JP4877904B2 - Drive wheel bearing device and axle module including the same - Google Patents

Description

  The present invention relates to a drive wheel bearing device that rotatably supports a drive wheel of a vehicle such as an automobile with respect to a suspension device, and more particularly, a wheel bearing and a constant velocity universal joint are unitized, and the assembly workability to a vehicle is improved. In addition, the drive wheel bearing device and the drive shaft connected to the constant velocity universal joint of the drive wheel bearing device are improved. The present invention relates to a wheel bearing assembly (hereinafter referred to as an axle module) including a dynamic constant velocity universal joint.

  A power transmission device that transmits engine power of a vehicle such as an automobile to a wheel transmits power from the engine to the wheel, and also causes radial or axial displacement from the wheel that occurs when the vehicle bounces or turns when traveling on a rough road. For example, as shown in FIG. 4, one end of the drive shaft 100 interposed between the engine side and the drive wheel side is connected to the sliding type constant velocity universal joint 101. The other end is connected to a wheel 105 via a drive wheel bearing device 104 including a fixed type constant velocity universal joint 103.

  In such a drive wheel bearing device 104, the vehicle body mounting flange is integrated with the outer member of the double row rolling bearing from the first generation in which the double row rolling bearing (not shown) is mounted on the suspension device. Various structures have been developed up to the third-generation wheel bearings. In recent years, this drive wheel bearing device 104 tends to shift to a so-called fourth generation structure in which the wheel bearing 106 and the fixed type constant velocity universal joint 103 are unitized for further light weight and compactness. is there.

FIG. 5 is a typical example of such a fourth generation drive wheel bearing device. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outboard side (left side in the drawing), and the side closer to the center is referred to as the inboard side (right side in the drawing).
This drive wheel bearing device is configured by unitizing a hub wheel 51, a double row rolling bearing 52, and a constant velocity universal joint 53. The hub wheel 51 integrally has a wheel mounting flange 54 for mounting a wheel (not shown) at an end portion on the outboard side, and hub bolts 56 are implanted at circumferentially equidistant positions. An inner rolling surface 51a on the outboard side and a small-diameter step portion 63 extending in the axial direction from the inner rolling surface 51a are formed on the outer peripheral surface, and an uneven portion 55 is formed on the inner peripheral surface. The hardening process is given to the range of 54-64 HRC.

  The double-row rolling bearing 52 includes an outer member 57, an inner member 58, and double-row balls 59, 59. The outer member 57 integrally has a vehicle body attachment flange 57b for attaching to the knuckle N constituting the suspension device on the outer periphery, and double row outer rolling surfaces 57a, 57a are formed on the inner periphery. On the other hand, the inner member 58 refers to the hub wheel 51 and the outer joint member 64 fitted in the small diameter step portion 63 of the hub wheel 51 so as to abut on the outer ring member 64. An inner rolling surface 64a is integrally formed. Double-row balls 59 and 59 are accommodated between the rolling surfaces 57a and 51a and 57a and 64a, respectively, and are held by the cages 60 and 60 so as to be freely rollable. In addition, seals 61 and 62 are attached to the ends of the double row rolling bearing 52 to prevent leakage of lubricating grease sealed inside the bearing and intrusion of rainwater and dust from the outside into the bearing. ing.

  The constant velocity universal joint 53 includes an outer joint member 64, a joint inner ring 65, a cage 66 and a torque transmission ball 67. The outer joint member 64 has a cup-shaped mouth portion 68, a shoulder portion 69 that forms the bottom portion of the mouth portion 68, and a hollow shaft portion 70 that extends from the shoulder portion 69 in the axial direction. On the outer periphery of the shaft portion 70, a small diameter step portion 70a fitted into the small diameter step portion 63 and a fitting portion 70b extending in the axial direction from the small diameter step portion 70a are formed. Then, the shaft portion 70 of the outer joint member 64 is fitted into the hub wheel 51, and a diameter expanding jig such as a mandrel is pushed into the shaft portion 70 to increase the diameter of the fitting portion 70b. 51, the hub wheel 51 and the outer joint member 64 are integrally plastically joined.

