JP5236348B2 - Wheel bearing device - Google Patents

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel with respect to a vehicle body in a vehicle such as an automobile.

  The wheel bearing device has evolved from a structure in which a double row rolling bearing called a first generation is used alone to a second generation in which a vehicle body mounting flange is integrated with an outer member. The third generation in which one inner raceway surface of the double row rolling bearing is integrally formed on the outer periphery of the hub ring integrally having a ring, and further, the constant velocity universal joint is integrated with the hub ring. 4th generation has been developed in which the other inner raceway surface of the double-row rolling bearing is integrally formed on the outer periphery of the outer joint member that constitutes.

  For example, Patent Document 1 describes what is called a third generation. As shown in FIG. 16, the wheel bearing device called the third generation includes a hub wheel 152 having a flange 151 extending in the outer diameter direction, and a constant velocity universal joint 154 to which an outer joint member 153 is fixed. And an outer member 155 disposed on the outer peripheral side of the hub wheel 152.

  The constant velocity universal joint 154 includes an outer joint member 153, an inner joint member 158 disposed in the bowl-shaped portion 157 of the outer joint member 153, and the inner joint member 158 and the outer joint member 153. A ball 159 to be disposed and a holder 160 for holding the ball 159 are provided. Further, a spline portion 161 is formed on the inner peripheral surface of the center hole of the inner joint member 158, and an end spline portion of a shaft (not shown) is inserted into the center hole, and the spline portion 161 on the inner joint member 158 side The spline portion on the shaft side is engaged.

  The hub wheel 152 includes a cylindrical shaft portion 163 and the flange 151, and a short wheel and a brake rotor (not shown) are attached to the outer end surface 164 (end surface on the anti-joint side) of the flange 151. A cylindrical pilot portion 165 is provided so as to protrude. The pilot portion 165 includes a large-diameter first portion 165a and a small-diameter second portion 165b. A brake rotor is externally fitted to the first portion 165a, and a wheel is externally fitted to the second portion 165b.

  A notch 166 is provided on the outer peripheral surface of the end portion of the shaft portion 163 on the hook-shaped portion 157 side, and the inner ring 167 is fitted into the notch 166. A first inner raceway surface 168 is provided near the flange on the outer peripheral surface of the shaft portion 163 of the hub wheel 152, and a second inner raceway surface 169 is provided on the outer peripheral surface of the inner ring 167. A bolt mounting hole 162 is provided in the flange 151 of the hub wheel 152, and a hub bolt for fixing the wheel and the brake rotor to the flange 151 is mounted in the bolt mounting hole 162.

  The outer member 155 is provided with two rows of outer raceways 170 and 171 on its inner periphery, and a flange (vehicle body mounting flange) 151 on its outer periphery. Then, the first outer raceway surface 170 of the outer member 155 and the first inner raceway surface 168 of the hub ring 152 face each other, and the second outer raceway surface 171 of the outer member 155 and the raceway surface 169 of the inner ring 167 are opposed to each other. Opposed and a rolling element 172 is interposed between them.

  The shaft portion 173 of the outer joint member 153 is inserted into the shaft portion 163 of the hub wheel 152. The shaft portion 173 has a threaded portion 174 formed at the end of the ridged portion, and a spline portion 175 is formed between the threaded portion 174 and the hooked portion 157. A spline portion 176 is formed on the inner peripheral surface (inner diameter surface) of the shaft portion 163 of the hub wheel 152, and when the shaft portion 173 is inserted into the shaft portion 163 of the hub wheel 152, The spline portion 175 engages with the spline portion 176 on the hub wheel 152 side.

Then, the nut member 177 is screwed to the screw portion 174 of the shaft portion 173 protruding from the shaft portion 163, and the hub wheel 152 and the outer joint member 153 are connected. At this time, the inner end surface (back surface) 178 of the nut member 177 contacts the outer end surface 179 of the shaft portion 163, and the end surface 180 on the shaft portion side of the hook-shaped portion 157 contacts the outer end surface 181 of the inner ring 167. That is, by tightening the nut member 177, the hub wheel 152 is sandwiched between the nut member 177 and the hook-shaped portion 157 via the inner ring 167.
JP 2004340403 A

  Conventionally, as described above, the spline portion 175 on the shaft portion 173 side and the spline portion 176 on the hub wheel 152 side are engaged. For this reason, it is necessary to perform spline processing on both the shaft portion 173 side and the hub wheel 152 side, which increases the cost, and at the time of press-fitting, the spline portion 175 on the shaft portion 173 side and the spline portion 176 on the hub wheel 152 side. It is necessary to match the unevenness of the teeth. At this time, if the teeth are pressed by matching the tooth surfaces, the uneven teeth may be damaged (peeled). Moreover, if it press-fits by matching the large diameter of an uneven | corrugated tooth | gear, without matching a tooth surface, the play of a circumferential direction will arise easily. As described above, when there is a backlash in the circumferential direction, the transmission performance of the rotational torque is inferior and abnormal noise may occur. For this reason, it has been difficult to establish both the damage to the concavo-convex teeth and the play in the circumferential direction when using spline fitting as in the prior art.

  By the way, in spline fitting, even if the adhesiveness between the male spline and the female spline is improved so that the play in the circumferential direction does not occur, if the driving torque is applied, the male spline and the female spline are separated. Relative displacement may occur. If such relative displacement occurs, fretting wear occurs, and the abrasion powder may cause ablation wear. As a result, there is a possibility that rattling occurs at the spline fitting site or that stable torque transmission cannot be performed.

  In view of the above problems, the present invention can suppress circumferential backlash, and is excellent in connection workability between the hub wheel and the outer joint member of the constant velocity universal joint, and at the same time with the hub wheel and the constant velocity. Provided is a wheel bearing device that can be separated from an outer joint member of a universal joint, has excellent maintainability, and can transmit torque stably over a long period of time.

The wheel bearing device of the present invention includes a hub wheel having a flange for mounting on a wheel, a double row rolling bearing, and a constant velocity universal joint having an outer joint member as a unit, a hub wheel, and a hub. a wheel bearing device and the shaft portion is detachably coupled via a recess-projection fitting structure of the outer joint member being fitted into the hole of the wheel, the outer diameter surface and the hub of the shaft section of the outer joint member A convex portion that is provided on one of the inner diameter surfaces of the hole portion of the ring and that extends in the axial direction is press-fitted into the other along the axial direction, and a concave portion that is closely fitted to the convex portion is provided on the other side. formed by cutting into, constitute the recess-projection fitting structure fitting contact regions throughout the convex portion and the concave portion are in close contact, in the state where the recess-projection fitting structure is configured, the hub wheel and the outer joint The shaft portion of the member is a screw hole provided at the end portion of the shaft portion of the outer joint member and the screw hole. Fixed by bolts coupling means on the axis and a threaded bolt member, the recess-projection fitting structure is allowed separated by axial pulling force applied after removal of the bolt member, uneven reinject into the recess of the convex portions after the separation of the fitting structure is carried out by tightening the bolt member, the bolt member strength is weakest is provided, this intensity weakest part, upon the re-press-fitting It is characterized in that the weakest strength portion is set to a strength that causes prior breakage due to an excessive axial force generated with the tightening of the bolt member .

  According to the wheel bearing device of the present invention, the concave / convex fitting structure has the entire fitting contact portion between the convex portion and the concave portion in close contact with each other. No gap is formed.

  In addition, if an axial pulling force is applied to the shaft portion of the outer joint member, the outer joint member can be removed from the hole of the hub wheel. In addition, after the shaft portion of the outer joint member is pulled out from the hole portion of the hub wheel, if the shaft portion of the outer hand member is press-fitted again into the hole portion of the hub wheel, the entire fitting contact region between the convex portion and the concave portion can be obtained. The concave-convex fitting structure can be configured to closely contact each other. Further, the re-pressing can be performed by bolt tightening by a bolt coupling means, and the axial removal of the shaft portion of the outer joint member from the hub wheel is restricted.

  By the way, at the time of re-pressing after separation, there is a case where it is press-fitted in a direction inclined with respect to the misalignment or the device axis. In such a case, an excessive load (excessive axial force) is applied to the bolt member, and misalignment or oblique fitting of the concave-convex fitting structure occurs. For this reason, an uneven | corrugated fitting structure may be damaged, or the whole fitting contact site | part of a convex part and a recessed part cannot be stuck. For this reason, in the present invention, the bolt member is provided with the weakest strength portion that is damaged in advance by excessive axial force generation. For this reason, when excessive axial force is added to a bolt member, it will be damaged in this strength weakest part. In other words, in a misaligned state where excessive axial force is applied, the bolt member is damaged, and the concave-convex fitting structure is damaged, or the adhesiveness of the fitting contact portion between the convex portion and the concave portion is reduced. Can be prevented.

  The shaft press-fitting guide part of the outer joint member is preferably provided on the convex part press-fitting start side. By providing the shaft portion press-fitting guide portion, the shaft portion of the outer joint member can be press-fitted along the shaft portion press-fitting guide portion when press-fitting the shaft portion of the outer joint member into the hole portion of the hub wheel.

  The outer joint member includes a mouth portion in which the inner joint member is housed, and a shaft portion protruding from the bottom portion of the mouth portion. It is preferable that the inner ring of the rolling bearing fitted on the ring is fixed and the caulking portion is brought into contact with the opposing surface of the outer joint member facing the ring.

  Since the caulking portion is brought into contact with the opposing surface of the outer joint member of the constant velocity universal joint facing the caulking portion, the axial bending rigidity of the shaft portion of the outer joint member is improved. This bending occurs due to a secondary moment generated at a high operating angle of the constant velocity universal joint or an axial load input from the tire side during turning.

  At least one of the caulking portion of the hub wheel and the opposing surface of the outer joint member facing the hub ring, or the seat surface of the bolt member of the bolt coupling means and the receiving surface receiving the seat surface. It is preferable to interpose a sealing material on either side.

