JP2007139073A - Wheel bearing device and its assembling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing device assembled by using an automatic machine to reduce the number of assembling man-hours, and to provide its assembling method. <P>SOLUTION: A method is provided for assembling the wheel bearing device which has a hardened irregular portion 15 formed on the inner diameter of a hub ring 1 and a cylindrical portion 10 bitten into the irregular portion 15 with its fitting portion 10b diameter-enlarged to plastically join the hub ring 1 integrally with an inner ring member 7. Herein, a tapered roller 6 is held by a cage 12 and fitted into an outside rolling surface 4a on the outer side of an outward member 4, and then a seal 14 is pressed into the outer end of the outward member 4, reversed and fitted into the hub ring 1 vertically arranged. While the tapered roller 6 in the state of being held on an inside rolling surface 7a by the cage 13 is fitted into the outside rolling surface 4a on the inner side, the cylindrical portion 10 is internally fitted into the hub ring 1. Finally, the seal 14 is mounted between the outward member 4 and the inner ring member 7 and an inward member 5 is plastically joined to the outward member 4 being in rotating motion relative to the hub ring 1 by caulking the enlarged diameter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wheel bearing device constituted by a double row rolling bearing having a tapered roller bearing which rotatably supports a wheel of an automobile or the like, and an assembling method thereof.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like supports a hub wheel for mounting a wheel rotatably via a double row rolling bearing, and includes a drive wheel and a driven wheel. Further, this wheel bearing device has a structure called a first generation in which a wheel bearing comprising a double-row angular ball bearing or the like is fitted between a knuckle and a hub wheel constituting a suspension device. A second generation structure in which a vehicle body mounting flange or a wheel mounting flange is directly formed on the outer periphery of the side member, a third generation structure in which one inner rolling surface is directly formed on the outer periphery of the hub wheel, or a hub wheel It is roughly classified into a fourth generation structure in which the inner rolling surface is directly formed on the outer periphery of the outer joint member of the constant velocity universal joint.

  2. Description of the Related Art In recent years, wheel bearing devices that rotatably support a wheel with respect to a suspension device of an automobile have been made lighter and more compact for improving fuel efficiency. In particular, drive wheel bearing devices such as rear wheels of FR vehicles, front wheels of FF vehicles, or all wheels of 4WD vehicles are equipped with hub wheels in order to increase rigidity for steering stability. There is a tendency to unitize the bearing portion and the constant velocity universal joint. As such a wheel bearing device, the present applicant has already proposed a wheel bearing device as shown in FIG.

  This wheel bearing device comprises a hub wheel 51, a double row rolling bearing 52, and a constant velocity universal joint 53 as a unit. The double-row rolling bearing 52 includes an outer member 54, an inner member 55, and a double-row ball 56 accommodated between the two members. The inner member 55 includes a hub ring 51 and a cylindrical inner ring member 57.

  The hub wheel 51 integrally has a wheel mounting flange 58 for mounting a wheel (not shown) at one end, an inner rolling surface 51a on the outer periphery, and a cylindrical shape extending in the axial direction from the inner rolling surface 51a. A small-diameter step portion 51b is formed, and an uneven portion 59 cured by heat treatment is formed on the inner periphery.

  On the other hand, the inner ring member 57 has an inner rolling surface 57a formed on the outer periphery, and a cylindrical portion 60 and a connecting portion 61 are integrally projected on both sides of the inner rolling surface 57a. The cylindrical portion 60 is formed with an in-row portion 60 a fitted into the small diameter step portion 51 b of the hub wheel 51 and a fitting portion 60 b engaged with the concavo-convex portion 59. Further, a male spline (or serration) 61a is formed on the outer periphery of the connecting portion 61, and engages with a female spline (or serration) 69a formed on the inner periphery of a shoulder portion 69 of an outer joint member 64 described later. An annular groove 61b is formed at the end of the male spline 61a.

  The outer member 54 integrally has a vehicle body mounting flange 54b for mounting on a knuckle (not shown) constituting a suspension device on the outer periphery, and has a double row facing the inner rolling surfaces 51a and 57a on the inner periphery. Outer rolling surfaces 54a and 54a are formed. Seals 62 and 63 are attached to both ends of the outer member 54 to prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater and dust from the outside into the bearing.

  The hub ring 51 and the inner ring member 57 are first coupled to the cylindrical portion 60 of the inner ring member 57 until the end surface of the small-diameter stepped portion 51b of the hub ring 51 is brought into contact with the shoulder 57b of the inner ring member 57 and is brought into a butted state. The hub wheel 51 is externally fitted. Then, a diameter expanding jig (not shown) such as a punch is press-fitted into the inner diameter of the fitting portion 60b, the fitting portion 60b is enlarged in the uneven portion 59, and the hub wheel 51 and the inner ring member 57 are engaged. It is integrally plastically connected.

  The constant velocity universal joint 53 includes an outer joint member 64, a joint inner ring 65, a torque transmission ball 66 and a cage 67. The outer joint member 64 has a hollow shape, and includes a cup-shaped mouth portion 68 and a shoulder portion 69 having a smaller diameter than the mouth portion 68. A boot 71 is fixed to the open end of the mouse portion 68 and the half shaft 70 by boot bands 71a and 71b to prevent leakage of lubricating grease sealed inside the joint and intrusion of rainwater or dust from the outside. Yes.

