Wheel bearing device

Abstract

The purpose of the present invention is to make it possible to easily confirm spline fitting during assembly of a vehicle, and to improve workability and assemblability without using additional components. A wheel bearing device 1, wherein: a hub ring 3 has a protrusion H1 that protrudes from the inner peripheral surface of a through-hole 3e toward the inside-diameter side, and a protrusion H2 that protrudes from the inner peripheral surface of the through-hole 3e toward the inside-diameter side on the other axial-direction side from the protrusion H1; a shaft part 27 has a protrusion C2 that protrudes from the outer peripheral surface of the shaft part 27 toward the outside-diameter side; the inside diameter h2 of the protrusion H2 and the outside diameter c3 of the protrusion C2 have the relationship (inside diameter h2 of protrusion H2) < (outside diameter c3 of protrusion C2); the protrusion H2 and the protrusion C2 can be elastically deformed, by axial-direction pressing force, so that the inside diameter h2 becomes large enough for the protrusion C2 to pass through; and in a state where a joint-side spline 262a and a hub-ring-side spline 31a are spline-fitted together, the protrusion C2 is positioned between the protrusion H1 and the protrusion H2 in the axial direction.

Description

Wheel bearing device

[0001] The present invention relates to a wheel bearing device.

[0002] Conventionally, there is a wheel bearing device that rotatably supports a wheel in a suspension device of a vehicle such as a passenger car and an SUV. The outer peripheral surface of a stem extending in the axial direction of a constant velocity joint is spline-fitted to the inner diameter portion of a hub ring which is an inner member, so that the hub ring and the constant velocity joint are coupled so as to be able to transmit torque. The constant velocity joint includes an outer joint member, an inner joint member, balls incorporated between the outer joint member and the inner joint member, and a retainer for holding the balls. The stem that is spline-fitted to the hub ring is possessed by the outer joint member.

[0003] In such a wheel bearing device, the axial end face of the hub ring and the axial end face of the outer joint member are in contact with each other. When a driving force is input to the outer joint member, relative slippage may occur between the hub ring and the outer joint member, generating abnormal noises such as rattling noises.

[0004] Therefore, in order to suppress the relative slippage occurring between the hub ring and the outer joint member and prevent the generation of abnormal noises, a wheel bearing device having a configuration in which the axial end face of the hub ring and the axial end face of the outer joint member are spline-fitted has been devised (see Patent Document 1).

[0005] In a wheel bearing device having a configuration in which the axial end face of the hub ring and the axial end face of the outer joint member are spline-fitted, as shown in FIG. 5 of Patent Document 1, with the axial end face of the hub ring and the axial end face of the outer joint member being in contact, there is one in which the hub ring and the outer joint member are fastened by screwing fastening bolts to the outer joint member.

[0006] In the wheel bearing device shown in FIG. 5 of Patent Document 1, the axial end face of the hub ring and the axial end face of the outer joint member have an inner diameter side annular portion and an outer diameter side annular portion. One is spline-fitted, and the other forms a flat surface and is made to adhere to prevent the intrusion of mud and water.

[0007] In Patent Document 2, a snap ring is attached to the outer joint member, and the snap ring is hooked onto a step formed on the inner diameter of the hub ring to prevent the outer joint member or the hub ring from falling off.

[0008] Japanese Patent Publication No. 2008-174178, German Patent No. 102022100133 Specification

[0009] However, the configurations shown in Patent Documents 1 and 2 have the problem that it is difficult to confirm that the splines are engaged when assembling the vehicle. Also, when the fastening bolts are not screwed in during vehicle assembly or repair, the hub ring or outer joint member may fall off, worsening the ease of assembly. In the configuration shown in Patent Document 2, it is necessary to add a snap ring, which increases the number of parts that make up the wheel bearing device.

[0010] This invention has been made in view of the above circumstances, and provides a wheel bearing device that allows for easy confirmation of spline fitting during vehicle assembly and improves workability and assembly efficiency without the use of additional parts.