Here, when the vehicle is assembled, the outer member 57 is fitted to the inner diameter of the knuckle N. The outer diameter of the fitting surface 57c is Da, and the maximum outer diameter of the constant velocity universal joint 53, here. When the maximum outer diameter of the boot 71 mounted on the outer periphery of the mouse portion 68 is Db, Da ≧ Db is set. As a result, as shown in FIG. 6, the pair of constant velocity universal joints 53, 72, the drive shaft 73 connected to the constant velocity universal joints 53, 72, and the pair of constant velocity universal joints 53, 72 are out. The axle module in which the constant velocity universal joint 53 on the board side and the double row rolling bearing 52 are unitized can pass through the knuckle N. Therefore, the workability of the assembly to the vehicle is further improved, and workability such as inspection and repair is improved.
JP 2001-171308 A

  In such a conventional drive wheel bearing device, the maximum outer diameter of the constant velocity universal joint 53 is usually larger than the outer diameter of the fitting surface 57 c of the outer member 57. By reviewing the internal specifications such as size and number and changing to a compact type, it is possible to make the diameter smaller than the fitting surface 57c. However, in a vehicle having a large torque transmission capacity, the size of the constant velocity universal joint inevitably increases. In this case, the size of the outer member 57 has to be increased. This increases the weight of the knuckle N as well as the outer member 57, and not only halves the effect of a light and compact device, but also requires a review of the design specifications around the brake as the knuckle N increases in size. It became. Therefore, it is not necessary to review the design specifications of the knuckle N and other undercarriage parts, or to reduce the specification change to the minimum, without reducing the torque transmission capacity, It has been a problem to reduce the diameter.

  The present invention has been made in view of such circumstances, and suppresses the maximum outer diameter of the constant velocity universal joint to improve the assembling workability to the vehicle and prevent damage to parts in disassembly / assembly. It is an object of the present invention to provide a drive wheel bearing device with stable quality and an axle module including the same.

In order to achieve the object, the invention according to claim 1 of the present invention has a vehicle body mounting flange for fastening to the knuckle on the outer periphery, and a double row outer rolling surface is formed on the inner periphery. An outer member, a hub wheel integrally having a wheel mounting flange at one end, and having one inner rolling surface facing the outer rolling surface of the double row directly formed on the outer periphery, The outer side of the constant velocity universal joint that is integrally formed with the other inner rolling surface that is fitted to the outer periphery and that faces the outer rolling surface of the double row, and a hollow shaft portion that extends in the axial direction from the inner rolling surface. A drive wheel comprising an inner member made of a joint member and a double row rolling element accommodated so as to be freely rollable between both rolling surfaces, wherein the hub wheel and the outer joint member are integrally plastically coupled. In the bearing device, a fitting surface of the outer member that is fitted into the knuckle is provided on the outer joint member. A steel plate boot adapter is fitted to the opening of the outer joint member, and the boot adapter is fitted to the outer periphery of the outer joint member; and A configuration is adopted in which a small-diameter portion extending in the axial direction from the cylindrical portion is provided, and the large-diameter side end portion of the boot is coupled along the outer diameter of the arc-shaped portion of the small-diameter portion.

Thus, in the drive wheel bearing device of the fourth generation structure, the fitting surface of the outer member fitted into the knuckle is set larger than the outer diameter of the outer joint member, and the outer joint member A steel plate boot adapter is fitted into the opening of the outer joint member, and the boot adapter includes a cylindrical portion fitted to the outer periphery of the outer joint member, and a small diameter portion extending in the axial direction from the cylindrical portion . Since the large-diameter end of the boot is joined along the outer diameter of the arcuate part, the maximum outer diameter of the constant velocity universal joint is the outer diameter of the outer joint member. The drive shaft connected to the universal joint can easily pass through the knuckle, and the boot is not easily removed from the boot adapter in the axial direction, but the large-diameter end of the boot is widened to the outer diameter side. The structure can be easily removed That. Therefore, the workability of assembling the axle module to the vehicle is further improved, and it is possible to provide a drive wheel bearing device that prevents damage to parts during disassembly and assembly and stabilizes the quality.

  Preferably, as in the invention described in claim 2, a hardened uneven portion is formed on the inner periphery of the hub wheel, and the shaft portion of the outer joint member is expanded to bite into the uneven portion and caulked. If the hub wheel and the outer joint member are integrally plastically bonded, the strength and durability of the hub wheel can be improved, the weight and size can be reduced, and the ease of incorporation into the vehicle can be simplified. it can.

  According to a third aspect of the present invention, the constant velocity universal joint is accommodated in an outer joint member and a track groove extending in the axial direction formed on the inner periphery of the outer joint member, and the outer peripheral portion has a diameter. It is composed of a tripod constant velocity universal joint including a tripod member having three leg shafts extending outwardly in the direction of the same, and a roller rotatably inserted on these leg shafts. As a result, the weight and size can be reduced, the unsprung weight can be reduced, and the operability of the vehicle can be improved.

