is arc-shaped, and the center position O1 of the arc shape is located on the outer side of the inner end face 11c of the gear 11. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes outward from the inner end face 11c of the gear 11 can be reduced.

[0046] Furthermore, the ring member 12 has a circular cross-sectional shape, and the axial distance D1 between the inner end face 11c of the gear 11 and the center position O1 of the arc shape is less than half the diameter of the cross-sectional shape of the ring member 12. By configuring it in this way, the volume of the ring member 12 that protrudes outward from the inner end face 11c of the gear 11 can be secured, ensuring that the ring member 12 always protrudes outward from the inner end face of the gear 11.

[0047] Furthermore, the axial distance D1 between the center position O1 of the arc shape in the groove 11b and the inner end face 11c of the gear 11 is 0.3 mm to 0.6 mm. By configuring it in this way, the radius of the ring member 12 is set to 0.6 mm or more, ensuring that the volume of the ring member 12 protruding outward from the inner end face 11c of the gear 11 is secured, and that the ring member 12 always protrudes outward from the inner end face 11c of the gear 11.

[0048] Furthermore, the ring member 12 has a circular cross-sectional shape, and the cross-sectional shape of the groove portion 11b has a radius of curvature R1 that is greater than or equal to the radius of curvature R of the cross-sectional shape of the ring member 12. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes outward from the inner end face 11c of the gear 11 can be reduced.

[0049] The groove 11b has a rectangular cross-sectional shape, and the ring member 12 has a circular cross-sectional shape, with the center of the circular cross-sectional shape located on the outer side of the inner end face 11c of the gear 11. This configuration limits the direction in which stress is received by the contact between the ring member 12 and the two surfaces of the rectangular groove 11b. Furthermore, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes outward beyond the inner end face 11c of the gear 11 can be reduced.

[0050] The center position O2 of the circular cross-sectional shape of the ring member 12 is located on the outer diameter side of the inner diameter side end of the internal teeth 11a of the gear 11. By configuring it in this way, when the ring member 12 is interposed in the groove 11b, the volume of the ring member 12 that protrudes toward the inner diameter side of the gear 11 can be reduced.

[0051] Furthermore, abutment portion 3e is formed on the hub ring 3 with the large end face 4d of the outer inner ring 4B of the pair of inner rings 4A and 4B, a chamfered portion 4e is formed on the inner diameter end on the large end face 4d side of the outer inner ring 4B of the pair of inner rings 4A and 4B, and a chamfered portion 4f is formed on the inner diameter end of the large end face 4d of the inner inner ring 4A of the pair of inner rings 4A and 4B, and the chamfered portion 4f of the large end face 4d of the inner inner ring 4A is set to be smaller than the chamfered portion 4e of the large end face 4d of the outer inner ring 4B. By configuring it in this way, the chamfered portion 4f of the large end face 4d of the inner ring 4A is set to be smaller than the chamfered portion 4e of the large end face 4d of the outer ring 4B. This suppresses deformation of the inner ring 4A during crimping, improving durability, and also suppresses stress generated at the shoulder portion 3c and the corner portion A of the small diameter step, thereby increasing the strength of the hub ring 3 and improving durability.

[0052] Furthermore, the chamfered portion 4f of the inner ring 4A on the inner side has an arcuate surface with a radius of curvature in the range of 1.0 to 2.5 mm. By configuring it in this way, the elastic deformation of the outer diameter of the inner ring 4A caused by the crimping load is suppressed, reducing the hoop stress generated in the outer diameter, and preventing damage such as minute cracks from occurring in the crimped portion 3d.

[0053] Although embodiments of the present invention have been described above, the present invention is not limited in any way to these embodiments, but is merely illustrative. It can be implemented in various other forms without departing from the spirit of the invention, and the scope of the present invention is indicated by the claims, and further includes all modifications within the meaning and scope of equivalents as described in the claims. [Explanation of symbols]

[0054] 1. Wheel bearing device 2. Outer ring (outer member) 2a Inner side opening 2b Outer side opening 2c Outer raceway surface 2d outer raceway 2e Outer surface 2f Body mounting flange 3. Hub ring (inner member) 3a Small diameter stepped section 3b Wheel mounting flange 3c Shoulder 3D crimping section 3e Butt section 3f external teeth 3g bolt hole 3h hub bolts 4A / 4B Inner ring (inner component) 4a Inner raceway surface 4b Inner raceway surface 4d big end face 4e Chamfered section (outer side) 4f Chamfered section (inner side) 5. Inner side rolling row 6. Outer rolling train 7 Cone roller (rolling element) 8 Cage 9. Inner side sealing member 10 Outer side sealing member 11 gears 11a Internal teeth 11b Groove 11c Inner side end face (other end face on the axial side) 11d external teeth 12 Ring member

Claims

1. An outer member having double rows of outer raceway surfaces on its inner circumference, An inner member comprising a hub wheel having a wheel mounting flange for attaching a wheel at one axial end, and a pair of inner rings fitted to the hub wheel on the other axial side of the wheel mounting flange and having double rows of inner raceway surfaces facing the outer raceway surfaces, A double row of rolling elements is housed so as to be able to roll between the raceway surfaces of the outer member and the inner ring, A gear fitted to the hub ring on the axial side opposite to the pair of inner rings, A wheel bearing device comprising, The gear has internal teeth that mesh with external teeth formed on the hub ring, a groove formed by cutting out the inner diameter portion of the other axial end of the gear and extending along the circumferential direction, and an end face on the other axial side. The hub wheel has a crimped portion crimped onto the other axial end face of the gear, A wheel bearing device in which a ring member is interposed between the groove portion of the gear and the base end of the crimped portion of the hub ring.

2. The groove portion has a cross-sectional shape that is arc-shaped, The wheel bearing device according to claim 1, wherein the center position of the arc shape is located axially on one side of the other axial end face of the gear.

3. The ring member has a circular cross-sectional shape, The wheel bearing device according to claim 2, wherein the axial distance between the other end face of the gear in the axial direction and the center position of the arc shape is less than half the diameter of the cross-sectional shape of the ring member.

4. The wheel bearing device according to claim 3, wherein the axial distance between the center position of the arc shape in the groove and the other end face of the gear in the axial direction is 0.3 mm to 0.6 mm.

5. The ring member has a circular cross-sectional shape, The wheel bearing device according to any one of claims 1 to 4, wherein the cross-sectional shape of the groove portion is an arc shape having a radius of curvature greater than or equal to the radius of curvature of the cross-sectional shape of the ring member.

6. The groove portion has a rectangular cross-sectional shape, The wheel bearing device according to claim 1, wherein the ring member has a circular cross-sectional shape, and the center of the circular cross-sectional shape is located on one axial side of the other axial end face of the gear.

7. The center position of the circular cross-sectional shape of the ring member is, The wheel bearing device according to claim 6, wherein the bearing is positioned on the outer diameter side of the inner diameter end of the internal teeth in the gear.

8. The wheel bearing device according to claim 1, wherein the hub ring has abutment portion formed with the large end face of the axially-side inner ring of the pair of inner rings, a chamfered portion is formed on the inner diameter end on the large end face side of the axially-side inner ring of the pair of inner rings, a chamfered portion is formed on the inner diameter end of the large end face of the other axially-side inner ring of the pair of inner rings, and the chamfered portion on the large end face of the other axially-side inner ring is set to be smaller than the chamfered portion on the large end face of the axially-side inner ring.

9. The wheel bearing device according to claim 8, wherein the chamfered portion of the inner ring on the other axial side is an arcuate surface having a radius of curvature in the range of 1.0 to 2.5 mm.

Images