  A convex portion extending in the axial direction provided on one of the outer diameter surface of the shaft portion of the outer joint member and the inner diameter surface of the hole portion of the hub wheel is press-fitted into the other along the axial direction, and is projected to the other. A concave portion that closely fits to the convex portion is formed at the portion to constitute the concave-convex fitting structure. In other words, the shape of the convex portion is transferred to the concave portion forming surface on the other side. At this time, the convex portion bites into the concave-part forming surface on the other side, so that the hole portion is slightly expanded in diameter, allowing the convex portion to move in the axial direction and stopping the axial movement. In this case, the diameter of the hole is reduced to return to the original diameter. Thereby, the whole recessed part fitting part of a convex part closely_contact | adheres to the corresponding recessed part.

  A convex portion of the concave-convex fitting structure is provided on the shaft portion of the outer joint member of the constant velocity universal joint, and at least the hardness of the axial end portion of the convex portion is higher than the inner diameter portion of the hole portion of the hub wheel, By pressing the shaft portion into the hole portion of the hub wheel from the axial end portion side of the convex portion, a concave portion that closely fits the convex portion is formed on the inner diameter surface of the hole portion of the hub wheel at the convex portion. You may comprise an uneven | corrugated fitting structure. Further, a convex portion of the concave-convex fitting structure is provided on the inner diameter surface of the hole portion of the hub wheel, and at least the hardness of the axial end portion of the convex portion is set to the outer diameter portion of the shaft portion of the outer joint member of the constant velocity universal joint. The convex portion on the hub wheel side is press-fitted into the shaft portion of the outer joint member from the axial end portion side, thereby projecting to the outer diameter surface of the shaft portion of the outer joint member. The concave-convex fitting structure may be formed by forming a concave portion that closely fits to the portion.

  It is preferable that the intermediate portion in the protruding direction of the convex portion corresponds to the position of the concave portion forming surface before the hole concave portion of the hub wheel is formed. At this time, the inner diameter dimension of the inner diameter surface of the hole of the hub wheel is set to be smaller than the maximum diameter dimension of the circle connecting the apexes of the protrusions and larger than the maximum diameter dimension of the recesses on the outer diameter surface of the shaft between the protrusions. There is a case. In addition, the diameter dimension of the arc connecting the vertices of the plurality of convex portions of the hole portion of the hub wheel is made smaller than the outer diameter size of the shaft portion of the outer joint member, and the inner diameter size of the inner diameter surface of the hole portion between the convex portions is outside. In some cases, it may be larger than the outer diameter of the shaft portion of the joint member.

  By disposing the intermediate portion in the protruding direction of the convex portion on the concave portion forming surface before forming the concave portion, the convex portion bites into the concave portion forming surface at the time of press-fitting, and the concave portion can be reliably formed.

  It is preferable that the circumferential thickness of the protruding portion intermediate portion of the convex portion is smaller than the circumferential dimension at a position corresponding to the intermediate portion between the convex portions adjacent in the circumferential direction. By setting in this way, the sum of the circumferential thicknesses of the projecting direction intermediate portions of the convex portion is a position corresponding to the intermediate portion in the mating convex portion that fits between the convex portions adjacent in the circumferential direction. Smaller than the sum of the circumferential thicknesses.

  It is preferable to arrange the concave-convex fitting structure at a position directly below the raceway surface of the rolling bearing. That is, if the shaft portion is press-fitted into the hole of the hub wheel, the hub wheel expands. This expansion generates a hoop stress on the raceway surface of the rolling bearing. Here, the hoop stress refers to a force for expanding the diameter in the outer diameter direction. For this reason, when a hoop stress is generated on the bearing raceway surface, there is a risk of causing a reduction in rolling fatigue life and occurrence of cracks. Therefore, by arranging the concave-convex fitting structure at a position directly below the raceway surface of the rolling bearing, generation of hoop stress on the bearing raceway surface can be suppressed.

  The wheel bearing device according to the present invention has a concave-convex fitting structure that integrates the hub ring and the shaft portion of the outer joint member of the constant velocity universal joint that is inserted into the hole of the hub ring. The play in the circumferential direction of the structure portion can be eliminated. For this reason, all of the uneven fitting parts contribute to rotational torque transmission, stable torque transmission is possible, and no abnormal noise is generated.

  In addition, by applying an axial pulling force to the shaft portion of the outer joint member, the outer joint member can be removed from the hole of the hub wheel, so that the workability (maintenability) of repair and inspection of each part is improved. Improvements can be made. In addition, after each part is repaired and inspected, it can be re-pressed by bolt tightening by means of the bolt coupling means, and the workability can be improved. In particular, in a state where an excessive axial force is applied due to misalignment, oblique press-fitting, etc., the bolt member will be damaged, and the concave-convex fitting structure will be damaged, or the fitting contact part between the convex part and the concave part will be damaged. It is possible to prevent the adhesion from being lowered. For this reason, also in the re-pressing process, the uneven | corrugated fitting structure which the fitting contact site | part whole area of a convex part and a recessed part closely_contact | adhere can be comprised, and the wheel bearing apparatus in which stable torque transmission is possible is comprised again. Can do.

Since the hub wheel and the constant velocity universal joint are fixed through the bolt coupling means, the axial disconnection of the shaft portion of the outer joint member from the hub wheel is restricted, and a stable connected state can be maintained.

  By providing the shaft portion press-fitting guide portion of the outer joint member, the shaft portion can be press-fitted along the shaft portion press-fitting guide portion when press-fitting the shaft portion into the hole of the hub wheel. As a result, stable press-fitting is possible, and it is possible to prevent misalignment and tilting.

  By bringing the caulking portion into contact with the opposing surface of the outer joint member, the axial bending rigidity of the shaft portion of the outer joint member is improved, and it is strong against bending and is a high-quality product with excellent durability. It becomes. In addition, positioning at the time of press-fitting can be configured by this contact. As a result, the dimensional accuracy of the wheel bearing device can be stabilized, and the axial length of the concave-convex fitting structure disposed along the axial direction can be secured to a stable length. Improvements can be made. Furthermore, a seal structure can be formed by this contact, foreign matter can be prevented from entering the concave-convex fitting structure from the caulking portion side, and the concave-convex fitting structure can maintain a stable fitting state over a long period of time.

  Since the end of the hub wheel is crimped and preload is applied to the rolling bearing, it is not necessary to apply preload by the mouth portion of the outer joint member. For this reason, it is possible to press-fit the shaft portion of the outer joint member without considering the preload, and it is possible to improve the connectivity (assembly property) between the hub wheel and the outer joint member.

  If a sealing material is interposed between the caulking portion and the opposing surface of the outer joint member facing the caulking portion, it is possible to prevent rainwater, foreign matter, and the like from entering the concave-convex fitting structure. Further, it is possible to prevent intrusion of rainwater, foreign matter and the like into the concave-convex fitting structure between the bearing surface of the bolt shaft of the bolt coupling means and the receiving surface receiving the bearing surface.

  A convex portion provided on either the outer diameter surface of the shaft portion of the outer joint member or the inner diameter surface of the hole portion of the hub wheel is press-fitted into the other along the axial direction, thereby closely fitting to this convex portion. A concave portion to be formed can be formed. For this reason, an uneven | corrugated fitting structure can be formed reliably. Moreover, it is not necessary to form a spline portion or the like on the member where the recess is formed, and it is excellent in productivity and does not require the phase alignment between the splines. Damage to the tooth surface can be avoided and a stable fitting state can be maintained.

  Moreover, while providing the convex part of the concave-convex fitting structure on the shaft part of the outer joint member of the constant velocity universal joint, the hardness of the axial end of the convex part is higher than the inner diameter part of the hole of the hub wheel, If the shaft portion is press-fitted into the hole of the hub wheel from the axial end portion side of the convex portion, the hardness on the shaft portion side can be increased and the rigidity of the shaft portion can be improved. In addition, a convex portion of the concave-convex fitting structure is provided on the inner diameter surface of the hole portion of the hub wheel, and the hardness of the axial end portion of the convex portion is determined from the outer diameter portion of the shaft portion of the outer joint member of the constant velocity universal joint. In the case where the convex portion on the hub wheel side is press-fitted into the shaft portion of the outer joint member from the end portion in the axial direction, there is no need to perform hardness treatment (heat treatment) on the shaft portion side, so that the constant velocity Excellent productivity of universal joint outer joint members.

  By disposing the intermediate portion in the protruding direction of the convex portion on the concave portion forming surface before forming the concave portion, the convex portion bites into the concave portion forming surface at the time of press-fitting, and the concave portion can be reliably formed.

  The convex part on the side where the concave part is formed by making the circumferential thickness of the intermediate part in the protruding direction of the convex part smaller than the dimension at the position corresponding to the intermediate part between the convex parts adjacent in the circumferential direction ( The thickness in the circumferential direction of the projecting intermediate portion of the convex portion between the concave portions formed can be increased. For this reason, the shear area of the convex part of the other party (the convex part having low hardness between the concave parts due to the formation of the concave parts) can be increased, and the torsional strength can be ensured. Moreover, since the tooth thickness of the convex portion on the higher hardness side is small, the press-fitting load can be reduced and the press-fitting property can be improved.

  By arranging the concave-convex fitting structure at a position directly below the raceway surface of the rolling bearing, generation of hoop stress on the bearing raceway surface is suppressed. As a result, it is possible to prevent a bearing failure such as a decrease in rolling fatigue life, occurrence of cracks, and stress corrosion cracking, and a high-quality bearing can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 1 shows a wheel bearing device according to a first embodiment. This wheel bearing device is a hub wheel 1, a double row rolling bearing 2 and a constant velocity universal joint 3 integrated with each other. 1 and the shaft portion 12 of the outer joint member of the constant velocity universal joint 3 that is inserted into the hole portion 22 of the hub wheel 1 are detachably coupled via the concave-convex fitting structure M.

