JP4205752B2 - Wheel bearing device - Google Patents

Description

  The present invention relates to a wheel bearing device that rotatably supports a wheel of an automobile or the like.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like is such that a hub wheel for mounting a wheel is rotatably supported via a rolling bearing, and there are a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. As the wheel bearing device, a double-row angular ball bearing having a desired bearing rigidity, exhibiting durability against misalignment, and having a small rotational torque from the viewpoint of improving fuel efficiency is often used.

  The bearing includes an inner member having a rolling surface formed on the outer side, an outer member having a rolling surface formed on the inner side, and a rolling element that is arranged to freely roll between both rolling surfaces. Become. Conventionally, the inner member and the outer member are formed by turning or the like, but a method of press-molding the inner member and the outer member from a plate material or a pipe material has been devised with the aim of reducing the weight and cost. .

Patent Document 1 and Patent Document 2 show examples in which the inner member and the outer member are formed of a plate material or a pipe material. In Patent Document 1, the inner member is composed of a pair of inner rings, and a ball is rotatably disposed between the inner ring and the outer member. In this example, a preload is applied by placing a weight on the inner ring from the axial direction. Further, in Patent Document 2, double rows of balls are arranged in an annular shape at the annular curved portion of the inner member, and an annular recess is formed in the outer member by a hydraulic press roller. A preload is applied between the inner member, the outer member, and the ball during the press forming.
Japanese Utility Model Publication No. 6-1835 Japanese Patent Laid-Open No. 1-210612

  However, when muddy water or the like is applied to the wheel bearing devices shown in Patent Document 1 and Patent Document 2, the muddy water or the like enters the bearing from the gap between the inner member and the outer member, and adversely affects the life of the bearing. give. Also, the lubricating grease sealed inside the bearing may leak and adversely affect the life of the bearing.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a long-life wheel bearing device that prevents muddy water and the like from entering the bearing.

According to an aspect of the present invention, a pair of an outer ring rolling surface of the double row on the inner peripheral surface is formed, the inner rolling run surface opposed to the outer rolling run side of double row outer periphery is formed An inner ring and a double-row rolling element accommodated so as to be freely rollable between both rolling surfaces, and the outer ring and the inner ring are formed by pressing or rolling from a plate material or a pipe material, The outer ring has a cylindrical portion and a recessed portion formed at the center of the cylindrical portion and having an outer periphery recessed toward the inner diameter side, and a radially inner side on the inner peripheral side corresponding to the recessed portion on the inner peripheral surface. An annular projecting portion is formed on the inner circumferential surface on both sides of the annular projecting portion, and the outer circumferential rolling surface of the double row is formed on both sides of the annular projecting portion. Is formed, the thickness of the cylindrical portion is thinner than the thickness of the portion where the outer rolling surface is formed, the pair of inner rings, The shapes are arranged symmetrically with no gap between them, and a first cylindrical portion extending in the axial direction and an inner rolling surface connected to the first cylindrical portion are respectively formed from the butted portion. A second cylindrical portion extending in the axial direction is formed on a different side of the inner rolling surface from the first cylindrical portion, and the inner peripheral surface of the second cylindrical portion is the first cylinder. And the height of the outer diameter surface of the second cylindrical portion with respect to the inner rolling surface of the inner ring is larger than the inner circumferential surface of the inner ring. higher than the height, the pair of inner rings of certain width in a state of butted is equal to or less than the width of the outer ring, the outer peripheral surface of the second cylindrical portion of the inner circumferential surface of the cylindrical portion of the front Kigairin inner ring contact seal is press-fitted into the opening of the annular space formed between the outer rolling double row of outer race To adopt a configuration in which a surface hardening treatment is applied to the inner rolling run side surface and the inner ring.