  In addition, if the drive wheel bearing device is for a rear wheel as in the invention described in claim 4, the constant velocity universal joint may be small with respect to the steering side operating angle, and the allowable operation as in the prior art. Even if a fixed type constant velocity universal joint such as a zepper type having a large corner is not used, it can be sufficiently applied.

According to a fifth aspect of the present invention, the drive wheel bearing device according to any one of the first to fourth aspects and a drive having one end connected to the constant velocity universal joint of the drive wheel bearing device. The boot comprises a shaft and a sliding-type constant velocity universal joint connected to the other end of the drive shaft. A steel plate boot adapter is fitted into the opening of the outer joint member of the constant velocity universal joint. The adapter includes a cylindrical portion fitted to the outer periphery of the outer joint member, and a small-diameter portion extending in the axial direction from the cylindrical portion, and the large-diameter side of the boot so as to follow the outer diameter of the arc-shaped portion of the small-diameter portion. While the end portions are coupled, the fitting surface of the outer member is set to have a larger diameter than the outer diameter of the outer joint member in the constant velocity universal joint.

As a result, the maximum outer diameter of the pair of constant velocity universal joints becomes the outer diameter of the outer joint member, respectively, and the axle module can easily pass through the knuckle and the boot adapter is difficult to come off in the axial direction. However, it is possible to make the structure easy to come off by widening the large-diameter side end of the boot to the outer diameter side . Therefore, the workability of assembling to the vehicle is further improved, and it is possible to provide an axle module in which the quality is stabilized by preventing damage to parts during disassembly and assembly.

A bearing device for a drive wheel according to the present invention has an outer member integrally formed with a vehicle body mounting flange for fastening to a knuckle on an outer periphery, a double row outer rolling surface formed on an inner periphery, and one end portion. A hub wheel integrally having a wheel mounting flange and directly forming one inner rolling surface opposed to the outer rolling surface of the double row on the outer periphery, and the hub wheel fitted inside the hub wheel, and the double row on the outer periphery. An inner member made of an outer joint member of a constant velocity universal joint integrally formed with the other inner rolling surface opposite to the outer rolling surface and a hollow shaft portion extending in the axial direction from the inner rolling surface. A drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled to each other. The fitting surface of the outer member to be fitted is set to have a larger diameter than the outer diameter of the outer joint member. In addition, a steel plate boot adapter is fitted into the opening of the outer joint member, and the boot adapter is fitted into the outer periphery of the outer joint member, and a small diameter extending in an axial direction from the cylindrical portion. Since the large-diameter side end of the boot is joined along the outer diameter of the arc-shaped portion of this small-diameter portion , the maximum outer diameter of the constant velocity universal joint is the outer diameter of the outer joint member, etc. a constant velocity universal joint, Rutotomoni can drive shaft coupled to the constant velocity universal joint is easily pass through the knuckle, boots from the boot adapter yet hard structure omission axially, large-diameter end of the boot By expanding the outer part to the outer diameter side, it is possible to make the structure easy to come off, and the workability of assembling the axle module to the vehicle has been further improved. Wheel It is possible to provide a bearing device.

An axle module according to the present invention includes a drive wheel bearing device according to any one of claims 1 to 4, a drive shaft having one end connected to a constant velocity universal joint of the drive wheel bearing device, and the drive It comprises a sliding type constant velocity universal joint connected to the other end of the shaft, and a steel plate boot adapter is fitted into the opening of the outer joint member of the constant velocity universal joint. A cylindrical portion fitted to the outer periphery of the joint member, and a small-diameter portion extending in the axial direction from the cylindrical portion, and the large-diameter side end portion of the boot are coupled along the outer diameter of the arc-shaped portion of the small-diameter portion. In addition, since the fitting surface of the outer member is set to be larger than the outer diameter of the outer joint member in the constant velocity universal joint, the maximum outer diameter of the pair of constant velocity universal joints is respectively set to the outer joint. The outer diameter of the member Rutotomoni can le module to easily pass through the knuckle, boots from the boot adapter yet hard structure missing in the axial direction and to extend the larger diameter end of the boot on the outer diameter side, out easily structure and Thus, the operability of assembling to the vehicle is further improved, and it is possible to provide an axle module that stabilizes quality by preventing damage to parts during disassembly and assembly.