  The constant velocity universal joint 3 includes a plurality of outer rings 5 serving as outer joint members, an inner ring 6 serving as an inner joint member disposed on the inner side of the outer ring 5, and a plurality of torque transmissions interposed between the outer ring 5 and the inner ring 6. The ball 7 and the cage 8 that is interposed between the outer ring 5 and the inner ring 6 and holds the ball 7 are configured as main members. As shown in FIG. 8 and the like, the inner ring 6 is spline-fitted by press-fitting an end portion 10a of the shaft 10 into the shaft hole inner diameter 6a and is coupled to the shaft 10 so as to be able to transmit torque. Note that a retaining ring 9 for retaining the shaft is fitted to the end portion 10a of the shaft 10.

  The outer ring 5 is composed of a mouse part 11 and a stem part (shaft part) 12. The mouse part 11 has a bowl shape opened at one end, and a plurality of track grooves 14 extending in the axial direction are circumferentially formed on the inner spherical surface 13 thereof. It is formed at equal intervals in the direction. In the inner ring 6, a plurality of track grooves 16 extending in the axial direction are formed on the outer spherical surface 15 at equal intervals in the circumferential direction.

  The track groove 14 of the outer ring 5 and the track groove 16 of the inner ring 6 make a pair, and one ball 7 as a torque transmitting element can roll on each ball track constituted by the pair of track grooves 14 and 16. It is incorporated. The ball 7 is interposed between the track groove 14 of the outer ring 5 and the track groove 16 of the inner ring 6 to transmit torque. The cage 8 is slidably interposed between the outer ring 5 and the inner ring 6, contacts the inner spherical surface 13 of the outer ring 5 at the outer spherical surface, and contacts the outer spherical surface 15 of the inner ring 6 at the inner spherical surface. The constant velocity universal joint in this case is a Zepper type, but is another constant velocity universal joint such as an undercut free type having a straight straight portion at the bottom of each track groove 14, 16. May be.

  Further, the opening of the mouse part 11 is closed by a boot 18. The boot 18 includes a large diameter portion 18a, a small diameter portion 18b, and a bellows portion 18c that connects the large diameter portion 18a and the small diameter portion 18b. The large-diameter portion 18a is externally fitted to the opening of the mouse portion 11, and is fastened by the boot band 19a in this state, and the small-diameter portion 18b is externally fitted to the boot mounting portion 10b of the shaft 10, and in this state, the boot band 19b It is concluded.

  As shown in FIGS. 1 and 6, the hub wheel 1 includes a cylindrical portion 20 and a flange 21 provided at an end portion of the cylindrical portion 20 on the opposite joint side. The hole portion 22 of the cylindrical portion 20 has a shaft portion fitting hole 22a and a tapered hole 22b on the anti-joint side, and an inner wall protruding in the inner diameter direction between the shaft portion fitting hole 22a and the tapered hole 22b. 22c is provided. That is, the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 and the hub wheel 1 are coupled to each other through the concave-convex fitting structure M described later in the shaft portion fitting hole 22a. A concave recess 51 is provided on the end surface of the inner wall 22c on the side opposite to the shaft fitting hole.

  The hole 22 has a large-diameter portion 46 on the opening side opposite the inner wall side from the shaft portion fitting hole 22a, and a small-diameter portion 48 on the inner wall side from the shaft portion fitting hole 22a. A tapered portion (tapered hole) 49a is provided between the large diameter portion 46 and the shaft portion fitting hole 22a. The tapered portion 49a is reduced in diameter along the press-fitting direction when the hub wheel 1 and the shaft portion 12 of the outer ring 5 are coupled.

  The rolling bearing 2 includes an inner ring 24 that fits in a stepped portion 23 provided on the joint side of the tubular portion 20 of the hub wheel 1 and an outer portion that is fitted over the tubular portion 20 to the inner ring 24 of the hub wheel 1. And a member 25. The outer member 25 is provided with two rows of outer raceways (outer races) 26 and 27 on its inner circumference, and a first inner raceway (provided on the outer circumference of the first outer raceway 26 and the shaft portion of the hub wheel 1). The inner race) 28 is opposed to the second outer raceway surface 27 and the second inner raceway surface (inner race) 29 provided on the outer peripheral surface of the inner ring 24 is opposed to the ball as the rolling element 30 therebetween. Is installed. For this reason, in this wheel bearing device, the hub ring 1 and the inner ring 24 constitute an inner member 39 of the rolling bearing 2. Seal members S1 and S2 are attached to both openings of the outer member 25.

  A knuckle 34 extending from a vehicle suspension device (not shown) is attached to the outer ring, which is the outer member 25. That is, the entire outer surface of the outer member 25 is a cylindrical surface, and the cylindrical surface 25a is a press-fitting surface into which the knuckle 34 is press-fitted. Accordingly, the outer member 25 can be pressed into the cylindrical inner surface 34 a of the knuckle 34. In this case, it is preferable that the relative axial and circumferential displacement between the knuckle 34 and the outer member 25 is regulated by the tightening allowance between the knuckle press-fitting surface 25a and the inner diameter surface 34a. For example, when the fitting surface pressure between the outer member 25 and the knuckle 34 × the fitting area is defined as a fitting load, a value obtained by dividing the fitting load by the equivalent radial load of the rolling bearing is a creep generation limit. The design specification of the outer member 25, that is, the fitting fastening allowance between the outer member 25 and the knuckle 34 is set in consideration of the creep generation limit factor in advance.

  For this reason, it is possible to prevent the outer member 25 from slipping off in the axial direction and creeping in the circumferential direction by tightening the knuckle press-fitting surface 25a of the outer member 25 and the knuckle inner diameter surface 34a of the knuckle 34. Here, creep means that the bearing surface slightly moves in the circumferential direction due to insufficient fitting tightening allowance or poor processing accuracy of the mating surface, and the mating surface becomes mirrored, and in some cases, seizure or welding occurs with galling. Say. In addition, it is preferable that circumferential grooves are provided in the knuckle press-fitting surface 25a of the outer member 25 and the inner diameter surface 34a of the knuckle 34, and a retaining ring 59 is provided between these circumferential grooves.

  In this case, the end of the hub wheel 1 on the joint side is swaged, and the inner ring 24 is pressed toward the outboard side by the swaged portion 31 to apply preload to the bearing 2. As a result, the inner ring 24 can be fastened to the hub wheel 1. The flange 21 of the hub wheel 1 is provided with a bolt mounting hole 32, and a hub bolt 33 for fixing the wheel and the brake rotor to the flange 21 is mounted in the bolt mounting hole 32. The side that is on the outside of the vehicle when assembled to the vehicle is referred to as the outboard side, and the side that is on the inside of the vehicle when assembled to the vehicle is referred to as the inboard side.

  The shaft portion 12 of the outer ring 5 is provided with a screw hole 50 that opens at the end surface on the anti-joint side (anti-mouse side) in the shaft center portion. The screw hole 50 is a tapered portion 50a whose opening is expanded toward the opening. A small-diameter portion 12b is provided at the end of the shaft portion 12 on the anti-joint side (anti-mouse side). That is, the shaft portion 12 includes a main body portion 12a having a large diameter and a small diameter portion 12b.

  As shown in FIGS. 2 and 3, the concave-convex fitting structure M includes, for example, a convex portion 35 provided in the shaft portion 12 and extending in the axial direction, and an inner diameter surface of the hole portion 22 of the hub wheel 1 (in this case, the shaft The inner surface 37) of the part fitting hole 22a is formed with a concave part 36, and the entire fitting contact part 38 of the convex part 35 and the concave part 36 of the hub wheel 1 fitted to the convex part 35 is in close contact. Yes. That is, a plurality of convex portions 35 are arranged at a predetermined pitch along the circumferential direction on the outer peripheral surface of the shaft portion 12 on the side opposite to the mouse portion, and the inner diameter surface of the shaft portion fitting hole 22a of the hole portion 22 of the hub wheel 1 A plurality of concave portions 36 into which the convex portions 35 are fitted to 37 are formed along the circumferential direction. That is, the convex part 35 and the concave part 36 fitted to this are tight-fitted over the entire circumference in the circumferential direction.

  In this case, each convex portion 35 has a triangular shape (mountain shape) having a convex rounded apex in cross section, and the fitting contact portion (recessed fitting portion) 38 of each convex portion 35 is shown in FIG. It is the range A shown in b), which is the range from the mid-section of the mountain in the cross section to the peak. Further, a gap 40 is formed on the inner diameter side with respect to the inner diameter surface 37 of the hub wheel 1 between the adjacent convex portions 35 in the circumferential direction.

  In this way, the hub wheel 1 and the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 can be connected via the concave-convex fitting structure M. At this time, as described above, the end of the hub wheel 1 on the joint side is swaged, and the swaged portion 31 applies preload to the rolling bearing 2. There is no need to apply a preload to the inner ring 24.

  In this way, the hub wheel 1 and the shaft portion 12 of the outer ring 5 of the constant velocity universal joint 3 can be connected via the concave-convex fitting structure M. At this time, as described above, the end of the hub wheel 1 on the joint side is swaged, and the swaged portion 31 applies preload to the rolling bearing 2. There is no need to apply a preload to the inner ring 24. However, in the present invention, the end portion of the hub wheel 1 (in this case, the outer end surface 31a of the crimping portion 31) and the end surface of the outer ring 5 facing this, that is, the back surface 11a of the mouse portion 11 are brought into contact with each other. . The contact surface pressure in this case is 100 MPa or less.

  A bolt member 54 is screwed into the screw hole 50 of the shaft portion 12 from the anti-joint side. As shown in FIGS. 1 and 6, the bolt member 54 includes a flanged head portion 54a and a screw shaft portion 54b. The screw shaft portion 54b includes a non-thread portion 55a on the proximal end side, a screw portion 55b on the distal end side, and a small diameter portion 55c between the non-thread portion 55a and the screw portion 55b. Therefore, by configuring the small diameter portion 55c, the weakest strength portion 90 that exhibits a function as described later is configured. In this case, a through hole 56 is provided in the inner wall 22 c, the shaft portion 54 b of the bolt member 54 is inserted into the through hole 56, and the screw portion 55 b is screwed into the screw hole 50 of the shaft portion 12. The non-threaded portion 55 a of the bolt member 54 corresponds to the through hole 56. As shown in FIG. 6, the hole diameter D2 of the through hole 56 is set slightly larger than the outer diameter (shaft diameter) D1 of the non-threaded portion 55a of the shaft portion 54b. Specifically, 0.05 mm <D2−D1 <0.5 mm. The maximum outer diameter of the threaded portion 55c is set to be the same as or slightly smaller than the outer diameter of the large base portion 55a.

