JP2008163979A - Wheel bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighter, compacter and more inexpensive wheel bearing device. <P>SOLUTION: The wheel bearing device having a wheel mounting flange 5 at one end comprises a hub ring 1 having a small diameter stepped portion 1b formed on the outer periphery, and a wheel bearing 2 pressed therein. The wheel bearing 2 consists of an outward member 7 having double-row outside rolling surfaces 7a formed on the inner periphery, a pair of inner rings 8, 9 having inside rolling surfaces 8a, 9a opposed to the double-row outside rolling surfaces 7a, double-row balls 11 stored between both rolling surfaces, and a pair of seals 15 mounted in opening portions between the outward member 7 and each of the inner rings 8, 9. The outward member 7 and the inner rings 8, 9 are formed from steel plates with plastic work, and a shoulder portion 14 is formed at one end of each of the inner rings 8, 9 extending outward to the radial direction. The seal 15 is integrally joined to the shoulder portion 14 with vulcanizing adhesion. Cylindrical portions 13 are formed at both ends of the outward member 7, and the seal 15 is put in sliding contact therewith. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wheel bearing device that rotatably supports a wheel of a vehicle such as an automobile, and more particularly to a wheel bearing device that achieves a reduction in cost while being lightweight and compact.

  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 (outer member) are formed by pressing from a steel plate is known. For example, the angular ball bearing 50 shown in FIG. 5 is used in a magnetic hard disk device or the like, but the outer ring 51 and the pair of inner rings 52 and 53 are formed from a stainless steel plate by pressing or rolling.

  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 a press is used as a wheel bearing, a sealing device (not shown) is formed between the outer ring 51 and the inner rings 52 and 53 in order to ensure sealing performance. Although it is necessary to attach to the opening of the space, not only the number of parts increases, but also a structural change for securing the sealing space is unavoidable, and the number of assembly steps increases along with the processing cost, and the cost increase cannot be denied.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a wheel bearing device that is reduced in cost and weight while being compact.

  In order to achieve such an object, the invention according to claim 1 of the present invention integrally has an outer member having a double row outer rolling surface formed on the inner periphery and a wheel mounting flange at one end. A hub wheel formed with a small-diameter step portion extending in the axial direction from the wheel mounting flange, and an inner member comprising at least one inner ring press-fitted into the small-diameter step portion of the hub wheel via a predetermined shimiro, A pair of rolling elements housed between both rolling surfaces of the inner member and the outer member, and a pair attached to an opening of an annular space formed between the inner member and the outer member The outer bearing member and the inner member are formed from a steel plate by plastic working, and at least one of the pair of seals is the outer member or the inner member. It is integrally joined to one of the members .

  Thus, in the wheel bearing device of the 1st thru / or 3rd generation structure constituted by the hub wheel which has a wheel mounting flange in one end integrally, and a double row rolling bearing, an outer member and an inner member are steel plates. Since at least one of the pair of seals is integrally joined to either the outer member or the inner member, the number of parts can be reduced and the number of assembly steps can be reduced. Can be significantly reduced, and the cost can be reduced.

  Preferably, as in the invention described in claim 2, if the seal is made of an elastomer and is joined by vulcanization adhesion and is slidably contacted with the other member facing, the desired sealability can be secured. it can.

  According to a third aspect of the present invention, a shoulder portion extending radially outward is formed at one end portion of the inner ring, the seal is joined to the shoulder portion, and both end portions of the outer member are formed. A cylindrical portion may be formed on the cylindrical portion, and the seal may be slidably contacted with the cylindrical portion, and may extend radially inward at both ends of the outer member as in the invention according to claim 4. A shoulder is formed, and the seal is joined to the shoulder, and a cylindrical shoulder extending in the axial direction is formed at one end of the inner ring, and the seal is in sliding contact with the shoulder. good.

  Further, as in the invention according to claim 5, one inner rolling surface facing the outer rolling surface of the double row is directly formed on the outer periphery of the hub wheel, and a shoulder portion is formed from the inner rolling surface. The inner diameter of the inner ring is formed on the outer periphery of the inner ring, the other inner rolling surface facing the outer rolling surface of the double row is formed, and the end surface on the small diameter side is in contact with the shoulder. If it is abutted, the strength and rigidity of the hub wheel can be increased, and the device can be reduced in weight and size.

  The wheel bearing device according to the present invention integrally has an outer member having a double row outer raceway formed on the inner periphery and a wheel mounting flange at one end, and extends in an axial direction from the wheel mounting flange. A hub ring formed with a small-diameter step portion, an inner member comprising at least one inner ring press-fitted into the small-diameter step portion of the hub ring via a predetermined shimeshiro, and both the inner member and the outer member A wheel bearing device comprising: a double row of rolling elements housed between rolling surfaces; and a pair of seals attached to an opening of an annular space formed between the inner member and the outer member. The outer member and the inner member are formed from a steel plate by plastic working, and at least one of the pair of seals is integrally joined to either the outer member or the inner member. As productivity increases, May accumulate step, also, the number of parts can be reduced, assembling steps can be greatly reduced, it is possible to reduce the cost.