Thus, an outer ring having a double row rolling surface formed on the inner circumferential surface, a pair of inner rings having an inner rolling surface opposed to the outer rolling surface of the double row on the outer circumference, and the both rolling and a rolling element of double row rollably contained between the contact surface, the front Kigairin and the inner ring is formed by press working or rolling process from plate or pipe material, the outer ring includes a cylindrical portion And a concave portion that is formed at the center of the cylindrical portion and whose outer periphery is recessed toward the inner diameter side, and an annular convex portion that protrudes radially inward is formed on the inner peripheral side corresponding to the recess portion on the inner peripheral surface. Further, double-row outer rolling surfaces are formed on the inner peripheral surfaces on both sides of the annular convex portion, and further, cylindrical portions extending outward in the axial direction are formed on both sides thereof. Is thinner than the thickness of the part where the outer rolling surface is formed, and the pair of inner rings are symmetrically abutted with no gap between them A first cylindrical portion that extends in the axial direction from the abutting portion and an inner rolling surface that continues to the first cylindrical portion are formed, and the first cylinder of these inner rolling surfaces is formed. A second cylindrical portion extending in the axial direction is formed on the side different from the portion where the portion is formed, and the inner peripheral surface of these second cylindrical portions is larger in diameter than the inner peripheral surface of the first cylindrical portion. The height of the outer diameter surface of the second cylindrical portion with respect to the inner rolling surface of the ring is higher than the height of the inner peripheral surface of the annular convex portion with respect to the outer rolling surface of the outer ring, and the width of the pair of inner rings in the attached state is equal to or less than the width of the outer ring, the contact-type seal is press-fitted into the opening of the annular space formed between the outer peripheral surface of the second cylindrical portion of the inner peripheral surface and the inner ring of the cylindrical portion of the outer ring, the outer ring Since the double row outer raceway and the inner raceway inner raceway are surface hardened, the lubrication grease enclosed in the bearing Graphics and leakage, it is possible to prevent the rain water or dusts into the bearing from entering from the outside, it is possible to provide a bearing device for a high life wheel. Further, by providing cylindrical portions on the outer ring and the inner ring, a space for mounting the seal can be secured, and the seal can be suitably performed. Further, by using the side surface of the cylindrical portion to which the seal is attached as a contact surface, not only positioning but also a first cylindrical portion whose inner peripheral surface is a fitting surface is formed on the pair of inner rings. With the cylindrical portion of 1 being abutted, pressure is applied from both sides to the pair of inner rings between the shoulder portion of the hub wheel and the shoulder portion of the outer joint member to provide an appropriate bearing preload, thereby extending the life of the bearing. I can . By using the side surfaces of these cylindrical portions as contact surfaces, bearing preload can be applied and positioned, and by adjusting the length of the cylindrical portion, the outer joints of conventional hub wheels and constant velocity universal joints can be used. Since the bearing device can be assembled without changing the design of the member, the device can be made inexpensive. Furthermore, the height of the outer diameter surface of the second cylindrical portion with respect to the inner raceway surface of the inner ring is made higher than the height of the inner peripheral surface of the annular convex portion with respect to the outer raceway surface of the outer ring. Can be improved.

Further, the present invention provides a hub wheel integrally having a wheel mounting flange at one end and a cylindrical small-diameter step portion extending in an axial direction from the wheel mounting flange through a shoulder on the outer periphery, and the pair of inner rings. An inner peripheral surface of the first cylindrical portion is press-fitted into the small-diameter step portion, and a gap is formed between the second cylindrical portion inner periphery of each inner ring and the small-diameter step portion outer periphery, and the pair of inner rings Of these, the end surface of the second cylindrical surface of the inner ring on the outboard side is fixed in contact with the shoulder of the hub wheel, so that the device is lighter and the wheel is highly rigid even if a thin material is used as the material. Bearings can be obtained.

Further, the present invention includes a serration formed on the inner periphery of the hub wheel, and an outer joint member of a constant velocity universal joint fitted through the serration, the shoulder of the outer joint member and the hub wheel The bearing preload is applied by applying pressure from both sides to the pair of inner rings. Thereby, since the preload can be applied simultaneously with the assembly of the bearing device, it is not necessary to provide a preload step separately, and the cost can be reduced. Further, since an appropriate preload can be applied, stable bearing performance can be maintained, and the life of the bearing device can be extended.

In the present invention, the outer peripheral surface of the outer ring is press-fitted and fixed to the knuckle.