[0011] That is, the wheel bearing device comprises an outer member having double rows of outer raceway surfaces on its inner circumference, a hub ring having a through hole that penetrates axially through its inner diameter portion and an outer circumference extending axially, and at least one inner ring press-fitted onto the outer circumference of the hub ring, an inner member having double rows of inner raceway surfaces opposite to the double rows of outer raceway surfaces, double rows of rolling elements rotatably housed between the raceway surfaces of the outer member and the inner member, a mouth portion that is rotatably connected to a shaft, and an outer coupling member having a shaft portion that protrudes axially from the mouth portion and is inserted into the through hole of the hub ring, wherein the other axial end face of the inner member and the one axial end face of the mouth portion are spline-fittable, and the hub ring is from the inner circumferential surface of the through hole The hub ring has a projection H1 that protrudes inward, and a projection H2 that protrudes inward from the inner circumferential surface of the through hole on the other axial side of projection H1. The shaft portion has a projection C2 that protrudes outward from the outer circumferential surface of the shaft portion. The inner diameter h2 of projection H2 and the outer diameter c3 of projection C2 have the relationship (inner diameter h2 of projection H2) < (outer diameter c3 of projection C2). The projection H2 of the hub ring and the projection C2 of the shaft portion are elastically deformable by axial pressure so that the inner diameter h2 becomes large enough for projection C2 to pass through. In a state where the other axial end face of the inner member and the one axial end face of the mouse portion are spline fitted together, the projection C2 of the shaft portion is located between the projection H1 and projection H2 of the hub ring in the axial direction.

[0012] According to the present invention, work efficiency can be improved by easily confirming the spline fitting between the outer joint member and the hub wheel. Furthermore, assembly can be improved by preventing the hub wheel or outer joint member from falling off when the fastening bolts are not screwed in.

[0013] This is a side cross-sectional view showing a wheel bearing device. This is a side cross-sectional view showing projections H1, H2, and recess H3 formed in the through hole of the hub ring. This is a side cross-sectional view showing projections C1, C2, and recess C3 formed on the shaft portion of the outer joint member. This is a side cross-sectional view showing the state in which the shaft portion of the outer joint member is inserted into the through hole of the hub ring, and the outer end of projection H1 to the inner end of projection H2 is located within the range from the outer end of projection C1 to the inner end of projection C2. This is a side cross-sectional view showing the state in which the axial direction of the shaft portion inserted into the through hole is inclined with respect to the axial direction of the through hole, and the joint-side spline and the hub ring-side spline are engaged. This is a side cross-sectional view showing the state in which the axial direction of the shaft portion inserted into the through hole is inclined with respect to the axial direction of the through hole, and the joint-side spline and the hub ring-side spline are not engaged. This is a side cross-sectional view showing the state in which projection C2 of the shaft portion passes through projection H2 of the through hole. This is a side cross-sectional view showing the state in which projection C2 of the shaft portion is fitted into the recess H3 of the hub ring. This is a side cross-sectional view showing a modified example of the shaft portion.

[0014] The embodiments for carrying out the present invention will be described below with reference to the attached drawings.

[0015] [Wheel Bearing Device] 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.

[0016] In the following explanation, "axial direction" refers to the direction along the rotation axis X of the wheel bearing device 1. Furthermore, "outer side" refers to one axial side, which is the wheel side of the wheel bearing device 1 when it is mounted on the vehicle body, and "inner side" refers to the other axial side, which is the vehicle body side of the wheel bearing device 1 when it is mounted on the vehicle body.

[0017] The wheel bearing device 1 comprises an outer ring 2 which is an outer member, a hub ring 3 and an inner ring 4 which are inner members, two rows of inner ball rows 5 and outer ball rows 6 which are rolling rows, an inner sealing member 9, an outer sealing member 10, and an outer joint member 21 of a constant velocity universal joint 20.

[0018] An inner side opening 2a is formed at the inner side end of the outer ring 2, into which the inner side sealing member 9 can be fitted. An outer side opening 2b is formed at the outer side end of the outer ring 2, into which the outer side sealing member 10 can be fitted.

[0019] The annular space S formed by the outer ring 2 and the hub ring 3 is sealed by fitting the inner side sealing member 9 into the inner side opening 2a, which is the inner side opening end of the annular space S, and by fitting the outer side sealing member 10 into the outer side opening 2b, which is the outer side opening end of the annular space S.

[0020] The inner circumferential surface 2p of the outer ring 2 has an inner outer raceway surface 2c and an outer outer raceway surface 2d. The outer circumferential surface 2o of the outer ring 2 has a vehicle body mounting flange 2e integrally formed thereon for attaching the outer ring 2 to the vehicle body side member. The vehicle body mounting flange 2e is provided with bolt holes into which fastening members (in this case, bolts) that fasten the vehicle body side member and the outer ring 2 are inserted.

[0021] A smaller diameter stepped portion 3a is formed at the inner end of the outer circumferential surface 3o of the hub wheel 3, which is smaller in diameter than the outer end. A shoulder portion 3i is formed at the outer end of the smaller diameter stepped portion 3a on the hub wheel 3.

[0022] A wheel mounting flange 3b for attaching a wheel is integrally formed on the outer end of the hub wheel 3. The wheel mounting flange 3b is provided with a plurality of bolt holes 3f for fastening the hub wheel 3 to a wheel or brake component.

