JP2019163848A - Wheel bearing device - Google Patents

Abstract

To provide a wheel bearing device which can reduce rotation torque while maintaining high sealing performance by a seal member, and is easy in the attachment of the seal member.SOLUTION: In a wheel bearing device 1 in which one side lip 62a is formed at an elastic member 62, the side lip 62a extends to a rotating shaft A of an inner member 3 at a prescribed angle α, and a tip edge of the side lip 62a is in contact with a slide contact face (a flat end face 3, or a circular arc face 3j) of a hub ring 31, one labyrinth slip 62d is formed at the elastic member 62, the labyrinth slip 62d extends at an angle β smaller than the prescribed angle α at the outside of a radial direction rather than the side lip 62a, a tip edge of the labyrinth slip 62d opposes the slide contact face (flat end face 3i) of the hub ring 31, and a push-in face 62e which is not superimposed with the labyrinth slip 62d in an axial direction and vertical to the axial direction is formed outside the radial direction of the labyrinth slip 62d of the elastic member 62.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a wheel bearing device.

  2. Description of the Related Art Conventionally, a wheel bearing device that supports a wheel rotatably is known (see Patent Document 1). In such a wheel bearing device, the outer member is fixed to the vehicle body. An inner member is disposed inside the outer member, and a plurality of rolling elements are interposed between the raceway surfaces of the outer member and the inner member. In this way, the wheel bearing device constitutes a rolling bearing structure, and the wheel attached to the inner member is rotatable.

  By the way, in such a wheel bearing device, an annular space is formed by an outer member and an inner member. If foreign matter (such as muddy water or dust) enters the annular space, the raceway surface, rolling elements, etc. will be damaged and the bearing life will be shortened. In addition, even if the grease sealed in the annular space leaks, the raceway surface, rolling elements, etc. are damaged and the bearing life is shortened. Therefore, the wheel bearing device is provided with a seal member in order to prevent intrusion of foreign substances and to prevent leakage of grease.

  The wheel bearing device described in Patent Literature 1 includes a pair of seal members that closes both side opening ends of the annular space. Here, paying attention to the sealing member that closes the outer opening end, the sealing member is composed of a core metal fitted into the outer member and an elastic member fixed to the core metal. The elastic member is formed with two side lips, and the respective leading edges are in contact with the sliding contact surface of the hub wheel. However, the structure in which two side lips are formed and the respective leading edges contact the sliding contact surface of the hub wheel has a problem in that the rotational torque increases.

  In addition, the wheel bearing device is completed through a process of mounting a seal member on the outer opening end of the annular space (hereinafter referred to as “mounting process”). In the mounting process, it is necessary to apply a jig to the vicinity of the fitting portion of the metal core constituting the seal member and push it from the outer side to the inner side. However, in the case of a seal member in which two side lips are formed on an elastic member as in the wheel bearing device described in Patent Document 1, the side lip on the outer side in the radial direction is particularly disturbing. There was a problem that it would be difficult to push.

  From the above, there has been a demand for a wheel bearing device that can realize a reduction in rotational torque while maintaining high sealing performance by the sealing member, and that is easy to mount the sealing member.

JP 2011-088513 A

  Provided is a wheel bearing device in which a reduction in rotational torque can be realized while maintaining high sealing performance by a sealing member, and furthermore, the mounting performance of the sealing member is easy.

The first invention is
An outer member having a double-row outer raceway surface formed on the inner periphery;
An inner member having a hub ring formed with a small-diameter stepped portion and an inner ring that is externally fitted to the small-diameter stepped portion, and a double row outer raceway surface formed on the outer periphery;
A plurality of rolling elements interposed between the raceway surfaces of the outer member and the inner member;
A seal member mounted on an outer opening end of an annular space formed between the outer member and the inner member;
The seal member is composed of a core metal fitted into the outer member and an elastic member fixed to the core metal;
One side lip is formed on the elastic member, the side lip extends at a predetermined angle with respect to the rotation axis of the inner member, and the tip edge of the side lip contacts the sliding contact surface of the hub wheel. In the wheel bearing device,
One labyrin slip is formed on the elastic member, the labyrin slip extends radially outside the side lip at an angle smaller than the predetermined angle, and the leading edge of the labyrin slip is in sliding contact with the hub wheel. Facing the surface through a labyrinth gap,
Of the elastic member, a pressing surface that is not overlapped in the axial direction and perpendicular to the axial direction is formed on the radially outer side of the labyrin slip.