A female spline 69 a is formed on the inner periphery of the shoulder 69 of the outer joint member 64, and is engaged with the male spline 61 a of the connecting portion 61 in the inner ring member 57. Then, the clip 72 mounted in the annular groove 61b of the male spline 61a is engaged with the raised portion of the female spline 69a, and the inner ring member 57 and the outer joint member 64 are integrally coupled so as to be separable in the axial direction. As a result, the bearing and the constant velocity universal joint can be separably fixed with one touch with a simple configuration, and some defective parts can be replaced instead of replacing the unit during repair inspection in the market. it can.
JP 2003-112502 A

  In such a wheel bearing device, the hub wheel 51, the double-row rolling bearing 52, and the constant velocity universal joint 53 are unitized to reduce weight and size, and the constant velocity universal joint 53 is fixed in a separable manner. Features to improve repairability. However, the wheel bearing device constituted by such a double row angular ball bearing has been developed not only in the third generation but also in the fourth generation, but the wheel bearing constituted by a double row conical roller bearing. Since the device is used for an off-road car, a truck or the like with a heavy vehicle body, there is little need for downsizing and the development is not progressing.

  Furthermore, the following problems can be cited as the reason why development of a wheel bearing device composed of double row tapered roller bearings is not progressing. This is due to the difference in assembly between the angular ball bearing and the tapered roller. One of the types of the second generation tapered roller type is to assemble the inner ring, cage, and tapered roller into sub-units and use them as outer members. Although it is possible to assemble, in the third generation, a hub wheel having a wheel mounting flange and an inner raceway surface formed directly on the outer periphery, and an inner ring or an inner ring member fitted to the hub wheel are removed from the rear. It is necessary to assemble to the side member. Therefore, if the cage is not configured to hold the tapered roller while being held, the tapered roller is dropped from the cage in the assembling process, causing a problem in assembly by the automatic machine.

  The other is that when the bearings are assembled, the tapered rollers rub against each other in the direction of the generatrix of the rolling surfaces. The coefficient of friction of the contact portion increases. For this reason, there is a possibility that the tapered rollers do not move smoothly in a large bowl and are assembled in an unaligned state. In this case, even when the internal clearance should be negative, it becomes a positive internal clearance, and there is a possibility that the desired preload cannot be applied accurately. In particular, when a so-called skew occurs in which the central axis of the tapered roller is inclined with respect to the normal rotation axis, such a problem becomes more remarkable. In addition, when it becomes the fourth generation structure in which the rolling surface is directly formed on the outer periphery of the outer joint member constituting the constant velocity universal joint, it is more difficult to assemble with an automatic machine.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a wheel bearing device and an assembling method thereof capable of reducing the number of assembling steps by assembling with an automatic machine and accurately setting a preload. It is said.

  In order to achieve such an object, the invention according to claim 1 of the present invention has a vehicle body mounting flange integrally attached to the suspension on the outer periphery, and a double row outer rolling surface is formed on the inner periphery. An outer member and a wheel mounting flange for attaching a wheel to one end of the outer member, and one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and from this inner rolling surface A hub wheel formed with a small-diameter step portion extending in the axial direction, and the other inner rolling surface that is fitted to the hub wheel and that faces the outer rolling surface of the double row is formed on the outer periphery. An inner member formed of an outer ring member of an inner ring member or a constant velocity universal joint in which a cylindrical portion extending in the axial direction from the rolling surface is formed, and a cage between both rolling surfaces of the inner member and the outer member Double row rolling elements accommodated to be freely rollable via the outer member and the inner member And a seal attached to the opening of the annular space formed by forming an uneven portion hardened on the inner diameter of the hub wheel, and expanding the fitting portion formed at the end of the cylindrical portion. In the wheel bearing device in which the hub wheel and the inner ring member or the outer joint member are integrally plastically coupled by biting into the uneven portion, at least the inner side rolling element of the double row rolling elements is a tapered roller. And a large collar for guiding the tapered roller is formed on the large diameter side of the inner rolling surface.

  Thus, the outer member having a double row outer rolling surface formed on the inner periphery, and the wheel mounting flange integrally formed at one end and the outer side facing the double row outer rolling surface on the outer periphery. A hub wheel with an inner rolling surface formed directly, an inner rolling surface on the inner side facing the outer rolling surface of the double row on the outer periphery, and a cylindrical portion extending in the axial direction from the inner rolling surface were formed. In an opening of an annular space formed by an inner member composed of an inner ring member or an outer joint member, a double row rolling element accommodated between the two members, and an outer member and an inner member. A hardened concave and convex portion is formed on the inner diameter of the hub wheel, and the fitting portion formed at the end of the cylindrical portion is enlarged to bite into the concave and convex portion. In a wheel bearing device in which an inner ring member or an outer joint member is integrally plastically coupled, a double row rolling element Among them, at least the inner side rolling element is composed of tapered rollers, and a large collar for guiding the tapered rollers is formed on the large diameter side of the inner rolling surface. It is possible to provide a wheel bearing device in which the load capacity or rigidity of the bearing row is increased.

  According to a second aspect of the present invention, the inner member includes the hub ring and an inner ring member fitted into the hub ring, and a cylindrical connecting portion is provided on the inner side of the inner ring member. If the inner ring member is coupled to the outer joint member through the serration so as to be able to transmit torque and be separable, some of the defective parts are not replaced at the time of repair and inspection in the market. Parts can be replaced.