A body mounting flange for fastening to the knuckle on the outer periphery, an outer member having a double row outer raceway formed on the inner periphery, and a wheel mounting flange on one end are integrated on the outer periphery. One inner rolling surface facing the outer rolling surface of the double row is directly formed, and a hub wheel formed with a concave and convex portion hardened on the inner periphery, and fitted into the hub wheel, and the double row on the outer periphery. An inner member made of an outer joint member of a constant velocity universal joint integrally formed with the other inner rolling surface opposite to the outer rolling surface and a hollow shaft portion extending in the axial direction from the inner rolling surface. A double-row rolling element accommodated between the rolling surfaces so as to be freely rollable, the shaft portion fitted in the hub ring is enlarged in diameter, and is bitten into the concavo-convex portion and caulked, In the drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled, The fitting surface of the outer member is set to be larger than the outer diameter of the outer joint member, and a boot adapter made of steel plate is fitted into the opening of the outer joint member. Comprises a cylindrical portion fitted to the outer periphery of the outer joint member and a small diameter portion extending in the axial direction from the cylindrical portion, and the large diameter side end of the boot so as to follow the outer diameter of the arc-shaped portion of the small diameter portion The parts are combined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of an axle module according to the present invention, and FIG. 2 is an enlarged view of a main part of FIG.

The axle module transmits power from an engine (not shown) to the wheels, and rotatably supports the wheels with respect to the suspension device. The drive wheel bearing device 4 and the constant velocity of the drive wheel bearing device 4 are the same. A drive shaft D / S having one end connected to the universal joint 3 and a sliding type constant velocity universal joint 25 connected to the other end of the drive shaft D / S.
As shown in an enlarged view in FIG. 2, the drive wheel bearing device 4 has a configuration called a fourth generation in which the hub wheel 1, the double row rolling bearing 2 and the constant velocity universal joint 3 are unitized. Yes. The hub wheel 1 is formed of medium carbon steel containing carbon 0.40 to 0.80 wt% such as S53C, and integrally includes a wheel mounting flange 5 for mounting a wheel to an end portion on the outboard side. Hub bolts 5a are implanted at equal circumferential positions. Concave and convex portions 6 are formed on the inner peripheral surface of the hub wheel 1, and a hardened layer is formed with a surface hardness in the range of 54 to 64 HRC by heat treatment. As the heat treatment, local heating is preferable, and quenching by high-frequency induction heating that can set the hardened layer depth relatively easily is preferable.

  In addition, the concavo-convex portion 6 is formed in an iris knurl shape, and is a cross groove formed by a plurality of annular grooves formed independently by turning or the like and a plurality of axial grooves formed by broaching or the like substantially orthogonal to each other. Alternatively, it consists of a cross groove composed of spiral grooves inclined with respect to each other. Moreover, the convex part of the uneven | corrugated | grooved part 6 is formed in spire shape, such as triangular shape, in order to ensure favorable bite property.

  The double-row rolling bearing 2 includes an outer member 7, an inner member 8, and double-row rolling elements (balls) 9 and 9. The outer member 7 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and a vehicle body mounting flange 7b for mounting on a knuckle (not shown) constituting a suspension device is integrally formed on the outer periphery. And double row outer rolling surfaces 7a, 7a are formed on the inner periphery.

  On the other hand, the inner member 8 refers to the hub wheel 1 and an outer joint member 14 to be described later fitted into the small-diameter step portion 13 of the hub wheel 1 in a butted manner. , 7a is formed on the outer periphery of the hub wheel 1, and the other (inboard side) inner rolling surface 14a is formed on the outer periphery of the outer joint member 14, respectively. . And the double-row rolling elements 9 and 9 are accommodated between these rolling surfaces 7a and 1a and 7a and 14a, respectively, and are hold | maintained by the holder | retainers 10 and 10 so that rolling is possible. Further, seals 11 and 12 are attached to the end portion of the outer member 7 to prevent leakage of lubricating grease sealed inside the bearing and intrusion of rainwater or dust from the outside into the bearing. Here, as the double row rolling bearing 2, a double row angular contact ball bearing using balls as the rolling elements 9 is illustrated, but the present invention is not limited to this, and for example, a tapered roller is used for the rolling elements 9. Double row tapered roller bearings may also be used.

  The constant velocity universal joint 3 includes an outer joint member 14, a joint inner ring 15, a cage 16, and a torque transmission ball 17. The outer joint member 14 is formed of medium carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and has a cup-shaped mouth portion 18, a shoulder portion 19 that forms the bottom portion of the mouth portion 18, and the shoulder portion. And a hollow shaft portion 20 extending in the axial direction from the portion 19. On the outer periphery of the shaft portion 20, a small-diameter step portion 20a that is fitted into the small-diameter step portion 13 of the hub wheel 1 and a fitting portion 20b that extends in the axial direction from the small-diameter step portion 20a are formed. A boot adapter 23 is attached to the outer periphery of the mouth portion 18 on the opening side, a boot 21 is attached to a small diameter portion 23c of the boot adapter 23, and an end cap 22 attached to the hollow shaft portion 20 is used to Leakage of grease sealed in the portion 18 and prevention of rainwater, dust, etc. from entering the joint from the outside are prevented.

