JP4812112B2 - 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, and more particularly to a wheel bearing device that improves the sealing performance of a seal.

  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. On the other hand, double row tapered roller bearings are used in vehicles such as off-road cars and trucks that have a heavy vehicle body weight.

  Since these wheel bearing devices are disposed at sites where muddy water or the like is easily applied, a seal is attached to an opening of an annular space formed between the outer member and the inner member. Among these seals, as a seal with particularly high sealing performance, a seal member provided with a seal lip is attached to an outer member serving as a stationary member, and the seal lip is slidably contacted with a slinger attached to the inner member. So-called high pack seals are commonly used.

  Various types of high pack seals have been proposed in the past, and a typical example of such a seal is shown in FIG. This seal seals between the inner peripheral side member 51 composed of a bearing inner ring or the like that rotates relative to the outer peripheral side member 52 composed of a bearing outer ring or the like, and is attached to the inner peripheral side member 51 and the outer peripheral side member 52, respectively. It consists of an annular sealing plate 53 and a sealing element 54 having an L-shaped cross section facing each other.

  The seal plate 53 is formed with a cylindrical portion 53a press-fitted into the outer diameter surface of the inner peripheral side member 51, a standing plate portion 53b rising from the cylindrical portion 53a, and an inwardly inclined tip at the standing plate portion 53b. And an inclined plate portion 53c. The seal plate 53 serves as a slinger and is formed from a steel plate by pressing.

  The sealing element 54 is a steel plate 55 having an L-shaped cross section provided with an elastic body 56 such as rubber or synthetic resin, and the cylindrical portion 55 a of the substrate 55 is press-fitted into the inner diameter surface of the outer peripheral member 52. Is attached by. The standing plate portion 55b of the substrate 55 has an inclined piece portion 55c inclined inward at the tip. The elastic body 56 is provided so as to cover the inside of the substrate 55, and includes first and second side lips 56a and 56b, and one radial lip 56c.

  The first side lip 56a extends from the upright plate portion 55b of the substrate 55 to the oblique outer diameter side, the tip thereof is in sliding contact with the inclined plate portion 53c of the seal plate 53, and the second side lip 56b is connected to the upright plate portion 55b. The tip extends from the vicinity of the tip to the oblique outer diameter side and the tip is in sliding contact with the standing plate portion 53 b of the seal plate 53. On the other hand, the radial lip 56 c extends from the tip of the standing plate portion 55 b to the oblique inner diameter side opposite to the standing plate portion 53 b of the seal plate 53, and the tip is in sliding contact with the cylindrical portion 53 a of the seal plate 53.

  The muddy water or the like scattered on the seal 50 adheres to the outer surface of the first side lip 56a that is in sliding contact with the inner surface of the seal plate 53, but the inclined plate portion 53c is provided on the outer diameter portion of the standing plate portion 53b of the seal plate 53. Therefore, the space S in which muddy water or the like accumulates can be kept as small as possible. Therefore, it is alleviated that the sealing function of the first side lip 56a is lowered by foreign matters such as mud and sand contained in the muddy water.

When the inner peripheral side member 51 is on the rotation side, the action of removing the moisture or foreign matter in the muddy water in the seal space S by centrifugal force and quickly removing it without lowering the sealing force can be obtained. Thereby, when muddy water infiltrates inward, higher sealing performance is obtained by the second side lip 56b slidably contacting the seal plate 53 on the inner diameter side than the first side lip 56a. Further, since the radial lip 56c is located further inside than this, the infiltration of muddy water and the like from the outside is tripled and a sealing action against the internal lubricant is obtained.
Japanese Patent Laid-Open No. 9-292032

  In such a conventional seal 50, the water and the like of the muddy water in the space S of the seal 50 is shaken off by the centrifugal force, and even if the muddy water enters inside, the first and second side lips 56a and 56b, The inner radial lip 56c prevents the intrusion of muddy water from the outside in triplicate and provides a high sealing action. However, particularly in a vehicle that is operated in a poor environment such as an off-road car or a pickup truck, the muddy water performance is insufficient even with the seal 50 having such a configuration, and further improvement in sealing performance is required.