  According to a third aspect of the present invention, the retainer is formed of synthetic resin by injection molding, and at least the outer retainer is configured to be able to hold the rolling elements in a pocket in a drop-off prevention state. If this is the case, it is possible to reliably prevent the rolling element from being held by the outer rolling surface of the outer member and the retainer and falling off from the retainer. Significant reductions can be made.

  According to a fourth aspect of the present invention, there is provided a method invention according to claim 4, wherein a vehicle body mounting flange for being attached to a suspension device is integrally provided on the outer periphery, and an outer rolling surface having double rows is formed on the inner periphery. A member, and a wheel mounting flange for mounting the wheel at one end, and an outer side inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and an axial direction from the inner rolling surface A hub ring formed with a small-diameter step portion extending to the inner ring, and an inner side inner rolling surface facing the outer side rolling surface of the double row is formed on the outer periphery of the hub wheel. An inner member formed of an outer ring member of an inner ring member or a constant velocity universal joint formed with a cylindrical portion extending in the axial direction from the running surface, and a cage between both rolling surfaces of the inner member and the outer member. A double row rolling element accommodated in a freely rolling manner, and the outer member and the inner part And a seal attached to the opening of the annular space formed, and a hardened uneven portion is formed on the inner diameter of the hub wheel, and the fitting portion formed at the end of the cylindrical portion is expanded in diameter. In the assembling method of the wheel bearing device in which the hub wheel and the inner ring member or the outer joint member are integrally plastically joined by biting into the uneven portion, the rolling element is held by the outer cage. The outer member is inserted into the outer outer rolling surface of the outer member placed vertically, and then the outer seal is press-fitted into the outer end of the outer member, and the outer member Is inserted into the hub wheel placed vertically and the tapered roller is held on the inner rolling surface by the inner-side retainer, and is attached to the outer rolling surface on the inner side. The cylindrical portion is inserted into the cylinder while being inserted. The inner side seal is attached to an annular space formed by the outer member and the inner member, and the outer member is rotated or shaken with respect to the hub wheel. Since the inner member is plastically connected by expanding and crimping while moving, the tapered rollers move smoothly on each rolling surface and are stably aligned in a large size, giving a predetermined preload with high accuracy. can do. By adopting such an assembling method, assembly by an automatic machine becomes possible, and the number of assembling steps can be reduced.

  According to a fifth aspect of the present invention, a motor that rotationally drives the outer member, a torque detector that detects the rotational torque of the motor, and a predetermined value that sets the detected rotational torque in advance. A preload monitoring device including a determination device for comparison, and measuring the rotational torque of the outer member to detect the presence or absence of an abnormality during assembly, and converting the preload amount using the rotational torque as a medium, Since the predetermined bearing preload amount is set, the bearing preload amount can be accurately and stably measured and managed.

  A wheel bearing device according to the present invention has a vehicle body mounting flange integrally attached to a suspension device on an outer periphery, an outer member having a double row outer rolling surface formed on an inner periphery, and one end portion. A wheel mounting flange for mounting a wheel is integrally formed, and one inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and a small diameter step portion extending in the axial direction from the inner rolling surface is formed. And the other inner rolling surface that is fitted to the hub wheel and that opposes the outer rolling surface of the double row, and that extends in the axial direction from the inner rolling surface. An inner member formed of an inner ring member formed with a portion or an outer joint member of a constant velocity universal joint, and a roll is accommodated between the rolling surfaces of the inner member and the outer member via a cage. An annular space formed by the double row rolling elements and the outer member and the inner member. And a hardened concave and convex portion formed on the inner diameter of the hub wheel, and the fitting portion formed at the end of the cylindrical portion is expanded to bite into the concave and convex portion. In the wheel bearing device in which the hub wheel and the inner ring member or the outer joint member are integrally plastically coupled, at least the inner side rolling element of the double row rolling elements is constituted by a tapered roller, and the inner side Provided wheel bearing device with increased load capacity or rigidity of double-row bearing rows while being lighter and more compact, since a large collar for guiding the tapered rollers is formed on the larger diameter side of the rolling surface can do.

  A wheel bearing device assembly method according to the present invention is the wheel bearing device assembly method according to any one of claims 1 to 3, wherein the rolling element is held by the outer cage, and the wheel bearing device is placed vertically. The outer member is inserted into the outer outer rolling surface of the outer member, and then the outer seal is press-fitted into the outer end of the outer member, and the outer member is inverted. The tapered roller is inserted and inserted into the outer side rolling surface on the inner side in a state where the tapered roller is held on the inner side rolling surface by the inner side cage. The cylindrical portion is fitted into the hub wheel, and finally, the inner side seal is mounted in an annular space formed by the outer member and the inner member, and the hub ring is attached to the hub wheel. Diameter expansion caulking while rotating or swinging the outer member Since more said inner member is plastically bonded, it can be tapered rollers to move the respective rolling surfaces on smoothly aligned stably in large rib, accurately apply a predetermined preload. By adopting such an assembling method, assembly by an automatic machine becomes possible, and the number of assembling steps can be reduced.

