JP2008303923A - Wheel bearing and wheel bearing device equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel bearing reduced in weight, size, and cost, and having improved sealing performance, and to provide a wheel bearing device equipped therewith. <P>SOLUTION: The wheel bearing forms a back-to-back type double-row angular ball bearing. An outward member 7 and an inner ring 8 are each formed from a pipe material with cold rolling work. The inner ring 8 has a shoulder portion 13 extending from the large diameter side of an inside rolling surface 8a in the axial direction, and a side plate portion 14 extending from the shoulder portion 13 outward in the radial direction. A seal 26 consists of a core metal 28 fitted to a cylindrical portion 12b of the outward member 7, and a seal member 29 integrally joined to the core metal 28 and having a side lip 29a and a pair of radial lips 29b, 29c put in slide contact with the shoulder portion 13 of the inner ring 8. The side lip 29a is put in slide contact with the side plate portion 14, and the outer edge of the side plate portion 14 and the core metal 28 face each other via a slight radial clearance to form a labyrinth seal 30. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a wheel bearing for rotatably supporting a wheel of a vehicle such as an automobile, and more specifically, to provide a wheel bearing and a wheel bearing that achieves a light weight, a compact size and a low cost and an improved sealing performance. The present invention relates to a wheel bearing device.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like supports a hub wheel for mounting a wheel rotatably via a double row rolling bearing, and includes a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and both an inner ring rotation method and an outer member rotation method are generally used for driven wheels. This wheel bearing device has a structure called a first generation in which a wheel bearing composed of a double-row angular ball bearing or the like is fitted between a knuckle and a hub wheel constituting a suspension device, and is an outer member. 2nd generation structure with body mounting flange or wheel mounting flange formed directly on the outer periphery of the wheel, 3rd generation structure with one inner rolling surface formed directly on the outer periphery of the hub wheel, or constant speed with the hub wheel It is roughly classified into a fourth generation structure in which the inner rolling surface is directly formed on the outer periphery of the outer joint member of the universal joint.

  Conventionally, an angular ball bearing having a structure in which an inner ring and an outer ring are formed from a steel plate by pressing is known. For example, the angular ball bearing 50 shown in FIG. 8 is used in a magnetic hard disk device or the like, but the outer ring (outer member) 51 and the pair of inner rings 52 and 53 are made of stainless steel by pressing or rolling. Is formed.

  The outer ring 51 is formed with an annular convex portion 51a protruding radially inward at a substantially middle portion of the inner peripheral surface, and outer rolling surfaces 51b and 51c are formed on inner peripheral surfaces on both sides of the annular convex portion 51a. Yes. The outer ring 51 has an outer peripheral surface fitted into a hole in the housing 54, and a flange 51 d formed at one end is brought into contact with the end surface of the housing 54 to perform axial positioning. An annular recess 51e is formed on the outer peripheral surface of the outer ring 51 by the annular protrusion 51a. The annular recess 51e is filled with an adhesive, and the outer ring 51 is fixed to the hole of the housing 54.

  On the other hand, the inner rings 52 and 53 are respectively fitted inside the double row outer raceway surfaces 51b and 51c of the outer ring 51 from both sides in the axial direction. Curved shoulder portions 52a and 53a are formed on the outer circumferences of the outer ends in the axial direction of the inner rings 52 and 53, and inner rolling surfaces 52b and 53b are formed on the curved shoulder portions 52a and 53a. The double rows of balls 56, 56 are arranged between the inner rolling surfaces 52b, 53b and the outer rolling surfaces 51b, 51c of the outer ring 51, and are retained by the cages 57, 57 for each row. Is retained.

  On the inner peripheral surfaces of the inner rings 52 and 53, fitting portions 52c and 53c that are fitted into the shaft member 55 with clearance are formed. After the inner rings 52, 53 are fitted into the shaft member 55 in the axial direction, a cylindrical weight 59 having a constant weight is placed on the curved shoulder 52 a of one inner ring 52, and the weight of the weight 59 The other inner ring 53 is pressed via the inner ring 52, the ball 56, the outer ring 51, and the ball 56, and the curved shoulder portion 53 a is fitted until it comes into contact with the flange portion 55 a of the shaft member 55. Thereby, an appropriate preload is set for the angular ball bearing 50.

