JP2008183991A - Rear wheel bearing device and drive shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rear wheel bearing device capable of enhancing the assemblability, the performance and the miniaturization. <P>SOLUTION: A hub ring 2, double-row rolling bearings 6, and a hub ring 2 are unitized in the rear wheel bearing device. One inner rolling surface of the rolling bearing 6 is formed on an outer circumference of the hub ring 2, and the other inner rolling surface 19 of the rolling bearing 6 is formed on the outer circumference of an outer joint member 3 of a constant velocity universal joint 4. The constant velocity universal joint 4 comprises an inner joint member 8 having an outer circumferential surface in which ball grooves inclined in the direction opposite to each other with respect to the axis are alternately formed in the circumferential direction, an outer joint member 3 having an inner circumferential surface in which ball grooves inclined in the direction opposite to each other with respect to the axis are alternately formed, and a torque transmission ball 9 built in an intersection part of the ball groove of the inner joint member 8 with the ball groove of the outer joint member 3 inclined in the direction opposite to each other with respect to the axis. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rear wheel bearing device and a drive shaft.

  A so-called drive shaft used in the rear for FR vehicles and 4WD vehicles includes a fixed type constant velocity universal joint 104 on the outboard side (the outer side when assembled in a vehicle) as shown in FIG. A sliding-type constant velocity universal joint (not shown) on the board side (the inner side when assembled in an automobile) is coupled by an intermediate shaft (not shown). The constant velocity universal joint 104 on the outboard side is coupled to a hub wheel 102 that is rotatably supported by a wheel bearing device.

  The wheel bearing device in FIG. 4 is a so-called third generation. The third generation wheel bearing device includes a hub wheel 102 having a flange 101 extending in the outer diameter direction, a constant velocity universal joint 104 to which an outer joint member 103 is fixed to the hub wheel 102, and an outer peripheral side of the hub wheel 102. And an outer member 105 disposed on the outer side.

  The constant velocity universal joint 104 includes an outer joint member 103, an inner joint member 108 disposed in the bowl-shaped portion 107 of the outer joint member 103, and the inner joint member 108 and the outer joint member 103. A ball 109 is provided, and a holder 110 that holds the ball 109. Further, a spline portion 111 is formed on the inner peripheral surface of the center hole of the inner joint member 108, and an end spline portion of an intermediate shaft (not shown) is inserted into the center hole, and the spline portion 111 on the inner joint member 108 side is inserted. And the spline portion on the shaft side are engaged.

  The hub wheel 102 has a cylindrical portion 113 and the flange 101, and a short cylindrical shape in which a wheel and a brake rotor (not shown) are mounted on the outer end surface 114 (end surface on the opposite joint side) of the flange 101. A pilot part 115 is provided in a protruding manner.

  A notch 116 is provided on the outer peripheral surface of the end portion of the cylindrical portion 113 on the side of the flange portion 107, and an inner ring 117 is fitted into the notch 116. A first inner rolling surface 118 is provided in the vicinity of the flange on the outer peripheral surface of the cylindrical portion 113 of the hub wheel 102, and a second inner rolling surface 119 is provided on the outer peripheral surface of the inner ring 117. The flange 101 of the hub wheel 102 is provided with a bolt mounting hole 112, and a hub bolt 116 for fixing the wheel and the brake rotor to the flange 101 is mounted in the bolt mounting hole 112.

  The outer member 105 constituting a part of the rolling bearing is provided with two rows of outer rolling surfaces 120 and 121 on the inner periphery thereof, and a flange (vehicle body mounting flange) 132 on the outer periphery thereof. The first outer rolling surface 120 of the outer member 105 and the first inner rolling surface 118 of the hub wheel 102 face each other, and the second outer rolling surface 121 of the outer member 105 and the second of the inner ring 117 are second. The inner rolling surface 119 faces each other, and a rolling element 122 is interposed between them.