2nd invention is the wheel bearing apparatus which concerns on 1st invention,
The outer side end surface of the outer member and the sliding contact surface of the hub wheel are opposed to each other,
The distance from the outer side end surface of the outer member to the sliding contact surface of the hub wheel is shorter or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. .

3rd invention is the bearing apparatus for wheels which concerns on 1st invention,
The sliding contact surface is provided at a stepped portion protruding to the inner side of the hub wheel;
An outer side end portion of the outer member is extended to a radially outer side of the stepped portion.

4th invention is the wheel bearing apparatus which concerns on 3rd invention,
An enlarged diameter portion is formed on the inner edge of the outer member on the outer side end,
The distance from the diameter difference surface in the enlarged diameter portion to the sliding contact surface of the hub wheel is shorter or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. .

5th invention is the wheel bearing apparatus which concerns on 3rd invention,
An enlarged diameter portion is formed on the inner edge of the outer member on the outer side end,
The distance from the inner peripheral surface of the enlarged diameter portion to the outer peripheral surface of the step portion of the hub wheel is shorter than or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. It is.

  As effects of the present invention, the following effects can be obtained.

  According to the wheel bearing device of the first aspect of the invention, one side lip contacts the sliding contact surface of the hub wheel to prevent entry of foreign matter, and one labyrin slip receives foreign matter directed to the side lip. And fulfill the function to eliminate. Therefore, it is possible to reduce the rotational torque while maintaining high sealing performance by the sealing member. Moreover, since the pushing surface is formed in the vicinity of the fitting part of the core metal which comprises a sealing member, a jig can be applied to this pushing surface. Therefore, the mounting property of the seal member becomes easy.

  According to the wheel bearing device of the second invention, the cross-sectional area of the passage which is the gap between the outer member and the hub wheel is reduced, so that the foreign matter (such as muddy water and dust) reaching the labyrin slip and the side lip is reduced. be able to. Therefore, high sealing performance by the sealing member can be maintained.

  According to the wheel bearing device according to the third aspect of the present invention, the passage that is the gap between the outer member and the hub wheel becomes complicated, so that the foreign matter (such as muddy water and dust) that reaches the labyrin slip and the side lip can be reduced. it can. Therefore, high sealing performance by the sealing member can be maintained.

  According to the wheel bearing device of the fourth invention, the passage that is the gap between the outer member and the hub wheel is complicated, and the cross-sectional area of the passage is reduced, so that the foreign matter that reaches the labyrinth slip and the side lip (Muddy water, dust, etc.) can be reduced. Therefore, high sealing performance by the sealing member can be maintained.

  According to the wheel bearing device of the fifth invention, the passage that is the gap between the outer member and the hub wheel is complicated, and the cross-sectional area of the passage is reduced, so that the foreign matter that reaches the labyrinth slip and the side lip (Muddy water, dust, etc.) can be reduced. Therefore, high sealing performance by the sealing member can be maintained.

The figure which shows the bearing apparatus for wheels. The figure which shows the structure of the bearing apparatus for wheels. The figure which shows the partial structure of the wheel bearing apparatus. The figure which shows the partial structure of the wheel bearing apparatus. The figure which shows the sealing member of the wheel bearing apparatus which concerns on 1st embodiment, and its surrounding structure. The figure which shows the sealing member of the wheel bearing apparatus which concerns on 2nd embodiment, and its surrounding structure. The figure which shows the sealing member of the wheel bearing apparatus which concerns on 3rd embodiment, and its surrounding structure. The figure which shows the sealing member of the wheel bearing apparatus which concerns on 4th embodiment, and its surrounding structure. The figure which shows the condition which press-fits the sealing member to an outward member.