  In addition, eight curved track grooves 18 a extending in the axial direction are formed on the inner periphery of the mouse portion 18, and eight track grooves 15 a facing the track grooves 18 a are formed on the outer periphery of the joint inner ring 15. Has been. A torque transmitting ball 17 is accommodated between the track grooves 18a and 15a and is held by the cage 16 so as to be able to roll. In the outer joint member 14, a predetermined hardened layer is formed by induction hardening or the like over at least the track groove 18 a and the shoulder portion 19 to the small diameter step portion 20 a of the shaft portion 20. In addition, the fitting part 20b of the axial part 20 is made into the hardness after forging.

  Here, the compact type constant velocity universal joint 3 having eight balls is illustrated, but the present invention is not limited to this, and a general constant velocity universal joint composed of six balls may be used. Furthermore, the constant velocity universal joint 3 may be a fixed type, and the track grooves 15a and 18a are not limited to the illustrated curved shape, and although not shown, a so-called underscore formed by a track groove having a part of a straight line. A cut-free type constant velocity universal joint may be used.

  The hub wheel 1 and the outer joint member 14 are joined by plastic joining. That is, the shaft portion 20 of the outer joint member 14 is fitted into the hub wheel 1, and the fitting portion 20 b is expanded by pushing a diameter expanding jig such as a mandrel into the hollow shaft portion 20. The hub wheel 1 and the outer joint member 14 are integrally plastically bonded by biting into the uneven portion 5 of the hub wheel 1 and caulking. As a result, it is not necessary to control the preload by tightening firmly with a nut or the like as in the prior art, so that the weight and size can be reduced and the strength and durability of the hub wheel 1 can be improved and long. The amount of preload can be maintained for a period. Furthermore, it has the feature that it can be easily incorporated into a vehicle.

  The hub wheel 1 is hardened by induction hardening on the surfaces of the seal land, the inner rolling surface 1a, and the small diameter step 13 where the seal lip of the seal 11 on the outboard side slides. Moreover, the fitting part 20b to be expanded is an unquenched part having a surface hardness of 24 HRC or less after forging, and the hardness difference between the surface hardness 54 to 64 HRC of the uneven part 6 of the hub wheel 1 is set to 30 HRC or more. It is preferable to do this. Thereby, the fitting part 20b can bite into the uneven part 6 easily and deeply, and both can be firmly plastically bonded without the tip of the uneven part 6 being crushed.

  Note that the coupling between the hub wheel 1 and the outer joint member 14 is not limited to such a diameter-enlarged caulking type plastic coupling. For example, although not illustrated, the shaft portion of the outer joint member is fitted inside the hub wheel, and this shaft A so-called swing caulking type in which the end of the portion is plastically deformed radially outward and is crimped to the end of the hub wheel may be used.

  Here, the boot 21 is attached to the opening of the mouth portion 18 of the outer joint member 14 via the boot adapter 23. The boot adapter 23 is formed in a cup shape by press working from a corrosion-resistant steel plate such as a stainless steel plate, and has a cylindrical portion 23a that is externally fitted to the mouth portion 18, and a flange portion 23b that extends radially inward from the cylindrical portion 23a. And a small-diameter portion 23 c that accommodates the large-diameter side end portion of the boot 21. The boot adapter 23 is fixed by caulking the tip of the cylindrical portion 23 a in an annular groove formed in the mouse portion 18 in a state where the collar portion 23 b is in contact with the end face of the mouse portion 18 and positioned. An elastic ring 24 is interposed between the cylindrical portion 23a and the mouse portion 18 to prevent rainwater or the like from entering the boot 21 from the cylindrical portion 23a. In the present embodiment, the boot adapter 23 is fitted into the opening of the mouse portion 18, and the large-diameter side end of the boot 21 is coupled to the small-diameter portion 23 c of the boot adapter 23. The maximum outer diameter D1 is the outer diameter of the outer joint member 14.

  On the other hand, the constant velocity universal joint 25 on the inboard side is, as shown in FIG. 1, a tripod in which an outer joint member 26 and three leg shafts 27 a extending radially outward at the outer peripheral portion are provided in a uniform manner. A tripod type constant velocity universal joint 25 is configured by including a member 27 and a roller 29 rotatably inserted on the leg shafts 27a via needle rollers 28. The outer joint member 26 includes a cylindrical outer tube portion 30, a shoulder portion 31 that forms the bottom of the outer tube portion 30, and a shaft portion 32 that extends from the shoulder portion 31 in the axial direction. A serration (or spline) 32 a that is inserted into a differential (not shown) is formed on the outer periphery of the shaft portion 32.

