JP2007198565A - Wheel bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing device having a structure of connecting a hub ring to a constant velocity universal joint for suppressing the slipping of the hub ring relative to the constant velocity universal joint, which is caused during turning a vehicle. <P>SOLUTION: The wheel bearing device comprises an outer ring 104 having double-row raceway surfaces formed on the inner periphery, a shoulder part 130 of the hub ring 101 and the constant velocity universal joint 105 having raceway surfaces 106, 107 formed on the outer periphery in opposition to the raceway surfaces 110, 111 of the outer ring 104, and double-row rolling elements 102, 103 mounted between the outer ring 104 and each of the raceway surfaces 106, 107 of the shoulder part 130 of the hub ring 101 and the constant velocity universal joint 105, the hub ring 101 being connected to an outside joint member 121 of the constant velocity universal joint 105. A stem part 127 of the outside joint member 121 is inserted into the inner diameter of the hub ring 101 and spline-fitted thereto, and the shaft end of the stem part 127 is welded to the end face 134 of the hub ring 101 into one unit. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel bearing device, and more particularly, to a driving wheel bearing device that rotatably supports driving wheels (front wheels of FF vehicles, rear wheels of FR vehicles, all wheels of 4WD vehicles) with respect to a suspension device of an automobile. About.

  BACKGROUND ART There are two types of wheel bearing devices for automobiles, one for driven wheels and one for driving wheels, and various types have been proposed according to the respective applications. For example, FIG. 2 shows a bearing device for a drive wheel, which includes a hub wheel 1, double-row rolling elements 2 and 3, an outer ring 4, and a constant velocity universal joint 5 as main components (for example, see Patent Document 1).

  The hub wheel 1 has a raceway surface 6 on the outboard side formed on the outer peripheral surface thereof, and includes a wheel mounting flange 8 for mounting a wheel (not shown). Hub bolts 9 for fixing the wheel disc are implanted at equal intervals in the circumferential direction of the wheel mounting flange 8. The stem portion 27 of the outer joint member 21 of the constant velocity universal joint 5 is press-fitted into the inner diameter of the hub wheel 1 to be fitted by spline, and the inboard raceway surface 7 is fitted to the outer peripheral surface of the shoulder portion 30 of the outer joint member 5. Is formed. Thus, the outboard side raceway surface 6 formed on the outer peripheral surface of the hub wheel 1 and the inboard side raceway surface 7 formed on the outer peripheral surface of the shoulder portion 30 of the constant velocity universal joint 5 are double-rowed. The orbital plane is constructed. A spline 29 is formed on the inner diameter of the hub wheel 1.

  The outer ring 5 is formed with double-row raceway surfaces 10 and 11 facing the raceway surfaces 6 and 7 of the hub wheel 1 and the constant velocity universal joint 5 on the inner peripheral surface, and is attached to the vehicle body (not shown). A flange 12 is provided. The vehicle body mounting flange 12 is bolted to a knuckle extending from a vehicle suspension system (not shown) using a mounting hole 13.

  The bearing portion 14 has a double-row angular contact ball bearing structure and has raceway surfaces 6 and 7 formed on the outer peripheral surface of the hub wheel 1 and the constant velocity universal joint 5 and a raceway surface 10 formed on the inner peripheral surface of the outer ring 4. 11, the rolling elements 2 and 3 are interposed, and the rolling elements 2 and 3 in each row are supported by the cages 15 and 16 at equal intervals in the circumferential direction. A pair of seals that seal the annular space between the outer ring 4, the hub wheel 1, and the constant velocity universal joint 5 so as to be in sliding contact with the outer peripheral surfaces of the hub wheel 1 and the constant velocity universal joint 5 at both ends of the bearing portion 14. 17 and 18 are fitted to the inner diameters at both ends of the outer ring 4 to prevent leakage of grease filled inside and entry of water and foreign matters from the outside.