  First, the wheel bearing device 1 according to the present invention will be described. FIG. 1 is a view showing a wheel bearing device 1. FIG. 2 is a view showing the structure of the wheel bearing device 1. 3 and 4 are diagrams showing a partial structure of the wheel bearing device 1. FIG.

  The wheel bearing device 1 supports a wheel rotatably. The wheel bearing device 1 includes an outer member 2, an inner member 3, and a rolling member 4. In this specification, the “inner side” represents the vehicle body side of the wheel bearing device 1 when attached to the vehicle body, and the “outer side” represents the wheel bearing device 1 attached to the vehicle body. Represents the wheel side. The “radially outer side” represents a direction away from the rotation axis A of the inner member 3, and the “radially inner side” represents a direction approaching the rotation axis A of the inner member 3. Further, the “axial direction” represents a direction along the rotation axis A of the inner member 3.

  The outer member 2 constitutes the outer ring portion of the rolling bearing structure. A fitting surface 2 a is formed on the inner periphery of the outer member 2 on the inner side end. A fitting surface 2b is formed on the inner periphery of the outer member 2 at the outer side end. Furthermore, two outer raceway surfaces 2c and 2d are formed on the inner periphery of the outer member 2 in the central portion in the axial direction. In addition, the outer member 2 is formed with a vehicle body mounting flange 2e extending outward in the radial direction. The vehicle body mounting flange 2e is provided with a plurality of bolt holes 2f.

  The inner member 3 constitutes an inner ring portion of the rolling bearing structure. The inner member 3 includes a hub ring 31 and an inner ring 32.

  The hub wheel 31 is inserted inside the outer member 2. A small-diameter step portion 3 a is formed on the outer periphery of the inner end portion of the hub wheel 31 up to the center in the axial direction. The small-diameter step portion 3a indicates a portion where the outer diameter of the hub wheel 31 is reduced, and the outer peripheral surface thereof has a cylindrical shape centered on the rotation axis A. Further, the hub wheel 31 is formed with a spline hole 3b penetrating from the inner side end to the outer side end. Further, an inner raceway surface 3d is formed on the outer periphery of the hub wheel 31 in the center portion in the axial direction. The inner raceway surface 3d faces the outer raceway surface 2d described above in a state where the hub wheel 31 is inserted inside the outer member 2. In addition, the hub wheel 31 is formed with a wheel mounting flange 3e that extends radially outward. The wheel mounting flange 3e is provided with a plurality of bolt holes 3f around the rotation axis A, and a hub bolt 33 is inserted into each bolt hole 3f.

  The inner ring 32 is fitted on the small diameter step 3 a of the hub ring 31. A fitting surface 3g is formed on the outer periphery of the inner ring 32 at the inner side end. An inner raceway surface 3c is formed on the outer periphery adjacent to the fitting surface 3g. The inner ring 32 is fitted on the small diameter step portion 3 a of the hub ring 31, thereby forming an inner raceway surface 3 c on the outer periphery of the hub ring 31. The inner raceway surface 3c faces the outer raceway surface 2c described above in a state where the inner ring 32 integrated with the hub ring 31 is inserted inside the outer member 2.

  The rolling member 4 constitutes a rolling part of the rolling bearing structure. The inner side rolling member 4 includes a plurality of rolling elements 41 and one retainer 42. Similarly, the outer side rolling member 4 is also composed of a plurality of rolling elements 41 and one cage 42.

