JP2011256935A - Bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device for a wheel in which resistance to muddy water of a seal is secured and the cost of the seal is intended to be reduced.SOLUTION: The seal 9 is constituted of: a core metal 12 including a cylindrical-shape fitting part 12a pressedly inserted into the outer diameter of the inner wheel 5, a disk part 12b extending outward in a radial direction, and an outer diameter part 12c extending in an axial direction; and a seal member 13 of synthetic rubber having a pair of dust lips 13a, 13b integrally connected to the outer diameter part 12c by vulcanizing bonding and obliquely extending outward in the radial direction, a grease lip 13c obliquely extending to the inside of the bearing, and a covering part 13d for protecting the exposed surface of the core metal 12. The covering part 13d turns around the end of the fitting part 12a of the core metal 12 and elastically contacts with the outer diameter of the inner wheel 5, the end inner periphery 2c of the outside member 2 is formed into a curved line shape whose diameter gradually increases toward the end face, the dust lip 13a, 13b and the grease lip 13c are slidably contact with each other via a predetermined fastening margin.

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention 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 seal's muddy water resistance and ensures the sealing performance of the seal over a long period of time. It is.

  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 an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. Further, the 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. Second generation structure in which body mounting flange or wheel mounting flange is formed directly on the outer periphery of the member, third generation structure in which one inner rolling surface is directly formed on the outer periphery of the hub wheel, or hub wheel, etc. 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 speed universal joint.

  These bearing portions are fitted with seals to prevent leakage of grease sealed inside the bearings and to prevent intrusion of rainwater, dust and the like from the outside. In recent years, the maintenance of automobiles has become more maintenance-free, and even longer bearing life has been demanded for wheel bearing devices. However, there are many cases in which rainwater, dust, or the like intrudes into the bearing and damages the bearing due to a sealing failure or a decrease in sealing performance. Therefore, it is possible to improve the bearing life by improving the sealing performance of the seal.

  Conventionally, various seals with improved sealing performance have been proposed. An example of such a seal is shown in FIG. The seal 50 is attached to the end portions of the outer member and the inner member that rotate relative to each other for the wheel bearing, and seals the opening of the annular space formed between the two members. The seal 50 includes a slinger 51 and an annular seal plate 52 that are arranged to face each other. The slinger 51 has a substantially L-shaped cross section formed by pressing from a steel plate, and a cylindrical portion 51a that is press-fitted into an inner member (inner ring) (not shown), and a standing portion that extends radially outward from the cylindrical portion 51a. It consists of a plate part 51b.

  On the other hand, the seal plate 52 is formed in a substantially L-shaped cross section, and includes a metal core 53 that is press-fitted into an inner periphery of an end of an outer member (not shown), and a seal member 54 that is vulcanized and bonded to the metal core 53. The seal member 54 is made of an elastic member, and has a pair of side lips 54a and 54b that are in sliding contact with the standing plate portion 51b of the slinger 51, and a grease lip 54c that is in sliding contact with the cylindrical portion 51a. The side lips 54 a and 54 b are formed to be inclined toward the outer diameter side, and the tips thereof are in sliding contact with the standing plate portion 51 b of the slinger 51 with a predetermined squeeze. A magnetic encoder 55 is integrally joined to the side surface of the standing plate portion 51b of the slinger 51 by vulcanization adhesion.

  Here, the distance d between the pair of side lips 54a and 54b is set to be 0.1 mm or more. Thereby, even when the cross-sectional height H of the seal 50 is lowered to 6 mm, the cross-sectional height H of the seal 50 can be lowered without deteriorating the muddy water resistance, and the wheel bearing can be made lighter and more compact. (For example, refer to Patent Document 1).

JP 2009-127790 A

  In such a conventional seal 50, the cross-sectional height H of the seal 50 can be lowered without deteriorating the muddy water resistance, and the wheel bearing can be made lighter and more compact. For example, on the side closer to the outside of the vehicle. Compared to the integrated seal used, the number of parts increases by the amount of the slinger 51, resulting in an increase in cost.

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a wheel bearing device that secures muddy water resistance of the seal and reduces the cost of the seal.