  An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, and formed with a tapered double row outer rolling surface opened outward on the inner periphery, and a wheel on one end A wheel mounting flange for integrally mounting, a tapered outer-side inner rolling surface facing the double-row outer rolling surface on the outer periphery, and a small-diameter step extending in the axial direction from the inner rolling surface And a tapered inner inner rolling surface that is fitted to the hub wheel and that faces the double row outer rolling surface is formed on the outer periphery. An inner member formed of an inner ring member formed with a cylindrical portion extending in the axial direction from the surface, and a plurality of rolls accommodated between the rolling surfaces of the inner member and the outer member via a cage. An annular space formed by a row of tapered rollers, the outer member and the inner member And a hardened uneven portion formed on the inner diameter of the hub wheel, and a fitting portion formed at an end of the cylindrical portion is enlarged to bite into the uneven portion. Thus, in the method of assembling the wheel bearing device in which the hub wheel and the inner ring member are integrally plastically coupled, the outer roller of the outer member, which is held vertically and held by the outer cage, The outer ring is inserted into the outer rolling surface of the outer member, and then the outer seal is press-fitted into the outer end of the outer member, and the outer member is inverted and placed vertically. In the state where the tapered roller is held on the inner rolling surface by the inner side retainer, the cylindrical portion is fitted to the hub ring while being inserted into the inner side outer rolling surface. Fitted inside, and finally with the outer member Together with the seal of the inner side into the annular space formed by the member is mounted, the inner member is plastically coupled by the said outer diameter caulked while the member is rotational movement relative to the hub wheel.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention, and FIGS. 2A to 2C are explanatory views showing an assembly method of the wheel bearing device of FIG. FIG. 3 is an explanatory view showing a diameter expansion caulking process of the wheel bearing device of FIG. 1. In the following description, the side closer to the outer side of the vehicle in a state assembled to the vehicle is referred to as the outer side (left side in the drawing), and the side closer to the center is referred to as the inner side (right side in the drawing).

  In this wheel bearing device, the hub wheel 1 and the double-row rolling bearing 2 are formed into subunits, and are unitized so as to be separable from the constant velocity universal joint 3. The double-row rolling bearing 2 includes an outer member 4, an inner member 5, and double-row tapered rollers 6 and 6. The outer member 4 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and integrally has a vehicle body mounting flange 4b for mounting to a vehicle body (not shown) on the outer periphery. The outer side rolling surfaces 4a and 4a of the taper-like double row opened outward are formed, and the surface hardness is hardened in the range of 58 to 64 HRC by induction hardening.

  On the other hand, the inner member 5 includes a hub wheel 1 and a cylindrical inner ring member 7 fitted inside the hub wheel 1. The hub wheel 1 is made of medium carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and has a wheel mounting flange 8 for mounting a wheel to an end portion on the outer side. A plurality of hub bolts 8a are planted at equal intervals in the circumferential direction. Further, on the outer periphery of the hub wheel 1, one inner (outer side) tapered inner rolling surface 1a facing the double row outer rolling surfaces 4a and 4a, and the larger diameter side of the inner rolling surface 1a A large collar 1c for guiding the tapered roller 6 is formed. Further, on the small-diameter side of the inner rolling surface 1a, a small flange for preventing the tapered roller 6 from dropping off is not formed, and a cylindrical small-diameter step portion 1b extending in the axial direction from the small-diameter side end is formed. . Then, the hardened layer has a surface hardness in the range of 58 to 64 HRC by induction hardening from the base portion 8b of the wheel mounting flange 8 to which an outer seal 14 described later is fitted to the inner rolling surface 1a and the small diameter step portion 1b. Is formed. Thereby, it has sufficient mechanical strength with respect to the rotational bending load applied to the wheel mounting flange 8, and the durability of the hub wheel 1 is further improved.

  The inner ring member 7 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and has a tapered other side (inner side) facing the double-row outer rolling surfaces 4a and 4a on the outer periphery. Of the inner rolling surface 7a, a small flange 9 on the outer side across the inner rolling surface 7a, and a cylindrical portion 10 extending in the axial direction from the small flange 9 are formed, and the inner side will be described later. A cylindrical connecting portion 11 connected to the outer joint member 20 is formed. A large collar 7b for guiding the tapered roller 6 is formed on the large diameter side of the inner rolling surface 7a.

  The cylindrical portion 10 is formed with an inrow portion 10a that is press-fitted into the small-diameter step portion 1b of the hub wheel 1 via a predetermined shimiro, and a fitting portion 10b is formed at the end of the inrow portion 10a. A serration (or spline) 11 a is formed on the inner periphery of the connecting portion 11. And the cylindrical part 10 and the connection part 11 of the both sides including the inner side rolling surface 7a are hardened by the induction hardening in the range of 58-64HRC. In addition, the fitting part 10b of the cylindrical part 10 is left raw after forging.

  Double row tapered rollers 6 and 6 are accommodated between the double row outer rolling surfaces 4a and 4a of the outer member 4 and the inner rolling surfaces 1a and 7a of the inner member 5 opposed thereto, and the cage. 12 and 13 are held so as to roll freely. This wheel bearing device is a so-called back-to-back type double-row tapered roller bearing in which the action lines in the action direction of the forces applied to the rolling surfaces 4a, 1a and 4a, 7a are separated in the axial direction toward the axial center. It is composed. Further, seals 14 and 14 are attached to the opening portion of the annular space formed by the outer member 4 and the inner member 5, and leakage of lubricating grease sealed inside the bearing and rainwater or the like inside the bearing from the outside. Prevents dust from entering.