When this gap fitting is completed, the adhesive 60 is filled in the gap between the curved shoulder portion 52a of the one inner ring 52 and the shaft member 55, and this adhesive 60 prevents the one inner ring 52 from being fitted off. The flange portion 55a of the shaft member 55 prevents the other inner ring 53 from being fitted off.
Japanese Utility Model Publication No. 6-1835

  However, when this type of angular contact ball bearing made of press is used as a wheel bearing, a sealing device (not shown) is installed between the outer ring 51 and the inner rings 52 and 53, for example, in order to ensure sealing performance. However, it is necessary to change the structure in order to secure a seal structure with high sealing performance and a seal space while achieving compactness.

  The present invention has been made in view of the above circumstances, and provides a wheel bearing and a wheel bearing device including the same, which are light and compact and cost-effective and have improved sealing performance. The purpose is that.

  In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member in which a double-row arc-shaped outer rolling surface is integrally formed on the inner periphery, and the double-row on the outer periphery. A pair of inner rings formed with an arcuate inner rolling surface facing the outer rolling surface, a double row of balls accommodated between the inner ring and both rolling surfaces of the outer member, and the outer member And a seal attached to an opening of an annular space formed between the inner ring and the inner ring, and a pair of inner ring small-diameter side end surfaces abutted in a butted state to form a back-to-back type double row angular ball bearing In the wheel bearing to be configured, the outer member and the inner ring are formed by plastic processing from a pipe material, and a shoulder portion extending in the axial direction from the large diameter side of the inner rolling surface of the inner ring, and the shoulder portion Side plate portion extending radially outward from the side plate portion, and the side plate portion and the seal slightly Labyrinth seals are formed to face through the or.

  As described above, in the wheel bearing constituted by the back-to-back type double row angular contact ball bearing, the outer member and the inner ring are formed by plastic working from the pipe material, and the inner ring has a large inner rolling surface. A shoulder portion extending in the axial direction from the radial side and a side plate portion extending radially outward from the shoulder portion are formed, and the labyrinth seal is formed by facing the side plate portion and the seal through a slight gap. Therefore, it is possible to prevent the leakage of grease sealed inside the bearing, and to prevent foreign matter such as rainwater and dust from entering the seal sliding contact part from the outside, providing a wheel bearing with improved sealing performance. can do.

  Preferably, if the outer member and the inner ring are formed by cold rolling as in the second aspect of the invention, productivity is improved, yield is improved, and cost can be reduced.

  According to a third aspect of the present invention, the seal is joined to the cylindrical part of the outer member, and the core is integrally joined to the shoulder of the inner ring. And a seal member having a pair of radial lips, and the labyrinth seal may be formed by facing the seal member and the side plate portion through a slight axial clearance.

  According to a fourth aspect of the present invention, the seal is joined to the cylindrical portion of the outer member, and the core is integrally joined to the shoulder of the inner ring. A pair of radial lips and a seal member having a side lip extending in a radially outward direction, the side lip being slidably contacted with the side plate portion, and an outer edge of the side plate portion and the core metal However, the labyrinth seal may be formed through a slight radial clearance.

  In addition, as in the invention described in claim 5, if the both rolling surfaces and the shoulder portion of the inner ring are formed with a predetermined size and accuracy by grinding, the same accuracy and sealing performance as a conventional bearing are provided. Can be secured.

  Further, as in the invention described in claim 6, if the thickness of the side plate portion is set to be thinner than the thickness of the inner rolling surface, the axial direction can be made compact and the processing accuracy can be improved. Can be made.

  Further, the invention according to claim 7 of the present invention has a wheel mounting flange for mounting a wheel at one end portion, and a small-diameter step portion extending in an axial direction from the wheel mounting flange via a shoulder portion. A wheel hub according to any one of claims 1 to 6, comprising a formed hub wheel and a wheel bearing according to any one of claims 1 to 6 press-fitted into a small-diameter step portion of the hub wheel through a predetermined shimiro, and a constant velocity universal joint is provided on the hub wheel. The outer joint member is internally fitted via a serration, a fixing nut is attached to the male screw formed at the end of the serration, and the pair of inner rings are connected to the shoulder portion of the hub wheel and the shoulder of the outer joint member. A predetermined bearing preload is applied by tightening the fixing nut with a predetermined tightening torque in a state of being sandwiched between the portions.