  In this wheel bearing device, as shown in FIG. 2, a shaft portion press-fitting guide portion M1 that guides the press-fitting of the shaft portion 12 during press-fitting is provided on the convex portion press-fitting start side. In this case, it consists of a female spline 44 provided in the tapered portion 49 a of the hole portion 22. That is, as shown in FIG. 4 (a), the guide recess 44a has a predetermined pitch (in this case, the same pitch as the arrangement pitch of the protrusions 35) along the circumferential direction on the shaft fitting hole 22a side of the taper 49a. Is provided.

  In this case, as shown in FIG. 6, the bottom diameter D6 of the guide recess 44a is the maximum outer diameter of the projection 35, that is, the maximum diameter of the circle connecting the vertices of the projection 35 which is the projection 41a of the spline 41. (Diameter of circumscribed circle) (shaft outer diameter) D3, and as shown in FIG. 4A, a radial clearance C1 is formed between the top of the convex portion 35 and the bottom of the guide concave portion 44a. Forming.

  Next, the fitting method of the uneven fitting structure M will be described. In this case, as shown in FIG. 6, the outer diameter portion of the shaft portion 12 is subjected to thermosetting treatment, and the spline 41 including the convex portions 41 a and the concave portions 41 b along the axial direction is formed on the hardened layer H. For this reason, the convex part 41a of the spline 41 is cured, and the convex part 41a becomes the convex part 35 of the concave-convex fitting structure M. The spline 41 is provided on the small diameter side of the main body 12 a of the shaft 12. The range of the hardened layer H in this embodiment is from the outer end edge of the spline 41 to a part of the bottom wall of the mouth portion 11 of the outer ring 5 as shown by the cross hatched portion. As this thermosetting treatment, various heat treatments such as induction hardening and carburizing and quenching can be employed. Here, induction hardening is a hardening method that applies the principle of heating a conductive object by placing Joule heat in a coil through which high-frequency current flows, and generating Joule heat by electromagnetic induction. is there. The carburizing and quenching is a method in which carbon is infiltrated / diffused from the surface of the low carbon material and then quenched. The module of the spline 41 of the shaft portion 12 is a small tooth of 0.5 or less. Here, the module is a pitch circle diameter divided by the number of teeth.

  On the inner diameter surface 37 side of the hole portion 22 of the hub wheel 1 (that is, the inner diameter surface of the shaft portion fitting hole 22a), an uncured portion (unburned state) that is not subjected to the thermosetting treatment. The hardness difference between the hardened layer H of the shaft portion 12 of the outer ring 5 and the uncured portion of the hub wheel 1 is 20 points or more in HRC. More specifically, the hardness of the hardened layer H is about 50 HRC to 65 HRC, and the hardness of the uncured portion is about 10 HRC to 30 HRC.

At this time, the intermediate portion in the protruding direction of the convex portion 35 corresponds to the position of the concave portion forming surface (in this case, the inner diameter surface 37 of the shaft portion fitting hole 22a) of the concave portion. That is, as shown in FIG.
The inner diameter dimension (hub ring inner diameter) D4 of the inner diameter surface 37 of the shaft fitting hole 22a is set to the maximum outer diameter of the convex portion 35, that is, the maximum diameter of a circle connecting the apexes of the convex portions 35 which are the convex portions 41a of the spline 41. It is smaller than the dimension (diameter of circumscribed circle) D3, and is set larger than the outer diameter dimension, that is, the maximum diameter dimension D5 of the circle connecting the bottom of the concave portion 41b of the spline 41 to the outer diameter surface of the shaft portion between the convex portions. That is, D5 <D4 <D3. Further, D3 is set smaller than the hole diameter dimension D7 of the large-diameter portion 46 of the hole 22.

  The spline 41 can be formed by various processing methods such as rolling processing, cutting processing, press processing, and drawing processing, which are known publicly known means. Moreover, various heat processing, such as induction hardening and carburizing hardening, can be employ | adopted as a thermosetting process. Note that the press-fitting start end surface 35 a of the convex portion 35 formed by forming the spline 41 is a flat surface orthogonal to the axial direction of the shaft portion 12.

  Then, as shown in FIG. 6, the shaft center of the hub wheel 1 and the shaft center of the outer ring 5 of the constant velocity universal joint 3 are in a combined state. In this state, the shaft portion 12 of the outer ring 5 is inserted (press-fitted) into the hub wheel 1. That is, the projections 35 of the shaft portion 12 are fitted into the guide recesses 44a of the shaft portion press-fitting guide portion M1. Thereby, the axial center of the hub wheel 1 and the axial center of the outer ring 5 are brought into a coincident state. At this time, since the end portion of each guide recess 44a on the uneven fitting structure side is a flat surface 77a (see FIG. 2) orthogonal to the press-fitting direction, the press-fitting start end surface 35a of the convex portion 35 is received. It is possible to press fit from this state. At this time, as described above, the diameter D4 of the inner surface 37 of the shaft fitting hole 22a, the maximum outer diameter D3 of the projection 35, and the maximum outer diameter D5 of the recess of the spline 41 are as described above. Further, since the hardness of the convex portion 35 is 30 points or more larger than the hardness of the inner diameter surface 37, if the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1, the convex portion 35 becomes the inner diameter. The convex portion 35 bites into the surface 37, and the concave portion 36 into which the convex portion 35 is fitted is formed along the axial direction.

  This press-fitting is performed until the back surface 11a of the mouse portion 11 comes into contact with the end surface 31a of the crimping portion 31 of the hub wheel 1. At this time, as shown in FIG. 5, the end surface 52 of the small diameter portion 12b of the shaft portion 12 is maintained in a state where it does not contact the end surface 53 of the inner wall 22c. If it press-fits in this way, as shown to Fig.3 (a) (b), the whole fitting contact site | part 38 of the convex part 35 of the edge part of the axial part 12 and the recessed part 36 fitted to this will be carried out. It is in close contact. In other words, the shape of the convex portion 35 is transferred to the other-side concave portion forming surface (in this case, the inner diameter surface 37 of the shaft portion fitting hole 22a of the hole portion 22). At this time, the convex portion 35 bites into the inner diameter surface 37 of the hole portion 22, so that the hole portion 22 is slightly expanded in diameter, and the convex portion 35 is allowed to move in the axial direction. When the movement stops, the hole 22 is reduced in diameter to return to the original diameter. In other words, the hub wheel 1 is elastically deformed in the radial direction when the convex portion 35 is press-fitted, and a preload corresponding to this elastic deformation is applied to the tooth surface of the convex portion 35 (surface of the concave portion fitting portion). For this reason, the concave / convex fitting structure M in which the entire concave portion fitting portion of the convex portion 35 is in close contact with the corresponding concave portion 36 can be reliably formed. That is, a female spline 42 that closely contacts the male spline 41 is formed on the inner diameter surface of the hole 22 of the hub wheel 1 by the spline (male spline) 41 on the shaft portion 12 side.

  In this way, the concave-convex fitting structure M is configured. In this case, the concave-convex fitting structure M is disposed at a position directly below the raceway surfaces 26, 27, 28, 29 of the rolling bearing 2. Here, the direct under-position is a position that does not correspond to the radial direction with respect to the ball contact portion position of the raceway surfaces 26, 27, 28, and 29.

  After the press-fitting, the bolt member 54 is screwed into the screw hole 50 of the shaft portion 12 from the opposite joint side. Thus, by screwing the bolt member 54 into the screw hole 50 of the shaft portion 12, the flange portion 60 of the head portion 54a of the bolt member 54 is fitted into the recessed portion 51 of the inner wall 22c. As a result, the hub wheel 1 is sandwiched between the head portion 54a of the bolt member 54 and the concave-convex fitting structure M, or between the head portion 54a of the bolt member 54 and the back surface 11a of the mouse portion 11, and the hub wheel 1 and the constant velocity universal joint 3 are integrated. In this manner, the bolt coupling means M5 on the device shaft center where the hub wheel 1 and the shaft portion 12 of the outer ring 5 are coupled is constituted by the bolt member 54 and the screw hole 50 etc. into which the bolt member 54 is screwed. The

  In this case, the diameter difference between the hole diameter D2 of the bolt insertion hole 56 and the shaft diameter D1 of the non-threaded portion 55a of the bolt member 54 is Δd, and the shaft portion outer diameter D3 of the outer ring 5 in the uneven fitting structure M and the uneven fitting structure. When the difference in diameter from the hub wheel inner diameter D4 in M is Δd2, 0 <Δd <Δd2.

  A sealing material (not shown) may be interposed between the seat surface 60a of the bolt member 54 and the inner wall 22c. For example, sealing materials (sealing agents) made of various resins that can be cured after application to the seating surface 60a of the bolt member 54 and exhibit sealing properties between the seating surface 60a and the bottom surface of the recessed portion 51 of the inner wall 22c. What is necessary is just to apply. In addition, as this sealing material, the thing which does not deteriorate in the atmosphere where this wheel bearing apparatus is used is selected. Further, the sealing material may be applied to the inner wall 22c side, or may be applied to the seating surface 60a side and the inner wall 22c side.

  By bringing the crimped portion 31 and the back surface 11a of the mouth portion 11 of the outer ring 5 into contact with each other, the bending rigidity in the axial direction is improved, the bending strength is improved, and a high-quality product excellent in durability is obtained. Become. In addition, positioning at the time of press-fitting can be configured by this contact. As a result, the dimensional accuracy of the wheel bearing device can be stabilized, and the axial length of the concave-convex fitting structure M disposed along the axial direction can be ensured to be stable. Can be improved. Furthermore, a seal structure can be formed by this contact, foreign matter can be prevented from entering the concave-convex fitting structure M from the crimping portion 31 side, and the concave-convex fitting structure M can maintain a stable fitting state for a long period of time.