  Here, the concavo-convex portion 15 is formed on the inner periphery of the hub wheel 1, and a hardened layer is formed with a surface hardness 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. The concave and convex portion 15 is formed in the shape of an iris knurl, and is a cross groove formed by orthogonally crossing a plurality of annular grooves formed independently by turning or the like and a plurality of axial grooves formed by broaching or the like. Alternatively, it consists of a cross groove composed of spiral grooves inclined with respect to each other. Further, in order to ensure good biting property, the tip of the concavo-convex portion 15 is formed in a spire shape such as a triangular shape.

  The hub wheel 1 and the inner ring member 7 are joined by first joining the end surface of the small-diameter step portion 1b of the hub wheel 1 to the end surface of the small flange 9 of the inner ring member 7 until the cylindrical portion of the inner ring member 7 is abutted. The hub wheel 1 is externally fitted to 10. Then, a diameter expanding jig such as a punch is pushed into the inner diameter of the fitting portion 10b in the cylindrical portion 10 to expand the diameter of the fitting portion 10b, and the fitting portion 10b is bitten into the uneven portion 15 of the hub wheel 1. Caulking, the hub wheel 1 and the inner ring member 7 are integrally plastically coupled. 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.

  In the present embodiment, the cages 12 and 13 are formed by injection molding by adding a reinforcing material such as GF (glass fiber) to a base of a thermoplastic resin such as PA (polyamide) 66. The outer cage 12 is configured to be able to hold the tapered roller 6 in the pocket in a fall-off prevention state. That is, the width of the opening on the outer diameter side of the pocket in the cage 12 is such that the tapered roller 6 is in contact with the tapered side surface and guided without coming out to the outer diameter side, and the inner diameter side opening. The width of the tapered roller 6 is slightly narrower than the outer diameter of the corresponding portion of the tapered roller 6, and the tapered roller 6 can be pushed into the pocket from the inner diameter side by elastic deformation of the cage 12. The tapered roller 6 has a width that does not fall off naturally toward the inner diameter side.

  The seal 14 is disposed opposite to the seal plate 18 having an annular seal plate 18 composed of a core bar 16 and a seal member 17 integrally vulcanized and bonded to the core bar 16, and has a substantially L-shaped cross section. And a so-called pack seal. The core metal 16 and the slinger 19 are formed by press working from an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC type or the like). Yes.

  The constant velocity universal joint 3 includes an outer joint member 20, a joint inner ring 21, a cage 22, and a torque transmission ball 23. The outer joint member 20 includes a cup-shaped mouth portion 24, a shoulder portion 25 that forms the bottom portion of the mouth portion 24, and a cylindrical connecting portion 26 that extends from the shoulder portion 25 in the axial direction. A curved track groove 24 a extending in the axial direction is formed on the inner periphery of the mouse portion 24, and a track groove 21 a corresponding to the track groove 24 a is formed on the outer periphery of the joint inner ring 21. In addition, a serration (or spline) 26 a that engages with the serration 11 a formed on the connecting portion 11 of the inner ring member 7 described above is formed on the outer periphery of the connecting portion 26.

  In the present embodiment, the connecting portion 11 of the inner ring member 7 is abutted against the shoulder portion 25 of the outer joint member 20, and both the connecting portions 11 and 26 are fitted so as to be able to transmit torque via the serrations 11a and 26a. A female thread 26b is formed in the connecting portion 26 of the joint member 20. By fastening a fixing bolt 27 to the female thread 26b, the inner ring member 7 and the outer joint member 20 are detachably tightened in the axial direction. By adopting such a configuration, it is possible to provide a wheel bearing device in which the load capacity or rigidity of the double-row bearing row is increased while reducing the weight and size.

Next, a method for assembling the wheel bearing device according to the present embodiment will be described in detail with reference to FIGS. 2 (a) to 2 (c) and FIG. 3.
First, as shown in FIG. 2A, the tapered roller 6 is held by the cage 12 to constitute a roller assembly, and this roller assembly is arranged on the outer side of the outer member 4 placed vertically. The seal plate 18 of the seal 14 is press-fitted into the outer end of the outer member 4 after being inserted into the rolling surface 4a. Then, as shown in (b), the outer member 4 on which the outer roller assembly is temporarily assembled is inverted and fitted into the hub wheel 1 at this point. At this time, since the tapered roller 6 is held by the cage 12, it does not fall off to the inner diameter side. Further, as shown in (c), after the outer member 4 is fitted and inserted into the hub wheel 1 placed vertically on the base B, the inner ring member 7, the tapered roller 6 and the cage 13 are moved. After being assembled and sub-united, it is inserted into the outer side rolling surface 4a on the inner side. Accordingly, the cylindrical portion 10 of the inner ring member 7 is inserted into the inner diameter of the hub wheel 1, and an annular space formed by the inner periphery of the inner side end of the outer member 4 and the outer periphery of the connecting portion 11 of the inner ring member 7. A seal 14 is attached. Here, as with the hub wheel 1, the small ring 9 of the inner ring member 7 is abolished and a retainer (not shown) that can hold the tapered roller 6 in a fall-off prevention state is used, so that the inner side of the outer member 4 Alternatively, the roller assembly may be inserted into the outer rolling surface 4 a in advance, and finally the inner ring member 7 may be inserted into the outer member 4.