  The stem shaft 123 of the outer joint member 103 is inserted into the cylindrical portion 113 of the hub wheel 102. The stem shaft 123 has a threaded portion 124 formed at the end of the ridged portion, and a spline portion 125 is formed between the threaded portion 124 and the hooked portion 107. A spline portion 126 is formed on the inner peripheral surface (inner diameter surface) of the cylindrical portion 113 of the hub wheel 102, and when the stem shaft 123 is inserted into the cylindrical portion 113 of the hub wheel 102, the spline on the stem shaft 123 side. The portion 125 engages with the spline portion 126 on the hub wheel 102 side. Then, the nut member 127 is screwed onto the threaded portion 124 protruding from the hub wheel 102, and the hub wheel 102 and the stem shaft 123 are fixed.

  However, in the third generation wheel bearing device as shown in FIG. 4, it is necessary to mount the inner ring 117 of the bearing to the hub wheel 102, which increases the number of parts and complicates the mounting operation. For this reason, the third generation wheel bearing device is improved to reduce the weight and size, and to increase the rigidity and durability, the other inner rolling surface of the rolling bearing is arranged outside the constant velocity universal joint. Some are formed on the outer periphery of the joint member. That is, an outer rolling surface is formed on the inner periphery of the outer member of the double row rolling bearing, one inner rolling surface of the rolling bearing is formed on the outer periphery of the hub wheel, and the outer joint of the constant velocity universal joint. There is one in which the other inner rolling surface of the rolling bearing is formed on the outer periphery of the member (that is, a fourth generation structure). In recent years, in a wheel bearing device, in order to improve vehicle responsiveness in an undercarriage of an automobile, reduction in rattling and weight reduction in a constant velocity universal joint are required. The fourth generation corresponds to this request.

  As a typical method of assembling the drive shaft using the above-mentioned four-generation wheel bearing device, the constant velocity universal joint on the inboard side is inserted into the hole of the housing (knuckle) fixed to the suspension. There is a method to follow (Patent Document 1). That is, in the state where the wheel bearing device, the constant velocity universal joint on the outboard side, the intermediate shaft, and the constant velocity universal joint on the inboard side are assembled in advance, the holes of the knuckle are sequentially formed from the constant velocity universal joint side on the inboard side. Let it pass. There is a method in which the stem portion of the constant velocity universal joint on the inboard side is attached by being inserted into a hole of a differential device (differential) at the center of the vehicle body. In addition, as a method of attaching / detaching the constant velocity joint to / from the vehicle, there is a method in which the stem length is made shorter than the shortening stroke of the sliding type constant velocity joint and the suspension is not disassembled (without removing the knuckle) ( Patent Document 2).

In recent years, a constant velocity universal joint on the inboard side and a constant velocity universal joint on the outboard side use a sliding type constant velocity universal joint. In order to improve the NVH of the sliding type constant velocity universal joint, the backlash between the joint track and the ball becomes a point. Typical types include DOJ (EDJ), TJ (ETJ, PTJ), and LJ types. However, DOJ and TJ types are difficult to rattle, and if a negative clearance is used, the operability decreases and the heat generation is large and short. May lead to a lifespan.
JP 2001-171308 A JP-A 61-50831

  In the method described in Patent Document 1, after fixing the hub bearing portion to the knuckle, the inboard side constant velocity universal joint is once slid and contracted by a necessary amount, and then inserted as it is along the differential hole. Will be stepped on.

  However, depending on the structure of the vehicle body and the sliding length of the inboard side constant velocity universal joint, there is a problem that the amount of contraction becomes insufficient and the method is not adopted. When such a problem occurs, it cannot be inserted into the differential hole.

  Further, as described in Patent Document 2, when the stem length is shortened, the connection strength between the constant velocity universal joint and the hub wheel is reduced, and there is a possibility that a stable connection state cannot be maintained.

  In view of the above problems, the present invention provides a rear wheel bearing device and a drive shaft that can improve assembly performance, improve performance, and achieve compactness. With the goal.