Wheel bearing device according to the present invention, the inner peripheral surface and outer ring double row of rolling surfaces are formed, the pair of the inner rolling run surface opposed to the outer rolling run surfaces of the double row is formed on the outer periphery an inner ring, said and a rolling elements rollably accommodated in double row between the two rolling surfaces, together with the outer ring and the inner ring is formed by press working or rolling process from plate or pipe material, the The outer ring has a cylindrical portion and a concave portion formed at the center of the cylindrical portion and having an outer periphery recessed toward the inner diameter side, and radially inward on the inner peripheral side corresponding to the concave portion on the inner peripheral surface. A projecting annular projection is formed, the outer circumferential rolling surface of the double row is formed on the inner peripheral surface of both sides of the annular projection, and a cylindrical portion extending axially outward is further formed on both sides thereof. And the cylindrical portion is thinner than the portion where the outer rolling surface is formed, and the pair of inner rings are the same. Are arranged symmetrically with no gap between them, and a first cylindrical portion extending in the axial direction and an inner rolling surface connected to the first cylindrical portion are respectively formed from the butted portion. A second cylindrical portion extending in the axial direction is formed on a different side of the inner rolling surface from the first cylindrical portion, and the inner peripheral surface of the second cylindrical portion is the first cylinder. And the height of the outer diameter surface of the second cylindrical portion with respect to the inner rolling surface of the inner ring is larger than the inner circumferential surface of the inner ring. higher than the height, the pair of inner rings of certain width in a state of butted is equal to or less than the width of the outer ring, the outer peripheral surface of the second cylindrical portion of the inner circumferential surface of the cylindrical portion of the front Kigairin inner ring contact seal is press-fitted into the opening of the annular space formed between the outer rolling double row of outer race Since the inner raceway surface of the inner ring is surface hardened, it is possible to prevent leakage of lubricating grease sealed inside the bearing and prevent rainwater and dust from entering the bearing from the outside. A wheel bearing device can be provided. Further, by providing cylindrical portions on the outer ring and the inner ring, a space for mounting the seal can be secured, and the seal can be suitably performed. Further, by using the side surface of the cylindrical portion to which the seal is attached as a contact surface, not only positioning but also a first cylindrical portion whose inner peripheral surface is a fitting surface is formed on the pair of inner rings. With the cylindrical portion of 1 being abutted, pressure is applied from both sides to the pair of inner rings between the shoulder portion of the hub wheel and the shoulder portion of the outer joint member to provide an appropriate bearing preload, thereby extending the life of the bearing. I can . By using the side surfaces of these cylindrical portions as contact surfaces, bearing preload can be applied and positioned. Furthermore, the height of the outer diameter surface of the second cylindrical portion with respect to the inner raceway surface of the inner ring is higher than the height of the inner peripheral surface of the annular convex portion with respect to the outer raceway surface of the outer ring, thereby increasing its rigidity and improving durability. By adjusting the length of the cylindrical portion, the bearing device can be assembled without changing the design of the outer joint member of the conventional hub wheel or constant velocity universal joint, so that the device can be manufactured at low cost. it can. Furthermore, by using the cylindrical portion of the outer ring and the first cylindrical portion of the inner ring as mating surfaces with the knuckle and the small-diameter step portion of the hub ring, respectively, a highly rigid wheel bearing can be obtained even if a thin material is used. The outer diameter surface of the second cylindrical portion with respect to the inner raceway surface of the inner ring can be obtained, even in the inner ring, which is smaller in diameter than the outer ring, increases the generated surface pressure, and becomes more difficult to ride on the contact ellipse. Can be made higher than the height of the inner peripheral surface of the annular convex portion with respect to the outer raceway surface of the outer ring, and the rigidity can be increased and the durability can be improved.