  Thus, in the wheel bearing device of the first generation structure, a hub wheel having a wheel mounting flange integrally formed at one end and a small-diameter step portion extending in the axial direction from the wheel mounting flange via the shoulder is formed. And a wheel bearing according to any one of claims 1 to 4, which is press-fitted into the small-diameter step portion of the hub ring via a predetermined shimiro, and an outer joint member of a constant velocity universal joint is provided on the hub ring. Since the inner ring is fitted through the serration and the pair of inner rings are sandwiched between the shoulder part of the hub wheel and the shoulder part of the outer joint member and given a predetermined bearing preload, the bearing rigidity is increased, The rolling fatigue life of the bearing is improved.

  The wheel bearing according to the present invention includes an outer member in which a double-row arc-shaped outer rolling surface is integrally formed on the inner periphery, and an arc-shaped inner surface facing the outer-rolling surface of the double-row on the outer periphery. An annular space formed between a pair of inner rings formed with rolling surfaces, a double row of balls accommodated between both inner rings and the rolling surfaces of the outer member, and the outer member and the inner ring. A pair of inner ring small-diameter side end surfaces abutting in a butted state to form a back-to-back type double row angular contact ball bearing, wherein the outer member And the inner ring are formed from pipe material by plastic working, and the inner ring is formed with a shoulder portion extending in the axial direction from the large-diameter side of the inner rolling surface and a side plate portion extending radially outward from the shoulder portion. The side plate and the seal face each other through a slight gap so that the labyrinth As a result, the grease sealed inside the bearing is prevented from leaking, and foreign matter such as rainwater and dust is prevented from entering the seal sliding contact portion from the outside to improve the sealing performance. A wheel bearing can be provided.

  A pair of outer members in which a double-row arc-shaped outer rolling surface is integrally formed on the inner periphery, and an arc-shaped inner rolling surface facing the outer-rolling surface of the double-row is formed on the outer periphery. An inner ring, a double row of balls accommodated between the rolling surfaces of the inner ring and the outer member, and a seal attached to an opening of an annular space formed between the outer member and the inner ring. A small-diameter side end face of the pair of inner rings abuts in a butted state to form a back-to-back type double row angular contact ball bearing, wherein the outer member and the inner ring are cold from the pipe material. The inner ring is formed by a rolling process, a shoulder portion extending in the axial direction from the large diameter side of the inner rolling surface thereof, and a side plate portion extending radially outward from the shoulder portion are formed, and the seal is A cored bar fitted into the cylindrical portion of the outer member, and integrally joined to the cored bar, A pair of radial lips slidably in contact with the shoulder portion of the inner ring and a seal member having a side lip extending obliquely outward in the radial direction, and the side lip is slidably in contact with the side plate portion. A labyrinth seal is formed by the outer edge and the core metal facing each other through a slight radial clearance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a longitudinal sectional view showing a wheel bearing device to which a wheel bearing according to the present invention is applied, FIG. 2 is an enlarged view showing the wheel bearing of FIG. 1, and FIG. 3 shows the seal of FIG. FIG. 4A is a longitudinal sectional view showing a single outer member in FIG. 2, FIG. 4B is a longitudinal sectional view showing a single inner ring in FIG. 2, and FIG. 5 is an enlarged main portion in FIG. FIG. In the following description, the side closer to the outer side of the vehicle in a state assembled to the vehicle is referred to as the outer side (left side in the drawing), and the side closer to the center is referred to as the inner side (right side in the drawing).

  This wheel bearing device has a first generation structure on the drive wheel side, and includes a hub wheel 1 and a wheel bearing 2 attached to the hub wheel 1. A constant velocity universal joint 3 is fitted into the hub wheel 1 so as to be able to transmit torque, and the hub wheel 1 and the constant velocity universal joint 3 are connected to each other via a fixing nut 4 so as to be separable in the axial direction.

  The hub wheel 1 has a wheel attachment flange 5 for attaching a wheel (not shown) to an end portion on the outer side, and a cylindrical shape extending from the wheel attachment flange 5 to the outer periphery in the axial direction via a shoulder portion 1a. A small-diameter step portion 1b is formed, and a serration (or spline) 1c for torque transmission is formed on the inner periphery. The hub wheel 1 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the surface hardness after forging remains unchanged. Also, tempering is performed after forging to increase fatigue strength against bending strength, or surface hardness is set to a range of 58 to 64 HRC by induction quenching from shoulder 1a to small diameter step 1b. May be.