  Three linear track grooves 30a extending in the axial direction are formed on the inner periphery of the outer cylindrical portion 30, and the roller 29 rolls on the track grooves 30a. Similarly to the above-described constant velocity universal joint 3 on the outboard side, a boot adapter 23 ′ is attached to the opening of the outer cylinder portion 30, and a boot 33 made of synthetic rubber or the like is interposed through the boot adapter 23 ′. Leakage of grease attached and sealed in the outer cylinder part 30 and preventing rainwater, dust and the like from entering the joint from the outside are prevented. In this embodiment, since the boot 33 is attached to the outer cylinder part 30 via the boot adapter 23 ′, the maximum outer diameter D 2 of the constant velocity universal joint 25 is the outer diameter of the outer joint member 26. Here, the tripod type is illustrated as the constant velocity universal joint 25, but the invention is not limited to this, and a sliding type constant velocity universal joint may be used. For example, a tripod type having another structure, for example, a double using a ball. An offset type constant velocity universal joint (DOJ) may be used. Moreover, the outer cylinder part 30 is not restricted to a cylindrical shape, For example, the outer periphery may be formed in the petal shape corresponding to the track groove 30a.

  When the vehicle is assembled, the outer member 7 is fitted into the knuckle N. The outer diameter of the fitting surface 7c is D3, and the maximum outer diameter of the constant velocity universal joints 3 and 25, in this case, on the outboard side, etc. The outer diameter D1 of the outer joint member 14 in the speed universal joint 3 is set, and D3 ≧ D1 ≧ D2. As a result, the axle module including the pair of constant velocity universal joints 3 and 25 and the drive shaft D / S connected to the constant velocity universal joints 3 and 25 can easily pass through the knuckle. Therefore, the workability of assembling the axle module to the vehicle is further improved, and it is possible to provide a drive wheel bearing device that prevents damage to parts during disassembly and assembly and stabilizes the quality.

  In this embodiment, in the pair of constant velocity universal joints 3 and 25 constituting the axle module, the boots 21 and 33 are mounted via the boot adapters 23 and 23 ', respectively. The operating angle is smaller than Therefore, when the allowable operating angle is insufficient, for example, the use location is limited to a portion where the operating angle is small, such as the rear wheel of an FR (front engine, rear drive) vehicle or the rear wheel of a 4WD (all wheel drive) vehicle. It is preferable to do this.

  FIG. 3 is an enlarged view of an essential part showing a second embodiment of the axle module according to the present invention. In this embodiment, the axle module according to the present invention is applied to the rear wheel side, and the same parts and portions having the same functions as those of the first embodiment described above are denoted by the same reference numerals. Detailed description is omitted.

  The rear wheel axle module transmits power from an engine (not shown) to the rear wheel and rotatably supports the rear wheel of the automobile with respect to the suspension device. The basic configuration of the rear wheel axle module includes a drive wheel bearing device 35 in which the hub wheel 1, the double row rolling bearing 2 ′ and the constant velocity universal joint 34 are unitized, and a constant velocity universal joint 34. Are connected to a drive shaft D / S, and an in-board constant velocity universal joint (not shown) connected to the other end of the drive shaft D / S.

  The double-row rolling bearing 2 ′ includes an outer member 7, an inner member 8 ′, and double-row rolling elements 9 and 9. The inner member 8 ′ refers to the hub wheel 1 and an outer joint member 36 to be described later that is fitted into the small-diameter step portion 13 of the hub wheel 1 in a butted state.

  The constant velocity universal joint 34 includes an outer joint member 36, a tripod member 37 having three leg shafts 37a extending radially outward at the outer peripheral portion, and needle rollers on the leg shafts 37a. A tripod type constant velocity universal joint 34 is configured with a roller 39 rotatably inserted through a roller 38. The outer joint member 36 includes a cylindrical outer tube portion 40, a shoulder portion 41 that forms the bottom of the outer tube portion 40, and a hollow shaft portion 42 that extends from the shoulder portion 41 in the axial direction. On the outer periphery of the shaft portion 42, a small-diameter step portion 42a fitted into the small-diameter step portion 13 of the hub wheel 1 and a fitting portion 42b extending in the axial direction from the small-diameter step portion 42a are formed.