[0023] The outer circumferential surface 3o of the hub wheel 3 is provided with an inner raceway surface 3c on the outer side, facing the outer raceway surface 2d of the outer ring 2. In other words, the inner raceway surface 3c is formed on the outer side of the inner member by the hub wheel 3. A seal land portion 3d is formed on the base side of the wheel mounting flange 3b of the hub wheel 3, with which the seal lip of the outer side seal member 10 slides.

[0024] A through hole 3e is formed in the inner diameter portion of the hub wheel 3, along the axial direction, and into which the outer joint member 21 of the constant velocity universal joint 20 is connected. The through hole 3e penetrates the hub wheel 3 in the axial direction.

[0025] An inner ring 4 is provided on the small-diameter stepped portion 3a of the hub ring 3. The inner ring 4 is fixed to the small-diameter stepped portion 3a of the hub ring 3 by press-fitting and crimping. The inner ring 4 applies preload to the rolling rows, which consist of the inner ball row 5 and the outer ball row 6.

[0026] The inner ring 4 has an inner end face 4b at its inner end and an outer end face 4c at its outer end. A crimped portion 3h is formed at the inner end of the small-diameter stepped portion 3a of the hub ring 3, crimped to the inner end face 4b of the inner ring 4. The inner ring 4 is fixed in the axial direction by the crimped portion 3h.

[0027] The crimped portion 3h is formed by plastically deforming the inner end, which is one end of the small-diameter stepped portion 3a in the axial direction, toward the outer diameter. The crimped portion 3h has an inner end face 31 that faces the inner side in the axial direction. A hub ring side spline 31a is formed on the inner end face 31. The inner end face 31 of the crimped portion 3h is an example of the other end face in the axial direction of the inner member.

[0028] The outer circumferential surface 4o of the inner ring 4 is provided with an inner raceway surface 4a that faces the outer raceway surface 2c on the inner side of the outer ring 2. In other words, the inner raceway surface 4a is formed on the inner side of the inner member by the inner ring 4.

[0029] The inner ball row 5 and the outer ball row 6, which are rolling elements, are composed of multiple balls 7, which are rolling elements, held by a retainer 8.

[0030] The inner ball row 5 is rotatably sandwiched between the inner raceway surface 4a of the inner ring 4 and the inner outer raceway surface 2c of the outer ring 2. The outer ball row 6 is rotatably sandwiched between the inner raceway surface 3c of the hub ring 3 and the outer outer raceway surface 2d of the outer ring 2. In other words, the inner ball row 5 and the outer ball row 6 are rotatably housed between the raceway surfaces of the outer and inner members. The inner ring 4 applies preload to the rolling rows, the inner ball row 5 and the outer ball row 6.

[0031] In the wheel bearing device 1, a double-row angular contact ball bearing is constructed from an outer ring 2, a hub ring 3 and an inner ring 4, an inner ball row 5, and an outer ball row 6. Alternatively, the wheel bearing device 1 may be configured with a double-row tapered roller bearing instead of the double-row angular contact ball bearing.

[0032] The constant velocity universal joint 20 comprises an outer joint member 21, an inner joint member (not shown), a ball (not shown) incorporated between the outer joint member 21 and the inner joint member, and a retainer (not shown) that holds the ball. The end of a shaft 28, to which driving force from a drive source such as an engine or motor is input, is press-fitted into the inner joint member. The outer joint member 21 has a mouth portion 26 that houses the internal components consisting of the inner joint member, the ball, and the retainer, and a shaft portion 27 that protrudes from the mouth portion 26 toward the outer side in the axial direction. The mouth portion 26 of the outer joint member 21 is rotatably connected to the shaft 28 via the inner joint member, the ball, and the retainer.

[0033] The mouse portion 26 has an outer peripheral surface 261 and an outer end surface 262 located on the outer side of the outer peripheral surface 261. The outer end surface 262 is an end surface that faces the outer side in the axial direction. The outer end surface 262 is an example of an axial one-sided end surface of the mouse portion.

[0034] A joint-side spline 262a is formed on the outer end face 262. The joint-side spline 262a can be spline-fitted with the hub wheel-side spline 31a of the crimped portion 3h on the hub wheel 3. By spline-fitting the joint-side spline 262a and the hub wheel-side spline 31a, the hub wheel 3 and the outer joint member 21 can rotate as a single unit.

[0035] The shaft portion 27 is inserted into the through hole 3e of the hub wheel 3 from the inner side. The shaft portion 27 has a threaded hole 27a that penetrates axially. A female thread is formed in the threaded hole 27a. With the shaft portion 27 inserted into the through hole 3e of the hub wheel 3, the hub wheel 3 and the outer joint member 21 are fastened together by screwing a bolt 30 into the threaded hole 27a.