  It consists of a hub wheel integrally formed with a wheel mounting flange at one end, a small diameter step portion extending in the axial direction from the wheel mounting flange, and a double row rolling bearing press-fitted into the small diameter step portion of the hub ring. A wheel bearing, wherein the wheel bearing is formed with an outer member having a double-row outer rolling surface formed on an inner periphery and an inner rolling surface opposed to the double-row outer rolling surface. A pair of inner rings, a double row rolling element housed between the rolling surfaces, and a pair of seals mounted in an opening of an annular space formed between the outer member and the inner ring. In the wheel bearing device provided, a shoulder portion extending radially outward is formed at one end portion of the inner ring, and the seal is integrally joined to the shoulder portion by vulcanization bonding, and both ends of the outer member A cylindrical portion is formed on the portion, and the seal is in sliding contact with the cylindrical portion.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention, FIG. 2 (a) is a longitudinal sectional view showing a single outer member of FIG. 1, and FIG. 1 (b) is a single inner ring. 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, 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 detachably integrated via a fixing nut 4.

  The hub wheel 1 has a wheel mounting flange 5 for mounting a wheel (not shown) at one end portion on the outer side, and a cylindrical shape extending from the wheel mounting 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. This hub wheel 1 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the surface hardness is in the range of 58 to 64 HRC by induction hardening from the shoulder 1a to the small diameter step 1b. Has been cured.

  The wheel bearing 2 is fitted into the knuckle 6, the outer member 7 is formed with double row outer rolling surfaces 7 a, 7 a on the inner periphery, and the outer surface 7 a, 7 a of these double rows is formed on the outer periphery. A pair of inner rings 8 and 9 formed with opposed inner rolling surfaces 8a and 9a, and double row rolling elements (balls) accommodated between the rolling surfaces via cages 10 and 10 so as to roll freely. 11 and 11. The end faces 8b and 9b on the small diameter (front) side of the inner rings 8 and 9 abut each other in a butted state to constitute a so-called back-to-back type double row angular ball bearing.

  The outer member 7 and the inner rings 8 and 9 are formed by pressing or rolling (hereinafter referred to as plastic working) a steel plate made of carburized steel such as SCr420 and SCM415 having a relatively small amount of carbon. And the surface hardness is hardened in the range of 50 to 64 HRC by carburizing and quenching. Other examples of the material of the outer member 7 and the inner rings 8, 9 include carbon steel such as SCM440, cold rolled steel plate (JIS standard SPCC system, etc.), S45C, and the like. In the case of cold rolled steel or carbon steel, at least the outer member 7 has double-row outer rolling surfaces 7a and 7a, and inner rings 8 and 9 have inner rolling surfaces 8a and 9a having surface hardness by induction hardening. Curing treatment is performed in the range of 50 to 64 HRC to improve the rolling fatigue life. In addition, these rolling surfaces are subjected to grinding and superfinishing as necessary.

Next, the configuration of the outer member 7 and the inner rings 8, 9 will be described in detail with reference to FIG.
The outer member 7 is formed into a cylindrical shape by punching a rolled steel plate into a disk-shaped material having a predetermined outer diameter, and this material is formed into a cup shape by deep drawing, and then punching out the bottom. . And as shown to (a), the cyclic | annular convex part 12 which protrudes to a radial inside is formed in the internal peripheral surface of this cylindrical raw material by plastic working. Further, double-row outer rolling surfaces 7a and 7a are formed on both sides of the annular convex portion 12 by plastic working, and cylindrical portions 13 and 13 serving as seal land portions of a seal 14 described later are formed on both ends. The

  On the other hand, the inner ring 8 (9), like the outer member 7, is formed by punching a rolled steel sheet into a disk-shaped material having a predetermined outer diameter, and this material is formed into a cup shape by deep drawing. Is formed into a cylindrical shape. And as shown in (b), the outer peripheral surface of this cylindrical raw material is plastically processed to the inner rolling surface 8a (9a) and the shoulder extending radially outward from the inner rolling surface 8a (9a). Part 14 is formed.

  The shoulder portions 14, 14 of the inner rings 8, 9 are in contact with the shoulder portion 1 a of the hub wheel 1 and the constant velocity universal joint 3, and the hub wheel 1 is held between the shoulder portions 1 a and the constant velocity universal joint 3. It is press-fitted and fixed to the small diameter step 1b. A predetermined bearing preload is applied by tightening the fixing nut 4 with a predetermined tightening torque.