  The constant velocity universal joint 5 includes an outer joint member 21 in which a track groove 19 is formed on an inner peripheral surface, and an inner joint member 22 in which a track groove 20 facing the track groove 19 of the outer joint member 21 is formed on an outer peripheral surface. And a ball 23 incorporated between the track groove 19 of the outer joint member 21 and the track groove 20 of the inner joint member 22, and the ball 23 interposed between the outer joint member 21 and the inner joint member 22 in the circumferential direction. The cage 24 is held at equal intervals. The intermediate shaft 25 is press-fitted into the shaft hole of the inner joint member 22 and is spline-fitted.

  The outer joint member 21 includes a mouth portion 26 that houses the inner joint member 22, the cage 24, and the ball 23, and a stem portion 27 that extends integrally from the mouth portion 26 in the axial direction and has a spline 28 formed on the outer peripheral surface thereof. . In addition, by tightening and fixing a bellows-like boot (not shown) between the outer joint member 21 and the intermediate shaft 25 with a boot band, grease leaks to the outside or water or dust enters the joint from the outside. And other foreign matters are prevented from entering.

  As a means for connecting the constant velocity universal joint 5 and the hub wheel 1, the stem portion 27 of the outer joint member 21 of the constant velocity universal joint 5 is inserted into the inner diameter of the hub wheel 1, and the shaft end of the stem portion 27 is connected to the hub wheel. 1 is protruded from the outboard side end portion 34 of the steel plate 1, and the protruding portion is plastically deformed outward by swinging caulking, whereby the caulking portion 31 at the shaft end of the stem portion 27 is moved to the outboard side end of the hub wheel 1. It latches to the part 34 (refer FIG. 1 of patent document 1).

Torque can be transmitted by connecting the stem portion 27 and the splines 28 and 29 formed on the hub wheel 1 together. The bearing portion is formed by crimping the stem portion 27 of the outer joint member 21 and the outboard side end portion 34 of the hub wheel 1 in a state in which the pilot portion 32 of the outer joint member 21 and the inboard side end surface 33 of the hub wheel 1 are abutted. 14 is given a preload.
Japanese Patent Laying-Open No. 2003-72308 (FIG. 1)

  By the way, in the bearing device for driving wheels disclosed in Patent Document 1 described above, between the caulking portion 31 of the stem portion 27 of the outer joint member 21 and the outboard side end portion 34 of the hub wheel 1 when the vehicle turns. There is a risk of slipping. When such relative slip occurs, the caulking portion 31 of the constant velocity universal joint 5 or the inboard side end portion 34 of the hub wheel 1 is worn.

  Accordingly, the present invention has been proposed in view of the above-described problems, and the object of the present invention is, for example, a hub wheel that occurs when a vehicle turns in a connection structure between a hub wheel and a constant velocity universal joint. An object of the present invention is to provide a wheel bearing device capable of suppressing relative sliding of a speed universal joint.

  As technical means for achieving the above-mentioned object, the present invention provides an outer member in which a double-row raceway surface is formed on the inner periphery and a raceway surface on the outer periphery that faces the raceway surface of the outer member. An inner member including the formed hub ring, and a double row rolling element interposed between the raceway surfaces of the outer member and the inner member, and the hub ring of the inner member and the constant velocity universal joint In the wheel bearing device that is connected to the outer joint member, the stem portion of the outer joint member is press-fitted into the inner diameter of the hub wheel and spline-fitted, and the shaft end of the stem portion is welded and integrated with the end surface of the hub wheel. Features.

  In the present invention, the stem portion of the outer joint member is press-fitted into the inner diameter of the hub wheel, and the spline fitting is performed. There is no relative slip between the stem portion of the wheel and the end of the hub wheel. As a result, wear of the stem portion of the constant velocity universal joint or the end portion of the hub wheel does not occur.

  According to the present invention, the inner member in the above-described configuration is abutted against the hub ring forming one of the raceway surfaces of the double row and the end of the hub wheel, The present invention can be applied to a wheel bearing device constituted by an outer joint member of a constant velocity universal joint having a shoulder portion forming the other raceway surface.