  In the rear wheel bearing device of the present invention, a hub wheel having a vehicle body mounting flange, a double row rolling bearing, and a constant velocity universal joint in which a shaft portion of an outer joint member is fitted into the hub wheel are unitized. The double-row rolling bearing has an outer member having a double-row outer rolling surface formed on the inner periphery, and one inner rolling surface of the rolling bearing is It is formed on the outer periphery of the hub wheel, and the other inner rolling surface of this rolling bearing is formed on the outer periphery of the outer joint member of the constant velocity universal joint, and the constant velocity universal joints are in opposite directions with respect to the axis. An inner joint member having an outer peripheral surface in which ball grooves inclined in the circumferential direction are alternately formed and an outer side having an inner peripheral surface in which ball grooves inclined in opposite directions with respect to the axis are alternately formed in the circumferential direction The joint member and the bore of the inner joint member inclined in opposite directions with respect to the axis. It is obtained by a cross groove constant velocity universal joint including a torque transmission balls incorporating the intersection of the ball groove of the groove and the outer joint member.

  In the bearing device for rear wheels of the present invention, the hub wheel having the vehicle body mounting flange and the double row rolling bearing are integrated, and the inner rolling surface of the rolling bearing is formed on the outer periphery of the outer joint member. That is, a so-called four-generation wheel bearing device is configured. Further, by using a cross-groove type constant velocity universal joint as the constant velocity universal joint, the backlash in the circumferential direction can be easily reduced, and the operability is not easily lowered even with a negative clearance.

  The number of the torque transmission balls of the constant velocity universal joint can be ten.

  The drive shaft of the present invention comprises a sliding constant velocity universal joint on the outboard side, a sliding constant velocity universal joint on the inboard side, and an intermediate shaft connecting these constant velocity universal joints, A drive shaft in which a hub wheel having a vehicle body mounting flange, a double row rolling bearing, and a constant velocity universal joint in which a shaft portion of an outer joint member is fitted into the hub wheel are unitized, The double-row rolling bearing has an outer member in which a double-row outer rolling surface is formed on the inner periphery, and one inner rolling surface of the rolling bearing is formed on the outer periphery of the hub wheel, The other inner rolling surface of the rolling bearing is formed on the outer periphery of the outer joint member of the constant velocity universal joint, and the vehicle body mounting flange and the counterpart member on which the vehicle body mounting flange is fixed to the outer periphery of the outer member of the rolling bearing Used for mating with Reference plane is formed, the maximum outer diameter of the constant velocity universal joint on the outboard side than the outer diameter of the reference surface is obtained by the on maximum outer diameter or a constant velocity universal joint small-diameter and the inboard side.

  In the drive shaft of the present invention, on the outboard side, a hub wheel having a vehicle body mounting flange and a double row rolling bearing are integrated, and an inner rolling surface of the rolling bearing is formed on the outer periphery of the outer joint member. . That is, on the outboard side, a so-called four-generation wheel bearing device is configured.

  Also, after the inboard side constant velocity universal joint is inserted into the housing, a method of once fixing the hub bearing part on the outboard side to the knuckle is adopted. In that case, after fixing the hub bearing portion to the knuckle, the inboard constant velocity universal joint is once slid and contracted as much as necessary, and then inserted into the differential hole as it is. In this case, since the constant velocity universal joint on the outboard side and the constant velocity universal joint on the inboard side are slidable constant velocity universal joints, the constant velocity universal joints on the outboard side and the inboard side are slid and contracted. When the stem portion is inserted into the hole of the differential (differential), a sufficient amount of contraction can be ensured.

  The outer constant velocity universal joint on the outboard side and the constant velocity universal joint on the inboard side are inner joint members having outer peripheral surfaces in which ball grooves inclined in opposite directions with respect to the axis are alternately formed in the circumferential direction; An outer joint member having an inner peripheral surface in which ball grooves inclined in opposite directions with respect to the axis are alternately formed in a circumferential direction, and a ball groove and an outer joint of inner joint members inclined in opposite directions with respect to the axis It is a cross groove type constant velocity universal joint provided with a torque transmission ball incorporated at the intersection of the member with the ball groove. At this time, the number of balls of each constant velocity universal joint is preferably ten.