  Each of the rolling elements 41 is arranged in a circular shape at equal intervals by a cage 42. The rolling element 41 constituting the inner side rolling member 4 is movably interposed between the outer raceway surface 2c of the outer member 2 and the inner raceway surface 3c of the inner member 3 (inner ring 32). It is disguised. Further, the rolling element 41 constituting the outer side rolling member 4 is freely rollable between the outer raceway surface 2d of the outer member 2 and the inner raceway surface 3d of the inner member 3 (hub wheel 31). It is intervened.

  The cage 42 is an annular body in which pockets for accommodating the rolling elements 41 are formed at equal intervals. The retainer 42 has a spherical wall extending between the rolling elements 41 and 41 adjacent to each other, and holds the rolling elements 41 so as to be sandwiched between the two spherical walls. For this reason, the holder | retainer 42 restrict | limits the deviation (shift | offset | difference) of the circumferential direction of each rolling element 41. FIG. Therefore, it is possible to prevent the adjacent rolling elements 41 and the rolling elements 41 from colliding with each other and the rolling elements 41 from rattling.

  In addition, the wheel bearing device 1 includes a pair of seal members 5 and 6 in order to seal the annular space S formed between the outer member 2 and the inner member 3 (hub wheel 31 and inner ring 32). I have. Hereinafter, the seal member 5 attached to the inner side opening end of the annular space S is referred to as “inner side seal member 5”, and the seal member 6 attached to the outer side opening end of the annular space S is referred to as “outer side seal member 6”. ". The inner side seal member 5 has various specifications and is not limited to the specifications disclosed in this specification.

  The inner side seal member 5 includes a slinger 51 and a seal ring 52. The slinger 51 has a cylindrical fitting part 51a and a disk-like side plate part 51b extending radially outward. And the fitting part 51a is externally fitted by the fitting surface 3g of the inner member 3 (inner ring 32). On the other hand, the seal ring 52 is obtained by fixing an elastic member 54 to a cored bar 53. The cored bar 53 has a cylindrical fitting part 53a and a disk-shaped side plate part 53b extending radially inward. Then, the fitting portion 53 a is fitted into the fitting surface 2 a of the outer member 2. The elastic member 54 is formed with side lips 54a and 54b, and the tip edges of the elastic members 54 are in contact with the side plate portions 51b of the slinger 51 facing each other. Furthermore, a grease lip 54c is formed on the elastic member 54, and the tip edge thereof is in contact with or close to the fitting portion 51a of the slinger 51 facing the elastic member 54.

  The outer seal member 6 is obtained by fixing an elastic member 62 to a cored bar 61. The cored bar 61 includes a cylindrical fitting part 61a fitted inside the fitting surface 2b of the outer member 2, and a disk-shaped side plate part 61b extending radially inward from the outer side end of the fitting part 61a. Have. A side lip 62 a is formed on the elastic member 62, and a tip edge thereof is in contact with the flat end surface 3 i or the arc surface 3 j of the step portion 3 h formed on the hub wheel 31. Further, the elastic member 62 is formed with an intermediate lip 62b radially inward of the side lip 62a, and a tip edge thereof is in contact with the arc surface 3j. Further, the elastic member 62 is formed with a grease lip 62c radially inward from the intermediate lip 62b, and the tip edge thereof is in contact with or close to the shaft circumferential surface 3k. In the present specification, the flat end surface 3i, the circular arc surface 3j, and the shaft circumferential surface 3k are defined as “sliding contact surfaces”.

  Here, the stepped portion 3h formed on the hub wheel 31 will be described in detail. The stepped portion 3h indicates a portion projecting toward the inner side at the base end portion of the wheel mounting flange 3e formed on the hub wheel 31. The flat end surface 3i of the stepped portion 3h is a plane perpendicular to the rotation axis A of the inner member 3, and an arc surface 3j is formed on a part of the inner side in the radial direction so that the flat end surface 3i and the shaft The peripheral surface 3k is smoothly connected. The outer peripheral surface 3m of the stepped portion 3h is inclined with a predetermined curvature, and is smoothly connected from the outer edge of the flat end surface 3i to the seat surface 3n of the hub bolt 33.