[0036] The bolt 30 is inserted into the through hole 3e of the hub wheel 3 from the outer side, and the head 30a of the bolt 30 engages with the stepped surface 3g formed at the outer end of the through hole 3e. The bolt 30 has a threaded portion 30b at its inner end. A male thread is formed on the threaded portion 30b, and the threaded portion 30b is screwed into the threaded hole 27a of the shaft portion 27.

[0037] In the wheel bearing device 1, when assembling the outer coupling member 21 and the hub wheel 3, the shaft portion 27 is inserted into the through hole 3e of the hub wheel 3 from the inner side, and then a bolt 30 is screwed into the threaded hole 27a, thereby completing the fastening of the hub wheel 3 and the outer coupling member 21.

[0038] [Fitting structure between the through hole of the hub wheel and the shaft portion of the outer joint member] The shaft portion 27 of the outer joint member 21 is formed to be fitted into the through hole 3e of the hub wheel 3.

[0039] As shown in Figure 2, the hub wheel 3 has a projection H1 that protrudes inward from the inner circumferential surface of the through hole 3e, a projection H2 that protrudes inward from the inner circumferential surface of the through hole 3e further inward than projection H1, and a recess H3 located between projection H1 and projection H2. Projections H1, H2, and H3 are located at the inner end of the through hole 3e.

[0040] The inner diameter of the protrusion H1 is h1, the inner diameter of the protrusion H2 is h2, and the inner diameter of the recess H3 is h3. The inner diameter h1 of the protrusion H1 is smaller than the inner diameter h2 of the protrusion H2, and the inner diameter h3 of the recess H3 is larger than the inner diameter h1 of the protrusion H1 and the inner diameter h2 of the protrusion H2. The axial length from the outer side end of the protrusion H1 to the inner side end of the protrusion H2 is L1.

[0041] As shown in FIG. 3, the shaft portion 27 of the outer joint member 21 has a protrusion C2 that protrudes from the outer peripheral surface of the shaft portion 27 to the outer diameter side, a protrusion C1 that protrudes from the outer peripheral surface of the shaft portion 27 to the outer diameter side on the outer side of the protrusion C2, and a recess C3 located between the protrusion C1 and the protrusion C2.

[0042] The protrusion C1 has a protrusion C1a, a protrusion C1b located on the inner side of the protrusion C1a, and a step D located between the protrusion C1a and the protrusion C1b. The outer diameter of the protrusion C1a is c1, and the outer diameter of the protrusion C1b is c2. The outer diameter c1 is larger than the outer diameter c2. Therefore, the overall outer diameter of the protrusion C1 is c1. The step D is a tapered surface that tapers inward from the outer side.

[0043] The outer diameter of the protrusion C2 is c3, and the outer diameter of the recess C3 is c4. The outer diameter c3 of the protrusion C2 is larger than the outer diameter c1 of the protrusion C1a. The outer diameter c4 of the recess C3 is smaller than the outer diameter c2 of the protrusion C1b.

[0044] The axial length from the outer side end of the protrusion C1 to the inner side end of the protrusion C2 is L2. The axial length of the shaft portion 27 is c5.

[0045] The inner diameter h1 of the protrusion H1 of the through hole 3e is larger than the outer diameter c1 of the protrusion C1 of the shaft portion 27. That is, the inner diameter h1 of the protrusion H1 and the outer diameter c1 of the protrusion C1 have a relationship of (inner diameter h1 of the protrusion H1) > (outer diameter c1 of the protrusion C1).

[0046] The inner diameter h2 of the protrusion H2 of the through hole 3e is smaller than the outer diameter c3 of the protrusion C2 of the shaft portion 27. That is, the inner diameter h2 of the protrusion H2 and the outer diameter c3 of the protrusion C2 have a relationship of (inner diameter h2 of the protrusion H2) < (outer diameter c3 of the protrusion C2). Also, the inner diameter h2 of the protrusion H2 and the outer diameter c3 of the protrusion C2 have a relationship of 0 mm < (outer diameter c3 - inner diameter h2) ≤ 0.4 mm.

[0047] The axial length L1 from the outer end of the protrusion H1 to the inner end of the protrusion H2 is smaller than the axial length L2 from the outer end of the protrusion C1 to the inner end of the protrusion C2 (axial length L1 < axial length L2).

[0048] As shown in FIG. 4, in a state where the shaft portion 27 of the outer joint member 21 is inserted into the through hole 3e of the hub ring 3 until the crest of the joint side spline 262a and the crest of the hub ring side spline 31a are close to or in contact with each other, in the axial direction, from the outer end of the protrusion C1 to the inner end of the protrusion C2 within the range, from the outer end of the protrusion H1 to the inner end of the protrusion H2 is located.