  Further, a sealing material (sealant) may be interposed between the end surface 31 a of the crimping portion 31 and the back surface 11 a of the mouth portion 11 of the outer ring 5. In this case, a sealing material is applied to the end surface 31a side of the crimping portion 31, a sealing material is applied to the back surface 11a side of the mouth portion 11, and further, applied to the end surface 31a side and the back surface 11a side. can do.

  Since the end portion of the hub wheel 1 is crimped and preload is applied to the bearing 2, it is not necessary to apply preload by the mouth portion 11 of the outer ring 5. For this reason, it is possible to press-fit the shaft portion 12 of the outer ring 5 without considering the preload, and it is possible to improve the connectivity (assembly property) between the hub wheel 1 and the outer ring 5.

  If the contact surface pressure between the caulking portion 31 of the hub wheel 1 and the back surface 11a of the mouse portion 11 exceeds 100 MPa, abnormal noise may be generated. That is, when a large torque load is applied, a difference occurs in the amount of twist between the outer ring 5 of the constant velocity universal joint 3 and the hub wheel 1, and this difference causes a sudden contact between the outer ring 5 of the constant velocity universal joint 3 and the hub wheel 1. Slip occurs and abnormal noise occurs. On the other hand, if the contact surface pressure is 100 MPa or less as in the present invention, it is possible to prevent a sudden slip and to suppress the generation of abnormal noise. Thereby, a quiet wheel bearing device can be configured. Even if the contact surface pressure is 100 MPa or less, it is necessary that the contact surface pressure is not less than the surface pressure that can constitute the seal structure.

  As described above, in the present invention, the concave-convex fitting structure M in which the entire fitting contact portion 38 between the convex portion 35 of the shaft portion 12 and the concave portion 36 of the hub wheel 1 is in close contact can be reliably formed. Moreover, it is not necessary to form a spline portion or the like on the member in which the concave portion 36 is formed, which is excellent in productivity, and does not require the phase alignment between the splines. The tooth surface can be prevented from being damaged, and a stable fitting state can be maintained.

In the concave / convex fitting structure M, the entire fitting contact portion 38 between the convex portion 35 and the concave portion 36 is in close contact with each other. Therefore, in the fitting structure M, there is no gap in which play occurs in the radial direction and the circumferential direction. . For this reason, all the fitting parts contribute to rotational torque transmission, stable torque transmission is possible, and no abnormal noise is generated.

  Since the shaft portion press-fitting guide portion M1 is provided, when the shaft portion 12 is press-fitted into the hole 22 of the hub wheel 1, it can be press-fitted along the shaft portion press-fitting guide portion M1.

  By the way, if the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1, the formed protruding portion 45 is curled while being curled, as shown in FIGS. It is accommodated in a space accommodating portion 57 composed of a space provided on the diameter side. Here, the protruding portion 45 is the material of the capacity of the concave portion 36 into which the convex portion 35 is inserted (fitted), and is extruded from the concave portion 36 to be formed, and is cut to form the concave portion 36. It is comprised from what was extruded, what was extruded, and what was cut. For this reason, the protruding portion 45 which is a part of the material scraped off or pushed out from the inner diameter surface of the hole portion 22 enters the storage portion 57.

  Thus, by providing the storage portion 57 for storing the protruding portion 45 generated by forming the concave portion by the press-fitting, the protruding portion 45 can be held (maintained) in the storage portion 57, and the protruding portion 45 is outside the apparatus. Never get into any other vehicle. That is, the protruding portion 45 can be kept stored in the storage portion 57, and it is not necessary to perform the removal processing of the protruding portion 45, so that the number of assembling operations can be reduced, and the assembly workability can be improved. Cost reduction can be achieved.

  The bolt coupling means M5 restricts the axial direction of the shaft portion 12 from the hub wheel 1 and enables stable torque transmission over a long period of time.

  Since the end of the hub wheel 1 is crimped and preload is applied to the rolling bearing 2, it is not necessary to apply preload by the mouth portion 11 of the outer ring 5. For this reason, it is possible to press-fit the shaft portion 12 of the outer ring 5 without considering the preload to the rolling bearing 2 and to improve the connectivity (assembly property) between the hub wheel 1 and the outer ring 5.

  A sealing material is interposed between the seat surface 60a of the bolt member 54 for fixing the bolt between the hub wheel 1 and the shaft portion 12 of the outer ring 5 and the inner wall 22c, or the end surface 31a of the crimping portion 31 and the mouth portion 11 are By interposing a sealing material between the bottom portion back surface 11a and the like, it is possible to prevent rainwater and foreign matter from entering the concave-convex fitting structure M from the bolt member 54, thereby improving the quality.

  In addition, by arranging the intermediate portion in the protruding direction of the convex portion 35 on the concave portion forming surface before the concave portion is formed, the convex portion 35 bites into the concave portion forming surface during press-fitting, and the concave portion 36 is reliably formed. can do. That is, the press-fitting allowance with respect to the other side of the convex part 35 can be taken sufficiently. As a result, the formability of the concave-convex fitting structure M is stabilized, there is no variation in press-fit load, and a stable torsional strength is obtained.

  In the embodiment shown in FIG. 1 and the like, the convex portion 35 of the concave-convex fitting structure M is provided on the shaft portion 12 of the outer ring 5, and the hardness of the axial end portion of the convex portion 35 is set from the inner diameter portion of the hole portion of the hub wheel 1. If the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1, the hardness on the shaft portion side can be increased and the rigidity of the shaft portion can be improved.

  By arranging the concave-convex fitting structure M at a position directly below the raceway surface of the rolling bearing 2, occurrence of hoop stress on the bearing raceway surface is suppressed. As a result, it is possible to prevent a bearing failure such as a decrease in rolling fatigue life, occurrence of cracks, and stress corrosion cracking, and a high-quality bearing 2 can be provided.

  As in the above-described embodiment, the spline 41 formed on the shaft portion 12 uses small teeth with a module of 0.5 or less, so that the formability of the spline 41 can be improved and the press-fit load is reduced. Can be achieved. In addition, since the convex part 35 can be comprised with the spline normally formed in this kind of shaft, this convex part 35 can be easily formed at low cost.

  By the way, the outer ring 5 can be pulled out from the hub wheel 1 by removing the bolt member 54 by screwing the bolt member 54 out of the state shown in FIG. That is, the fitting force of the concave-convex fitting structure M can be pulled out by applying a pulling force of a predetermined force or more to the outer ring 5.

  For example, the hub wheel 1 and the constant velocity universal joint 3 can be separated by a jig 70 as shown in FIG. The jig 70 includes a base 71, a pressing bolt member 73 that is screwed into a screw hole 72 of the base 71 so as to be able to advance and retreat, and a screw shaft 76 that is screwed into the screw hole 50 of the shaft portion 12. A through hole 74 is provided in the base 71, and the bolt 33 of the hub wheel 1 is inserted into the through hole 74, and the nut member 75 is screwed into the bolt 33. At this time, the base 71 and the flange 21 of the hub wheel 1 are overlapped, and the base 71 is attached to the hub wheel 1.

  Thus, after attaching the base 71 to the hub wheel 1 or before attaching the base 71, the screw shaft 76 is screwed into the screw hole 50 of the shaft portion 12 so that the base portion 76a protrudes from the inner wall 22c to the anti-joint side. Combine. The protruding amount of the base portion 76a is set longer than the axial length of the uneven fitting structure M. The screw shaft 76 and the pressing bolt member 73 are disposed on the same axis (on the axis of this wheel bearing device).

  Thereafter, the pressing bolt member 73 is screwed into the screw hole 72 of the base 71 from the opposite joint side, and in this state, is screwed to the screw shaft 76 side as indicated by an arrow. At this time, since the screw shaft 76 and the pressing bolt member 73 are arranged on the same axis (on the axis of the wheel bearing device), the screw bolt 73 is caused by this screwing. The screw shaft 76 is pressed in the direction of the arrow. As a result, the outer ring 5 moves in the direction of the arrow with respect to the hub ring 1, and the outer ring 5 is detached from the hub ring 1.

  Further, from the state in which the outer ring 5 is detached from the hub wheel 1, the hub wheel 1 and the outer ring 5 can be connected again using, for example, the bolt member 54. That is, with the base 71 removed from the hub wheel 1 and the screw shaft 76 removed from the shaft 12, the projection 35 of the shaft 12 is fitted into the guide recess 44a as shown in FIG. Let Thereby, the phase of the male spline 41 on the shaft portion 12 side and the female spline 42 of the hub wheel 1 formed by the previous press-fitting match. At this time, as shown in FIG. 4A, a radial gap C1 is formed between the top of the projection 35 and the bottom of the guide recess 44a.

  In this state, as shown in FIG. 9, the bolt member 54 is screwed into the screw hole 50 of the shaft portion 12 through the through hole 56, and the bolt member 54 is screwed into the screw hole 50. Thereby, as shown in FIG. 10B, the shaft portion 12 is fitted into the hub wheel 1. At this time, the hole 22 is slightly expanded in diameter, allowing the axial portion 12 to enter in the axial direction, and the back surface 11 a of the mouth portion 11 of the outer ring 5 abuts on the end surface 31 a of the caulking portion 31. Invade until. In this case, at the same time, as shown in FIG. 10C, the end surface 35 a of the convex portion 35 comes into contact with the end surface 36 a of the concave portion 36. If the movement in the axial direction is stopped, the hole 22 is reduced in diameter to return to the original diameter. As a result, as in the previous press-fitting, the concave-convex fitting structure M in which the entire concave portion fitting portion of the convex portion 35 is in close contact with the corresponding concave portion 36 can be reliably configured.

  Since the opening portion of the screw hole 50 of the shaft portion 12 is a tapered portion 50a that expands toward the opening side, there is an advantage that the screw shaft 76 and the bolt member 54 can be easily screwed into the screw hole 50.