  Next, features of the wheel bearing device 1 according to the first embodiment and effects thereof will be described. FIG. 5 is a view showing the outer seal member 6 and the surrounding structure of the wheel bearing device 1 according to the first embodiment.

  The elastic member 62 is formed with one side lip 62a. The side lip 62a extends radially outward with respect to the rotational axis A of the inner member 3 at a predetermined angle (angle α), and a tip edge of the side lip 62a is formed on a stepped portion 3h formed on the hub wheel 31. It is in contact with the flat end surface 3i (or arc surface 3j). The side lip 62a extends so as to be spaced outward in the radial direction toward the outer side. For this reason, the side lip 62a increases the tightening force in the direction from the outside toward the annular space S, and thus functions to prevent foreign matters (such as muddy water and dust) from entering the annular space S.

  In addition, one labyrin slip 62d is formed on the elastic member 62 on the radially outer side than the side lip 62a. The labyrinth slip 62d extends radially outward with respect to the rotational axis A of the inner member 3 at a predetermined angle (angle β), and the leading edge of the labyrinth slip 62d is close to the flat end surface 3i of the step portion 3h. Yes. Note that the labyrinth slip 62d extends so as to be spaced outward in the radial direction toward the outer side. Therefore, the labyrinth slip 62d can receive foreign matters (such as muddy water and sand dust) heading from the outside toward the side lip 62a and send them to the valley on the inner side. Thereafter, the foreign matter (such as muddy water and dust) is guided in the circumferential direction along the valley of the labyrinth slip 62d and falls as it is. Further, the angle β of the labyrinth slip 62d is smaller than the angle α of the side lip 62a. Therefore, the leading edge of the labyrinth slip 62d is also close to the leading edge of the side lip 62a. This is because foreign matters (such as muddy water and sand dust) that have passed around the leading edge of the labyrin slip 62d are received together with the side lip 62a and sent to the valley on the inner side.

  In addition, a pressing surface 62e is formed on the elastic member 62 on the radially outer side of the labyrin slip 62d. The pushing surface 62e is formed at a position where the labyrin slip 62d does not overlap in the axial direction. In other words, the pushing surface 62e is formed at a position where the labyrin slip 62d does not overlap when viewed in the axial direction (the direction along the rotation axis A of the inner member 3). The pushing surface 62e is perpendicular to the axial direction (the direction along the rotation axis A of the inner member 3). For this reason, in the mounting process, the jig J can be applied to the pushing surface 62e and pushed from the outer side to the inner side (see FIG. 9).

  As described above, in the wheel bearing device 1 according to the first embodiment, one labyrin slip 62d is formed on the elastic member 62, and the labyrin slip 62d is radially outside the side lip 62a and smaller than the predetermined angle α. The tip edge of the labyrin slip 62d is opposed to the sliding contact surface (flat end surface 3i) of the hub wheel 31 via a labyrinth gap. A pressing surface 62e perpendicular to the axial direction is formed on the radially outer side of the labyrin slip 62d in the elastic member 62 so that the labyrin slip 62d does not overlap in the axial direction. According to such a wheel bearing device 1, one side lip 62 a contacts the sliding contact surface (the flat end surface 3 i or the arc surface 3 j) of the hub wheel 31 to prevent foreign matter from entering, and one labyrin slip 62 d Fulfills the function of catching and removing foreign matter directed to the side lip 62a. Accordingly, it is possible to reduce the rotational torque while maintaining high sealing performance by the outer side seal member 6. Moreover, since the pushing surface 62e is formed in the vicinity of the fitting part 61a of the metal core 61 which comprises the outer side seal member 6, the jig J can be applied to this pushing surface 62e. Therefore, the outer side seal member 6 can be easily mounted.