[0049] Further, when the shaft portion 27 is inserted into the through hole 3e, since the inner diameter h2 of the protrusion H2 is formed smaller than the outer diameter c3 of the protrusion C2 (0 mm < (outer diameter c3 - inner diameter h2)), the protrusion C2 of the shaft portion 27 abuts on the protrusion H2 of the through hole 3e, and the insertion of the shaft portion 27 to the outer side is temporarily restricted.

[0050] Even in a state where the protrusion C2 of the shaft portion 27 abuts on the protrusion H2 of the through hole 3e, the state where from the outer end of the protrusion H1 to the inner end of the protrusion H2 is located within the range from the outer end of the protrusion C1 to the inner end of the protrusion C2 is maintained.

[0051] In the state shown in FIG. 4, the axial direction of the shaft portion 27 and the axial direction of the through hole 3e coincide, and the protrusion C1b of the shaft portion 27 and the protrusion H1 of the hub ring 3 face each other in the radial direction. Note that the axial direction of the shaft portion 27 is a direction along the axis Y (see FIG. 5) of the shaft portion 27.

[0052] Further, the protrusion C1a of the shaft portion 27 is located on the outer side of the protrusion H1 of the hub ring 3. In this case, since the outer diameter c1 of the protrusion C1a in the shaft portion 27 is smaller than the inner diameter h1 of the protrusion H1 in the hub ring 3, when the shaft portion 27 is inserted into the through hole 3e, the protrusion C1a can smoothly pass through the protrusion H1. Furthermore, the protrusion C2 of the shaft portion 27 is located on the inner side of the protrusion H2 of the through hole 3e.

[0053] When inserting the shaft portion 27 into the through hole 3e, it is preferable to insert the shaft portion 27 in a position where the shaft axial direction of the shaft portion 27 coincides with the axial direction of the through hole 3e. However, due to the weight of the outer joint member 21 or the weight of the hub wheel 3, the shaft portion 27 may be inserted in a position where its shaft axial direction is inclined with respect to the axial direction of the through hole 3e. The inclination angle between the shaft axial direction of the shaft portion 27 and the axial direction of the through hole 3e is θ.

[0054] As shown in Figure 5, for example, if the axial direction of the shaft portion 27 is inclined such that the inner side of the shaft portion 27 is lower than the outer side of the through hole 3e, then the projection H2 located at the bottom of the through hole 3e and the projection C2 located at the bottom of the shaft portion 27 come into contact. Specifically, the inner end of projection H2 and the outer end of projection C2 are in contact.

[0055] In this case, projection H2 protrudes inward from the inner circumferential surface of the through hole 3e, and projection C2 protrudes outward from the outer circumferential surface of the shaft portion 27. Therefore, the contact between projection H2 and projection C2 makes it possible to suppress radial movement of the outer joint member 21.

[0056] Furthermore, as shown in Figure 5, when the axial direction of the shaft portion 27 is inclined with respect to the axial direction of the through hole 3e, the projection H1 located at the top of the through hole 3e and the projection C1 located at the top of the shaft portion 27 come into contact.

[0057] In this case, projection H1 protrudes inward from the inner circumferential surface of the through hole 3e, and projection C1 protrudes outward from the outer circumferential surface of the shaft portion 27. Therefore, the contact between projection H1 and projection C1 makes it possible to suppress radial movement of the outer joint member 21.

[0058] Thus, in the wheel bearing device 1, when the axial direction of the shaft portion 27 inserted into the through hole 3e is inclined with respect to the axial direction of the through hole 3e, projections H2 and C2 come into contact, and projections H1 and C1 come into contact, thereby preventing the outer joint member 21 into which the shaft portion 27 is inserted from falling out of the hub wheel 3, and improving the ease of assembly between the hub wheel 3 and the outer joint member 21 without using additional parts.

[0059] Furthermore, when the projection H1 located at the top of the through hole 3e and the projection C1 located at the top of the shaft portion 27 come into contact, the outer end of projection H1 comes into contact with the step D of projection C1. Since the step D is formed as a tapered surface that widens towards the outer side, the contact between projection H1 and step D restricts the movement of the shaft portion 27 inserted into the through hole 3e toward the inner side. This prevents the outer joint member 21 from falling off the hub wheel 3, and improves the ease of assembly between the hub wheel 3 and the outer joint member 21 without using additional parts.

[0060] Furthermore, since the axial length L1 between projections H1 and H2 is smaller than the axial length L2 between projections C1 and C2, when the axial direction of the shaft portion 27 inserted into the through hole 3e is inclined with respect to the axial direction of the through hole 3e, it is possible to bring the inner end of projection H2 into contact with the outer end of projection C2, and also to bring the outer end of projection H1 into contact with the step D of projection C1.