An outer ring in which a double row rolling surface is formed on the inner peripheral surface , a pair of inner rings in which an inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and between the two rolling surfaces A plurality of rolling elements accommodated in a freely rolling manner, and at least an outer ring of the outer ring or the inner ring is formed by cold rolling from a pipe material , and the outer ring has a cylindrical portion and An annular convex portion that protrudes radially inward is formed on the inner peripheral side of the inner peripheral surface corresponding to the concave portion formed on the inner peripheral surface. The outer circumferential rolling surface of the double row is formed on the inner peripheral surface on both sides of the annular convex portion, and the cylindrical portion extending outward in the axial direction is formed on both sides of the outer circumferential rolling surface. The thickness is thinner than the thickness of the portion where the outer rolling surface is formed, and the pair of inner rings are symmetrically shaped with the same shape. A first cylindrical portion that extends in the axial direction from the abutting portion, and an inner rolling surface that continues to the first cylindrical portion is formed. A second cylindrical portion extending in the axial direction is formed on a different side from the one cylindrical portion formed, and the inner peripheral surface of these second cylindrical portions is larger in diameter than the inner peripheral surface of the first cylindrical portion. The height of the outer diameter surface of the second cylindrical portion with respect to the inner rolling surface of the inner ring is higher than the height of the inner peripheral surface of the annular convex portion with respect to the outer rolling surface of the outer ring. the pair of width of the inner ring is equal to or less than the width of the outer ring, the opening of the annular space formed by the inner peripheral surface of the cylindrical portion of the front Kigairin and the second outer peripheral surface of the cylindrical portion of the inner ring in contact seal is press-fitted into parts, baked on the inner rolling run surface of the outer raceway surface inner ring of the double row of outer race Cured layer is formed by Les.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a wheel bearing device according to the present invention, and FIG. 2 is an enlarged view of a main part of FIG. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side of the drawing in FIG. 1), and the side closer to the center is referred to as the inner side (right side of the drawing in FIG. 1).

  In the wheel bearing device according to the present invention, the hub wheel 1, the double row rolling bearing 2 and the constant velocity universal joint 3 are detachably unitized.

  As shown in FIG. 2, the double-row rolling bearing 2 is opposed to the outer ring 4 in which double-row outer rolling surfaces 4a and 4a are formed on the inner circumference, and the double-row outer rolling surface on the outer circumference. It is composed of a pair of inner rings 5 and 5 in which double row inner rolling surfaces 5a and 5a are formed, and double row rolling elements (balls) 6 and 6 accommodated so as to be freely rollable between both rolling surfaces. ing. The outer ring 4 and the inner ring 5 are made of a stainless steel flat plate or pipe material having a rust prevention ability, and are formed by pressing or rolling.

  The outer peripheral surface of the outer ring 4 has a substantially cylindrical shape and is press-fitted and fixed to the knuckle 7. A protrusion 7 a is formed on the inner side of the knuckle 7 in the radial direction. The protrusion 7 a abuts against the side surface of the outer ring 4 so that the outer ring 4 is aligned. The cross-sectional height of the protrusion 7 a is substantially equal to the height of the side surface of the outer ring 4.

  An annular convex portion 4b that protrudes radially inward is formed by pressing or rolling at a substantially central portion of the inner peripheral surface of the outer ring 4. Double row outer rolling surfaces 4a, 4a having a substantially arc-shaped cross section are formed on the inner peripheral surfaces on both sides of the annular convex portion 4b. Cylindrical portions 4c and 4c extending in the axial direction are formed on both sides of the outer rolling surfaces 4a and 4a. The thickness of the cylindrical portions 4c and 4c is thinner than the thickness of the outer rolling surfaces 4a and 4a. At least both outer rolling surfaces 4a and 4a of the outer ring 4 are subjected to surface hardening treatment such as carburizing and quenching.

  The inner rings 5 and 5 are arranged so that the same shape is abutted symmetrically. There is no gap in the butting portion 5b. The inner rings 5 and 5 are formed with first cylindrical portions 5c and 5c extending in the axial direction from the butted portion 5b. Inner rolling surfaces 5a and 5a having a substantially arc-shaped cross section are formed on the outer peripheral surfaces on the sides of the first cylindrical portions 5c and 5c, respectively. Second cylindrical portions 5d and 5d extending in the axial direction are formed on both sides of the inner rolling surfaces 5a and 5a. At least both inner rolling surfaces 5a and 5a of the inner rings 5 and 5 are subjected to surface hardening treatment such as carburizing and quenching.

  Between the outer rolling surfaces 4a, 4a and the inner rolling surfaces 5a, 5a, double-row rolling elements 6, 6 are accommodated, respectively. The rolling elements 6 and 6 are held by the cages 8 and 8 so as to freely roll. In this example, a ball is used as the rolling element 6. However, a double row tapered roller bearing using a tapered roller as the rolling element 6 may be used.