  By using a cross-groove type constant velocity universal joint, it is possible to easily loosen the constant velocity universal joint on the outboard side, and the operability is unlikely to deteriorate even with a negative clearance. In addition, by using a constant velocity universal joint with 10 balls, the maximum outer diameter is reduced and the 4th generation hub unit can be made compact.

  Since the rear-wheel bearing device of the present invention is a four-generation rear-wheel bearing device, the rigidity of the rolling bearing can be improved and the size reduction can be achieved. In addition, by using a cross-groove type constant velocity universal joint as the constant velocity universal joint, it is possible to easily perform backlash in the circumferential direction. The backlash is suppressed and the NVH characteristics are excellent.

  By making the torque transmission balls of the constant velocity universal joint ten, the ball diameter of the constant velocity universal joint can be reduced, the outer diameter of the constant velocity universal joint can be reduced, and the bearing portion is compact. And weight reduction can be achieved. When the number of cross-groove type torque transmitting balls is 10, the angle of intersection β between the ball groove of the inner ring (inner joint member) and the ball groove of the outer ring (outer joint member) with the axis of each inner ring or outer ring is small. Even then, the drive of the cage is stable up to a certain value. This is because the driving force of the torque transmission ball whose wedge angle has been reversed is shared by other torque transmission balls to stabilize the driving of the cage. When the number of torque transmitting balls is ten, the inclination directions of the pair of ball grooves corresponding to the diameter direction provided on the outer ring (outer joint member) or the inner ring (inner joint member) are the same direction. Therefore, the pair of ball grooves can be processed simultaneously, the workability of the ball grooves is good, the productivity is excellent, and the cost can be reduced. On the other hand, in a general cross groove type constant velocity universal joint, the number of torque transmission balls is generally six. For this reason, when assembling a cross groove type constant velocity universal joint to a vehicle, the angle of the joint is taken and hooked when the joint is returned, which deteriorates workability. Further, when the torque transmission ball exists at a certain phase and the operating angle is increased, the wedge angle is reversed, the balance of the force used from the torque transmission ball to the cage is lost, and the cage becomes unstable. In particular, when the angle of intersection between the ball groove of the inner joint member (inner ring) and the ball groove of the outer joint member (outer ring) with the axis of each inner ring or outer ring becomes smaller, the number of torque transmitting balls is limited to six. In such a case, such a phenomenon appears remarkably.

  The drive shaft of the present invention can secure a sufficient amount of contraction when the stem portion is inserted into the hole of the differential (differential) by sliding and contracting the constant velocity universal joint on the outboard side and the inboard side. it can. For this reason, assembly work can be performed easily and reliably.

  By using a cross groove type constant velocity universal joint as the constant velocity universal joint, the constant velocity universal joint can be easily loosened, and even if it is a negative clearance, the operability is unlikely to deteriorate. Thereby, the play in the circumferential direction is suppressed, and a drive shaft excellent in NVH characteristics can be provided.

  By using ten torque transmitting balls, the rolling bearing (bearing portion) can be made compact. On the other hand, if there are six torque transmission balls, the outer diameter of the outer ring (outer joint member) of the constant velocity universal joint is increased, and the knuckle inner diameter and the bearing portion are increased.

  Hereinafter, an embodiment of a bearing device for a rear wheel of the present invention will be described with reference to FIGS. 1 and 2.

  A rear wheel bearing device according to the first embodiment shown in FIG. 1 includes a hub wheel 2 having a flange 1 extending in the outer diameter direction, a constant velocity universal joint 4 to which an outer joint member 3 is fixed to the hub wheel 2, And a rolling bearing 6 disposed on the outer peripheral side of the hub wheel 2.