  By the way, in the first time (press-fitting to form the recess 36 in the inner diameter surface 37 of the hole 22), the press-fitting load is relatively large. On the other hand, in such re-pressing, since the press-fitting load is smaller than the first press-fitting load, the shaft portion 12 can be stably and accurately inserted into the hole of the hub wheel 1 without using a press machine or the like. 22 can be press-fitted. For this reason, the outer ring 5 and the hub wheel 1 can be separated and connected in the field.

  Moreover, the difference in diameter between the hole diameter D2 of the bolt insertion hole 56 and the shaft diameter D1 of the non-threaded portion 55a of the bolt member 54 is Δd, and the shaft portion outer diameter D3 of the outer ring 5 and the uneven fitting structure M in the uneven fitting structure M. When the diameter difference from the hub wheel inner diameter D4 is Δd2, 0 <Δd <Δd2. For this reason, the difference in diameter between the hole diameter D2 of the bolt insertion hole 56 and the shaft diameter D1 of the non-threaded portion 55a of the bolt member 54 is the difference between the shaft portion outer diameter D3 of the outer ring 5 and the hub wheel inner diameter D4 in the concave-convex fitting structure M. The bolt insertion hole 56 becomes the shaft portion press-fitting guide structure portion M3 when the shaft portion 12 of the outer ring 5 is re-pressed. That is, the bolt coupling means M5 includes the shaft portion press-fitting guide structure portion M3, and the press-fitting is guided to the shaft portion by the shaft portion press-fitting guide structure portion M3 without being misaligned during re-press fitting. For this reason, stable re-press fitting is possible, and the convex portion 35 is fitted into the concave portion 36 formed previously without being displaced, so that the reassembly can be improved.

  At the time of re-pressing, it may be press-fitted in a direction inclined with respect to the misalignment or the device axis. In such a case, an excessive load (excessive axial force) is applied to the bolt member 54, and the misalignment or oblique fitting of the uneven fitting structure M occurs. For this reason, the concave-convex fitting structure M is damaged, or the entire fitting contact portion 38 between the convex portion 35 and the concave portion 36 cannot be adhered. For this reason, in the present invention, the bolt member 54 is provided with the weakest strength portion 90 so that the bolt member 54 is preliminarily damaged when an excessive axial force is generated. An excessive axial force that causes the bolt member 54 to be damaged in advance can be arbitrarily set by setting the diameter dimension and the length dimension of the weakest strength portion 90. Therefore, the weakest strength portion 90 is preliminarily damaged within a range in which the uneven fitting structure M is damaged or a load is applied to the extent that the entire fitting contact portion 38 between the convex portion 35 and the concave portion 36 cannot be brought into close contact. Can be set as follows.

  For this reason, when an excessive load (excessive axial force) is applied to the bolt member 54 at the time of re-pressing, the strength weakest portion 90 is damaged. For this reason, in the misalignment state where an excessive axial force is applied, the bolt member 54 is damaged, and the concave / convex fitting structure M is damaged, or the fitting contact portion between the convex portion 35 and the concave portion 36 is damaged. It is possible to prevent the adhesion of 38 from being lowered.

  Thus, in the present invention, the outer ring 5 can be removed from the hole 22 of the hub wheel 1 by applying an axial pulling force to the shaft part 12 of the outer ring 5, so that repair and inspection of each part can be performed. The workability (maintenance) can be improved. Moreover, after each part is repaired and inspected, it can be press-fitted by bolt fastening by the bolt coupling means M5, and the workability can be improved. In particular, in a misalignment state in which an excessive axial force is applied, the bolt member 54 is damaged, and the concave / convex fitting structure M is damaged, or the fitting contact portion 38 between the convex portion 35 and the concave portion 36. It is possible to prevent the adhesion of the resin from being lowered. For this reason, also in the re-pressing process, the uneven | corrugated fitting structure M which the fitting contact site | part whole region of the convex part 35 and the recessed part 36 closely_contact | adhere can be comprised, and the wheel bearing apparatus in which stable torque transmission is possible again Can be configured.

  The shaft press-fitting guide portion M1 has a guide recess 44a (shaft press-fit guide portion M1) that matches the phase of the convex portion 35 with the phase of the other concave portion 36. When the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1, the shaft portion 12 is fitted into the concave portion 36 formed by the previous press-fitting, and the concave portion 36 is not damaged. For this reason, the uneven | corrugated fitting structure M which does not produce the clearance gap which produces backlash in a radial direction and the circumferential direction again can be comprised with high precision.

  By forming a gap between the top of the projection 35 and the bottom of the guide recess 44a, etc., the projection 35 can be easily fitted into the guide recess 44a in the pre-press-in process, and the guide recess 44a does not hinder the press-fitting of the convex portion 35. For this reason, the assemblability can be improved.

In addition, if the axial length of the through hole 56 is too short, a stable guide cannot be exhibited. On the contrary, if it is too long, the thickness dimension of the inner wall 22c becomes large, and the shaft of the concave-convex fitting structure M The length in the direction cannot be secured, and the weight of the hub wheel 1 is increased. Therefore, various changes can be made in consideration of these.

  In the embodiment, as shown in FIG. 4A, the radial gap C1 is formed between the top of the projection 35 and the bottom of the guide recess 44a, but as shown in FIG. 4B. In addition, circumferential gaps C2 and C2 may be formed between the side portion of the convex portion 35 and the side portion of the guide concave portion 44a. Further, as shown in FIG. 4C, the radial gap C1 between the top of the convex portion 35 and the bottom of the guide concave portion 44a, and the side portion of the convex portion 35 and the side portion of the guide concave portion 44a. A circumferential clearance C2 may be formed between them. By forming such a gap, the protrusion 35 can be easily fitted into the guide recess 44a in the pre-press-in process, and the guide recess 44a does not prevent the protrusion 35 from being press-fitted.

  In the spline 41 shown in FIG. 2, the pitch of the convex portions 41a and the pitch of the concave portions 41b are set to be the same. For this reason, in the said embodiment, as shown in FIG.2 (b), it respond | corresponds to the circumferential direction thickness L of the protrusion direction intermediate part of the convex part 35, and the said intermediate part between the convex parts 35 adjacent to the circumferential direction. The circumferential dimension L0 at the position is substantially the same.

  On the other hand, as shown in FIG. 11A, the circumferential thickness L2 of the projecting direction intermediate portion of the convex portion 35 is set at a position corresponding to the intermediate portion between the convex portions 35 adjacent in the circumferential direction. It may be smaller than the circumferential dimension L1. That is, in the spline 41 formed on the shaft portion 12, the circumferential thickness (tooth thickness) L <b> 2 of the intermediate portion in the projecting direction of the convex portion 35 is set to the height of the convex portion 43 on the hub wheel 1 side fitted between the convex portions 35. It is made smaller than the circumferential thickness (tooth thickness) L1 of the intermediate portion in the protruding direction.

  Therefore, the total tooth thickness Σ (B1 + B2 + B3 +...) Of the convex portion 35 on the entire circumference on the shaft 12 side is replaced by the total tooth thickness Σ (A1 + A2 + A3 +) of the convex portion 43 (convex tooth) on the hub wheel 1 side.・ It is set smaller than. As a result, the shear area of the convex portion 43 on the hub wheel 1 side can be increased, and the torsional strength can be ensured. And since the tooth thickness of the convex part 35 is small, a press-fit load can be made small and a press-fit property can be aimed at. When making the sum total of the circumferential thickness of the convex part 35 smaller than the sum total of the circumferential direction thickness in the other convex part 43, the circumferential direction thickness L2 of all the convex parts 35 is the convex part adjacent to the circumferential direction. It is not necessary to make it smaller than the circumferential dimension L1 between 35. That is, among the plurality of convex portions 35, even if the circumferential thickness of the arbitrary convex portion 35 is the same as the circumferential dimension between the convex portions adjacent in the circumferential direction, it is larger than the circumferential dimension. However, it is sufficient if the sum is small.

  In addition, although the convex part 35 in Fig.11 (a) is made into the trapezoid cross section (Mt. Fuji shape), as a shape of the convex part 35, as shown in FIG.11 (b), an involute tooth shape may be sufficient.

  The shaft press-fitting guide portion M1 may be as shown in FIG. In FIG. 12 (a), the end of the guide recess 44a on the concave-convex fitting structure M side is an inclined surface 77b that is inclined to reduce the diameter along the press-fit direction (press-fit progress direction). That is, the inclination angle θ of the inclined surface 77b is, for example, about 45 °.

  12 (b) and 12 (c), the radial depth dimension of the guide recess 44a is reduced along the press-fitting direction. In FIG. 12B, the end portion on the concave-convex fitting structure M side is a flat surface 77a orthogonal to the press-fitting direction, and in FIG. 12C, the end portion on the concave-convex fitting structure M side is the press-fitting direction (press-fit). The inclined surface 77b is inclined along the traveling direction.

  If the end of the guide recess 44a on the uneven fitting structure side is a flat surface 77a orthogonal to the press-fitting direction, the shaft 12 is received by the flat surface 77a when the shaft 12 is press-fitted into the hole 22. be able to. Moreover, if it is the inclined surface 77b, the convex part 35 can be stably inserted from the recessed part 44a for a guide to the recessed part 36 of the other party. Even if the radial depth of the guide concave portion 44a is reduced along the press-fitting direction, the convex portion 35 can be stably fitted from the guide concave portion 44a to the counterpart concave portion 36.

  FIG. 13 shows a modification of the bolt member 54. In the bolt member 54 shown in FIG. 13A, the shaft portion 54b has a non-threaded portion 55a and a threaded portion 55b. A notch flat portion 55d is provided across the bridge. For this reason, the notch flat portion 55d becomes the weakest strength portion 90. The cutout flat portion 55d may be provided only on either the non-threaded portion 55a or the threaded portion 55b. In the bolt member 54 shown in FIG. 13B, the shaft portion 54b has a non-threaded portion 55a and a threaded portion 55b, and a circumferential groove 55e is provided between the non-threaded portion 55a and the head portion 54a. For this reason, the circumferential groove 55e becomes the weakest strength portion 90. In the bolt member 54 shown in FIG. 13C, a through hole 55f perpendicular to the axial direction is provided in the non-threaded portion 55a in the bolt member 54 shown in FIG. 13B. Therefore, the circumferential groove 55e and the through hole 55f become the weakest strength portion 90.