[0061] In this way, the inner end of projection H2 and the outer end of projection C2 come into contact, restricting the shaft portion 27 from moving outwards, and the outer end of projection H1 and the step D of projection C1 come into contact, restricting the shaft portion 27 from moving inwards.

[0062] As a result, when the axial direction of the shaft portion 27 is inclined with respect to the axial direction of the through hole 3e, the axial movement of the shaft portion 27 inserted into the through hole 3e is suppressed, and the outer joint member 21 can be prevented from falling off the hub wheel 3.

[0063] Furthermore, the axial positions of projections H1 and C1 are set so that when the hub wheel 3 and the shaft portion 27 are engaged, and the joint-side spline 262a and the hub wheel-side spline 31a are engaged, the outer end of projection H1 and the step D of projection C1 can come into contact.

[0064] In other words, as shown in Figure 5, when the axial direction of the shaft portion 27 is inclined with respect to the axial direction of the through hole 3e, when the hub wheel 3 and the shaft portion 27 are in a phase where the coupling-side spline 262a and the hub wheel-side spline 31a engage, the lower part of the coupling-side spline 262a and the lower part of the hub wheel-side spline 31a engage, resulting in a spline-fitted state.

[0065] Furthermore, when the spline 262a on the joint side and the spline 31a on the hub wheel side are engaged, the projections H1 and C1 are positioned such that the axial positions of the outer end of projection H1 and the step D of projection C1 coincide. This allows the outer end of projection H1 and the step D of projection C1 to come into contact.

[0066] On the other hand, when the spline 262a on the joint side and the spline 31a on the hub wheel side are not engaged, the projections H1 and C1 do not come into contact between the outer end of projection H1 and the step D of projection C1.

[0067] In other words, as shown in Figure 6, when the axial direction of the shaft portion 27 is inclined with respect to the axial direction of the through hole 3e, and the hub wheel 3 and the shaft portion 27 are in a phase where the coupling-side spline 262a and the hub wheel-side spline 31a do not engage, the lower peaks of the coupling-side spline 262a and the lower peaks of the hub wheel-side spline 31a come into contact, and the coupling-side spline 262a and the hub wheel-side spline 31a do not engage.

[0068] Therefore, when the joint-side spline 262a and the hub-side spline 31a are not engaged, the axial position of the shaft 27 relative to the through hole 3e will be shifted inward by the height of the spline teeth of the joint-side spline 262a and the hub-side spline 31a, compared to when they are engaged.

[0069] As a result, when the axial direction of the shaft portion 27 is inclined with respect to the axial direction of the through hole 3e, the outer end of the projection H1 in the through hole 3e will come into contact with the projection C1a of the shaft 27, and the step D of the shaft 27 will be located on the inner side of the outer end of the projection H1.

[0070] When the outer end of projection H1 and projection C1a of shaft 27 are in contact, the movement of shaft 27 toward the inner side is not restricted. Therefore, when shaft 27 is pulled toward the inner side, shaft 27 can easily be pulled out of the through hole 3e.

[0071] Thus, when the shaft portion 27 inserted into the through hole 3e has its axial direction inclined with respect to the axial direction of the through hole 3e, if the joint-side spline 262a and the hub-wheel-side spline 31a are engaged, the movement of the shaft portion 27 toward the inner side is restricted. If the joint-side spline 262a and the hub-wheel-side spline 31a are not engaged, the shaft portion 27 can easily move toward the inner side.

[0072] Therefore, by inclining the shaft portion 27 inserted into the through hole 3e in the axial direction with respect to the axial direction of the through hole 3e, and pulling the shaft portion 27 toward the inner side, it is possible to easily confirm whether the joint-side spline 262a and the hub wheel-side spline 31a are engaged by observing whether the shaft portion 27 easily moves toward the inner side, thereby improving ease of assembly to the vehicle body.

[0073] Although the assembly method described involves inserting the shaft portion 27 into the through hole 3e of the hub wheel 3 from the inner side, the same applies to the assembly method in which the through hole 3e of the hub wheel 3 is inserted into the shaft portion 27 from the outer side. In this case, it is possible to prevent the hub wheel 3 from falling off the outer joint member 21.

[0074] As shown in Figure 4, when the shaft portion 27 is inserted into the through hole 3e, and the projection C2 of the shaft portion 27 is positioned on the inner side of the projection H2 of the through hole 3e, if the shaft portion 27 is inserted further outward into the through hole 3e, the projection C2 comes into contact with the projection H2 because the inner diameter h2 of the projection H2 is smaller than the outer diameter c3 of the projection C2.