  The constant velocity universal joint 4 is a cross groove type constant velocity universal joint, and includes an inner joint member 8, an outer joint member 3, a torque transmission ball 9, and a cage 10 as main components. That is, as shown in FIG. 2, the inner joint member 8 in which ball grooves 8a inclined in opposite directions with respect to the axis are formed on the outer peripheral surface alternately in the circumferential direction, and the inner joint member 8 is opposite to the axis on the inner peripheral surface. Of the outer joint member 3 in which the ball grooves 3a inclined in the direction are alternately formed in the circumferential direction, and the ball groove 8a of the inner joint member 8 and the ball groove 3a of the outer joint member inclined in opposite directions with respect to the axis. A plurality of torque transmission balls 9 assembled at the intersection, and between the outer peripheral surface of the inner joint member 8 and the inner peripheral surface of the outer joint member 3, the torque transmission balls 9 are arranged at predetermined intervals in the circumferential direction. And a retainer 10 for retaining.

  The constant velocity universal joint 4 in this case is a float type in which the minimum inner diameter of the cage 10 is smaller than the maximum outer diameter of the inner joint member 8. A spline portion is formed on the inner peripheral surface of the center hole 11 of the inner joint member 8, and an end spline portion of a shaft (not shown) is inserted into the center hole 11, so that the spline portion and the shaft of the inner joint member 8 are inserted. The side spline part is engaged. The outer joint member 3 includes a mouth portion 7 and a hollow shaft 30 that is connected to the mouth portion 7. The mouse portion 7 includes a small-diameter portion 7a on the hollow shaft 30 side, a large-diameter portion 7b on the side opposite to the hollow shaft, and a tapered portion 7c that continuously connects the large-diameter portion 7b and the small-diameter portion 7a. A second inner rolling surface 19 is formed on the small diameter portion 7 a of the mouth portion 7 of the outer joint member 4.

  As shown in FIG. 2, there are ten ball grooves 8 a of the inner joint member 8 and ten ball grooves 3 a of the outer joint member 3, and ten torque transmitting balls 9 are provided.

  The hub wheel 2 includes a cylindrical portion 13 and a flange 1 protruding from the cylindrical portion 13. The hub wheel 2 includes a wheel mounting flange 1 for mounting a wheel (not shown) on the outer peripheral surface thereof. A mounting hole 12 is provided in the flange 1 along the circumferential direction, and a hub bolt 16 is mounted in the mounting hole 12. That is, the brake rotor and the wheel are superimposed on the end face of the flange 1 and fixed by the hub bolt 16. A first inner rolling surface 18 is formed on the outer diameter surface of the cylindrical portion 13 of the hub wheel 2.

  The rolling bearing 6 includes an outer member (outer ring) 5 disposed around the hub wheel 2 and the outer joint member 3, and an outboard-side rolling element interposed between the outer ring 5 and the hub wheel 2. (Ball) 22a, an inboard-side rolling element (ball) 22b interposed between the outer ring 5 and the outer joint member 3, and an outboard side and an inboard having pockets for holding the rolling elements 22a and 22b Side retainer 24. In addition, the direction which becomes an outer side in the state assembled | attached to the motor vehicle is called the outboard side, and the direction which becomes inner side in the state assembled | attached to the motor vehicle is called the inboard side.

  The outer ring 5 is provided with two rows of outer rolling surfaces 20 and 21 on its inner periphery, and a flange (vehicle body mounting flange) 32 on its outer periphery. Then, the first outer rolling surface 20 of the outer ring 5 and the first inner rolling surface 18 of the hub wheel 2 face each other, the second outer rolling surface 21 of the outer ring 5 and the rolling surface 19 of the outer joint member 3. And rolling elements (balls) 22a and 22b are interposed therebetween. Seal members 17a and 17b are press-fitted and fixed to inner peripheral surfaces at both axial ends of the outer ring 5.