  Next, FIG. 14 shows a second embodiment. In this case, the hub wheel 1 is not provided with the inner wall 22c, and the ring body 80 is mounted in the hole 22 of the hub wheel 1 instead of the inner wall 22c. That is, a ring fitting notch 81 is provided in the hole 22 of the hub wheel 1, and the ring body 80 is fitted to the ring fitting notch 81. At this time, the ring body 80 is engaged with the notch end surface 81 a of the ring fitting notch 81. A bolt insertion hole 82 through which the bolt member 54 is inserted is formed in the ring body 80.

  Also in this case, the bolt member 54 having the weakest strength portion 90 is used. In the illustrated example, the bolt member 54 shown in FIG. 1 is used. Further, as in the first embodiment, the diameter difference Δd between the hole diameter D2 of the bolt insertion hole 82 and the shaft diameter D1 of the non-threaded portion 55a of the bolt member 54 is used. When the diameter difference between D3 and the hub wheel inner diameter D4 in the concave-convex fitting structure M is Δd2, 0 <Δd <Δd2.

  Other configurations of the wheel bearing device shown in FIG. 14 are the same as those of the wheel bearing device shown in FIG. 1, and therefore, the same members as those in FIG. .

  For this reason, even if it is a wheel bearing apparatus shown in FIG. 14, there exists an effect similar to the wheel bearing apparatus shown in FIG. Moreover, since the bolt insertion hole 82 is formed in the ring body 80 which is a separate member from the hub wheel 1, the bolt insertion hole 82 can be stably formed with high accuracy. Further, even when the ring body 80 is damaged or the like, it can be replaced, and it is not necessary to replace the entire hub wheel 1, so that the cost can be reduced.

  By the way, in each said embodiment, while forming the spline 41 which comprises the convex part 35 in the axial part 12 side, the hardening process is performed with respect to the spline 41 of this axial part 12, and the internal diameter surface of the hub ring 1 is unhardened. (Raw material). On the other hand, as shown in FIG. 15, while forming the spline 61 (consisting of the convex stripes 61a and the concave stripes 61b) on the inner diameter surface of the hole portion 22 of the hub wheel 1, the shaft portion 12 may not be subjected to a curing treatment. The spline 61 can also be formed by various processing methods such as broaching, cutting, pressing, and drawing, which are publicly known means. Further, various heat treatments such as induction hardening and carburizing and quenching can be employed as the thermosetting treatment.

  In this case, the intermediate portion in the protruding direction of the convex portion 35 corresponds to the position of the concave portion forming surface (the outer diameter surface of the shaft portion 12) before the concave portion is formed. That is, the diameter dimension (minimum diameter dimension of the convex portion 35) D8 connecting the vertices of the convex portion 35 which is the convex portion 61a of the spline 61 is smaller than the outer diameter size D10 of the shaft portion 12, and the concave portion 61b of the spline 61 is formed. The diameter dimension (inner diameter dimension of the inner diameter surface of the fitting hole between the convex portions) D9 is set larger than the outer diameter dimension D10 of the shaft portion 12. That is, D8 <D10 <D9.

  If the shaft portion 12 is press-fitted into the hole portion 22 of the hub wheel 1, the concave portion 36 into which the convex portion 35 is fitted can be formed on the outer peripheral surface of the shaft portion 12 by the convex portion 35 on the hub wheel 1 side. Thereby, the whole fitting contact part 38 of the convex part 35 and the recessed part fitted to this is closely_contact | adhered.

  Here, the fitting contact portion 38 is a range B shown in FIG. 15B, and is a range from the middle of the mountain shape to the top of the mountain in the cross section of the convex portion 35. Further, a gap 62 is formed on the outer diameter side of the outer peripheral surface of the shaft portion 12 between the adjacent convex portions 35 in the circumferential direction.

  Even in the case shown in FIG. 15, it is preferable to provide the shaft portion press-fitting guide portion M1. In this case, a guide recess may be provided on the shaft 12 side. Further, a radial gap C1 is formed between the top of the convex portion 35 and the bottom of the guide concave portion 44a, or a circumferential gap C2 between the side portion of the convex portion 35 and the side portion of the guide concave portion 44a, C2 can be formed, and further, the radial gap C1 and the circumferential gaps C2 and C2 can be formed.

  Even in the case shown in FIG. 15, since the protruding portion 45 is formed by press-fitting, it is preferable to provide a storage portion 57 for storing the protruding portion 45. Since the protruding portion 45 is formed on the mouse side of the shaft portion 12, the storage portion is provided on the hub wheel 1 side.

  As described above, the convex portion 35 of the concave-convex fitting structure M is provided on the inner diameter surface 37 of the hole portion 22 of the hub wheel 1, and the hardness of the axial end portion of the convex portion 35 is set to the outer diameter of the shaft portion 12 of the outer ring 5. In the case of press-fitting higher than the portion, it is not necessary to perform the hardness treatment (heat treatment) on the shaft portion side, so that the productivity of the outer joint member (outer ring 5) of the constant velocity universal joint is excellent.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, as the shape of the convex portion 35 of the concave and convex fitting structure M, FIG. In the embodiment shown in FIG. 2, the cross section is triangular, and in the embodiment shown in FIG. 11A, the cross section is trapezoidal (mountain shape), but other shapes such as a semicircular shape, a semielliptical shape, and a rectangular shape are available. The area of the convex part 35, the number, the circumferential arrangement pitch, and the like can be arbitrarily changed. That is, it is not necessary to form the spline 41, and the convex portion (convex tooth) 41a of the spline 41 to be the convex portion 35 of the concave-convex fitting structure M, and it may be a key or a curved wave. It may form a mating surface of the mold. In short, the convex portion 35 disposed along the axial direction can be press-fitted into the mating side, and the concave portion 36 can be formed on the mating side with the convex portion 35 so as to closely fit the convex portion 35. It is only necessary that the entire fitting contact portion 38 between the portion 35 and the concave portion fitted thereto is in close contact, and that rotational torque can be transmitted between the hub wheel 1 and the constant velocity universal joint 3.

  The hole portion 22 of the hub wheel 1 may be a deformed hole such as a polygonal hole other than a circular hole, and the cross-sectional shape of the end of the shaft portion 12 fitted into the hole 22 is also a polygon other than a circular cross section. It may be an irregular cross section. Furthermore, since only the press-fitting start end portion of the convex portion 35 needs to be harder than the portion where the concave portion 36 is formed when the shaft portion 12 is press-fitted into the hub wheel 1, it is necessary to increase the overall hardness of the convex portion 35. There is no. Although the gap 40 is formed in FIG. 3 and the like, the gap 40 between the convex portions 35 may bite into the inner diameter surface 37 of the hub wheel 1. Note that the hardness difference between the convex portion 35 side and the concave portion forming surface side formed by the convex portion 35 is preferably 20 points or more in HRC, but 20 points if the convex portion 35 can be press-fitted. It may be less.

  Although the end surface (press-fit start end) of the convex portion 35 is a surface orthogonal to the axial direction in the embodiment, it may be inclined at a predetermined angle with respect to the axial direction. In this case, it may be inclined from the inner diameter side toward the outer diameter side toward the anti-convex portion side or inclined toward the convex portion side.

  Furthermore, you may provide the small recessed part arrange | positioned by the predetermined pitch along the circumferential direction in the internal diameter surface 37 of the hole 22 of the hub wheel 1. FIG. The small recess needs to be smaller than the volume of the recess 36. By providing such a small recess, the press-fit property of the protrusion 35 can be improved. That is, by providing the small concave portion, the capacity of the protruding portion 45 formed when the convex portion 35 is press-fitted can be reduced, and the press-fit resistance can be reduced. Moreover, since the protrusion part 45 can be decreased, the volume of the storage part 57 can be reduced, and the workability of the storage part 57 and the strength of the shaft part 12 can be improved. Various shapes such as a semi-elliptical shape and a rectangular shape can be adopted as the shape of the small recess, and the number can be arbitrarily set.

  As shown in FIG. 13A, when the weakest strength portion 90 is constituted by the cutout flat surface 55d, a plurality of cutout flat surfaces 55d may be arranged at a predetermined pitch along the circumferential direction. . Moreover, as shown in FIG.13 (c), also when comprised by the through-hole 55f, the number of the through-holes 55f provided is arbitrary. In FIG. 13C, the circumferential groove 55e and the through hole 55f are provided. However, when the through hole 55f is provided, the circumferential groove 55e may be omitted, and the through hole 55f and the notched flat surface may be provided. 55d may be combined. The position where the weakest strength portion 90 is provided may be a position that does not hinder the screwing of the shaft portion 12 of the bolt member 54 into the screw hole 50.

  A roller may be used as the rolling element 30 of the bearing 2. In the above-described embodiment, the third generation wheel bearing device is shown, but the first generation or the second generation may be used. In addition, when press-fitting the convex portion 35, even if the side where the concave portion 36 is formed is fixed and the side where the convex portion 35 is formed is moved, the side where the convex portion 35 is formed is reversed. It may be fixed and the side where the recess 36 is formed may be moved or both may be moved. In the constant velocity universal joint 3, the inner ring 6 and the shaft 10 may be integrated via the concave / convex fitting structure M described in the above embodiments.

  If the seating surface 60a of the bolt member 54 and the bottom surface of the recessed portion 51 of the inner wall 22c are excellent in adhesion, such a sealing material can be omitted. That is, it is possible to improve the adhesiveness of the bolt member 54 with the seating surface 60a by grinding the bottom surface of the recessed portion 51. Of course, the sealing material can be omitted if the adhesiveness can be exhibited even in a so-called turning finished state without grinding the bottom surface of the recessed portion 51. Similarly, a sealing material (sealant) may be omitted between the end surface 31 a of the crimping portion 31 and the back surface 11 a of the mouth portion 11 of the outer ring 5.