  Here, in this embodiment, the seal 15 is integrally joined to the shoulder portions 14 of the inner rings 8 and 9. That is, the seal 15 is made of an elastomer made of nitrile rubber or the like, has a pair of radial lips, and is integrally joined to the shoulder portion 14 by vulcanization adhesion. As shown in FIG. 1, leakage of grease sealed inside the bearing in sliding contact with the cylindrical portion 13 of the outer member 7 and prevention of foreign matter such as rainwater and dust from entering the bearing from the outside are prevented. ing. As a result, the desired sealing performance can be secured and the number of parts can be reduced, and the number of assembling steps can be greatly reduced, and the cost can be reduced.

  Further, in the present embodiment, the outer member 7 and the inner rings 8, 9 are formed by plastic working and are manufactured substantially without machining, so that productivity is improved and yield is improved and cost reduction is achieved. it can. Here, the double-row angular contact ball bearing using balls as the rolling elements 9 is illustrated as the wheel bearing 2, but the present invention is not limited thereto, and a double-row tapered roller bearing using tapered rollers as the rolling elements may be used. .

  FIG. 3 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention. In this embodiment, only the configuration of the hub wheel is partially different from that of the first embodiment described above, and other parts having the same parts or the same functions are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  This wheel bearing device has a third generation structure, and includes an outer member 7 and an inner member 17 including a hub ring 16 and an inner ring 9 press-fitted and fixed to the hub ring 16. A constant velocity universal joint 3 is fitted into the hub wheel 16 so as to be able to transmit torque, and the hub wheel 16 and the constant velocity universal joint 3 are detachably integrated via a fixing nut 4.

  The hub wheel 16 has a wheel mounting flange 5 for attaching a wheel (not shown) to one end portion on the outer side, and the outer side outer rolling surface of the double row outer rolling surfaces 7a and 7a on the outer periphery. An inner rolling surface 16a opposite to 7a and a cylindrical small diameter step portion 16b extending in the axial direction from the inner rolling surface 16a are formed, and a serration (or spline) 1c for torque transmission is formed on the inner periphery. Yes. The hub wheel 16 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C and the like, and from the flange base portion 5a serving as a seal land portion of the outer seal 18 described later, to the inner rolling surface 16a and the small diameter. The surface hardness is hardened to a range of 58 to 64 HRC by induction hardening over the stepped portion 16b.

  The inner ring 9 is press-fitted into the small-diameter step portion 16b of the hub ring 16, and the small-diameter side end surface 9b collides with the shoulder portion 16c of the hub ring 16 in abutting state to form a back-to-back type double row angular ball bearing. Yes. The shoulder 14 of the inner ring 9 is in contact with the shoulder 16c of the hub wheel 16 and the constant velocity universal joint 3, and the fixing nut 4 is tightened to a predetermined level while being sandwiched between the shoulder 1a and the constant velocity universal joint 3. A predetermined bearing preload is applied by tightening with the applied torque.

  Here, in this embodiment, a seal 15 is integrally joined to the shoulder portion 14 of the inner ring 9, and an elastomer seal 18 is attached to the outer cylindrical portion 13 of the outer member 7. These seals 15 and 18 are formed in such a manner that grease that is slidably brought into contact with the inner cylindrical portion 13 and the flange base portion 5a of the outer member 7 and leaked inside the bearing and that foreign matters such as rainwater and dust from the outside are inside the bearing. To prevent intrusion. As a result, the strength and rigidity of the hub wheel 16 can be increased, and a desired sealing property can be ensured to reduce the weight and size of the device.

  FIG. 4 is a longitudinal sectional view showing a third embodiment of the wheel bearing device according to the present invention. In addition, the same code | symbol is attached | subjected to the component same site | part or the site | part which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  This wheel bearing device has a first generation structure, and includes a hub wheel 1 and a wheel bearing 19 attached to the hub wheel 1. The wheel bearing 19 includes an outer member 20 having double row outer rolling surfaces 7a, 7a formed on the inner periphery, and an inner rolling surface 8a facing the double row outer rolling surfaces 7a, 7a on the outer periphery. , 9a, and a pair of inner rings 21, 22 and double row rolling elements 11, 11 accommodated between the rolling surfaces via the cages 10, 10, respectively.

  The outer member 20 and the inner rings 21 and 22 are formed by plastic working of steel plates made of carburized steel such as SCr420 and SCM415 having a relatively small amount of carbon. And the surface hardness is hardened in the range of 50 to 64 HRC by carburizing and quenching. In addition, these rolling surfaces are subjected to grinding and superfinishing as necessary.