  In order to achieve the object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and an outer rolling surface of the double row on the outer periphery. An inner member in which a double row inner rolling surface facing the inner member is formed, and a double row of the inner member and the outer member that are accommodated so as to roll freely between the rolling surfaces of the inner member and the outer member. In a wheel bearing device comprising a rolling element and a seal attached to an opening of an annular space formed between the outer member and the inner member, at least one of the seals is the seal A cylindrical fitting portion that is press-fitted into the outer diameter of the inner member via a predetermined shimoshiro, a disc portion that extends radially outward from the fitting portion, and an outer portion that extends in an axial direction from the disc portion A cored bar with a cross-section formed by pressing from a steel plate and vulcanized and bonded to the outer diameter part of the cored bar. And a pair of dust strips extending obliquely outward in the radial direction, and a synthetic rubber seal member having a grease lip extending inclined toward the bearing inward side on the inner diameter side. In addition, the inner peripheral surface of the end portion of the outer member is formed in a curved shape having an arc surface that gradually increases in diameter toward the end surface, and the dust lip and the grease lip are formed on the inner peripheral surface of the end portion through a predetermined shimiro. It is in sliding contact.

  Thus, in the wheel bearing device including the seal mounted in the opening of the annular space formed between the outer member and the inner member, at least one of the seals is the inner member. A cylindrical fitting portion that is press-fitted into the outer diameter via a predetermined shimoshiro, a disk portion that extends radially outward from the fitting portion, and an outer diameter portion that extends in the axial direction from the disk portion. Equipped with a metal core whose cross section is formed into a substantially U shape by pressing from a steel plate, and is integrally joined to the outer diameter portion of this metal core by vulcanization adhesion, and extends inclining radially outward. A pair of dust strips and a synthetic rubber seal member having a grease lip extending inclinedly toward the bearing inner side on the inner diameter side, and the inner peripheral surface of the end portion of the outer member face the end surface. Formed in a curved shape with a circular arc surface that gradually increases in diameter, Since the slip is in sliding contact with the inner peripheral surface of the end portion through a predetermined shishiro, even if the conventional slinger is eliminated, the mud water resistance of the seal is ensured and the number of parts is reduced to reduce the seal. It is possible to provide a wheel bearing device that achieves cost reduction.

  Preferably, as in the invention described in claim 2, the sealing member has a covering portion that protects a surface exposed to the outside of the core metal, and the covering portion is an end of the fitting portion of the core metal. If the part of the covering portion is elastically contacted with the outer diameter of the inner member, the airtightness of the fitting surface between the seal and the inner member can be improved.

  According to a third aspect of the present invention, the disc portion of the core metal of the seal extends radially outward from the bearing inner end of the fitting portion, and the outer diameter portion is If it extends from the disc part to the bearing outer side, and the end face of the outer diameter part and the fitting part is set to be substantially flush, when pressing the seal, both faces can be pressed simultaneously, Deformation during press fitting can be suppressed.

  According to a fourth aspect of the present invention, the disk portion of the core metal of the seal extends radially outward from the bearing inner end of the fitting portion, and the outer diameter portion If the end surface of the fitting portion extends from the disc portion to the bearing outer side and the end surface of the fitting portion projects to the bearing outer side from the end surface of the outer diameter portion, the seal is laminated on the production line or assembly line. In addition, it is possible to prevent the lips of adjacent seals from coming into contact with each other, and the seal lips can be placed without being damaged.

  Further, as in the invention described in claim 5, the disc portion of the core metal of the seal extends radially outward from the bearing outer side end of the fitting portion, and the outer diameter portion is If it extends from the disk part to the bearing inward side, when the seal is press-fitted, the flat disk part can be pressed, and deformation during press-fitting can be suppressed.

  According to a sixth aspect of the present invention, the core metal of the seal further includes a ridge portion that further bends from the outer diameter portion and extends radially outward, and the tip end portion of the ridge portion is the outer portion. If the labyrinth seal is configured to face the inner peripheral surface of the end of the side member through a slight radial gap, the number of parts can be reduced, the cost can be reduced, and the muddy water resistance of the seal can be improved. Can do.

  According to a seventh aspect of the present invention, the seal member is integrally provided with a protrusion that extends radially outward, and the tip of the protrusion is slightly on the inner peripheral surface of the end of the outer member. If the labyrinth seal is configured to face each other through a gap in the radial direction, the number of parts can be reduced and the cost can be reduced, and the muddy water resistance of the seal can be improved.

  Further, as in the invention described in claim 8, if an annular groove is formed on the inner periphery of the end portion of the outer member, and the protrusion is engaged with the annular groove, the seal is resistant to mud water. This can be further improved.

  Further, as in the ninth aspect of the invention, if the ridge portion of the seal member is formed in a spire shape that narrows toward the tip, the rigidity of the root portion of the ridge portion is increased and deformation is caused. It can be suppressed and damage at the time of interference with other parts can be prevented.