  Three linear track grooves 40a extending in the axial direction are formed on the inner periphery of the outer cylindrical portion 40, and the roller 39 rolls on the track grooves 40a. In addition, a boot adapter 43 is attached to the opening of the outer cylinder portion 40, and a boot 44 made of synthetic rubber or the like is attached via the boot adapter 43, and leakage of grease sealed in the outer cylinder portion 40 is prevented. This prevents rainwater and dust from entering the joint from the outside.

  The boot adapter 43 is formed in a cup shape by press working from a corrosion-resistant steel plate such as a stainless steel plate, and a cylindrical portion 43a that is externally fitted to the outer cylindrical portion 40, and a flange portion 43b that extends radially inward from the cylindrical portion 43a. And a small-diameter portion 43 c that accommodates the large-diameter side end portion of the boot 44. The boot adapter 43 is fixed by caulking the tip of the cylindrical portion 43a in an annular groove formed in the outer cylindrical portion 40 in a state where the collar portion 43b is positioned in contact with the end surface of the outer cylindrical portion 40. Here, the tripod member 37 is prevented from falling off the track groove 40a by projecting a part of the flange portion 43b into the track groove 40a. An elastic ring 24 is interposed between the cylindrical portion 43a and the outer cylindrical portion 40 to prevent rainwater or the like from entering the boot 44 from the cylindrical portion 43a.

  In the present embodiment, the boot adapter 43 is fitted to the outer cylinder portion 40, and the large diameter side end portion of the boot 44 is coupled to the small diameter portion 43c of the boot adapter 43. The diameter D4 is the outer diameter of the outer joint member 36. Here, the tripod type is exemplified for the constant velocity universal joint 34, but the present invention is not limited to this, and a sliding type constant velocity universal joint may be used. For example, a tripod type having another structure, for example, a double using a ball. An offset type constant velocity universal joint (DOJ) may be used. Moreover, the outer cylinder part 40 is not restricted to a cylindrical shape, For example, the outer periphery may be formed in the petal shape corresponding to the track groove 40a.

  When the vehicle is assembled, the outer member 7 is fitted into a knuckle (not shown). The outer diameter of the fitting surface 7c is D3, and the maximum outer diameter of the constant velocity universal joint 34, here, the outer joint member. The outer diameter D4 is 36, and D3 ≧ D4 is set. Thereby, the constant velocity universal joint 34 and the drive shaft D / S connected to the constant velocity universal joint 34 can easily pass through the knuckle. Therefore, the workability of the assembly to the vehicle is further improved, and workability such as inspection and repair is improved.

  In this embodiment, since the boot 44 is attached to the outer joint member 36 via the boot adapter 43 in the constant velocity universal joint 34 constituting the axle module, the operating angle becomes small. However, for example, in a rear wheel axle module that does not involve steering, such as the rear wheel side of an FR vehicle, the operating angle of the constant velocity universal joint 34 on the outboard side is a 4WS (four wheel steering) vehicle. However, it may be as small as 23 ° at all with respect to 46-50 ° on the steering side (front wheel). Therefore, this kind of sliding type constant velocity universal joint 34 such as tripod type can be sufficiently applied without using a fixed type constant velocity universal joint such as a zepper type having a large allowable operating angle as in the prior art. In addition to being light and compact, it is possible to reduce the unsprung weight and improve the vehicle operability.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  An axle module according to the present invention includes a drive shaft constituting a power transmission device for an automobile, a pair of constant velocity universal joints connected thereto, and a four generation structure connected to the constant velocity universal joint on the outboard side. The present invention can be applied to an axle module provided with a drive wheel bearing device.

1 is a longitudinal sectional view showing a first embodiment of an axle module according to the present invention. It is a principal part enlarged view which shows the bearing apparatus for drive wheels of FIG. It is a principal part enlarged view which shows 2nd Embodiment of the axle module which concerns on this invention. It is a longitudinal cross-sectional view which shows an example of the power transmission device incorporating the bearing apparatus for drive wheels. It is a longitudinal cross-sectional view which shows the conventional bearing apparatus for drive wheels. It is explanatory drawing which shows the state which inserts an axle module in a knuckle.