  Next, characteristic points and effects of the wheel bearing device 1 according to the second embodiment will be described. FIG. 6 is a view showing the outer seal member 6 and the surrounding structure of the wheel bearing device 1 according to the second embodiment. Here, it demonstrates paying attention mainly to the difference with the wheel bearing apparatus 1 which concerns on 1st embodiment.

  In the wheel bearing device 1 according to the present embodiment, the outer side end surface 2e of the outer member 2 and the flat end surface 3i of the stepped portion 3h formed on the hub wheel 31 face each other. In other words, the outer side end surface 2e of the outer member 2 and the sliding contact surface (flat end surface 3i) of the hub wheel 31 face each other.

  In addition, when the distance from the outer end surface 2e of the outer member 2 to the sliding contact surface (flat end surface 3i) of the hub wheel 31 is “B”, the distance B is from the leading edge of the labyrin slip 62d to the hub wheel. It is shorter or the same as the distance to the sliding contact surface 31 (flat end surface 3i). In the present specification, “same” means that a microscopic difference is included in “same”. This is because it is severe to point out a microscopic difference in the position of the leading edge of the labyrin slip 62d which is a part of the elastic member 62.

  Thus, in the wheel bearing device 1 according to the second embodiment, the outer side end surface 2e of the outer member 2 and the sliding contact surface (flat end surface 3i) of the hub wheel 31 face each other. The distance B from the outer end surface 2e of the outer member 2 to the sliding contact surface (flat end surface 3i) of the hub wheel 31 is from the leading edge of the labyrin slip 62d to the sliding contact surface (flat end surface 3i) of the hub wheel 31. It is shorter than or equal to the distance. According to such a wheel bearing device 1, the cross-sectional area of the passage that is the gap between the outer member 2 and the hub wheel 31 is reduced, so that foreign matters (such as muddy water and dust) that reach the labyrinth slip 62 d and the side lip 62 a are reduced. be able to. Therefore, high sealing performance by the outer side seal member 6 can be maintained.

  Next, characteristic points and effects of the wheel bearing device 1 according to the third embodiment will be described. FIG. 7 is a view showing the outer seal member 6 and the surrounding structure of the wheel bearing device 1 according to the third embodiment. Here, the description will be given mainly focusing on differences from the wheel bearing device 1 according to the first embodiment.

  In the wheel bearing device 1 according to the present embodiment, the sliding contact surface (flat end surface 3 i) is provided in the stepped portion 3 h that protrudes toward the inner side of the hub wheel 31. That is, a stepped portion 3h protruding toward the inner side is formed at the base end portion of the wheel mounting flange 3e formed on the hub wheel 31, and the sliding contact surface (flat end surface 3i) is formed by grinding the stepped portion 3h. Provided.

  In addition, the outer side end portion 2f of the outer member 2 extends to the radially outer side of the step portion 3h. For this reason, the outer side end portion 2 f of the outer member 2 partially covers the stepped portion 3 h of the hub wheel 31. By doing so, the passage which is the gap between the outer member 2 and the hub wheel 31 is at least bent and complicated. At the same time, the open end of the passage, which is the gap between the outer member 2 and the hub wheel 31, is directed not in the radial direction but in the axial direction.

  Thus, the wheel bearing device 1 according to the third embodiment is provided in the stepped portion 3h in which the sliding contact surface (flat end surface 3i) of the hub wheel 31 protrudes toward the inner side. And the outer side edge part 2f of the outer member 2 is extended to the radial direction outer side of the level | step-difference part 3h. According to such a wheel bearing device 1, the passage that is the gap between the outer member 2 and the hub wheel 31 becomes complicated, and therefore foreign substances (such as muddy water and dust) that reach the labyrinth slip 62 d and the side lip 62 a can be reduced. it can. Therefore, high sealing performance by the outer side seal member 6 can be maintained.

  In addition, other characteristic points and effects of the wheel bearing device 1 according to the third embodiment will be described.