  In addition, as in the invention described in claim 10, the protruding portion is formed to be inclined outward in the radial direction, and a tip portion of the protruding portion is formed on the inner peripheral surface of the end portion of the outer member via a slight radial gap. If a labyrinth seal is formed, the muddy water that has entered the seal can be easily drained by centrifugal force, and the muddy water resistance of the seal can be further improved.

  Further, as in the invention described in claim 11, the seal member may have a rubber property value having a compression set of 40% or less at 120 ° C. × 70 hours and a TR10 value of −35 ° C. or less. For example, the strain recovery is good even in a low temperature region, and the desired sealing performance can be maintained.

  The wheel bearing device according to the present invention includes an outer member in which a double row outer rolling surface is integrally formed on an inner periphery, and a double row inner rolling that faces the outer rolling surface of the double row on an outer periphery. An inner member having a surface formed thereon, a double row rolling element housed between the rolling surfaces of the inner member and the outer member via a cage, and the outer member; In a wheel bearing device including a seal mounted in an opening of an annular space formed between the inner member and at least one of the seals, the outer diameter of the inner member is a predetermined value. A cylindrical fitting portion press-fitted through a shimoshiro, a disc portion extending radially outward from the fitting portion, and an outer diameter portion extending axially from the disc portion, The core bar whose cross section is formed in a substantially U shape by pressing and the outer diameter part of this core bar are joined together by vulcanization, and the radial direction And a synthetic rubber seal member having a grease lip extending inclined toward the inner side of the bearing on the inner diameter side thereof, and in the end portion of the outer member. The peripheral surface is formed in a curved shape having an arc surface gradually expanding toward the end surface, and the dust lip and the grease lip are slidably contacted with the inner peripheral surface of the end portion through a predetermined shimiro. Even if such a slinger is abolished, it is possible to provide a wheel bearing device in which the muddy water resistance of the seal is ensured and the number of parts is reduced to reduce the cost of the seal.

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 FIG. It is explanatory drawing which shows the modification of the seal | sticker of FIG. It is a principal part enlarged view which shows the other modification of the seal | sticker of FIG. FIG. 9 is an enlarged view of the main part showing another modification of the seal of FIG. FIG. 9 is an enlarged view of the main part showing another modification of the seal 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 modification of the seal | sticker of FIG. It is a principal part enlarged view which shows the other modification of the seal | sticker of FIG. It is a principal part enlarged view which shows the other modification of the seal | sticker 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 other modification of the seal | sticker 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 longitudinal cross-sectional view which shows the seal | sticker of the conventional wheel bearing apparatus.

  A vehicle body mounting flange to be attached to the knuckle on the outer periphery, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel mounting flange to mount a wheel on one end A hub wheel integrally formed and having an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small-diameter step portion extending in the axial direction from the inner rolling surface, and the hub wheel An inner member comprising an inner ring that is press-fitted into a small-diameter step portion and has an outer race formed with an inner race surface facing the other of the outer row raceways in the double row, and both the inner member and the outer member. For a wheel including a double row rolling element accommodated between the rolling surfaces so as to be freely rollable, and a seal attached to an opening of an annular space formed between the outer member and the inner member. In the bearing device, at least one of the seals has a predetermined outer diameter of the inner ring. A cylindrical fitting portion press-fitted through a shimoshiro, a disc portion extending radially outward from the fitting portion, and an outer diameter portion extending axially from the disc portion, A core bar having a substantially U-shaped cross-section by press working, and a pair of dust strips that are integrally joined to the outer diameter portion of the core bar by vulcanization adhesion and that extend obliquely outward in the radial direction; A grease lip extending inwardly on the inner diameter side of the bearing, and a synthetic rubber sealing member having a covering portion for protecting the surface exposed to the outside of the cored bar. The part is wrapped around and joined to the end of the fitting part of the core metal, and a part of the covering part is elastically contacted with the outer diameter of the inner ring, and the inner peripheral surface of the end of the outer member is It is formed in a curved shape having an arc surface that gradually increases in diameter toward the end surface, and Slip is the sliding contact via a predetermined Interference on the end inner peripheral surface.