  Next, as shown in FIG. 3, the punch P is pushed into the inner diameter of the hub wheel 1 in the direction of the arrow to expand the diameter of the fitting portion 10 b of the inner ring member 7. In a so-called diameter-enlarged caulking process in which the portion 15 is bitten and caulked, the hub wheel 1 is placed on the base B in a non-rotatable manner, and the outer member 4 is rotated with respect to the hub wheel 1 while being expanded. Radial caulking is performed. As a result, the double-row tapered rollers 6 and 6 smoothly move on the respective rolling surfaces and are stably aligned with the large flanges 1c and 7b, so that a predetermined preload can be applied with high accuracy. By adopting such an assembling method, assembly by an automatic machine becomes possible, and the number of assembling steps can be reduced. The outer member 4 may be swung (reciprocated) relative to the hub wheel 1.

  Furthermore, in this embodiment, the preload monitoring device 30 is disposed in the wheel bearing device. The preload monitoring device 30 measures the rotational torque of the outer member 4 that is rotated when the diameter of the wheel bearing device is increased, detects whether there is an abnormality during assembly, and uses this rotational torque as a medium to determine the amount of preload. Converted and set to a predetermined bearing preload amount.

  The preload monitoring device 30 includes a motor M that rotationally drives the outer member 4 via a speed reducer (not shown), a torque detector 31 that includes a wattmeter that detects rotational torque of the motor M, and detected rotational torque. And a determiner 32 that compares the value with a predetermined value set in advance. In the preload monitoring device 30, the motor M is driven, the outer member 4 is rotated via a reduction gear, and the rotational torque of the outer member 4 is detected by the torque detector 31. Then, a preload amount is obtained based on the detected rotational torque, and the diameter expansion caulking is terminated when the preload amount reaches a predetermined value set in advance, that is, a preload amount suitable for the wheel bearing device. Since such a preload monitoring device 30 is arranged in the diameter expansion caulking device, it is possible to measure and manage the preload amount of the bearing accurately and stably.

  Fig.4 (a) is a longitudinal cross-sectional view which shows 2nd Embodiment of the bearing apparatus for wheels which concerns on this invention, (b) is a principal part enlarged view of (a). Note that this embodiment basically differs from the above-described embodiment (FIG. 1) only in the configuration of the outer bearing, and other parts having the same parts or the same functions are denoted by the same reference numerals. Detailed description is omitted.

  In this wheel bearing device, the hub wheel 33 and the double-row rolling bearing 34 are formed as a subunit, and are unitized so as to be separable from the constant velocity universal joint 35. The double row rolling bearing 34 includes an outer member 36, an inner member 37, and a plurality of balls 40 and tapered rollers 6 accommodated between the two members, and balance of load capacity or rigidity of the double row bearing row. The device is made compact in the axial direction.

  The outer member 36 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and integrally has a vehicle body mounting flange 4b for mounting to the vehicle body (not shown) on the outer periphery. The inner side rolling surface 36a on the outer side of the arc shape and the outer side rolling surface 4a on the inner side of the tapered shape are formed, and the surface hardness is hardened in the range of 58 to 64 HRC by induction hardening.

  On the other hand, the inner member 37 includes a hub ring 33 and a cylindrical inner ring member 38 fitted in the hub ring 33. The hub wheel 33 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon, such as S53C, and has a wheel mounting flange 8 for mounting a wheel on an end portion on the outer side. A side inner rolling surface 33a and a cylindrical small diameter step portion 33b extending in the axial direction from the inner rolling surface 33a are formed. A hardened layer is formed with a surface hardness of 58 to 64 HRC by induction hardening from the base portion 8b of the wheel mounting flange 8 to which the outer seal 42 is in sliding contact to the inner rolling surface 33a and the small diameter step portion 33b. ing.

  On the other hand, the inner ring member 38 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and has a tapered inner side facing the outer raceway surface 4a of the outer member 36 on the outer periphery. An inner rolling surface 7a, a small flange 9 on the outer side across the inner rolling surface 7a, and a cylindrical portion 10 extending in the axial direction from the small flange 9 are formed, and an outer side, which will be described later, is formed on the inner side. A cylindrical connecting portion 39 connected to the joint member is formed. A serration (or spline) 39 a is formed on the outer periphery of the connecting portion 39.

  A plurality of balls 40 and tapered rollers 6 are accommodated and held between the double row outer rolling surfaces 36a, 4a of the outer member 36 and the inner rolling surfaces 33a, 7a of the inner member 37 opposed thereto. It is hold | maintained so that rolling is possible by the container 41,13. Seals 42 and 14 are attached to the opening of the annular space formed by the outer member 36 and the inner member 37, and leakage of lubricating grease sealed inside the bearing and rainwater and Prevents dust from entering. End caps 43 and 44 are attached to the end of the hub wheel 33 and the inner periphery of the outer joint member 45 to prevent rainwater or the like from entering the plastic coupling portion and rusting the portion. The grease sealed in 24 is prevented from leaking outside.

  The constant velocity universal joint 35 includes an outer joint member 45, a joint inner ring 21, a cage 22, and a torque transmission ball 23. The outer joint member 45 includes a cup-shaped mouth portion 24 and a connecting portion 46 that extends in a cylindrical shape from the bottom of the mouth portion 24. A serration (or spline) 46 a that engages with the serration 39 a formed on the connecting portion 39 of the inner ring member 38 described above is formed on the inner periphery of the connecting portion 46.