[0075] When the shaft portion 27 is further pressed into the outer side of the through hole 3e with projection C2 in contact with projection H2, projection H2 is elastically deformed by the pressing force from the inner side to the outer side by projection C2 on the shaft portion 27, so that the inner diameter h2 becomes large enough for projection C2 to pass through. In other words, projection H2 on the hub wheel 3 and projection C2 on the shaft portion 27 are elastically deformable by axial pressing force so that the inner diameter h2 becomes large enough for projection C2 to pass through. As a result, as shown in Figure 7, projection C2 on the shaft portion 27 can pass through projection H2 on the through hole 3e.

[0076] Furthermore, when the projection C2 of the shaft portion 27 is able to pass through the projection H2 of the through hole 3e, the spline 262a on the joint side and the spline 31a on the hub wheel side are engaged.

[0077] In this case, if the difference between the outer diameter c3 of projection C2 and the inner diameter h2 of projection H2 exceeds 0.4 mm, the press-fitting ability of the shaft portion 27 into the through hole 3e may be impaired when projection C2 of the shaft portion 27 passes through projection H2 of the through hole 3e. Therefore, the difference between the outer diameter c3 of projection C2 and the inner diameter h2 of projection H2 is set to 0.4 mm or less ((outer diameter c3 - inner diameter h2) ≤ 0.4 mm).

[0078] As shown in Figure 8, after the projection C2 of the shaft portion 27 passes through the projection H2 of the through hole 3e, the projection C2 of the shaft portion 27 becomes fitted into the recess H3 of the hub wheel 3. At this time, the joint-side spline 262a and the hub wheel-side spline 31a are spline-fitted. In other words, when the joint-side spline 262a and the hub wheel-side spline 31a are spline-fitted, the projection C2 of the shaft portion 27 is positioned between the projections H1 and H2 of the through hole 3e in the axial direction.

[0079] A gap exists between the projection C2, which is fitted into the recess H3, and the recess H3, and the projection C2 and the recess H3 are not in contact. In other words, the projection C2 of the shaft portion 27 is fitted into the recess H3 of the hub wheel 3 with a gap between them.

[0080] The protrusion C2 fits into the recess H3 with a gap, allowing the spline engagement state between the joint-side spline 262a and the hub wheel-side spline 31a to be confirmed by moving the hub wheel 3 back and forth in the axial direction, thereby improving work efficiency.

[0081] Furthermore, because projection C2 fits into recess H3 between projections H1 and H2, the hub wheel 3 is prevented from falling off the outer joint member 21 when the bolt 30 is removed during repair, thus improving ease of assembly.

[0082] [Relationship between outer diameter and axial length of the shaft portion] As shown in Figure 3, the axial length c5 of the shaft portion 27 and the outer diameter c1 of the projection C1 have a relationship such that (c5 / c1) < 1.5. This prevents the axial length c5 of the shaft portion 27 from becoming too large, making it possible to reduce the weight of the outer joint member 21.

[0083] [Modification of the shaft portion] The shaft portion 27 can also be formed as shown in Figure 9, shaft portion 27A. The shaft portion 27A differs from the shaft portion 27, which has a projection C1, in that the projection C1 is not formed thereon. The other configurations of the shaft portion 27A are the same as those of the shaft portion 27.

[0084] In the shaft portion 27A, the projection C2 fits into the recess H3 with a gap, allowing the spline fitting state to be confirmed by moving the hub wheel 3 back and forth in the axial direction, thus improving workability. In addition, when the bolt 30 is removed during repair, the hub wheel 3 is prevented from falling off the outer joint member 21, thus improving ease of assembly.

[0085] In the shaft portion 27A, the axial length c5 and the outer diameter c3 of the projection C2 have a relationship such that (c5 / c3) < 1.5. This prevents the axial length c5 of the shaft portion 27A from becoming too large, making it possible to reduce the weight of the outer joint member 21.

[0086] In this embodiment, a third-generation wheel bearing device 1 has been described in which an inner ring 4 having an inner raceway surface 4a on the inner side is press-fitted into a hub ring 3 having an inner raceway surface 3c on the outer side. However, the wheel bearing device is not limited to this, and may also be a second-generation structure in which a pair of inner rings are press-fitted into a hub ring.

[0087] 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.

[0088] This invention can be used in wheel bearing devices.