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 is an enlarged view of a main part showing a seal part of FIG. 1, and FIG. 3 is a modification of the seal of FIG. FIG. 4 to FIG. 6 are main part enlarged views showing another modification of the seal of FIG. 2, FIG. 7 is a main part enlarged view showing a modification of the seal of FIG. 6, and FIG. FIG. 9 is an enlarged view of a main part showing another modification of the seal of FIG. 5, FIG. 9 is an enlarged view of a main part showing another modification of the seal of FIG. 6, and FIG. 10 shows another modification of the seal of FIG. The principal part enlarged view and FIGS. 11 and 12 are principal part enlarged views showing a modification of the seal of FIG. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  This wheel bearing device is for a drive wheel called the third generation, and is a double row rolling element housed in a freely rollable manner between the inner member 1, outer member 2, and both members 1,2. (Balls) 3 and 3. The inner member 1 includes a hub ring 4 and an inner ring 5 press-fitted into the hub ring 4 through a predetermined shimiro.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A cylindrical small-diameter step portion 4b extending in the axial direction from the surface 4a is formed, and a serration (or spline) 4c 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 inner ring 5 is formed with the other (inner side) inner rolling surface 5a on the outer periphery, and is press-fitted into the small-diameter step portion 4b of the hub ring 4 to constitute a back-to-back type double-row angular ball bearing. The inner ring 5 and the rolling element 3 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching.

  The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to a knuckle (not shown) on the outer periphery, and a double row of inner rows facing the inner rolling surfaces 4a and 5a of the inner member 1 on the inner periphery. The outer rolling surfaces 2a and 2a are integrally formed. Double-row rolling elements 3 and 3 are accommodated between these rolling surfaces and are held by the cages 7 and 7 so as to be freely rollable. Seals 8 and 9 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1, and leakage of grease sealed inside the bearing and rainwater from the outside. And dust are prevented from entering the bearing.

  The outer member 2 is formed 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 2a and 2a have a surface hardness of 58 to 64 HRC by induction hardening. Is subjected to a predetermined curing treatment. In addition, although the wheel bearing apparatus comprised by the double row angular contact ball bearing which used the ball for the rolling element 3 was illustrated here, it is not restricted to this, The double row tapered roller bearing which used the tapered roller for the rolling element 3 It may be configured by. Further, the present invention is not limited to the third generation structure, and may be first to fourth generation structures.

  The hub wheel 4 is made of medium and high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C, and includes an inner rolling surface 4a and an inner portion of a wheel mounting flange 6 that serves as a seal land portion of the outer seal 8. A predetermined hardened layer having a surface hardness in the range of 58 to 64 HRC is formed by induction hardening from the side base portion 6b to the small diameter step portion 4b.

  Here, the seal 8 on the outer side of the seals 8, 9 is joined to the core metal 10 that is press-fitted to the inner periphery of the outer side end portion of the outer member 2 via a predetermined shimoshiro, and the core metal 10. It is constituted by an integrated seal composed of the seal member 11. The metal core 10 is formed in a substantially L-shaped cross section by pressing austenitic stainless steel plate (JIS standard SUS304 type or the like) or cold rolled steel plate (JIS standard SPCC type or the like).

  On the other hand, the seal member 11 is made of synthetic rubber such as NBR (acrylonitrile-butadiene rubber) and is integrally joined to the cored bar 10 by vulcanization adhesion. The seal member 11 is formed to be inclined outward in the radial direction, and has a side lip 11a that is in sliding contact with a side surface on the inner side of the wheel mounting flange 6 with a predetermined axial squeeze, and a base portion 6b that is formed in an arc shape in cross section. The side lip 11b is in sliding contact with a predetermined axial direction and the grease lip 11c is formed so as to be inclined toward the inner side of the bearing.

  The seal 9 on the inner side is an integral type composed of a cored bar 12 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro, and a seal member 13 integrally joined to the cored bar 12 by vulcanization adhesion. It consists of a seal. The core metal 12 is formed into an annular shape as a whole by pressing from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust prevention, and is enlarged in FIG. As shown, a cylindrical fitting portion 12a press-fitted into the inner ring 5, a disc portion 12b extending radially outward from the fitting portion 12a, and a cylindrical shape extending in the axial direction from the disc portion 12b. The outer diameter portion 12c.

  On the other hand, the seal member 13 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a covering portion 13d that protects the exposed surface of the cored bar 12. The covering portion 13d wraps around and is joined to the end of the fitting portion 12a of the cored bar 12. The portion elastically contacts the outer diameter of the inner ring 5 to improve the airtightness of the fitting surface. The end member inner peripheral surface 2c of the outer member 2 is formed in a curved shape having an arc surface that gradually increases in diameter toward the end surface, and the dust strips 13a and 13b are formed on the end inner peripheral surface 2c in a predetermined radial direction. The grease lip 13c is in sliding contact with the inner peripheral surface 2c of the end portion through a shimoshiro in a predetermined axial direction. As a result, it is possible to provide a wheel bearing device in which the sludge water resistance of the seal 9 is ensured even if the conventional slinger is eliminated, and the cost of the seal 9 is reduced by reducing the number of parts.