  In this embodiment, as shown in an enlarged view in FIG. 4B, the end surface of the inner ring member 38 is abutted against the connecting portion 46 of the outer joint member 45 via an elastic member 47 made of an O-ring or the like. 39 and 46 are fitted via serrations 39a and 46a so that torque can be transmitted. In addition, annular grooves 39b and 46b are formed at the end portions of the serrations 39a and 46a, and clips 48 including end rings are attached to the annular grooves 39b and 46b, so that the inner ring member 38 and the outer joint member 45 are connected to the shaft. It is integrally connected so as to be separable in the direction. Thereby, it is possible to fix the double row rolling bearing 34 and the constant velocity universal joint 35 with a simple configuration so as to be separable with one touch.

  Also in the present embodiment, a diameter expansion jig such as a punch is pushed into the inner diameter of the hub wheel 33 to expand the diameter of the fitting portion 10b of the inner ring member 38, and the fitting portion 10b is formed on the uneven portion 15 of the hub wheel 33. In this diameter expansion caulking process, diameter expansion caulking is performed while rotating the outer member 36 with respect to the hub wheel 33. Thereby, the tapered roller 6 on the inner side smoothly moves on the inner rolling surface 7a and is stably aligned with the large collar 7b, and a predetermined preload can be applied with high accuracy.

  FIG. 5 is a longitudinal sectional view showing a third embodiment of the wheel bearing device according to the present invention. In addition, the same code | symbol is attached | subjected to the site | part which has the same components same site | part as the embodiment mentioned above, or the same function, and detailed description is abbreviate | omitted.

  This wheel bearing device is referred to as the fourth generation, and the hub wheel 1, the double row rolling bearing 80 and the constant velocity universal joint 81 are configured as a unit. The double-row rolling bearing 80 includes an inner member 82, an outer member 4, and double-row tapered rollers 6, 6 accommodated between both members 82, 4 so as to roll freely. The inner member 82 includes a hub wheel 1 and an outer joint member 83 that is fitted into the hub wheel 1 and is plastically coupled.

  The constant velocity universal joint 81 includes an outer joint member 83, a joint inner ring 21, a cage 22, and a torque transmission ball 23. The outer joint member 83 is made of medium carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and has a cup-shaped mouth portion 24, a shoulder portion 84 that forms the bottom of the mouth portion 24, and the shoulder portion 84. And a cylindrical portion 10 extending in the axial direction are integrally formed. On the outer periphery of the shoulder 84, the inner rolling surface 7 a on the tapered inner side facing the double row outer rolling surfaces 4 a, 4 a of the outer member 4, and the larger diameter side of the inner rolling surface 7 a A large collar 7b for guiding the tapered roller 6 and a cylindrical portion 83a extending straight from the small diameter side are integrally formed. And the surface hardness is hardened in the range of 58-64 HRC by induction hardening over the track groove 24a and the shoulder part 84 in which the seal 14 fits to the inner rolling surface 7a and the cylindrical part 10.

  Double row tapered rollers 6 and 6 are accommodated between the double row outer raceway surfaces 4a and 4a of the outer member 4 and the double row inner raceway surfaces 1a and 7a opposed to these, and the cage. 12 and 12 are held so that they can roll and cannot be dropped off, and constitute a back-to-back type double row tapered roller bearing.

  Also in the present embodiment, a diameter expanding jig such as a punch is pushed into the inner diameter of the hub wheel 1 to expand the diameter of the fitting portion 10b of the outer joint member 83, and the fitting portion 10b is used as the uneven portion 15 of the hub wheel 1. In the diameter-enlarged caulking process, the diameter-enlarged caulking is performed while the outer member 4 is rotationally moved with respect to the hub wheel 1. Thereby, the double-row tapered rollers 6 and 6 smoothly move on the inner rolling surfaces 1a and 7a and are stably aligned with the large flanges 1c and 7b, and a predetermined preload can be applied with high accuracy.

  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.

  The wheel bearing device according to the present invention is applied to a wheel bearing device of a third or fourth generation structure having a hub wheel having a wheel mounting flange at one end and an inner rolling surface formed directly on the outer periphery. be able to.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. (A)-(c) is explanatory drawing which shows the assembly method of the wheel bearing apparatus of FIG. It is explanatory drawing which shows the diameter expansion caulking process of the wheel bearing apparatus of FIG. (A) is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. (B) is the principal part enlarged view of (a). It is a longitudinal cross-sectional view which shows 3rd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus.