  The constant velocity universal joint 3 includes an outer joint member 15, a joint inner ring 16, a cage 17, and a torque transmission ball 18. The outer joint member 15 is made of medium-high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and has a cup-shaped mouth portion 19, a shoulder portion 20 which is the bottom portion of the mouth portion 19, and the shoulder portion. A shaft portion 21 extending in the axial direction from 20 is integrally provided. A serration 21a that engages with the serration 1c of the hub wheel 1 is formed on the outer periphery of the shaft portion 21, and a male screw 21b is formed at the end of the serration 21a.

  The wheel bearing 2 is fitted into a knuckle 6, and as shown in an enlarged view in FIG. 2, an outer member 7 having double rows of arc-shaped outer rolling surfaces 7a, 7a formed on the inner periphery, and an outer periphery on the outer member 7. A pair of inner races 8 and 8 formed with arcuate inner raceway surfaces 8a and 8a facing these double row outer raceway surfaces 7a and 7a, and cages 9 and 9 between both raceway surfaces. Double-row balls 10 and 10 accommodated so as to roll freely, and seals 11 and 11 attached to both ends of the outer member 7 are provided. The small-diameter (front) side end faces 8b, 8b of the inner rings 8, 8 abut each other in a butted state to constitute a so-called back-to-back type double row angular ball bearing.

  As shown in FIG. 1, the wheel bearing 2 includes the hub wheel 1 and the shaft portion 21 of the outer joint member 15 that has serrations 1 c and 21 a until the shoulder portion 20 of the outer joint member 15 abuts the end surface of the inner ring 8. And the pair of inner rings 8 and 8 are sandwiched between the shoulder portion 1a of the hub wheel 1 and the shoulder portion 20 of the outer joint member 15 via a predetermined squeeze to the small diameter step portion 1b of the hub wheel 1. It is press-fitted. A predetermined bearing preload is applied to the male screw 21b by tightening the fixing nut 4 with a predetermined tightening torque. By applying this preload, the bearing rigidity is increased and the rolling fatigue life of the bearing is improved.

  Here, the outer member 7 and the inner ring 8 are formed by plastic working such as cold rolling or pressing after annealing pipe steel made of bearing steel such as SUJ2 or carburized steel such as SCr420 or SCM415. Yes. In the case of bearing steel, the surface hardness is set to a range of 50 to 64 HRC by sublimation or induction hardening, and in the case of carburized steel, the surface hardness is in the range of 50 to 64 HRC. Other examples of the material of the outer member 7 and the inner ring 8 include SCM440, cold rolled steel plate (JIS standard SPCC system, etc.), and carbon steel such as S50C to S55C. In the case of cold rolled steel or carbon steel, at least the outer member 7 has double row outer rolling surfaces 7a, 7a, and the inner race 8 has an inner rolling surface 8a having a surface hardness of 50 to 64 HRC by induction hardening. The range is hardened to improve rolling fatigue life. These rolling surfaces 7a and 8a are formed with predetermined dimensions and accuracy by grinding. After that, superfinishing is performed as necessary.

Next, the configuration of the outer member 7 and the inner ring 8 will be described in detail with reference to FIG.
As shown in (a), the outer member 7 includes an annular protrusion 12 projecting radially inward from the pipe material, which is a raw material, by a cold rolling process, and the annular protrusion 12. Double-row arcuate outer rolling surfaces 7a and 7a are formed on both sides, and cylindrical portions 7b and 7b serving as fitting portions for the seal 11 are formed on both ends. Here, the cylindrical portion 7b is formed with a predetermined size and accuracy by grinding after rolling. Note that both end faces where burrs are likely to occur during rolling are turned after machining. Moreover, a grinding process is given as needed.

  On the other hand, as shown in (b), the inner ring 8 includes an arc-shaped inner rolling surface 8a and a shoulder extending in the axial direction from the large diameter side of the inner rolling surface 8a by rolling from a pipe material as a material. A portion 13 and a side plate portion 14 extending radially outward from the shoulder portion 13 are formed. Since the side plate portion 14 bent from the shoulder portion 13 is not subjected to a load, as shown in FIG. 5, the thickness T2 thereof is thinner than the thickness T1 of the inner rolling surface 8a (T2 ≦ T1). Preferably, T2≈T1 / 2 is set. As a result, the axial direction can be reduced, and the processing accuracy can be improved. Here, since the shoulder portion 13 becomes a seal land portion of the seal 11, it is formed with a predetermined size and accuracy by grinding after the rolling. Note that the large-diameter (rear) side end surface 8c and the small-diameter side end surface 8b, which are likely to generate burrs in rolling, are turned after machining. Moreover, a grinding process is given as needed.