  In addition to NBR, the material of the seal member 13 includes, for example, HNBR (hydrogenated acrylonitrile-butadiene rubber), EPM, EPDM (ethylene / propylene rubber), etc., which have excellent heat resistance, heat resistance and chemical resistance. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in properties.

  Here, in this embodiment, the end face of the fitting part 12a of the seal 9 and the outer diameter part 12c is set to be substantially flush. Thereby, when pressing the seal | sticker 9, both surfaces can be pressed simultaneously and the deformation | transformation at the time of press injection can be suppressed. The term “substantially equal” as used herein means, for example, a design target value that is substantially free of steps, that is, a step caused by a processing error or the like should be allowed.

  Further, as the seal member 13 of the seal 9, a rubber material having a compression set of 40% or less at 120 ° C. × 70 hours and a TR10 value (elongation rate 50%) of −35 ° C. or less is used. As a result, the strain recovery is good even in the low temperature region, and the desired sealing performance can be maintained. Here, the TR10 value indicates the temperature when the strain applied in advance is recovered by 10%, and the vicinity of this value is empirically used as the low temperature limit value of the rubber material.

  FIG. 3 shows a modification of the seal 9 described above. The seal 14 is basically different from the above-described seal 9 only in a part of the configuration of the cored bar, and other parts having the same functions or functions as those of the above-described embodiments are denoted by the same reference numerals. Detailed description is omitted.

  The seal 14 is constituted by an integral seal composed of a core metal 15 and a seal member 13 integrally joined to the core metal 15 by vulcanization adhesion. The core 15 is formed into an annular shape as a whole by pressing from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, a disc portion 12b extending radially outward from the fitting portion 12a, and an outer diameter portion 15a extending obliquely from the disc portion 12b in the axial direction. .

  Here, in this embodiment, the end surface of the fitting portion 12a of the seal 14 is formed so as to protrude to the inner side from the end surface of the outer diameter portion 15a. Thereby, even if the seal 14 is laminated on the production line or the assembly line, it is possible to prevent the lips of the adjacent seals from coming into contact with each other, and the seal 14 can be placed without being damaged.

  The seal 16 shown in FIG. 4 is basically the same as the seal 9 described above, but the direction of the cored bar 17 is reversed horizontally. The cored bar 17 and a sealing member integrally joined to the cored bar 17 by vulcanization bonding It is comprised by the integrated seal | sticker which consists of 18. The metal core 17 is formed into an annular shape as a whole by press working from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 17a, a disc portion 17b extending radially outward from the fitting portion 17a, and a cylindrical outer diameter portion 17c extending axially from the disc portion 17b. .

  On the other hand, the seal member 18 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a covering portion 18a for protecting the exposed surface from the outer diameter portion 17c of the cored bar 17 to the fitting portion 17a. Thus, as in the above-described embodiment, the number of parts is reduced and the cost is reduced while securing the mud water resistance of the seal 16, and the flat disk portion 17b is pressed when the seal 16 is press-fitted. And deformation during press-fitting can be suppressed.

  The seal 19 shown in FIG. 5 is an integral type comprising a cored bar 20 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro and a seal member 21 integrally joined to the cored bar 20 by vulcanization adhesion. It is composed of a seal. The core 20 is formed into an annular shape as a whole by pressing from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, a disc portion 12b extending radially outward from the fitting portion 12a, a cylindrical outer diameter portion 12c extending axially from the disc portion 12b, and the outer diameter And a ridge portion 20a that is further bent from the portion 12c and extends radially outward.

  On the other hand, the seal member 21 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a covering portion 21a that protects the exposed surface from the outer diameter portion 12c of the cored bar 20 to the fitting portion 12a via the protruding portion 20a.

  Here, in this embodiment, the protruding portion 20a of the cored bar 20 faces the end inner peripheral surface 2c of the outer member 2 via a slight radial gap to constitute the labyrinth seal 22. Thereby, while reducing a number of parts and achieving cost reduction, the muddy water resistance of the seal | sticker 19 can be improved.

  The seal 23 shown in FIG. 6 is an integral type comprising a cored bar 12 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro, and a seal member 24 integrally joined to the cored bar 12 by vulcanization adhesion. It is composed of a seal.