  Further, in the present invention, the inner member in the above-described configuration is fitted to the hub wheel formed on the outer peripheral surface with one raceway surface and a small diameter step portion of the double row raceway surfaces, and the small diameter step portion, The present invention can also be applied to a wheel bearing device including an inner ring in which the other track surface of the double row track surfaces is formed on the outer peripheral surface.

  According to the present invention, the stem portion of the outer joint member is press-fitted into the inner diameter of the hub wheel, and the spline fitting is performed. Since there is no relative slip between the stem portion of the universal joint and the end portion of the hub ring, wear of the stem portion of the constant velocity universal joint or the end portion of the hub ring does not occur.

  As a result, it is possible to prevent rattling from occurring in the connecting structure of the hub wheel and the constant velocity universal joint, so that the rigidity of the wheel bearing device can be improved, and sufficient durability against repeated moment loads. Can be ensured, and harmful drive system vibrations can be suppressed to improve the drive feeling of the vehicle.

  An embodiment of a wheel bearing device according to the present invention will be described in detail below. The embodiment shown in FIG. 1 is a drive wheel bearing device, and includes a hub wheel 101, double-row rolling elements 102 and 103, an outer ring 104, and a constant velocity universal joint 105 as main components.

  The hub wheel 101 is provided with a wheel mounting flange 108 for mounting a wheel (not shown) while an outboard raceway surface 106 is formed on the outer peripheral surface thereof. Hub bolts 109 for fixing the wheel disc are implanted at equal intervals in the circumferential direction of the wheel mounting flange 108. The stem portion 127 of the constant velocity universal joint 105 is press-fitted into the inner diameter of the hub wheel 101 and is spline-fitted, and the inboard raceway surface 107 is formed on the outer peripheral surface of the shoulder 130 of the outer joint member 121. . A spline 129 is formed on the inner diameter of the hub wheel 101.

  In this way, the hub wheel 101 and the shoulder 130 of the constant velocity universal joint 105 constitute an inner member. The outboard side raceway surface 106 formed on the outer peripheral surface of the hub wheel 101 and the inboard side raceway surface 107 formed on the outer peripheral surface of the shoulder 130 of the constant velocity universal joint 105 are double-rowed. Configure the raceway surface.

  The outer ring 104 which is an outer member is formed with double-row raceway surfaces 110 and 111 which are opposed to the raceway surfaces 106 and 107 of the hub wheel 101 and the constant velocity universal joint 105 on the inner peripheral surface, and is formed on the vehicle body (not shown). A vehicle body mounting flange 112 for mounting is provided. The vehicle body mounting flange 112 is bolted to a knuckle extending from a vehicle suspension system (not shown) by using a mounting hole 113.

  The bearing portion 114 has a double-row angular contact ball bearing structure and has raceway surfaces 106 and 107 formed on the outer peripheral surface of the hub wheel 101 and the constant velocity universal joint 105 and a raceway surface 110 formed on the inner peripheral surface of the outer ring 104. The rolling elements 102 and 103 are interposed between the rolling elements 102 and 103, and the rolling elements 102 and 103 in each row are supported by the cages 115 and 116 at equal intervals in the circumferential direction. A pair of seals that seal the annular space between the outer ring 104, the hub ring 101, and the constant velocity universal joint 105 at both ends of the bearing 114 so as to be in sliding contact with the outer peripheral surface of the hub ring 101 and the constant velocity universal joint 105. 117 and 118 are fitted to the inner diameters of both ends of the outer ring 104 to prevent leakage of grease filled inside and intrusion of water and foreign matters from the outside.

  The constant velocity universal joint 105 includes an outer joint member 121 having a track groove 119 formed on the inner peripheral surface and an inner joint member 122 having a track groove 120 facing the track groove 119 of the outer joint member 121 formed on the outer peripheral surface. The ball 123 incorporated between the track groove 119 of the outer joint member 121 and the track groove 120 of the inner joint member 122, and the ball 123 circumferentially interposed between the outer joint member 121 and the inner joint member 122. The cage 124 is held at equal intervals. The intermediate shaft 125 is press-fitted into the shaft hole of the inner joint member 122 and is spline-fitted.