  A concave / convex portion 25 is provided on the flange corresponding portion of the inner diameter surface of the hub wheel 2, and at least the concave / convex portion 25 is subjected to thermosetting treatment such as induction hardening. The hollow shaft 30 of the outer joint member 3 is fitted into the hub wheel 2 until the end surface 26 of the hub wheel 2 comes into contact with the end surface 7d (shoulder) of the mouth portion 7. At this time, the fitting portion 31 (corresponding portion of the concavo-convex portion 25) of the hollow shaft 30 is expanded by a diameter expanding tool such as a mandrel. As a result, the fitting portion 31 is bitten into the concavo-convex portion 25 and caulked to integrate the hub wheel 2 and the outer joint member 3 together.

  Thus, in the rear wheel bearing device of the present invention, the hub wheel 2 having the vehicle body mounting flange 1 and the double row rolling bearing 6 are integrated, and the inner side of the rolling bearing 6 is formed on the outer periphery of the outer joint member 3. A running surface 19 is formed. In other words, since it is a four-generation rear wheel bearing device, it is possible to improve the rigidity of the rolling bearing and to make it compact. Further, by using a cross-groove type constant velocity universal joint as the constant velocity universal joint 4, circumferential play can be easily reduced, and even if it is a negative clearance, the operability is not easily lowered. For this reason, the play in the circumferential direction is suppressed, and the NVH characteristics are excellent.

  By using ten torque transmitting balls 9 of the constant velocity universal joint 4, the ball diameter of the constant velocity universal joint 4 can be reduced, and the outer diameter of the constant velocity universal joint 4 can be reduced. The bearing portion can be made compact and light. When the number of cross groove type torque transmitting balls 9 is 10, the ball groove 8a of the inner joint member 8 and the ball groove 3a of the outer joint member 3 are in contact with the axis of the inner joint member 8 or the outer joint member 3, respectively. Even when the crossing angle β decreases, the driving of the cage 10 is stable up to a certain value. This is because the driving force of the torque transmission ball 9 whose wedge angle has been reversed is shared by the other torque transmission balls 9 to stabilize the driving of the cage 10. When the number of the torque transmission balls 9 is 10, the twist directions of the pair of ball grooves corresponding to the diameter direction provided in the outer joint member 3 or the inner joint member 8 are the same direction. Therefore, the pair of ball grooves can be processed simultaneously, the workability of the ball grooves is good, the productivity is excellent, and the cost can be reduced.

  Next, FIG. 3 shows a drive shaft using the rear wheel bearing device according to the present invention, in which the constant velocity universal joint 4 on the outboard side and an intermediate end connected to the constant velocity universal joint 4 on the outboard side are shown. A shaft 40 and an inboard constant velocity universal joint 50 connected to the other end of the intermediate shaft 40 are provided. In this case, on the outboard side, the hub wheel 2, the rolling bearing 6, and the constant velocity universal joint 4 are integrated to form a wheel bearing device.

  The rear wheel bearing device shown in FIGS. 1 and 2 is used for the wheel bearing device. In this case, the opening on the inboard side of the outer joint member 3 is closed by the boot 34. In this case, the boot 34 includes a large diameter portion 34a, a small diameter portion 34b, and a bellows portion 34c disposed between the large diameter portion 34a and the small diameter portion 34b. The large diameter portion 34 a is attached to the outer joint member 3 via the metal adapter 33.

  Similarly to the constant velocity universal joint 4 on the outboard side, the inboard side constant velocity universal joint 50 is also an inner joint in which ball grooves 58a inclined in opposite directions with respect to the axis are alternately formed in the circumferential direction on the outer peripheral surface. A member 58, an outer joint member 69 in which ball grooves 69a inclined in opposite directions with respect to the axis are alternately formed on the inner peripheral surface, and an inner joint member 58 inclined in directions opposite to each other with respect to the axis. Between the outer peripheral surface of the inner joint member 58 and the inner peripheral surface of the outer joint member 69. The torque transmitting ball 59 incorporated at the intersection of the ball groove 58 a of the outer joint member 69 and the ball groove 69 a of the outer joint member 69. And a cage 51 for holding the torque transmission balls 59 at predetermined intervals in the circumferential direction.