  Seals 13 and 13 are attached to the openings of the annular space formed between the cylindrical portions 4 c and 4 c of the outer ring 4 and the second cylindrical portions 5 d and 5 d of the inner rings 5 and 5. The seals 13 and 13 include core bars 11 and 11 having a substantially U-shaped cross section, and seal members 12 and 12 joined to the core bars 11 and 11. The metal cores 11 and 11 are formed by press working from a plate material or a pipe material having rust prevention ability. The outer peripheral surfaces of the core bars 11 and 11 are press-fitted and fixed to the inner peripheral surfaces of the cylindrical portions 4 c and 4 c of the outer ring 4. The seal members 12 and 12 include joint portions 12a and 12a that are joined to the cores 11 and 11, two seal lips 12b and 12b, and seal lips 12c and 12c. The end portions of the seal lips 12b, 12b and the seal lips 12c, 12c are in sliding contact with the outer peripheral surfaces of the second cylindrical portions 5d, 5d of the inner rings 5, 5. Since the seal lips 12b and 12b and the seal lips 12c and 12c are elastic, and the core bars 11 and 11 are formed in a cross-sectional shape, the seals 13 and 13 are formed of the cylindrical portion 4c of the outer ring 4, 4c and the second cylindrical portions 5d and 5d of the inner rings 5 and 5 are mounted in a state of suitable elastic deformation, so that leakage of the lubricating grease sealed inside the bearing and the inside of the bearing from the outside It is possible to suitably prevent rainwater and dust from entering.

  On the inner side of the hub wheel 1, a small-diameter step portion 1a having a cylindrical shape extending in the axial direction is formed. Inner rings 5 and 5 are fitted to the outer peripheral surface of the small diameter step portion 1a. The outer peripheral surface of the small diameter step portion 1a and the first cylindrical portions 5c and 5c of the inner rings 5 and 5 are fitted with no gap.

  A wheel mounting flange 1 b for mounting a wheel (not shown) is formed at the outer end of the hub wheel 1. Hub bolt insertion holes 1c are equally formed in the circumferential direction of the wheel mounting flange 1b. A hub bolt (not shown) for fixing the wheel is planted in the hub bolt insertion hole 1c. On the inner periphery of the hub wheel 1, a serration (or spline) 1d for torque transmission is formed. The shoulder 1e of the hub wheel 1 is in contact with the side surface of the inner ring 5 on the outer side. The hub wheel 1 is made of medium carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least the outer peripheral surface of the small-diameter stepped portion 1a is hardened by induction hardening to a surface hardness of 58 to 64 HRC. Has been.

  The constant velocity universal joint 3 includes an outer joint member 14, a joint inner ring 15, a cage 16 and a torque transmission ball 17. The outer joint member 14 includes a cup-shaped mouth portion 18, a shoulder portion 19 that forms the bottom of the mouth portion 18, a hollow shaft portion 20 that extends in the axial direction from the shoulder portion 19, and an axially extending member. And a threaded portion 21. Curved track grooves 18 a and 15 a extending in the axial direction are formed on the inner periphery of the mouse portion 18 and the outer periphery of the joint inner ring 15, respectively. A torque transmission serration (or spline) 20 a is formed on the outer periphery of the shaft portion 20 of the outer joint member 14. The shoulder 19 of the outer joint member 14 is in contact with the side surface of the inner ring 5 on the inner side. The outer joint member 14 is made of medium carbon steel containing carbon 0.40 to 0.80 wt% such as S53C, and the outer circumferential surface extending from the shoulder portion 19 to the shaft portion 20 including the track grooves 18a and 15a is induction-hardened. The surface hardness is set in the range of 58 to 64 HRC.

  The shaft portion 20 of the outer joint member 14 is fitted to the inner periphery of the hub wheel 1. Torque is transmitted when the serration 20 a of the shaft portion 20 of the outer joint member 14 meshes with the serration 1 d of the hub wheel 1. The outer joint member 14 fitted in the hub wheel 1 is fixed with a constant torque by screwing a spindle nut 22 into the male thread portion 21 thereof. At this time, the shoulder 1e of the hub wheel 1 is in contact with the side surface of the inner ring 5 on the outer side, and the shoulder 19 of the outer joint member 14 is in contact with the side surface of the inner ring 5 on the inner side. When the inner rings 5 and 5 are raised, pressure is applied from both sides, and a preload is applied to the bearing 2.