  This invention is made | formed in view of such a situation, and aims at the improvement of the sealing performance of a seal | sticker, and it aims at providing the wheel bearing apparatus which can maintain bearing performance over a long period of time. .

In order to achieve such an object, the invention according to claim 1 of the present invention has a vehicle body mounting flange integrally attached to the suspension on the outer periphery, and a double row outer rolling surface integrally on the inner periphery. A hub wheel having a formed outer member and a wheel mounting flange for mounting a wheel at one end and having a small-diameter step portion formed on the outer periphery, and a small-diameter step portion of the hub wheel. An inner member comprising at least one inner ring and formed on the outer periphery with a double-row inner rolling surface facing the double-row outer rolling surface, and both rolling surfaces of the inner member and the outer member For a wheel provided with a double row rolling element accommodated in a rollable manner via a cage, and a seal attached to an opening of an annular space formed by the outer member and the inner member In the bearing device, the inner seal of the seals has a substantially L-shaped cross section. In other words, the annular member is pressed into the outer periphery of the inner ring, and the annular seal plate that is arranged oppositely and that is press-fitted into the inner periphery of the end portion of the outer member and the seal member that is integrally joined to the core member. It is composed of a composite type seal made of slinger, and the seal member has a side lip that is in sliding contact with the slinger, and a backup seal is provided on the outer side of the seal, and this backup seal is connected to the outer member. A cored bar provided with a cylindrical fitting part press-fitted into the outer periphery of the end part, and a disk part extending radially inward from the fitting part along the end surface of the outer member, and the cored bar It consists seal member integrally joined to the base of the seal member has a sliding contact with the seal lip on the outer surface of the slinger extends inclined radially inwardly together, the backup seal sealing member , Is opposed to the sealing member in the sealing plate, tongues projecting axially on one of these base and the sealing member is formed, the tongue is in elastic contact with the other member.

Thus, in the wheel bearing device having the second or third generation structure provided with the seal attached to the opening of the annular space formed by the outer member and the inner member, the inner seal among the seals is provided. However, an annular seal plate comprising a cored bar that is disposed opposite to each other with a substantially L-shaped cross section and press-fitted into the inner periphery of the end of the outer member, and a seal member that is integrally joined to the cored bar, And a composite seal composed of a slinger press-fitted to the outer periphery of the inner ring, the seal member has a side lip that slidably contacts the slinger, and a backup seal is provided on the outer side of the seal. A mandrel comprising a cylindrical fitting portion press-fitted into the outer periphery of the end portion of the outer member, and a disc portion extending radially inward from the fitting portion along the end surface of the outer member; Bonded integrally to this mandrel Consists seal member, the seal member has a sliding contact with the seal lip on the outer surface of the slinger extends inclined radially inwardly together, the base of the seal member of the backup seal, the seal plate A tongue piece projecting in the axial direction is formed on one of the base and the seal member and is opposed to the seal member, and this tongue piece is in elastic contact with the other member, so that rainwater, dust, etc. directly enter the seal. Thus, even when used in a poor environment, it is possible to provide a wheel bearing device capable of improving the sealing performance of the seal and maintaining the bearing performance for a long period of time. In addition, muddy water that has passed through the side lip of the backup seal can be prevented from entering between the outer member and the cored bar. Intrusion into the interior can be prevented.

  According to a second aspect of the present invention, the core of the backup seal has a disc portion that is in close contact with the end portion of the outer member, and an inner end that extends further radially inward from the disc portion. The seal member may be joined to the inner end portion.

It is preferable as defined in claim 3, the base of the seal member of the backup seal, if it is bonded wraps around the disc portion so as to be in close contact with the end face of the outer member, Ba click up seal It is possible to prevent the muddy water that has passed through the side lip from entering between the outer member and the cored bar, and the muddy water rusts the outer member and the muddy water enters the bearing from the fitting portion. Can be prevented.

  According to a fourth aspect of the present invention, the inner member includes the hub ring and a pair of inner rings press-fitted into a small-diameter step portion of the hub ring. However, if the backup seal is provided on the outer side of the seal, the sealing performance of the seal is further improved, and the bearing performance can be maintained for a long period of time.