  Further, in the present embodiment, the outer member 7 and the inner ring 8 are formed by cold rolling from the pipe material, so that the productivity is improved and the yield is good, and the cost can be reduced. Since the cylindrical portion 7b of the outer member 7 that becomes the fitting surface between the rolling surfaces 7a and 8a and the seal 11 and the shoulder portion 13 of the inner ring 8 that becomes the land portion of the seal 11 are formed by grinding, It is possible to ensure the same accuracy and sealing performance as those of the bearings. Here, the outer member 7 and the inner ring 8 are formed by cold rolling. However, the outer member 7 and the inner ring 8 may be formed by warm rolling, and the fitting of the knuckle 6 or the hub wheel 1 may be performed. The outer diameter surface of the outer member 7 and the inner diameter surface of the inner ring 8 serving as the mating surfaces may be formed by grinding.

  In this embodiment, as shown in an enlarged view in FIG. 3, the seal 11 is integrally joined to the cored bar 22 fitted to the cylindrical portion 7 b of the outer member 7 by vulcanization bonding or the like. The seal member 23 is made of an elastic member such as nitrile rubber and includes a pair of radial lips 23a and 23b. These radial lips 23 a and 23 b are in sliding contact with the shoulder 13 of the inner ring 8. Further, the seal member 23 and the side plate portion 14 are opposed to each other through a slight axial clearance, and a labyrinth seal 24 is formed. With this configuration, the grease sealed in the bearing is prevented from leaking, and foreign matter such as rainwater and dust is prevented from directly entering the radial lips 23a and 23b from the outside, thereby improving the sealing performance. A bearing device can be provided.

  6 is a longitudinal sectional view showing a second embodiment of the wheel bearing according to the present invention, and FIG. 7 is an enlarged view of a main part showing the seal of FIG. This embodiment basically differs from the above-described embodiment (FIG. 2) only in the configuration of the seal, and the same parts and parts having the same functions or the same functions as those of the above-described embodiments are denoted by the same reference numerals. Detailed description is omitted.

  The wheel bearing 25 includes an outer member 7, a pair of inner rings 8, 8, and double-row balls 10, 10 accommodated between the rolling surfaces via a cage 9, 9, A seal 26 attached to an opening of an annular space formed between the outer member 7 and the inner ring 8 is provided.

  As shown in an enlarged view in FIG. 7, the seal 26 is a so-called pack comprising an annular seal plate 27 mounted on the outer member 7 and a side plate portion 14 facing the seal plate 27 and having a slinger function. It consists of a seal.

  The seal plate 27 is formed in a substantially L-shaped cross section, and includes a core metal 28 press-fitted into the cylindrical portion 7b of the outer member 7, and a seal member 29 integrally joined to the core metal 28 by vulcanization adhesion or the like. Become. The core 28 is formed by press working from an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a rust-proof cold rolled steel plate (JIS standard SPCC type or the like).

  On the other hand, the seal member 29 is made of an elastic member such as nitrile rubber, and extends in a radially outward direction. Radial lips 29b, 29c. Then, the labyrinth seal 30 is configured by causing the outer edge of the side plate portion 14 and the cored bar 28 to face each other through a slight radial clearance, and prevents rainwater, dust, and the like from directly falling on the side lip 29a from the outside. Improves sex.

  Also in this embodiment, the productivity is improved, the yield is good, the cost can be reduced, and the shoulder 13 of the inner ring 8 which is the sliding contact surface between the rolling surfaces 7a, 8a and the seal 26 is ground by grinding. Since it is formed, it is possible to ensure the same accuracy as a conventional bearing and to obtain a stronger sealing performance. If necessary, the side plate portion 14 may also be ground with a total-type grindstone simultaneously with the shoulder portion 13.

  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 according to the present invention can be applied to a wheel bearing device having a first generation structure that is press-fitted into a hub wheel integrally having a wheel mounting flange at one end.

It is a longitudinal cross-sectional view which shows the wheel bearing apparatus to which the wheel bearing which concerns on this invention was applied. It is an enlarged view which shows the wheel bearing of FIG. It is a principal part enlarged view which shows the seal | sticker of FIG. (A) is a longitudinal cross-sectional view which shows the outer member ring single-piece | unit of FIG. (B) is the longitudinal cross-sectional view which shows an inner ring single-piece | unit as above. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing which concerns on this invention. It is a principal part enlarged view which shows the seal | sticker of FIG. It is a longitudinal cross-sectional view which shows the angular ball bearing in which the conventional inner / outer ring was formed by press work.