  As shown in FIGS. 4A, 4B, and 4C, the guide recesses 44a are formed with gaps C1 and C2 between the protrusions 35. It is only necessary that the misalignment or the tilt of the core does not occur at the time of press-fitting, and the convex part 35 presses against the inner surface of the guide concave part 44a so as not to increase the press-fitting load. Further, the axial length of the guide recess 44a can be arbitrarily set, and if it is long, it is preferable for alignment, but the upper limit is limited by the axial length of the hole 22 of the hub wheel 1. On the contrary, if the axial length of the hole 22 of the hub wheel 1 is short, the hub wheel 1 may not function as a guide and may cause misalignment or tilt. For this reason, it is necessary to determine the axial length of the guide recess 44a in consideration of these.

  Moreover, the cross-sectional shape of the guide recess 44a is not limited to that shown in FIG. Various changes can be made according to the cross-sectional shape and the like of the convex portion 35. The number of guide recesses 44a may be smaller or larger than the number of projections 35 without matching the number of projections 35. In short, it is only necessary that some convex portions 35 are fitted in some guide concave portions 44a so that the phase of the convex portions 35 coincides with the phase of the concave portion 36 formed by the previous press-fitting.

  The inclination angle θ of the inclined surface 77b at the end of the guide recess 44a and the inclination angle θ1 of the bottom of the guide recess 44a can be arbitrarily changed. If the inclination angle θ of the inclined surface 77b is close to 90 °, it is functionally the same as the flat surface 77a orthogonal to the press-fitting direction. If the inclination angle θ is small, the guide recess 44a becomes longer, and the concave-convex fitting structure M The axial length of is shortened. Moreover, if the inclination | tilt angle (theta) 1 of a bottom part becomes large, the structure of the recessed part 44a for guides will become difficult, and if it is small conversely, the function in the case of making it incline cannot be exhibited. For this reason, it is necessary to set the inclination angles θ and θ1 in consideration of these.

  By the way, in each said embodiment, in the state which integrated the hub wheel 1 and the outer ring | wheel 5 of the constant velocity universal joint 3, as shown in FIG. 5 etc., the end surface of the small diameter part 12b of the axial part 12 of the outer ring | wheel 5 52 and the end surface 53 of the inner wall 22c are not in contact with each other, but the end surface 52 of the outer ring 5 and the end surface 53 of the inner wall 22c may be in contact (contact). Thus, the positioning of the shaft portion 12 of the outer ring 5 can be configured by abutting (contacting). That is, by positioning, the dimensional accuracy of the wheel bearing device is stabilized, and the axial length of the concave-convex fitting structure M arranged along the axial direction can be secured to a stable length. Thus, torque transmission can be improved. In addition, there is an advantage that it is easy to adjust the contact surface pressure between the caulking portion 31 and the opposing surface of the outer ring 5 (the back surface 11a of the mouse portion 11), the desired contact surface pressure can be maintained, and the noise prevention performance is improved. Can be achieved.

  Although the outer member 25 of the rolling bearing 2 in the above embodiment does not have a vehicle body mounting flange, the outer member 25 may have a vehicle body mounting flange.

It is a longitudinal cross-sectional view of the wheel bearing apparatus which shows 1st Embodiment of this invention. It is an expanded longitudinal cross-sectional view of the said uneven | corrugated fitting structure. The uneven | corrugated fitting structure of the said wheel bearing apparatus is shown, (a) is the ZZ sectional view taken on the line of FIG. 2, (b) is the X section enlarged view of (a). The shaft part press-fit guide structure of the said wheel bearing apparatus is shown, (a) is the WW sectional view of FIG. 2, (b) is an expanded sectional view which shows the 1st modification of a shaft part press-fit guide structure. (C) is an expanded sectional view which shows the 2nd modification of an axial part press-fit guide structure. It is a principal part enlarged view of the said wheel bearing apparatus. It is sectional drawing which shows the decomposition | disassembly state of the said wheel bearing apparatus. It is sectional drawing which shows the isolation | separation method of an uneven | corrugated fitting structure. It is sectional drawing which shows the repressing method. It is sectional drawing which shows the repressing method. The re-pressing method is shown, (a) is a cross-sectional view showing a state immediately before press-fitting, (b) is a cross-sectional view showing the press-fitting process, and (c) is a cross-sectional view showing a press-fitting completion state. It is sectional drawing which shows the modification of an uneven | corrugated fitting structure. The shaft part press fit guide structure is shown, (a) is a sectional view of the first modification, (b) is a sectional view of the second modification, and (c) is a sectional view of the third modification. The modification of a bolt member is shown, (a) is a side view of the 1st modification, (b) is a side view of the 1st modification, and (c) is a side view of the 1st modification. It is a longitudinal cross-sectional view of the wheel bearing apparatus which shows 2nd Embodiment of this invention. The wheel bearing apparatus which shows 3rd Embodiment of this invention is shown, (a) is a cross-sectional view. (B) is the Y section enlarged view of (a). It is sectional drawing of the conventional wheel bearing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hub wheel 2 Bearing 3 Constant velocity universal joint 11 Mouse | mouth part 11a Back surface (bottom part back surface)
12 Shaft portion 22 Hole portion 24 Inner ring 25 Outer member 31 Caulking portion 35 Protruding portion 36 Recessing portion 37 Inner diameter surface 38 Fitting contact portion 50 Screw hole 54 Bolt member 60a Seat surface 90 Low strength portion M Concavity and convexity fitting structure M1 Shaft portion Press-fit guide

Claims (10)

A hub wheel having a flange for mounting to the wheel, the rolling bearing of the double row, with and a constant velocity universal joint having an outer joint member are unitized, is fitted with the hub wheel, the hole of the hub wheel A wheel bearing device in which the shaft portion of the outer joint member is detachably coupled via the concave-convex fitting structure,
A convex portion extending in the axial direction provided on either the outer diameter surface of the shaft portion of the outer joint member or the inner diameter surface of the hole portion of the hub wheel is press-fitted into the other along the axial direction, and the convex portion on the other side. Forming the concave portion that closely fits into the other by forming the convex portion into the other , forming the concave-convex fitting structure in which the entire fitting contact portion between the convex portion and the concave portion is in close contact,
In the state where the concave-convex fitting structure is configured , the hub wheel and the shaft portion of the outer joint member include a screw hole provided at an end portion of the shaft portion of the outer joint member and a bolt member screwed into the screw hole. is fixed through a bolt coupling means on the axis having,
The uneven fitting structure is allowed to be separated by applying an axial pulling force after removing the bolt member,
Reinject into the recess of the convex portions after the separation of the recess-projection fitting structure is carried out by tightening the bolt member, the strength weakest portion in the bolt member is provided with, this strength weakest part, upon the re-press-fitting A bearing device for a wheel, characterized in that the weakest strength portion is set to a strength that causes prior breakage due to an excessive axial force generated with tightening of the bolt member . The wheel bearing device according to claim 1, wherein a shaft press-fitting guide portion of the outer joint member is provided on a convex press-fitting start side. The outer joint member includes a mouth portion in which the inner joint member is housed, and the shaft portion protruding from the bottom portion of the mouth portion, and an end portion of the hub wheel is crimped at the crimped portion. 3. An inner ring of a rolling bearing that is externally fitted to a hub ring is fixed, and a caulking portion is brought into contact with an opposing surface of an outer joint member facing the same. The wheel bearing device described. At least one of the caulking portion of the hub wheel and the opposing surface of the outer joint member facing the hub ring, or the seat surface of the bolt member of the bolt coupling means and the receiving surface receiving the seat surface. The wheel bearing device according to any one of claims 1 to 3, wherein a sealing material is interposed in the wheel bearing device. A convex portion of the concave-convex fitting structure is provided on the shaft portion of the outer joint member, and at least the hardness of the axial end portion of the convex portion is made higher than the inner diameter portion of the hole portion of the hub wheel so that the shaft portion is the hub wheel. By press-fitting into the hole portion of the convex portion from the axial end portion side, a concave portion that closely fits to the convex portion is formed on the inner diameter surface of the hole portion of the hub wheel at the convex portion, and the concave-convex fitting structure is formed. The wheel bearing device according to any one of claims 1 to 4, wherein the wheel bearing device is configured. The inner diameter dimension of the inner diameter surface of the hole portion of the hub ring is smaller than the maximum diameter dimension of the arc connecting the vertices of the plurality of convex portions provided on the shaft portion of the outer joint member, and the concave portions between the convex portions of the shaft portion are connected. The wheel bearing device according to claim 5, wherein the wheel bearing device is set larger than a maximum diameter dimension of the arc. A convex portion of the concave-convex fitting structure is provided on the inner diameter surface of the hole portion of the hub wheel, and at least the hardness of the axial end portion of the convex portion is higher than the outer diameter portion of the shaft portion of the outer joint member of the constant velocity universal joint. The convex portion on the hub wheel side is press-fitted into the shaft portion of the outer joint member from the axial end side thereof, so that the convex portion is formed on the outer diameter surface of the shaft portion of the outer joint member. The wheel bearing device according to any one of claims 1 to 4, wherein the concave and convex fitting structure is formed by forming a concave portion to be closely fitted. The outer diameter dimension of the shaft portion of the outer joint member is made larger than the minimum diameter dimension of the arc connecting the vertices of the plurality of convex portions provided in the hole portion of the hub wheel, and the concave portion between the convex portions of the hub ring hole portion. The wheel bearing device according to claim 7, wherein the wheel bearing device is set to be smaller than a minimum diameter dimension of an arc connecting the two. The sum of the circumferential thicknesses of the projecting direction intermediate portions of the convex portions is the sum of the circumferential thicknesses at positions corresponding to the intermediate portions of the mating convex portions that fit between the convex portions adjacent in the circumferential direction. The wheel bearing device according to any one of claims 1 to 8, wherein the wheel bearing device is also made smaller. The wheel bearing device according to any one of claims 1 to 9, wherein the concave-convex fitting structure is arranged at a position directly below the raceway surface of the rolling bearing.

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