  The outer joint member 121 includes a mouth portion 126 that houses the inner joint member 122, the cage 124, and the ball 123, and a stem portion 127 that extends integrally from the mouth portion 126 in the axial direction and has a spline 128 formed on the outer peripheral surface thereof. . In addition, by tightening and fixing a bellows-like boot (not shown) between the outer joint member 121 and the intermediate shaft 125 by a boot band, grease leaks to the outside or water, dust, etc. from the outside to the inside of the joint. Prevents foreign material from entering.

  As a means for connecting the constant velocity universal joint 105 and the hub wheel 101, the stem portion 127 of the outer joint member 121 of the constant velocity universal joint 105 is press-fitted into the inner diameter of the hub wheel 101 and is spline-fitted. The shaft end is welded and integrated at the outboard side end surface 134 of the hub wheel 101.

  Torque can be transmitted by connecting the stem portion 127 and the splines 128 and 129 formed on the hub wheel 101 together. The bearing portion 114 is welded to the stem portion 127 of the outer joint member 121 and the outboard side end surface 134 of the hub wheel 101 in a state where the pilot portion 132 of the outer joint member 121 and the inboard side end surface 133 of the hub wheel 101 are in contact with each other. Preload is applied.

  In the wheel bearing device of this embodiment, the stem portion 127 of the outer joint member 121 is press-fitted into the inner diameter of the hub wheel 101 to be spline-fitted, and the shaft end of the stem portion 127 is connected to the outboard side end surface 134 of the hub wheel 101. As a result of the welding integration, relative slip does not occur between the stem portion 127 of the outer joint member 121 and the end portion of the hub wheel 101 when the vehicle turns. As a result, the stem 127 of the outer joint member 121 or the end of the hub wheel 101 is not worn.

  In the spline fitting structure of the hub wheel 101 and the constant velocity universal joint 105, the spline 128 of the stem portion 127 of the constant velocity universal joint 105 is hardened by heat treatment before the constant velocity universal joint 105 is assembled to the hub wheel 101. Is normal. On the other hand, in the connection structure of the hub wheel 101 and the constant velocity universal joint 105, the shaft end of the stem portion 127 is welded to the end portion of the hub wheel 101, so the welded portion 131 becomes a cross-hatched portion in the figure. Since the spline tip portion of the stem portion 127 is hardened due to the heat effect during welding, it is necessary to perform heat treatment over the entire spline axial direction of the stem portion 127 before the constant velocity universal joint 105 is assembled to the hub wheel 101. Thus, only the region having a short axial length excluding the spline tip portion need only be cured by heat treatment, so that the heat treatment time can be shortened and workability can be improved.

  Moreover, it is preferable to set the outer diameter of the welding part 131 larger than the outer diameter of the intermediate shaft 125 connected by spline fitting to the inner joint member 122 of the constant velocity universal joint 105. By doing so, the strength of the shaft end of the stem portion 127 of the constant velocity universal joint 105 can be improved as compared with the intermediate shaft 125, and the strength in the connection structure between the hub wheel 101 and the constant velocity universal joint 105 is ensured. be able to.

  Further, the welded portion 131 may be either the entire circumference along the circumferential direction of the stem portion 127 or a plurality of locations. If the welded portion 131 is the entire circumference along the circumferential direction of the stem portion 127, the strength in the connection structure between the hub wheel 101 and the constant velocity universal joint 105 can be sufficiently secured. On the other hand, if the welding part 131 is a plurality of locations along the circumferential direction, the welding work can be shortened and workability can be improved.

  As a welding technique, any of laser welding, electron beam welding, FSW (friction stir welding), and arc welding can be employed. For example, when electron beam welding with a high degree of freedom of beam irradiation is adopted, medium carbon steel is used for hub rings and the like by adjusting the focal position of the beam and providing a preheating process or a post heat treatment process at about 500 ° C. However, no burning cracks occur.