  The seal member 24 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side, and A covering portion 24a that protects the exposed surface from the outer diameter portion 12c of the core metal 12 to the fitting portion 12a, and a protrusion 25 that extends radially outward are integrally formed on the outer diameter portion 12c of the core metal 12. Has been.

  Here, in the present embodiment, the protrusion 25 of the seal member 24 faces the end inner peripheral surface 2c of the outer member 2 via a slight radial gap to constitute the labyrinth seal 22. Thereby, like the embodiment described above, the number of parts can be reduced to reduce the cost, and the muddy water resistance of the seal 23 can be improved.

  The seal 26 shown in FIG. 7 includes a cored bar 12 ′ press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro, and a seal member 27 integrally joined to the cored bar 12 ′ by vulcanization adhesion. It is composed of an integral seal. The core metal 12 'is formed into an annular shape as a whole by press working from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, and a disc portion 12b extending radially outward from the fitting portion 12a.

  On the other hand, the seal member 27 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. , And a covering portion 27a that protects the exposed surface from the disc portion 12b to the fitting portion 12a of the cored bar 12 ', and a ridge portion 25 that extends radially outwardly on the outer side of the dust lip 13a. Has been.

  Here, in the present embodiment, the protrusion 25 of the seal member 27 faces the end inner peripheral surface 2c of the outer member 2 via a slight radial gap to constitute the labyrinth seal 22. Thereby, like the embodiment described above, the number of parts can be reduced to reduce the cost, and the muddy water resistance of the seal 26 can be improved.

  The seal 28 shown in FIG. 8 is composed of a cored bar 20 ′ press-fitted into the outer diameter of the inner ring 5 via a predetermined scissors, and a seal member 21 ′ joined integrally to the cored bar 20 ′ by vulcanization adhesion. It is comprised by the integrated seal which becomes. The metal core 20 ′ is formed into an annular shape as a whole by press working from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, a disc portion 12b extending radially outward from the fitting portion 12a, and a cylindrical outer diameter portion 12c extending inclined from the disc portion 12b in the axial direction, Further, a ridge portion 20a ′ that is bent from the outer diameter portion 12c and extends radially outward is provided.

  On the other hand, the seal member 21 'is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip extending inclined toward the bearing inward side on the inner diameter side. 13c, and a covering portion 21a 'that protects the exposed surface from the outer diameter portion 12c of the cored bar 20' to the fitting portion 12a through the protrusion 20a '.

  Here, in this embodiment, the protruding portion 20 a ′ of the seal member 28 is engaged with an annular step portion 30 formed on the inner periphery of the end portion of the outer member 29, thereby configuring the labyrinth seal 22. As a result, as in the above-described embodiment, the number of parts can be reduced to reduce costs, and the muddy water resistance of the seal 28 can be further improved.

  The seal 31 shown in FIG. 9 is composed of a core metal 12 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro, and a seal member 24 ′ integrally joined to the core metal 12 by vulcanization adhesion. It consists of a body-shaped seal.

  The seal member 24 ′ is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending inclined outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a covering portion 24a ′ that protects the exposed surface from the outer diameter portion 12c of the core metal 12 to the fitting portion 12a, and a protrusion 25 that extends radially outward is integrated with the outer diameter portion 12c of the core metal 12. Is formed.

  Here, in the present embodiment, the protrusion 25 of the seal member 31 engages with the annular groove 32 formed on the inner periphery of the end of the outer member 29 ′ to configure the labyrinth seal 33. As a result, as in the above-described embodiment, the number of parts can be reduced to reduce costs, and the muddy water resistance of the seal 31 can be further improved.

  The seal 34 shown in FIG. 10 is an integral type comprising a core metal 12 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro and a seal member 35 integrally joined to the core metal 12 by vulcanization adhesion. It is composed of a seal.

  The seal member 35 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side, and A covering portion 24b that protects the exposed surface from the outer diameter portion 12c of the core metal 12 to the fitting portion 12a, and a protrusion 25 'that extends radially outward is integrally formed on the outer diameter portion 12c of the core metal 12. Is formed.

  Here, in this embodiment, the protrusion 25 'of the seal member 35 is formed in a steeple shape that narrows toward the tip, and faces the end inner peripheral surface 2c of the outer member 2 through a slight radial gap. The labyrinth seal 22 is configured. As a result, the mud water resistance of the seal 35 can be improved, the rigidity of the root portion of the protruding portion 25 ′ can be increased and deformation can be suppressed, and damage at the time of interference with other parts can be prevented.