  In the wheel bearing device 1 according to the present embodiment, an enlarged diameter portion 2g is formed at an inner edge portion of the outer side end portion 2f of the outer member 2. And it has the structure where the outer edge part of the level | step-difference part 3h was settled in this enlarged diameter part 2g.

  In addition, when the distance from the diameter difference surface 2i in the enlarged diameter portion 2g of the outer member 2 to the sliding contact surface (flat end surface 3i) of the hub wheel 31 is “C”, the distance C is equal to the labyrin slip 62d. The distance is shorter or the same as the distance from the front end edge to the sliding contact surface (flat end surface 3i) of the hub wheel 31. Here, “same” means that the same microscopic difference is included in “same”.

  Thus, in the wheel bearing device 1 according to the third embodiment, the enlarged-diameter portion 2g is formed at the inner edge portion of the outer side end portion 2f of the outer member 2. The distance C from the diameter difference surface 2i in the enlarged diameter portion 2g to the sliding contact surface (flat end surface 3i) of the hub wheel 31 is from the leading edge of the labyrin slip 62d to the sliding contact surface (flat end surface 3i) of the hub wheel 31. It is shorter than or equal to the distance. According to the wheel bearing device 1, the passage that is the gap between the outer member 2 and the hub wheel 31 is complicated, and the cross-sectional area of the passage is reduced, so that the foreign matter that reaches the labyrinth slip 62 d and the side lip 62 a. (Muddy water, dust, etc.) can be reduced. Therefore, high sealing performance by the outer side seal member 6 can be maintained.

  In addition, when the distance from the inner peripheral surface 2j of the enlarged diameter portion 2g of the outer member 2 to the outer peripheral surface 3m of the stepped portion 3h of the hub ring 31 is “D”, the distance D is the tip of the labyrin slip 62d. It is shorter or the same as the distance from the edge to the sliding contact surface (flat end surface 3i) of the hub wheel 31. Here, “same” means that the same microscopic difference is included in “same”.

  Thus, in the wheel bearing device 1 according to the third embodiment, the enlarged-diameter portion 2g is formed at the inner edge portion of the outer side end portion 2f of the outer member 2. The distance D from the inner peripheral surface 2j of the enlarged diameter portion 2g to the outer peripheral surface 3m of the stepped portion 3h of the hub wheel 31 is the distance from the leading edge of the labyrin slip 62d to the sliding contact surface (flat end surface 3i) of the hub wheel 31. Shorter or the same. According to the wheel bearing device 1, the passage that is the gap between the outer member 2 and the hub wheel 31 is complicated, and the cross-sectional area of the passage is reduced, so that the foreign matter that reaches the labyrinth slip 62 d and the side lip 62 a. (Muddy water, dust, etc.) can be reduced. Therefore, high sealing performance by the outer side seal member 6 can be maintained.

  Next, technical ideas applicable to the wheel bearing device 1 according to each embodiment will be described. FIG. 8 is a diagram showing the outer seal member 6 and the surrounding structure of the wheel bearing device 1 according to the fourth embodiment. Here, the description will be given mainly focusing on differences from the wheel bearing device 1 according to the first embodiment.

  In the wheel bearing device 1 according to the present embodiment, a drain groove 2k is formed on the outer periphery of the outer side end 2f of the outer member 2. The drain groove 2k is formed in the circumferential direction around the rotation axis A of the inner member 3 (hub wheel 31 and inner ring 32). For this reason, it is possible to collect foreign matters (such as muddy water and dust) that travel along the outer member 2 toward the outer seal member 6. Thereafter, foreign matter (muddy water, dust, etc.) is guided in the circumferential direction along the drainage groove 2k and falls as it is.

  Thus, in the wheel bearing device 1 according to the fourth embodiment, the drainage groove 2k is formed on the outer periphery of the outer side end portion 2f of the outer member 2. According to such a wheel bearing device 1, foreign matters (such as muddy water and dust) that travel toward the outer seal member 6 through the outer member 2 can be collected, so that they reach the labyrinth slip 62 d and the side lip 62 a. Foreign substances (such as muddy water and dust) can be reduced. Therefore, high sealing performance by the outer side seal member 6 can be maintained.