Moreover, if the core metal of the said backup seal is formed by the press work from the steel plate which has rust prevention ability like invention of Claim 5, it will prevent rusting over a long period of time and will be stable. Sealing performance can be maintained. Further, as in the invention described in claim 6, if the base part of the seal member of the backup seal extends to the inner diameter side of the outer diameter of the standing plate part of the slinger, muddy water that has passed through the side lip, etc. Intrusion between the outer member and the cored bar can be reliably prevented.

A wheel bearing device according to the present invention has an outer member integrally formed with a vehicle body mounting flange for mounting to a suspension device on the outer periphery, and an outer member formed integrally with a double row outer rolling surface on the inner periphery, and one end It has a wheel mounting flange for mounting the wheel on the part, a hub wheel with a small diameter step formed on the outer periphery, and at least one inner ring fitted to the small diameter step of this hub wheel, An inner member in which a double row inner rolling surface facing the outer row rolling surface of the double row is formed, and rolling between the both rolling surfaces of the inner member and the outer member via a cage. A wheel bearing device comprising: a double row of rolling elements accommodated freely; and a seal attached to an opening of an annular space formed by the outer member and the inner member. The side seals are arranged opposite each other with a substantially L-shaped cross section, A composite type seal composed of a core bar press-fitted into the inner periphery of the end of the member, an annular seal plate composed of a seal member integrally joined to the core metal, and a slinger press-fitted into the outer periphery of the inner ring. The seal member has a side lip that is in sliding contact with the slinger, a backup seal is provided on the outer side of the seal, and the backup seal is pressed into the outer periphery of the end of the outer member. A cored bar having a fitting part, a disk part extending radially inward from the fitting part along the end face of the outer member, and a seal member integrally joined to the cored bar. the sealing member has a sliding contact with the seal lip on the outside surface of the slinger extends inclined radially inwardly together, the base of the seal member of the backup seal, sheet in the sealing plate Is opposed to the seal member, the tongue projecting in the axial direction on one of these base and the sealing member is formed, since the tongue piece is in elastic contact with the other member, rainwater or dusts directly entering the seal Thus, even when used in a poor environment, it is possible to provide a wheel bearing device capable of improving the sealing performance of the seal and maintaining the bearing performance for a long period of time. In addition, muddy water that has passed through the side lip of the backup seal can be prevented from entering between the outer member and the cored bar. Intrusion into the interior can be prevented.

  An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for attaching a wheel to one end And a hub wheel in which an inner rolling surface facing one of the outer rolling surfaces of the double row is formed on the outer periphery, and a small diameter step portion extending in the axial direction from the inner rolling surface, and the hub An inner member comprising an inner ring press-fitted into a small-diameter step portion of the ring and having an inner rolling surface facing the other of the outer row rolling surfaces of the double row on the outer periphery; and the inner member and the outer member A double row rolling element accommodated between the rolling surfaces via a cage, and a seal attached to an opening of an annular space formed by the outer member and the inner member. In the wheel bearing device provided, the inner seal of the seals has a substantially L-shaped cross section. And an annular seal plate composed of a core bar press-fitted into the inner periphery of the end portion of the outer member and a seal member integrally joined to the core bar, and press-fitted into the outer periphery of the inner ring. The seal member has a pair of side lips that are in sliding contact with the slinger, and a backup seal is provided on the outer side of the seal. A cored bar provided with a cylindrical fitting part press-fitted into the outer periphery of the end part of the side member, and a disk part extending radially inward from the fitting part along the end surface of the outer member, and A seal member integrally joined to the mandrel, extending inwardly in the radial direction and having a seal lip integrally slidably contacting the outer surface of the slinger, wherein the base of the seal member of the backup seal is Around the disc portion and joined so as to be in close contact with the end face of the outer member, the base portion is disposed opposite to the seal member in the seal plate, and a tongue piece protruding in the axial direction is formed on the seal member. It is in elastic contact with the base.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing device according to the present invention, and FIG. 2 is an enlarged view of a main part showing a seal portion of 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 is for a drive wheel called the second generation, and comprises a hub wheel 1 and a wheel bearing 2. The wheel bearing 2 includes an outer member 3 and a pair of inner rings 5 and 5 that are fitted through double-row rolling elements (conical rollers) 4 and 4.