  The outer member 20 has double rows of outer rolling surfaces 7a, 7a formed on the inner peripheral surface thereof, and a shoulder portion extending radially inward to the outer end side of the double rows of outer rolling surfaces 7a, 7a. 23 is formed by plastic working. Elastomeric seals 24, 24 are integrally joined to these shoulder portions 23 by vulcanization adhesion. The shoulder portion 23 is formed with a stepped portion 23a by machining, and is positioned by engaging with the collar portion 6a of the knuckle 6.

  On the other hand, the inner ring 21 (22) has an inner rolling surface 8a (9a) and a cylindrical shoulder 25 extending in the axial direction from the inner rolling surface 8a by plastic working on the outer peripheral surface, like the outer member 20. Is formed. The shoulder portions 25, 25 of the inner rings 21, 22 are in contact with the shoulder portion 1 a of the hub wheel 1 and the constant velocity universal joint 3, and the hub wheel is held between these shoulder portions 1 a and the constant velocity universal joint 3. It is press-fitted and fixed to one small diameter step 1b. A predetermined bearing preload is applied by tightening the fixing nut 4 with a predetermined tightening torque.

  Here, in this embodiment, the seals 24 and 24 are integrally joined to the shoulder portions 23 and 23 of the outer member 20, and these seals 24 and 24 are in sliding contact with the shoulder portions 25 and 25 of the inner rings 21 and 22. It prevents leakage of grease sealed inside the bearing and foreign matter such as rainwater and dust from the outside. As a result, the number of parts can be reduced, the number of assembling steps can be greatly reduced, and the cost can be reduced.

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

  The wheel bearing device according to the present invention is applied to a wheel bearing device having a first to third generation structure including a hub wheel integrally having a wheel mounting flange at one end and an inner ring press-fitted into the hub wheel. it can.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. (A) is a longitudinal cross-sectional view which shows the outer member single-piece | unit of FIG. (B) is the longitudinal cross-sectional view which shows an inner ring single-piece | unit as above. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a longitudinal cross-sectional view which shows the angular contact ball bearing of the structure where the conventional inner and outer ring | wheel was formed by press work.

Explanation of symbols

1, 16 ·························································· Shoulder portions 1b, 16b・ ・ ・ ・ ・ ・ ・ ・ ・ Serrations 2 and 19 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel bearings 3 ・ ・ ・ ・ ・ ・・ Constant velocity universal joint 4 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fixing nut 5 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Wheel mounting flange 5a ・ ・ ・............ Flange base 6 ......... Knuckle 6a ... 20 ... Outer member 7a ... Outer rolling surface 8, 9, 21, 22, ...・ ・ Inner rings 8a, 9a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner rolling surfaces 8b, 9b ・ ・ ・ ・ ・ ・・ ・ ・ ・ ・ Small diameter side end face 10 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Retainer 11 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Rolling element 12 ··············································································· Seal 17 .... Inner member 50 .... Angular contact ball bearing 51 ... Outer ring 51a ································· 51・ ・ ・ ・ Flange 51e ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Ring recess 52, 53 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Inner ring 52a, 53a ・ ・ ・ ・ ・ ・ ・ ・ ・・ Curved shoulders 52b, 53b .... Inner rolling surfaces 52c, 53 ····························································· ·························· 56 59 ... Weight 60 ... Adhesive

Claims (5)

An outer member having a double row outer raceway formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange at one end and a small-diameter step portion extending in the axial direction from the wheel mounting flange, and at least a small-diameter step portion of the hub wheel press-fitted through a predetermined squeezing An inner member consisting of one inner ring,
A double row rolling element housed between both rolling surfaces of the inner member and the outer member;
In a wheel bearing device comprising a pair of seals mounted in an opening of an annular space formed between the inner member and the outer member,
The outer member and the inner member are formed from a steel plate by plastic working, and at least one of the pair of seals is integrally joined to either the outer member or the inner member. A wheel bearing device characterized by comprising:   The wheel bearing device according to claim 1, wherein the seal is made of an elastomer, and is slidably contacted with the other member facing and bonded by vulcanization adhesion.   A shoulder portion extending radially outward is formed at one end portion of the inner ring, and the seal is joined to the shoulder portion, and cylindrical portions are formed at both end portions of the outer member, and the seal portion is formed on the cylindrical portion. The wheel bearing device according to claim 1, wherein is in sliding contact.   A shoulder portion extending radially inward is formed at both ends of the outer member, and the seal is joined to the shoulder portion, and a cylindrical shoulder portion extending in the axial direction is formed at one end portion of the inner ring. The wheel bearing device according to claim 1, wherein the seal is in sliding contact with the shoulder portion.   One inner rolling surface facing the outer rolling surface of the double row is directly formed on the outer periphery of the hub wheel, and the small diameter step portion is formed from the inner rolling surface via a shoulder, The inner ring is formed with the other inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and the small-diameter side end surface is abutted against the shoulder portion in a butted state. The wheel bearing device described.

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