Explanation of symbols

1 ···················· Hub wheel 1a, 13, 20 ··········· Shoulder 1b ············・ Small diameter step 1c, 21a ・ ・ ・ ・ ・ ・ Serrations 2, 25 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel bearings 3 ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ Constant velocity universal joint 4 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fixing nut 5 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 6 ・... knuckle 7 ... outer member 7a ... ..Outer rolling surface 7b ... Cylindrical part 8 ... Inner ring 8a ...・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surface 8b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Small diameter side end surface 8c ・ ・ ・ ・ ・ ・ ・ ・ ・...... Large-diameter side end face 9 ............ Retainer 10 ............ Balls 11, 26 .. ···············································································・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer joint 16・ Cage 18 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Torque transmission ball 19 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Mouse part 21 ・ ・ ・ ・ ・ ・··· Shaft 21b ·················································· •・ ・ ・ ・ ・ Seal member 24, 30 ... Labyrinth seal 27 ... ·········· Seal plate 29a ················· Side lip 29b, 29c ········ Radial lip 50 ··· ... Angular contact ball bearings 51 ... Outer ring 51a ... Annular projection 51b, 51c ··· Outer rolling surface 51d ··············· Flange 51e 53 ·············· Inner rings 52a, 53a ··· Curved shoulders 52b and 53b ····· Inner rolling surfaces 52c and 53c ····························································· ... 56 ... Ball 57 ... Retainer 59 ...・ Weight 60 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Adhesive T1 ・ ・ ・ ・ ・ ・ ・ ・ Wall thickness T2 ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ Wall thickness of the inner rolling surface

Claims (7)

An outer member in which a double-row arc-shaped outer rolling surface is integrally formed on the inner periphery;
A pair of inner rings each having an arcuate inner rolling surface facing the double row outer rolling surface on the outer periphery;
A double row of balls accommodated between both rolling surfaces of the inner ring and the outer member;
A seal attached to an opening of an annular space formed between the outer member and the inner ring,
In the wheel bearing that constitutes the back-to-back type double row angular contact ball bearing in which the small diameter side end surfaces of the pair of inner rings collide in a butted state,
The outer member and the inner ring are formed from pipe material by plastic working, and the inner ring has a shoulder portion extending in the axial direction from the large diameter side of the inner rolling surface thereof, and extends radially outward from the shoulder portion. A wheel bearing, wherein a side plate portion is formed, and the side plate portion and the seal are opposed to each other through a slight gap to form a labyrinth seal.   The wheel bearing according to claim 1, wherein the outer member and the inner ring are formed by cold rolling.   The seal includes a metal core fitted to the cylindrical portion of the outer member, and a seal member having a pair of radial lips that are integrally joined to the metal core and slidably contact the shoulder of the inner ring. The wheel bearing according to claim 1 or 2, wherein a labyrinth seal is formed by confronting the seal member and the side plate portion with a slight axial clearance.   The seal is a cored bar fitted into the cylindrical part of the outer member, a pair of radial lips that are integrally joined to the cored bar and slidably contacted with a shoulder part of the inner ring, and inclined radially outward The side lip is in sliding contact with the side plate portion, and the outer edge of the side plate portion and the core metal face each other through a slight radial clearance. The wheel bearing according to claim 1, wherein a seal is formed.   The wheel bearing according to any one of claims 1 to 4, wherein the both rolling surfaces and the shoulder portion of the inner ring are formed with a predetermined size and accuracy by grinding.   The wheel bearing according to any one of claims 1 to 5, wherein a thickness of the side plate portion is set to be thinner than a thickness of the inner rolling surface. A hub wheel integrally having a wheel mounting flange for mounting a wheel on one end, and a small-diameter step portion extending in the axial direction from the wheel mounting flange via a shoulder; and
The wheel bearing according to any one of claims 1 to 6, wherein the wheel bearing is press-fitted into a small-diameter step portion of the hub wheel through a predetermined shimoshiro.
An outer joint member of a constant velocity universal joint is fitted into the hub ring via a serration, a fixing nut is attached to a male screw formed at an end of the serration, and the pair of inner rings are connected to shoulders of the hub ring. A predetermined bearing preload is applied by tightening the fixing nut with a predetermined tightening torque in a state of being sandwiched between a portion and a shoulder portion of the outer joint member.

Images