  Further, a beam emitted in vacuum can be freely set at a focal position by an electromagnetic focusing lens, and a deep and sharp bead can be formed as compared with laser beam welding or plasma welding. As a result, the heat influence on the bearing raceway can be minimized.

  Further, by adjusting the focal position by the electromagnetic focusing lens and interposing the deflection lens between the welded parts, XY coordinates can be given to the deflection field, and the beam can be freely moved to the designated coordinates. Since the bead surface formed by such electron beam welding is hardly oxidized, not only the appearance of the product but also the stable quality and cleanliness of the processing environment can be maintained.

  As another welding method, in the case of laser welding using a laser as a heat source, heat concentration is high and low heat input welding is possible. In particular, laser welding having a high energy density and excellent high speed is effective.

  FSW (friction stir welding method) is a non-melting joining method of iron-based materials made of microcrystalline materials, and is a joining method that maintains particularly excellent characteristics such as strength and corrosion resistance of the microcrystalline materials. This FSW (friction stir welding method) is a method in which the frictional heat generated at the joint easily becomes a high temperature below the melting point, causes plastic flow in the metal workpiece, and stirs the metal parts on both sides. Depending on the shape of the surface, linear bonding or curved bonding is possible.

  In the embodiment described above, the stem portion 127 of the constant velocity universal joint 105 is illustrated as a solid type. However, the present invention is not limited to this and can be applied to a type having a hollow stem portion. . When applied to a constant velocity universal joint having such a hollow stem portion, it is possible to improve heat dissipation during welding and to avoid thermal adverse effects during welding. In addition, the weight of the wheel bearing device can be reduced.

  In the embodiment described above, one of the double row raceway surfaces formed on the inner member, that is, the inboard side raceway surface 107 is formed on the outer peripheral surface of the shoulder 130 of the constant velocity universal joint 105. However, the present invention is not limited to this, and a small-diameter step portion is formed at the inboard side end portion of the hub wheel, and a separate diameter portion is provided at the small-diameter step portion. The present invention can also be applied to a wheel bearing device of a type in which an inner ring is press-fitted and an inboard raceway surface is formed on the outer peripheral surface of the inner ring.

It is sectional drawing which shows the wheel bearing apparatus in embodiment of this invention. It is sectional drawing which shows the prior art example of the wheel bearing apparatus.

Explanation of symbols

101 Inner member (hub ring)
102,103 rolling element 104 outer member (outer ring)
105 constant velocity universal joint 106,107 raceway surface 110,111 raceway surface 121 outer joint member 127 stem portion 130 shoulder portion 131 welded portion

Claims (3)

  An outer member having a double-row raceway surface formed on the inner periphery, an inner member including a hub ring having a raceway surface on the outer periphery facing the raceway surface of the outer member, and the outer member and the inner member A wheel bearing device comprising: a double row rolling element interposed between the respective raceway surfaces of the direction member; and the hub ring of the inner member and the outer joint member of the constant velocity universal joint connected to each other. A wheel bearing device, wherein a stem portion of an outer joint member is press-fitted into an inner diameter of a wheel and is spline-fitted, and a shaft end of the stem portion is welded and integrated with an end surface of the hub wheel.   The inner member is abutted against a hub ring that forms one raceway surface of the double row raceway surfaces, and an end portion of the hub wheel to form the other raceway surface of the double row raceway surfaces. The wheel bearing device according to claim 1, comprising a constant velocity universal joint outer joint member having a shoulder portion.   The inner member is fitted to the small-diameter step portion and the other one of the double-row raceway surfaces, and a hub wheel having one raceway surface and a small-diameter step portion formed on the outer peripheral surface of the double-row raceway surfaces. The wheel bearing device according to claim 1, comprising an inner ring having a raceway surface formed on an outer peripheral surface thereof.

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