  The hub wheel 1 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at one end, and a cylindrical small-diameter step portion 1a extending in the axial direction from the wheel mounting flange 6 is formed on the outer periphery. A serration (or spline) 1b for torque transmission is formed on the inner periphery. Hub bolts 6a are planted on the wheel mounting flange 6 at equal intervals in the circumferential direction. The wheel bearing 2 is press-fitted into the small-diameter step portion 1a of the hub wheel 1 through a predetermined shimiro, and a predetermined portion is formed by a caulking portion 1c formed by plastically deforming an end portion of the small-diameter step portion 1a radially outward. It is fixed in the axial direction with respect to the hub wheel 1 with the bearing preload applied.

  The hub wheel 1 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and an arcuate base portion 6b is formed on the inner side of the wheel mounting flange 6, and from the base portion 6b to the shoulder portion. The surface hardness is hardened to a range of 58 to 64 HRC by induction hardening over the small diameter step portion 1a through 1d. Thereby, it has sufficient mechanical strength with respect to the rotational bending load applied to the wheel mounting flange 6, and the fretting resistance of the small-diameter step portion 1 a serving as the fitting portion of the inner rings 5, 5 is improved.

  The outer member 3 integrally has a vehicle body mounting flange 3b to be attached to a knuckle (not shown) on the outer periphery, and has a tapered double row outer rolling surface 3a that opens outward on the inner periphery. 3a is integrally formed. This outer member 3 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least the double row outer rolling surfaces 3a and 3a have a surface hardness of 58 to 64 HRC by induction hardening. Hardened to range.

  On the other hand, on the outer periphery of the inner ring 5, the tapered inner rolling surface 5a facing the double row outer rolling surfaces 3a, 3a and the rolling element 4 are guided to the larger diameter side of the inner rolling surface 5a. A large collar 5b and a small collar 5c for preventing the rolling element 4 from falling off are formed on the small diameter side. The inner ring 5 and the rolling element 4 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core part by quenching. And the double-row rolling elements 4 and 4 are accommodated between both rolling surfaces of the outer member 3 and a pair of inner ring | wheels 5 and 5, and are hold | maintained by the holder | retainers 7 and 7 so that rolling is possible. The wheel bearing 2 is constituted by a so-called back-to-back type double row tapered roller bearing that abuts against the shoulder 1d of the hub wheel 1 and that the small flanges 5c of the inner ring 5 abut each other in a butted state.

  Further, seals 8 and 8 are attached to an opening of an annular space formed between the outer member 3 and the inner ring 5. These seals 8 and 8 prevent the grease sealed inside the bearing from leaking to the outside and preventing rainwater, dust, etc. from entering the bearing from the outside. As shown in an enlarged view in FIG. 2, the seal 8 is a so-called high pack seal, which is a composite seal composed of an annular seal plate 9 and a slinger 10 having a substantially L-shaped cross section and arranged to face each other. It is composed. The seal plate 9 includes a metal core 11 that is press-fitted into the inner periphery of the end of the outer member 3 and a seal member 12 that is integrally joined to the metal core 11 by vulcanization adhesion. The metal core 11 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). Further, the seal member 12 is made of an elastic member such as nitrile rubber and has a pair of side lips 12a and 12b and a radial lip 12c that are inclined and extended radially outward.

  On the other hand, the slinger 10 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). The cylindrical portion 10a is press-fitted into the outer diameter of the cylindrical portion 10a, and the upright plate portion 10b extends radially outward from the cylindrical portion 10a. Thereby, the slinger 10 has rust prevention ability and can prevent rusting over a long period of time. The pair of side lips 12a and 12b are in sliding contact with the standing plate portion 10b of the slinger 10, and the radial lip 12c is in sliding contact with the cylindrical portion 10a.