  The wheel bearing device 1 according to the present application includes an outer member 2 having a vehicle body mounting flange 2e, an inner member 3 in which one inner ring 32 is externally fitted to a hub ring 31, an outer member 2 and an inner member 3. It is a third generation structure of an inner member rotation specification composed of a plurality of rolling elements 41 and 41 interposed between the raceway surfaces 2c, 2d, 3c, and 3d, but the present invention is not limited to this. Absent. For example, an outer member formed as a hub ring, an inner member in which one inner ring is fitted to a support shaft having a vehicle body mounting flange, and an outer member and an inner member interposed between the raceway surfaces. And a third generation structure of an outer member rotation specification configured by a plurality of rolling elements.

  Finally, the invention in the present application is not limited to each embodiment, but is merely an example, and it goes without saying that the invention can be implemented in various forms without departing from the gist of the present invention. The scope of the invention is indicated by the description of the scope of claims, and includes all modifications within the equivalent meaning and scope of the scope of claims.

DESCRIPTION OF SYMBOLS 1 Wheel bearing apparatus 2 Outer member 2f Outer side edge part, 2g Diameter expansion part, 2i Diameter difference surface,
3 inner member 3a small diameter step, 3c inner raceway surface, 3d inner raceway surface,
3h step, 3i flat end surface (sliding contact surface),
3j Arc surface (sliding contact surface), 3m outer peripheral surface 31 hub wheel, 32 inner ring 4 rolling member 6 seal member (outer side seal member)
61 cored bar 62 elastic member 62a side lip 62d labyrin slip
62e Push-in surface

Claims (5)

An outer member having a double-row outer raceway surface formed on the inner periphery;
An inner member having a hub ring formed with a small-diameter stepped portion and an inner ring that is externally fitted to the small-diameter stepped portion, and a double row outer raceway surface formed on the outer periphery;
A plurality of rolling elements interposed between the raceway surfaces of the outer member and the inner member;
A seal member mounted on an outer opening end of an annular space formed between the outer member and the inner member;
The seal member is composed of a core metal fitted into the outer member and an elastic member fixed to the core metal;
One side lip is formed on the elastic member, the side lip extends at a predetermined angle with respect to the rotation axis of the inner member, and the tip edge of the side lip contacts the sliding contact surface of the hub wheel. In the wheel bearing device,
One labyrin slip is formed on the elastic member, the labyrin slip extends radially outside the side lip at an angle smaller than the predetermined angle, and the leading edge of the labyrin slip is in sliding contact with the hub wheel. Facing the surface through a labyrinth gap,
The wheel bearing device according to claim 1, wherein a pressing surface that does not overlap the labyrin slip in the axial direction and is perpendicular to the axial direction is formed outside the elastic member in the radial direction of the labyrin slip. The outer side end surface of the outer member and the sliding contact surface of the hub wheel are opposed to each other,
The distance from the outer side end surface of the outer member to the sliding contact surface of the hub wheel is shorter or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. The wheel bearing device according to claim 1. The sliding contact surface is provided at a stepped portion protruding to the inner side of the hub wheel;
The wheel bearing device according to claim 1, wherein an outer side end portion of the outer member is extended to a radially outer side of the stepped portion. An enlarged diameter portion is formed on the inner edge of the outer member on the outer side end,
The distance from the diameter difference surface in the enlarged diameter portion to the sliding contact surface of the hub wheel is shorter or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. The wheel bearing device according to claim 3. An enlarged diameter portion is formed on the inner edge of the outer member on the outer side end,
The distance from the inner peripheral surface of the enlarged diameter portion to the outer peripheral surface of the stepped portion of the hub wheel is shorter than or the same as the distance from the leading edge of the labyrin slip to the sliding contact surface of the hub wheel. The wheel bearing device according to claim 3.

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