Next, a method for manufacturing the outer ring 4 and the inner ring 5 will be described.
3A and 3B are diagrams showing a method of manufacturing the outer ring 4, in which FIG. 3A shows a state before processing, and FIG. 3B shows a state during processing. 4A and 4B are diagrams showing a method for manufacturing the inner ring 5, in which FIG. 4A shows a state before processing, and FIG. 4B shows a state during processing.

  In the center of FIG. 3 (a), a cross section of a pipe member 31 made of stainless steel having a rust-proofing ability as a base material of the outer ring 4 is shown. The pipe material 31 is formed by cutting a long pipe material to a desired length, deburring both ends of the cut pipe material, and turning the inner diameter surface and the outer diameter surface. A mandrel 32 extending in the axial direction is inserted into the pipe material 31 with a clearance from the inner peripheral surface of the pipe material 31. On the outer peripheral surface of the mandrel 32, molds such as convex portions 32a and 32b for forming the outer rolling surfaces 4a and 4a of the outer ring 4 are formed. A molding roll 33 that contacts the outer peripheral surface of the pipe material 31 is disposed outside the pipe material 31. On the outer peripheral surface of the molding roll 33, a mold such as a convex portion 33a for forming an annular convex portion 4b protruding inward in the radial direction of the outer ring 4 is formed.

  As shown in FIG. 3B, when processing, the pipe material 31 is sandwiched between the molding roll 33 and the mandrel 32. Then, by rotating at least one of the forming roll 33 and the mandrel 32, a desired shape can be formed over the peripheral surface of the pipe 31. Finally, unnecessary portions at the ends of the processed pipe material 31 are removed by machining. The outer ring 4 is formed by such a cold rolling process.

  In the center of FIG. 4 (a), a cross section of a pipe member 41 made of stainless steel having a rust-proofing ability as a base material for the inner ring 5 is shown. The pipe material 41 is formed by cutting a long pipe material to a desired length, deburring both ends of the cut pipe material, and turning the inner diameter surface and the outer diameter surface. An inner die 42 extending in the axial direction is inserted into the pipe material 41 with a clearance from the inner peripheral surface of the pipe material 41. A die for forming the inner peripheral surface of the inner ring 5 is formed on the outer peripheral surface of the inner die 42. An outer mold 43 that is brought into contact with the outer peripheral surface of the pipe material 41 is disposed outside the pipe material 41. The outer mold 43 is formed with a mold such as a convex portion 43 a for forming the inner rolling surface 5 a of the inner ring 5.

  As shown in FIG. 4B, when processing, a desired shape can be formed over the peripheral surface of the pipe 41 by sandwiching and pressing the pipe material 41 between the inner mold 42 and the outer mold 43. it can. Finally, unnecessary portions at the ends of the processed pipe material 41 are removed by machining. The inner ring 5 is formed by such pressing.

  In this embodiment, an example is shown in which the outer ring 4 and the inner ring 5 are processed using a pipe material as a base material, but the present invention can be formed by a similar processing method using the outer ring 4 and the inner ring 5 as flat plates. . In this embodiment, the outer ring 4 is formed by rolling and the inner ring 5 is press-molded. However, in the present invention, the outer ring 4 can be press-molded and the inner ring 5 can be formed by rolling. . Furthermore, it is sufficient that at least one of the outer ring 4 or the inner ring 5 is formed from a plate material or a pipe material by pressing or rolling, and the other can be processed by forging or the like.

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

The wheel bearing device according to the present invention can be applied to a so-called first- generation wheel bearing device that rotatably supports a wheel of an automobile or the like.

It is a longitudinal section showing an embodiment of a wheel bearing device concerning the present invention. It is a principal part enlarged view of FIG. It is a figure which shows the manufacturing method of the outer ring | wheel 4, (a) shows the state before a process, (b) shows the state in process. It is a figure which shows the manufacturing method of the inner ring | wheel 5, (a) shows the state before a process, (b) shows the state in process.