  The outer joint member 69 includes a mouth portion 61 in which the ball groove 69 a is formed on the inner peripheral surface, and a shaft portion (stem portion) 62 projecting from the bottom wall of the mouth portion 61. The opening of the outer joint member 69 is closed with a boot 70. In this case, the boot 70 includes a large diameter portion 70a, a small diameter portion 70b, and a bellows portion 70c disposed between the large diameter portion 70a and the small diameter portion 70b. The large diameter portion 70 a is attached to the outer joint member 69 via the metal adapter 71.

  The constant velocity universal joint 50 in this case is a float type in which the minimum inner diameter of the cage 51 is smaller than the maximum outer diameter of the inner joint member 58. Further, a spline portion is formed on the inner peripheral surface of the center hole of the inner joint member 58, and an end spline portion of the shaft is inserted into the center hole, so that the spline portion of the inner joint member 58 and the spline portion on the shaft side Are engaged. The outer joint member 69 includes a mouth portion 61 and a stem portion 62 that is connected to the mouth portion 61.

  A reference surface 5a is formed on the outer periphery of the outer member 5 of the rolling bearing 6 and used for fitting between the vehicle body mounting flange 32 and a mating member (knuckle) to which the vehicle body mounting flange 32 is fixed. In this case, the maximum outer diameter φDb of the constant velocity universal joint 4 on the outboard side is smaller than the outer diameter φDa of the reference surface 5a and is equal to or larger than the maximum outer diameter φDc of the constant velocity universal joint 50 on the inboard side.

  As a method for assembling the drive shaft as described above, a method is employed in which the hub bearing portion on the outboard side is temporarily fixed to the knuckle after the inboard constant velocity universal joint 50 is inserted into the housing. In that case, after fixing the hub bearing portion to the knuckle, the inboard side constant velocity universal joint 50 is once slid and contracted as much as necessary, and then inserted into the differential hole as it is.

  Thus, in the drive shaft of the present invention, the hub wheel 2 having the vehicle body mounting flange 1 and the double row rolling bearing 6 are integrated on the outboard side, and the rolling bearing 6 is provided on the outer periphery of the outer joint member 4. An inner rolling surface 19 is formed. That is, on the outboard side, a so-called four-generation wheel bearing device is configured. Moreover, a reference surface 5a used for fitting with a mating member (knuckle) is formed, and the maximum outer diameter φDb of the constant velocity universal joint 4 on the outboard side is smaller than the outer diameter φDa of the reference surface 5a. Since the constant velocity universal joint 50 on the inboard side is not less than the maximum outer diameter φDc, it can be easily assembled to the vehicle (knuckle). In addition, since the slide type constant velocity universal joint is used on the outboard side and the inboard side, the outboard side constant velocity universal joint 4 and the inboard side constant velocity universal joint 50 are slid and contracted to form the stem portion. When 62 is inserted into the hole of the differential (differential), a sufficient amount of contraction can be secured. For this reason, assembly work can be performed easily and reliably.

  By using a cross groove type constant velocity universal joint as the constant velocity universal joint 4 on the outboard side, the constant velocity universal joint 4 on the outboard side can be easily stuffed, and it operates even with a negative clearance. It is difficult to decrease the nature. Thereby, the play in the circumferential direction is suppressed, and a drive shaft excellent in NVH characteristics can be provided.

  By using ten torque transmitting balls 9, the rolling bearing (bearing portion) 6 can be made compact. On the other hand, if there are six torque transmission balls, the outer diameter of the outer ring (outer joint member) 3 of the constant velocity universal joint 4 is increased, and the inner diameter of the knuckle and the bearing portion are increased.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the drive shaft according to the present invention, the inboard side constant velocity is freely adjustable. The joint 50 is not limited to the cross groove type constant velocity universal joint, and other constant velocity universal joints can be used as long as they are sliding type constant velocity universal joints. The constant velocity universal joints 4 and 50 may be non-float type in which the cage 10 and 51 have a minimum inner diameter larger than that of the inner joint members 8 and 58.