  The seal 36 shown in FIG. 11 is an integral type comprising a core metal 37 press-fitted into the outer diameter of the inner ring 5 via a predetermined shimiro, and a seal member 38 integrally joined to the core metal 37 by vulcanization adhesion. It is composed of a seal. The core metal 37 is formed into an annular shape as a whole by pressing from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, a disc portion 12b extending radially outward from the fitting portion 12a, and a tapered outer diameter portion 37a extending obliquely from the disc portion 12b in the radial direction. I have.

  On the other hand, the seal member 38 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a covering portion 38a for protecting the exposed surface from the outer diameter portion 37a of the cored bar 37 to the fitting portion 12a.

  Here, in the present embodiment, the outer diameter portion 37 a of the core metal 37 faces the end inner peripheral surface 2 c of the outer member 2 via a slight radial gap to constitute the labyrinth seal 22. Thus, by forming the outer diameter portion 37a of the core metal 37 in a tapered shape, muddy water or the like that has entered the seal 36 can be easily drained by centrifugal force, and the muddy water resistance of the seal 36 is further improved. Can be improved.

  The seal 39 shown in FIG. 12 is an integral type comprising a cored bar 15 press-fitted into the outer diameter of the inner ring 5 via a predetermined scissors, and a seal member 40 integrally joined to the cored bar 15 by vulcanization adhesion. It is composed of a seal. The core 15 is formed into an annular shape as a whole by pressing from an austenitic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the inner ring 5. A cylindrical fitting portion 12a, a disc portion 12b extending radially outward from the fitting portion 12a, and a tapered outer diameter portion 15a extending obliquely from the disc portion 12b in the radial direction. I have.

  On the other hand, the seal member 40 is made of a synthetic rubber such as NBR, and has a pair of dust strips 13a and 13b extending obliquely outward in the radial direction, and a grease lip 13c extending inclined toward the bearing inward side on the inner diameter side. And a protrusion 40a extending obliquely outward in the radial direction on the inner side of the dust lip 13a, and a covering portion 40b for protecting the exposed surface from the outer diameter portion 15a of the metal core 15 to the fitting portion 12a. ing.

  Here, in the present embodiment, the protrusion 40 a of the seal member 40 faces the end inner peripheral surface 2 c of the outer member 2 via a slight radial gap to constitute the labyrinth seal 22. Thereby, like the above-described embodiment, the muddy water or the like that has entered the seal 39 can be easily drained by centrifugal force, and the mud water resistance of the seal 39 can be further improved.

  FIG. 13 is a longitudinal sectional view showing a second embodiment of the wheel bearing device according to the present invention. Note that this embodiment is basically different from the above-described embodiment only in the bearing structure, and the same parts and parts having the same functions or parts having the same functions are denoted by the same reference numerals and detailed description thereof is omitted. .

  The wheel bearing 41 is referred to as a first generation, and is fitted into a knuckle (not shown), and an outer member 42 in which double row outer rolling surfaces 42a and 42a are integrally formed on the inner periphery, and a hub wheel (not shown). A pair of inner rings 5 and 5 that are externally fitted to each other, and double-row rolling elements 3 and 3 that are accommodated so as to be freely rollable between the two members.

  The outer member 42 is made of high carbon chrome steel such as SUJ2, and is hardened in the range of 58 to 64 HRC up to the core part by quenching. Seals 9 and 9 are attached to the opening of the annular space formed between the outer member 42 and the pair of inner rings 5 and 5, and leakage of grease sealed inside the bearing to the outside Prevents rainwater and dust from entering the bearing. In the present embodiment, like the above-described embodiment, by adopting such a seal 9, it is possible to secure the mud water resistance of the seal 9 and reduce the number of parts of the seal 9 to reduce the cost.

  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 sealed type first to fourth generation wheel bearing device having a seal regardless of whether it is for driving wheels or driven wheels.