  In the present embodiment, a backup seal 13 is further press-fitted to the outer periphery of the end portion of the outer member 3. The backup seal 13 includes a metal core 14 and a seal member 15 that is integrally vulcanized and bonded to the metal core 14. The core 14 is formed in a cup shape 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), A cylindrical fitting portion 14a that is press-fitted and fixed to the outer periphery of the outer side end portion of the outer member 3, and extends radially inward from the fitting portion 14a and is in close contact with the outer side end portion of the outer member 3 The disc part 14b to be formed and the inner end part 14c extending further radially inward from the disc part 14b.

  On the other hand, the seal member 15 is integrally joined to the inner end portion 14c of the metal core 14 by vulcanization adhesion, and has a side lip 15a extending inclining radially inward. The side lip 15a is in sliding contact with the outer surface of the standing plate portion 10b of the slinger 10 to prevent rainwater, dust, and the like from directly entering the seal 8. Thereby, even if it uses in a poor environment, the sealing performance of the seal | sticker 8 can be improved and the wheel bearing apparatus which can maintain bearing performance over a long period of time can be provided.

  In addition, although the 2nd generation structure by the side of a driving wheel was illustrated here, the bearing device for wheels which concerns on this invention may be a driven wheel side not only in this but it is a 3rd generation structure. Also good.

  FIG. 3 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention, FIG. 4 is an enlarged view of a main part showing the seal part of FIG. 3, and FIG. FIG. 6 is an enlarged view of an essential part showing a modification of the seal part of FIG. Note that the same parts and parts as those in the first embodiment described above or parts having the same functions are denoted by the same reference numerals and detailed description thereof is omitted.

  This wheel bearing device is for a drive wheel referred to as a third generation, and includes a hub wheel 16 and a double row rolling bearing 17 as a unit. The double-row rolling bearing 17 includes an outer member 18 and an inner member 20 that is fitted into the outer member 18 via double-row rolling elements (balls) 19 and 19. The inner member 20 includes a hub ring 16 and an inner ring 21 fixed to the hub ring 16.

  The hub wheel 16 integrally has a wheel mounting flange 6 at an end portion on the outer side, an arcuate outer side inner rolling surface 16a on the outer periphery, and a cylindrical shape extending in the axial direction from the inner rolling surface 16a. A small-diameter step 16b is formed, and a serration (or spline) 1b for torque transmission is formed on the inner periphery. The inner ring 21 has an inner-side arcuate inner rolling surface 21a formed on the outer periphery, and is press-fitted into the small-diameter step portion 16b of the hub wheel 16 via a predetermined shimoshiro.

  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 has a surface hardness by induction quenching from the inner rolling surface 16a to the small diameter step portion 16b from the base portion 6b. Is cured in the range of 58 to 64 HRC. Further, the inner ring 21 and the rolling element 19 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core portion by quenching. As a result, the strength and rigidity of the hub wheel 16 can be increased and the weight and size can be reduced, and the hub wheel 16 has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 6. The fretting resistance of the small-diameter step portion 16b is improved.

  The outer member 18 integrally has a vehicle body mounting flange 3b on the outer periphery, and has an arcuate double row outer rolling surface facing the double row inner rolling surfaces 16a and 21a of the inner member 20 on the inner periphery. 18a and 18a are integrally formed. This outer member 18 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least double row outer rolling surfaces 18a and 18a have a surface hardness of 58 to 64 HRC by induction hardening. Hardened to range.

  Double row rolling elements 19 and 19 are accommodated between both rolling surfaces of the outer member 18 and the inner member 20, and are held by the cages 22 and 22 so as to be freely rollable. This double row rolling bearing 17 is constituted by a so-called back-to-back type double row angular contact ball bearing in which the small diameter (front) side end surface 21b of the inner ring 21 abuts with the shoulder portion 16c of the hub wheel 16 in a butted state. .

  Further, seals 23 and 24 are attached to an opening portion of an annular space formed between the outer member 18 and the inner member 20. These seals 23 and 24 prevent leakage of grease sealed inside the bearing and intrusion of rainwater and dust from the outside into the bearing.