It is sectional drawing of the bearing apparatus for rear wheels which shows embodiment of this invention. It is a side view of the constant velocity universal joint of the bearing apparatus for rear wheels of the said FIG. FIG. 2 is a cross-sectional view of a drive shaft using the rear wheel bearing device of FIG. 1. It is sectional drawing of the conventional rear-wheel bearing apparatus.

Explanation of symbols

2 Hub wheel 3 Outer joint member 4, 50 Constant velocity universal joint 5 Outer member 5a Reference surface 6 Rolling bearing 8 Inner joint member 9 Transmission balls 18, 19 Inner rolling surface 20, 21 Outer rolling surface 32 Car body mounting flange 40 Intermediate shaft

Claims (5)

A rear wheel bearing device in which a hub wheel having a vehicle body mounting flange, a double row rolling bearing, and a constant velocity universal joint in which a shaft portion of an outer joint member is fitted into the hub wheel are unitized,
The double-row rolling bearing has an outer member in which a double-row outer rolling surface is formed on the inner periphery, and one inner rolling surface of the rolling bearing is formed on the outer periphery of the hub wheel, The other inner rolling surface of the rolling bearing is formed on the outer periphery of the outer joint member of the constant velocity universal joint,
The constant velocity universal joint includes an inner joint member having outer peripheral surfaces in which ball grooves inclined in opposite directions with respect to an axis are alternately formed in a circumferential direction, and ball grooves inclined in directions opposite to each other in relation to an axis. Torque transmission incorporated at the intersection of the outer joint member having inner peripheral surfaces alternately formed in the circumferential direction and the ball groove of the inner joint member and the ball groove of the outer joint member inclined in opposite directions with respect to the axis. A bearing device for a rear wheel, which is a cross groove type constant velocity universal joint including a ball.   The rear wheel bearing device according to claim 1, wherein the number of torque transmission balls of the constant velocity universal joint is ten. It has a sliding constant velocity universal joint on the outboard side, a sliding constant velocity universal joint on the inboard side, and an intermediate shaft connecting these constant velocity universal joints. A drive shaft in which a hub ring having a double row rolling bearing and a constant velocity universal joint in which a shaft portion of an outer joint member is fitted into the hub ring are unitized,
The double-row rolling bearing has an outer member in which a double-row outer rolling surface is formed on the inner periphery, and one inner rolling surface of the rolling bearing is formed on the outer periphery of the hub wheel, The other inner rolling surface of the rolling bearing is formed on the outer periphery of the outer joint member of the constant velocity universal joint, and the vehicle body mounting flange and the counterpart member on which the vehicle body mounting flange is fixed to the outer periphery of the outer member of the rolling bearing The maximum outer diameter of the constant velocity universal joint on the outboard side is smaller than the outer diameter of the reference surface and the maximum outer diameter of the constant velocity universal joint on the inboard side. A drive shaft characterized by the above.   An inner joint member having an outer peripheral surface in which ball grooves inclined in opposite directions with respect to the axis are alternately formed in the circumferential direction of the constant velocity universal joint on the outboard side and the constant velocity universal joint on the inboard side; An outer joint member having an inner peripheral surface in which ball grooves inclined in opposite directions with respect to the axis are alternately formed in a circumferential direction, and a ball groove and an outer joint of inner joint members inclined in opposite directions with respect to the axis 4. The drive shaft according to claim 3, wherein the drive shaft is a cross-groove type constant velocity universal joint including a torque transmission ball incorporated at a crossing portion of the member with the ball groove.   The drive shaft according to claim 3 or 4, wherein the number of torque transmission balls of the constant velocity universal joint is ten.

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