DESCRIPTION OF SYMBOLS 1 Inner member 2, 29, 29 ', 42 Outer member 2a, 42a Outer rolling surface 2b Car body mounting flange 2c End inner peripheral surface 3 Rolling body 4 Hub wheel 4a, 5a Inner rolling surface 4b Small diameter step 4c Serration 5 Inner ring 6 Wheel mounting flange 6a Hub bolt 6b Inner side base 7 of wheel mounting flange Cage 8, 9, 14, 16, 19, 21, 23, 26, 28, 31, 34, 36, 39 Seals 10, 12, 15, 17, 20, 12 ', 20', 37 Core metal 11, 13, 18, 21, 24, 27, 21 ', 24', 35, 38, 40 Seal member 11a, 11b Side lip 11c, 13c Grease lip 12a, 17a Fitting part 12b, 17b Disc part 12c, 15a, 17c, 37a Outer diameter part 13a, 13b Dustrip 13d, 18a, 21a, 21a ', 24a, 24a' , 24b, 27a, 38a, 40b Cover portions 20a, 20a ′, 25, 25 ′, 40a Projection portions 22, 33 Labyrinth seal 30 Step portion 32 Annular groove 41 Wheel bearing 50 Seal 51 Slinger 51a Cylindrical portion 51b Standing plate portion 52 Seal plate 53 Core metal 54 Seal member 54a Side lip 54b on the outer diameter side Side lip 54c on the inner diameter side Grease lip 55 Magnetic encoder d Distance between side lips

Claims (11)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
An inner member in which a double row inner rolling surface facing the outer row rolling surface of the double row is formed on the outer periphery;
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 a wheel bearing device comprising a seal mounted in an opening of an annular space formed between the outer member and the inner member,
A cylindrical fitting portion in which at least one of the seals is press-fitted into the outer diameter of the inner member via a predetermined shimoshiro, and a disk portion extending radially outward from the fitting portion An outer diameter portion extending in the axial direction from the disk portion, and a core metal having a substantially U-shaped cross section formed by pressing from a steel plate, and vulcanized and bonded to the outer diameter portion of the core metal And a pair of dust strips extending obliquely outward in the radial direction, and a synthetic rubber seal member having a grease lip extending inclined toward the bearing inward side on the inner diameter side. In addition, the inner peripheral surface of the end portion of the outer member is formed in a curved shape having an arc surface that gradually increases in diameter toward the end surface, and the dust lip and the grease lip are formed on the inner peripheral surface of the end portion through a predetermined shimiro. A wheel bearing device characterized by being in sliding contact.   The sealing member has a covering portion that protects the surface exposed to the outside of the core metal, and the covering portion wraps around and joins the end portion of the fitting portion of the core metal. The wheel bearing device according to claim 1, wherein the portion is in elastic contact with the outer diameter of the inner member.   A disc portion of the core metal of the seal extends radially outward from an end portion on the bearing inner side of the fitting portion, and the outer diameter portion extends outward from the disc portion to the bearing outer side. The wheel bearing device according to claim 1 or 2, wherein an end surface of the diameter portion and the fitting portion is set substantially flush.   A disc portion of the core metal of the seal extends radially outward from an end portion on the bearing inner side of the fitting portion, and the outer diameter portion extends outward from the disc portion to the bearing outer side. The wheel bearing device according to claim 1 or 2, wherein an end surface of the fitting portion is formed so as to protrude outward from the end surface of the diameter portion.   The disc portion of the core metal of the seal extends radially outward from the end portion of the fitting portion on the outer side of the bearing, and the outer diameter portion extends from the disc portion to the inner side of the bearing. Item 3. A wheel bearing device according to Item 1 or 2.   The seal core includes a protrusion that further bends from the outer diameter portion and extends outward in the radial direction, and the tip of the protrusion has a slight radial gap on the inner peripheral surface of the end of the outer member. The wheel bearing device according to any one of claims 1 to 5, wherein a labyrinth seal is configured to face each other.   The seal member is integrally provided with a protrusion extending radially outward, and the tip of the protrusion is opposed to the inner peripheral surface of the end of the outer member via a slight radial gap, thereby providing a labyrinth seal. The wheel bearing device according to any one of claims 1 to 5, wherein the wheel bearing device is configured.   The wheel bearing device according to claim 6 or 7, wherein an annular groove is formed in an inner periphery of the end portion of the outer member, and the protrusion is engaged with the annular groove.   The wheel bearing device according to any one of claims 6 to 8, wherein a protruding portion of the seal member is formed in a spire shape that narrows toward a tip.   The ridge portion is formed so as to be inclined radially outward, and a tip portion thereof is opposed to an inner peripheral surface of an end portion of the outer member via a slight radial gap to constitute a labyrinth seal. The wheel bearing apparatus in any one of 6 thru | or 9.   2. The wheel bearing device according to claim 1, wherein the seal member has a compression set of a rubber property value of 40% or less at 120 ° C. × 70 hours and a TR10 value of −35 ° C. or less.

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