Explanation of symbols

1 ... hub wheel 1a ... small diameter step 1b ... wheel mounting flange 1c ... hub bolt insertion hole 1d ... ··· Serration 1e ·········································································· • 4a ... Outer rolling surface 4b ... Annular projection 4c ... Cylindrical part 5 ... Inner ring 5a ... -Inner rolling surface 5b .... Butting part 5c ... ... First cylindrical part 5d ... ... Second cylindrical part 6 ... Rolling element 7 ... Knuckle 7a ... Projection 8 ... Retainer 11 ... Core 12 ... · Sealing member 12a ··· Joints 12b, 12c ··· Seal ·································································································· Tracks 16・ ・ ・ ・ ・ ・ Torque transmission ball 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mouse part 19 ・ ・ ・ ・ ・ ・ Shoulder part 20 ・ ・ ・ ・ ・ ・ Shaft part 20 a ・ ・ ・ ・ ・ ・ Serration 21 ・ ・... Screw thread 22 ... Spindle nuts 31, 41 ... Pipe material 32 ... Mandrels 32a, 32b ... Projections 33 ...・ Molding roll 33a ・ ・ ・ ・ ・ ・ Convex part 42 ・ ・ ・ ・ ・ ・ Inner mold 43 ・ ・ ・ ・ ・ ・ External mold 43a ・ ・ ・ ・ ・ ・ Convex part

Claims (4)

An outer ring in which a double row rolling surface is formed on the inner peripheral surface , a pair of inner rings in which an inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and between the two rolling surfaces A double row rolling element accommodated in a freely rolling manner,
The outer ring and the inner ring are formed by pressing or rolling from a plate material or pipe material,
The outer ring has a cylindrical portion and a recessed portion formed at the center of the cylindrical portion and having an outer periphery recessed toward the inner diameter side, and a radially inner side on the inner peripheral side corresponding to the recessed portion on the inner peripheral surface. An annular projecting portion is formed on the inner circumferential surface on both sides of the annular projecting portion, and the outer circumferential rolling surface of the double row is formed on both sides of the annular projecting portion. Is formed, the thickness of the cylindrical portion is thinner than the thickness of the portion where the outer rolling surface is formed,
The pair of inner rings, which have the same shape, are arranged in a butt-symmetrical manner with no gap therebetween, a first cylindrical portion extending in the axial direction from the butt portion, and an inner side continuous with the first cylindrical portion. Each of the rolling surfaces is formed, and a second cylindrical portion extending in the axial direction is formed on a different side of the inner rolling surface from which the first cylindrical portion is formed. The circumferential surface is larger in diameter than the inner circumferential surface of the first cylindrical portion, and the height of the outer diameter surface of the second cylindrical portion with respect to the inner rolling surface of the inner ring is the annular shape with respect to the outer rolling surface of the outer ring. The width of the pair of inner rings that are higher than the height of the inner peripheral surface of the convex part and are in an attached state is equal to or less than the width of the outer ring,
Contact seal is press-fitted into the opening of the annular space formed between the outer peripheral surface of the second cylindrical portion of the inner circumferential surface of the cylindrical portion of the front Kigairin inner ring, an outer rolling double row of outer race A wheel bearing device, wherein the surface and the inner raceway surface of the inner ring are subjected to surface hardening treatment. A hub wheel having a wheel mounting flange integrally at one end and a cylindrical small-diameter stepped portion extending axially from the wheel mounting flange through a shoulder on the outer periphery, and a first cylindrical portion of the pair of inner rings The inner peripheral surface of the inner ring is press-fitted into the small-diameter step portion, and a gap is formed between the inner periphery of the second cylindrical portion of each inner ring and the outer periphery of the small-diameter step portion. The wheel bearing device according to claim 1, wherein an end surface of the second cylindrical surface of the inner ring is fixed in contact with a shoulder portion of the hub wheel . A serration is formed on the inner periphery of the hub wheel, and an outer joint member of a constant velocity universal joint fitted through the serration is provided, and a shoulder portion of the outer joint member and a shoulder portion of the hub wheel, The wheel bearing device according to claim 2, wherein a bearing preload is applied to the pair of inner rings by applying pressure from both sides. The wheel bearing device according to any one of claims 1 to 3, wherein an outer peripheral surface of the outer ring is press-fitted and fixed to a knuckle .

Images