Explanation of symbols

1, 33 ···················· Hub wheel 1a, 7a, 33a ······· Inner rolling surface 1b ·········・ Small-diameter stepped portion 1c, 7b ..... Large cage 2,34,80 ..... Double-row rolling bearings 3, 35, 81 .....・ ・ ・ ・ ・ ・ Constant velocity universal joints 4, 36 ・ ・ ・ ・ ・ ・ ・ ・ Outer member 4a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer rolling surface 4b Car body mounting flange 5, 37, 82 ... Inner member 6 ... ... Conical rollers 7, 38 ......... Inner ring member 8 ......... Wheel mounting flange 8a ... ..... hub bolt 8b ..... base 9 ······························································································· ...... ········································································ Connection parts 11a, 26a, 39a, 46a ... Serrations 12, 13, 41 ...・ ・ Retainer 14, 42 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal 15 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Concavity and convexity 16 ・ ・ ・ ・ ・ ・・ ・ ・ ・ Core 17 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Sealing member 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Seal plate 19 ・ ・ ・ ・ ・ ・... Slinger 20, 45, 83 ... Outer joint member 21 ... Joint inner ring 21a, 24a ... .... Track groove 22 ... ... Cage 23 ... Torque transmission ball 24 ... Mouse part 25, 84 ... shoulder part 26b ... female screw 27 ... fixing bolt 30 ... preload monitoring device 31 ... torque detector 32 ... ... Determining devices 39b, 46b ......... annular groove 40 ......... balls 43, 44 ... .... End cap 47 ... Elastic member 48 ... 51 Clip 51 ...・ ・ ・ ・ ・ Hub wheels 51a, 57a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inside Rolling surface 51b ... Small diameter step 52 ... Double row rolling bearing 53 ... ... Constant velocity universal joint 54 ... Outer member 54a ... Outer rolling surface 54b ... Body mounting flange 55 ... Inner member 56 ... ... Ball 57 ... Inner ring member 58 ... Wheel mounting flange 59 ... ···························································. ······························. ·········· Male spline 61b ························································· ... outer joint member 65 ... joint inner ring 66 ... Torque transmission ball 67 ... Cage 68 ... Mouse 69 ... ..... shoulder 69a ..... female spline 70 ..... half shaft 71 ... ········· Boot 71a, 71b ······································· Clip B・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Base M ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Motor

Claims (5)

An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, and having a double row outer rolling surface formed on the inner periphery;
A wheel mounting flange for mounting a wheel at one end is integrally formed, one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a small diameter step extending in the axial direction from the inner rolling surface A hub wheel formed with a portion, and the other inner rolling surface that is fitted to the hub wheel and that faces the outer rolling surface of the double row is formed on the outer periphery, and from the inner rolling surface to the axial direction An inner member formed of an inner ring member or a constant velocity universal joint member formed with a cylindrical portion extending to
A double row rolling element housed between the rolling surfaces of the inner member and the outer member so as to be freely rollable via a cage;
A seal attached to an opening of an annular space formed by the outer member and the inner member;
The hub wheel and the inner ring member or the outer joint are formed by forming a hardened concave and convex portion on the inner diameter of the hub ring and expanding the fitting portion formed at the end of the cylindrical portion to bite into the concave and convex portion. In the wheel bearing device in which the member is integrally plastically coupled,
Among the double row rolling elements, at least the inner side rolling element is constituted by a tapered roller, and a large collar for guiding the tapered roller is formed on the large diameter side of the inner rolling surface. Wheel bearing device.   The inner member includes the hub ring and an inner ring member fitted into the hub ring, and a cylindrical connecting portion projects from the inner side of the inner ring member. The wheel bearing device according to claim 1, wherein the outer joint member and the serration are coupled so as to be capable of transmitting torque and being separable.   3. The wheel bearing according to claim 1, wherein the cage is formed from a synthetic resin by injection molding, and at least the outer side cage is configured to be able to hold the rolling element in a fall-off prevention state in the pocket. apparatus. An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, and having a double row outer raceway formed on the inner periphery;
A wheel mounting flange for mounting a wheel at one end is integrally formed, an outer side inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a small diameter extending in the axial direction from the inner rolling surface A hub wheel formed with a stepped portion, and an inner side inner rolling surface that is fitted to the hub wheel and faces the outer rolling surface of the double row are formed on the outer periphery, and from the inner rolling surface. An inner member formed of an inner ring member formed with a cylindrical portion extending in the axial direction or an outer joint member of a constant velocity universal joint;
A double row rolling element housed between the rolling surfaces of the inner member and the outer member so as to be freely rollable via a cage;
A seal attached to an opening of an annular space formed by the outer member and the inner member;
The hub wheel and the inner ring member or the outer joint are formed by forming a hardened concave and convex portion on the inner diameter of the hub ring and expanding the fitting portion formed at the end of the cylindrical portion to bite into the concave and convex portion. In the method of assembling the wheel bearing device in which the members are integrally plastically coupled,
The rolling element is held by the outer cage, and is inserted into an outer rolling surface on the outer side of the outer member placed vertically, and then the outer member is placed on the outer end of the outer member. The outer seal is press-fitted and the outer member is inverted and inserted into the hub wheel placed vertically, and the tapered roller is held on the inner rolling surface by the inner-side cage. In this state, the cylindrical portion is fitted into the hub wheel while being inserted into the outer rolling surface on the inner side, and finally the inner space is formed in an annular space formed by the outer member and the inner member. A wheel bearing device characterized in that a side seal is mounted and the inner member is plastically coupled by diameter expansion caulking while rotating or swinging the outer member with respect to the hub wheel. Assembly method.   A preload monitor device comprising a motor that rotationally drives the outer member, a torque detector that detects the rotational torque of the motor, and a determiner that compares the detected rotational torque with a predetermined value set in advance. And measuring the rotational torque of the outer member to detect whether there is an abnormality during assembly, and converting the preload amount using this rotational torque as a medium to set the predetermined bearing preload amount. 5. A method of assembling the wheel bearing device according to 4.

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