  As shown in an enlarged view in FIG. 4, the inner-side seal 24 constitutes a composite high pack seal composed of an annular seal plate 26 and a slinger 10 which are substantially L-shaped in cross section and arranged to face each other. is doing. The seal plate 26 includes a metal core 11 that is press-fitted into the inner periphery of the end of the outer member 18, and a seal member 27 that is integrally joined to the metal core 11 by vulcanization adhesion. The seal member 27 is made of an elastic member such as nitrile rubber, and is joined from the end portion of the cored bar 11 to the inner diameter portion. A pair of side lips 12a, 12b and a radial lip 12c extending in a radially outward direction and a tongue piece 27a formed so as to protrude in the axial direction at the end of the core metal 11 are integrally provided.

  In this embodiment, a backup seal 28 is press-fitted to the outer periphery of the inner side end of the outer member 18. The backup seal 28 includes a core metal 29 and a seal member 30 that is integrally vulcanized and bonded to the core metal 29. The core metal 29 is formed into an L-shaped cross section by press working from an austenitic stainless steel plate (JIS standard SUS304, etc.) or a rust-proof cold rolled steel plate (JIS standard SPCC, etc.). A cylindrical fitting portion 29a that is press-fitted and fixed to the outer periphery of the end portion of the outer member 18, and a disc portion 29b that extends radially inward from the fitting portion 29a along the end surface of the outer member 18. Consists of.

  On the other hand, the seal member 30 is made of an elastic member such as nitrile rubber, and is integrally joined to the disc portion 29b of the core metal 29 by vulcanization adhesion. The seal member 30 extends so as to incline radially inward from the base portion 30a and the base portion 30a which are joined by being wrapped around the disc portion 29b of the core metal 19 so as to be in close contact with the end face of the outer member 18. It has a side lip 30b. The side lip 30b is in sliding contact with the outer surface of the standing plate portion 10b of the slinger 10 to prevent muddy water or the like from directly entering the seal 24. Further, the tongue piece 27 a of the seal member 27 in the seal plate 26 is in elastic contact with the base portion 30 a of the seal member 30 in the backup seal 28, and muddy water or the like that has passed through the side lip 30 b is formed between the outer member 18 and the core metal 29. Preventing intrusion in between.

  That is, in the backup seal 13 in the first embodiment described above, when muddy water or the like that has passed through the side lip 15a enters between the outer member 3 and the core metal 14 as shown in FIG. The direction member 3 is rusted, and this rust is promoted, so that muddy water may enter the bearing from the fitting portion. In the present embodiment, by employing the backup seal 18 having such a configuration, the sealing performance of the seal 24 can be further improved and the bearing performance can be maintained over a long period of time even when used in a poor environment. .

  FIG. 6 shows a modification in which the configurations of the seal 24 and the backup seal 28 in FIG. 4 are partially different. In this embodiment, a backup 31 is added to the seal 8 attached to the inner side end of the outer member 18. The backup seal 31 includes a metal core 29 and a seal member 32 that is integrally vulcanized and bonded to the metal core 29. The sealing member 32 is integrally joined to the disc portion 29b of the core metal 29 by vulcanization adhesion, and a base portion that is joined around the disc portion 29b of the core metal 29 so as to be in close contact with the end surface of the outer member 18. 32a, and a side lip 30b extending obliquely inward in the radial direction from the base portion 32a. In addition, a tongue piece 33a that elastically contacts the seal member 12 of the seal plate 9 is projected from the base portion 32a. As a result, muddy water or the like that has passed through the side lip 30b is prevented from entering between the outer member 18 and the core metal 29, and the airtightness of the backup seal 31 is increased and the sealing performance of the seal 8 is further improved. be able to.

  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 wheel bearing device having a second or third generation structure in which a seal is mounted on a bearing end portion, regardless of whether the wheel is used for a driving wheel or a driven wheel.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. It is a principal part enlarged view which shows the seal part of the inner side of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the seal part of the inner side of FIG. It is explanatory drawing which shows the malfunction state of the seal | sticker part of FIG. It is a principal part enlarged view which shows the modification of the seal | sticker of FIG. It is a principal part enlarged view which shows the seal | sticker in the conventional wheel bearing apparatus.