[0089] 1 Wheel bearing device 2 Outer ring 2c Outer raceway surface (inner side) 2d Outer raceway surface (outer side) 3 Hub ring 3c Inner raceway surface 3e Through hole 4 Inner ring 4a Inner raceway surface 5 Inner side ball row 6 Outer side ball row 20 Constant velocity universal joint 21 Outer joint member 26 Mouth section 27 Shaft section 31 Inner side end face (crimped section) 31a Hub ring side spline 262 Outer side end face (mouth section) 262a Joint side spline C1, C1a, C1b, C2 Projections (on the shaft section) C3 Recess (on the shaft section) c1 Outer diameter (of projections C1 and C1a) c2 Outer diameter (of projection C1b) c3 Outer diameter (of projection C2) c5 Axial length (of the shaft section) D Steps (of projection C1) H1, H2 Projection (of through hole) H3 Recess (of through hole) h1 Inner diameter (of projection H1) h2 Inner diameter (of projection H2) h3 Inner diameter (of recess H3) L1 Axial length (from the outer end of projection H1 to the inner end of projection H2) L2 Axial length (from the outer end of projection C1 to the inner end of projection C2)

Claims

1. A wheel bearing device comprising: an outer member having double rows of outer raceway surfaces on its inner circumference; a hub ring having a through hole penetrating axially through its inner diameter portion and an outer circumferential surface extending axially; and an inner member having double rows of inner raceway surfaces facing the double rows of outer raceway surfaces, with at least one inner ring press-fitted onto the outer circumferential surface of the hub ring; double rows of rolling elements rotatably housed between the raceway surfaces of the outer member and the inner member; a mouth portion rotatably connected to a shaft; and an outer coupling member having a shaft portion protruding axially from the mouth portion and inserted into the through hole of the hub ring, wherein the other axial end face of the inner member and the one axial end face of the mouth portion are spline-fittable, the hub ring having a projection H1 protruding inward from the inner circumferential surface of the through hole, and a projection H2 protruding inward from the inner circumferential surface of the through hole on the other axial side of projection H1, The shaft portion has a projection C2 that protrudes outward from the outer circumferential surface of the shaft portion, the inner diameter h2 of the projection H2 and the outer diameter c3 of the projection C2 have the relationship (inner diameter h2 of projection H2) < (outer diameter c3 of projection C2), the projection H2 of the hub ring and the projection C2 of the shaft portion are elastically deformable by axial pressing force such that the inner diameter h2 becomes a size through which the projection C2 can pass, and the projection C2 of the shaft portion is positioned in the axial direction between the projection H1 and the projection H2 of the hub ring when the other axial end face of the inner member and the one axial end face of the mouse portion are spline fitted together, 2. The wheel bearing device according to claim 1, wherein the shaft portion has a projection C1 that protrudes outward from the outer circumferential surface of the shaft portion on one axial side of the projection C2, and the relationship between the inner diameter h1 of the projection H1 and the outer diameter c1 of the projection C1 is such that (inner diameter h1 of projection H1) > (outer diameter c1 of projection C1).

3. The wheel bearing device according to claim 2, wherein when the axial direction of the shaft portion inserted into the through hole is inclined with respect to the axial direction of the through hole, the projection H2 and the projection C2 come into contact with each other, and the projection H1 and the projection C1 come into contact with each other.

4. The wheel bearing device according to claim 3, wherein the axial length from one axial end of projection H1 to the other axial end of projection H2 is smaller than the axial length from one axial end of projection C1 to the other axial end of projection C2.

5. The wheel bearing device according to claim 3, wherein the projection C1 has a projection C1a having an outer diameter c1, a projection C1b located on the other axial side of the projection C1a and having an outer diameter c2 smaller than the outer diameter c1, and a step D located between the projection C1a and the projection C1b, and when the axial direction of the shaft portion is inclined with respect to the axial direction of the through hole, the projection H2 and the projection C2 come into contact with each other, and the projection H1 comes into contact with the step D.

6. The wheel bearing device according to claim 5, wherein the step D is positioned to contact the projection H1 when the other axial end face of the inner member and the one axial end face of the mouse portion are engaged in the axial direction, and the step D and the projection H1 do not contact when the other axial end face of the inner member and the one axial end face of the mouse portion are not engaged.

7. The wheel bearing device according to claim 1, wherein the hub ring has a recess H3 formed between the projection H1 and the projection H2, and the recess H3 has an inner diameter h3 that is larger than the inner diameter h1 of the projection H1 and the inner diameter h2 of the projection H2, and the axial direction of the shaft portion inserted into the through hole coincides with the axial direction of the through hole, and the other axial end face of the inner member and the one axial end face of the mouse portion are spline fitted together, and the projection C2 of the shaft portion is fitted into the recess H3 of the hub ring with a gap.

8. The wheel bearing device according to claim 1, wherein the axial length c5 of the shaft portion and the outer diameter c3 of the projection C2 have the relationship (c5 / c3) < 1.

5.

9. The wheel bearing device according to claim 2, wherein the axial length c5 of the shaft portion and the outer diameter c1 of the projection C1 have the relationship (c5 / c1) < 1.

5.

10. The wheel bearing device according to claim 1, wherein the inner diameter h2 of projection H2 and the outer diameter c3 of projection C2 have the relationship 0 mm < (outer diameter c3 - inner diameter h2) ≤ 0.4 mm.

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