Explanation of symbols

1 ················ Hub wheel 1a, 14a ··············· Inner rolling surface 2, 2 ' .... Double-row rolling bearings 3, 25, 34 ... Constant velocity universal joints 4, 35 ... ... Drive wheel bearing device 5・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 5a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub bolt 6 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... Uneven portion 7 ··············· Outside member 7a ·········· Outside rolling surface 7b ..... Body mounting flange 8, 8 '..... Inner member 9 ...・ Rolling element 10 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Retainer 11, 12 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal 13 20a, 42a ······ Small diameter step portion 14, 26, 36 ······························ 18a, 30a, 40a ··· Track groove 16 ················· 17 ·············· Mouse portion 19, 31, 41 ········· shoulder portion 20, 32, 42 ········ Shaft portion 20b, 42b ··· ·········· Fitting parts 21, 33, 44 ······················································ End caps 23, 23 ', 43 ... Boot adapters 23a, 43a ... Cylindrical parts 23b, 43b ... Knee parts 23c, 43c ... ···small Part 24 ... elastic rings 27, 37 ... tripod members 27a, 37a ... legs Shafts 28, 38 ......... Needle rollers 29, 39 ......... Rollers 30, 40 ... Outer cylinder part 32a ... Serration 51 ... Hub wheels 51a, 64a ... Inner rolling surface 52 ... Double row rolling bearing 53 ... Constant velocity universal joint 54 ...・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 55 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Uneven portion 56 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Hub bolt 57 ..... External member 57a ... ··········· Outside rolling surface 57b Interfacing surface 58 ... Inner member 59 ... Ball 60 ...・ ・ ・ ・ Retainer 61, 62 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal 63, 70a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter step 64 ... outer joint member 65 ... joint inner ring 66 ... cage 67 ...・ ・ ・ ・ ・ ・ ・ ・ ・ Torque transmission ball 68 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mouse part 69 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Shoulder 70 ・············· Shaft portion 70b ········································ ···················· Boot 72 ·························································· 101 ······································································································ Differential 103・ ・ ・ Fixed constant velocity universal joint 104 ・ ・ ・ ・ ・ ・ ・ ・ ・ Drive wheel bearing device 105 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel 106 ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel bearings D1, D2, D4, Db ・ ・ ・ ・ ・ ・ Maximum outer diameter of constant velocity universal joints D3, Da ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outside Outer diameter D / S of the mating surface of the side member ..... Drive shaft N ..... Knuckle

Claims (5)

An outer member integrally having a vehicle body mounting flange for fastening to a knuckle on the outer periphery, and a double row outer rolling surface formed on the inner periphery;
A hub wheel having a wheel mounting flange integrally at one end, and a hub ring in which one inner rolling surface facing the outer rolling surface of the double row is formed directly on the outer periphery, and the hub wheel is internally fitted to the outer periphery. An inner joint member of a constant velocity universal joint formed integrally with the other inner rolling surface facing the outer rolling surface of the double row and a hollow shaft portion extending in the axial direction from the inner rolling surface. Direction member,
A double row rolling element housed between the rolling surfaces so as to roll freely,
In the drive wheel bearing device in which the hub wheel and the outer joint member are integrally plastically coupled,
The fitting surface of the outer member fitted into the knuckle is set to have a larger diameter than the outer diameter of the outer joint member,
A steel plate boot adapter is fitted into the opening of the outer joint member, and the boot adapter includes a cylindrical portion fitted to the outer periphery of the outer joint member, and a small diameter portion extending in the axial direction from the cylindrical portion. A large-diameter side end portion of the boot is coupled along the outer diameter of the arc-shaped portion of the small-diameter portion.   A hardened concave and convex portion is formed on the inner periphery of the hub wheel, the shaft portion of the outer joint member is expanded in diameter, and is bitten into the concave and convex portion to be caulked, and the hub wheel and the outer joint member are integrally plastically bonded. The bearing apparatus for drive wheels of Claim 1 currently used.   The constant velocity universal joint is housed in an outer joint member and a track groove extending in the axial direction formed on the inner periphery of the outer joint member, and three leg shafts extending radially outward are equally distributed on the outer peripheral portion. The drive wheel bearing according to claim 1 or 2, comprising a tripod type constant velocity universal joint provided with a tripod member projecting from the roller and a roller rotatably mounted on these leg shafts. apparatus.   4. The drive wheel bearing device according to claim 1, wherein the drive wheel bearing device is used for a rear wheel. 5. The drive wheel bearing device according to claim 1, a drive shaft having one end connected to a constant velocity universal joint of the drive wheel bearing device, and a slide connected to the other end of the drive shaft. A cylindrical adapter in which a steel plate boot adapter is fitted into the opening of the outer joint member of the constant velocity universal joint, and the boot adapter is fitted to the outer periphery of the outer joint member. And a small-diameter portion extending in the axial direction from the cylindrical portion, and the large-diameter side end portion of the boot is coupled along the outer diameter of the arc-shaped portion of the small-diameter portion, and the outer member is fitted The axle module is characterized in that the surface is set to have a larger diameter than the outer diameter of the outer joint member in the pair of constant velocity universal joints.

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