Explanation of symbols

1, 16 ··········································································· Serration 1c ····························································· For wheels Bearings 3, 18, ... Outer members 3a, 18a ... Outer rolling surface 3b ... · Body mounting flanges 4, 19 ·········· Rolling elements 5, 21 ·········· Inner rings 5a, 16a, 21a ··· Inward rolling Running surface 5b ············································································ ..Wheel mounting flange 6a ... hub bolts 6b, 30a, 32a ... Base 7, 22, ... Retainer 8, 23, 24 ... Seal 9, 26 ... ... Seal plate 10 ... Slinger 10a ... Cylindrical part 10b ...・ Standing plate parts 11, 14, 29... Core bars 12, 15, 27, 30, 32 .. Seal members 12a, 12b, 15a, 30b. Side lip 12c.・ ・ ・ ・ Radial lip 13, 28, 31 ・ ・ ・ ・ ・ ・ Backup seal 14a ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Fitting part 14b ・ ・ ・ ・ ・ ・· · · Disk portion 14c · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · .... Inward part 21b ········· Small end surface 27a, 33 ·····················································・ ・ ・ ・ ・ ・ ・ ・ Inner peripheral side member 52 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Outer peripheral member 53 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・Seal plates 53a, 55a,... Cylindrical portions 53b, 55b,... Standing plate portions 53c,. ············· Sealing element 55 ···························· ... Elastic body 56a ... First side lip 56b ... Second Side lip 56c ... Radial lip S ... ···········space

Claims (6)

An outer member integrally having a vehicle body mounting flange to be attached to the suspension device on the outer periphery, and an outer rolling surface of a double row integrally formed on the inner periphery;
Consists of a hub ring integrally having a wheel mounting flange for mounting a wheel at one end, a small-diameter step portion formed on the outer periphery, and at least one inner ring fitted to the small-diameter step portion of the hub ring. An inner member formed with a double-row inner rolling surface facing the double-row outer rolling surface,
A double row rolling element housed between the rolling surfaces of the inner member and the outer member so as to be freely rollable via a cage;
In the wheel bearing device provided with a seal attached to an opening of the annular space formed by the outer member and the inner member,
Among the seals, the inner side seals are arranged to face each other with a substantially L-shaped cross section, and the core metal press-fitted into the inner periphery of the end of the outer member, and the seal integrally joined to the core metal The seal member is composed of an annular seal plate made of a member and a composite type seal made of a slinger press-fitted to the outer periphery of the inner ring, and the seal member has a side lip that slidably contacts the slinger, and the outside of the seal A backup seal is provided on the side, and the backup seal is a cylindrical fitting portion that is press-fitted into the outer periphery of the end portion of the outer member, and a radially inner portion along the end surface of the outer member from the fitting portion. And a seal member integrally joined to the core, and the seal member extends inward in the radial direction and slides on the outer surface of the slinger. Seal Has-up together, the base of the seal member of the backup seal, the disposed opposite to the seal member of the seal plate, tongues projecting axially on one of these base and the sealing member is formed, the tongue A bearing device for a wheel, wherein the piece is in elastic contact with the other member .   The core of the backup seal is composed of a disc portion that is in close contact with the end portion of the outer member, and an inner end portion that extends further radially inward from the disc portion, and the seal member is disposed on the inner end portion. The wheel bearing device according to claim 1, wherein: It said backup base of the seal of the sealing member is a wheel bearing apparatus of claim 1, which is bonded wraps around the disc portion so as to be in close contact with the end face of the outer member.   The inner member includes the hub ring and a pair of inner rings press-fitted into a small-diameter step portion of the hub ring, and an outer seal of the seals is configured by the inner seal. The wheel bearing device according to claim 1, wherein the backup seal is provided on an outer side.   The wheel bearing device according to any one of claims 1 to 4, wherein the core metal of the backup seal is formed by press working from a steel plate having antirust performance. The wheel bearing device according to any one of claims 1 to 5, wherein a base portion of the seal member of the backup seal extends to an inner diameter side with respect to an outer diameter of the standing plate portion of the slinger.

Images