JP2012166678A - Wheel support structure of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To arrange a seal member so as not to increase a rotation loss of a wheel, and to discharge water and dust from the hub part side.SOLUTION: This wheel support structure of a vehicle includes an axle 12 fixed to the vehicle body side and the wheel 14 journaled to the axle 12, the wheel 14 has a circular pipe-shaped hub part 25 extending along the axle 12, the wheel 14 is journaled to the axle 12 via a bearing 16 by the hub part 25 and is arranged outside in the axial direction of the bearing 16, and a dust seal 30 having an interference is arranged between an inner wall 28B of the hub part 25 and the axle 12. A labyrinth member 40 partially stored in a width of the hub part 25 and having a plurality of fin parts 45A and 45B extending outside in the radial direction from the stored part, is arranged outside in the axial direction of the dust seal material 30, and a lower part of the fin part 45B on the outermost side among the plurality of fin parts 45A and 45B, is cut out, and is formed as a drain part 51.

Description

  The present invention relates to a wheel support structure for a vehicle.

  Conventionally, in a vehicle wheel support structure, an axle fixed to the vehicle body side and a wheel pivotally supported by the axle, the wheel has a tubular hub portion extending along the axle, A structure is disclosed in which a wheel is pivotally supported on an axle via a bearing at a hub portion, and a collar on the outer side of the bearing forms a labyrinth with the hub portion. In this structure, there is no seal member that covers the bearing, but the labyrinth structure makes it difficult for water, dust, etc. to enter the bearing side, and the rotation loss of the wheel is reduced by the amount that the seal member is not provided. Thus, fuel consumption can be reduced by reducing friction (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 5-16604

However, in the conventional vehicle wheel support structure described above, the outside of the bearing is not sealed by the sealing member, so if water or dust enters the hub side beyond the labyrinth structure, the performance of the bearing may be affected. It is desirable to provide a seal member that covers the bearing between the axle and the hub portion. Moreover, in the said prior art, the water and dust which entered the hub part side will become difficult to be discharged | emitted outside by a labyrinth structure. For this reason, while providing a sealing member so that the rotation loss of a wheel may not be increased, it becomes a subject to be able to discharge | emit water and dust efficiently from the hub part side.
The present invention has been made in view of the circumstances described above, and in a vehicle wheel support structure, a seal member is provided so as not to increase the rotation loss of the wheel, and water and dust can be discharged from the hub portion side. The purpose is to.

In order to achieve the above object, the present invention comprises an axle (12, 312) fixed to the vehicle body side and a wheel (14, 314) supported on the axle (12, 312). 14, 314) has a tubular hub portion (25, 325) extending along the axle (12, 312), and the wheel (14, 314) is the hub portion (25, 325). The bearing (16) is pivotally supported by the axle (12, 312) and is provided on the outer side in the axial direction of the bearing (16), and the inner wall (28B, 328B) of the hub portion (25, 325) and the In a vehicle wheel support structure in which a seal member (30) having a tightening allowance is provided between the axle (12, 312), the hub portion (25, 325) is disposed outside the seal member (30) in the axial direction. Some within the width A labyrinth member (40, 240, 340) having a plurality of fin portions (45A, 45B, 245C, 345A, 345B) that is accommodated and extends radially outward from the accommodated portion is provided, and the plurality of fin portions ( 45A, 45B, 245C, 345A, 345B), the lower part of the outermost fin portion is cut out to form drainage portions (51, 252, 351).
According to this configuration, the wheel is pivotally supported by the axle through the bearing at the tubular hub portion, and the seal member having a tightening margin is provided between the inner wall of the hub portion and the axle, and within the width of the hub portion. Since a labyrinth member having a plurality of fin portions that are partly accommodated and extending radially outward from this portion is provided, the labyrinth member can prevent water and dust from entering the hub portion, and a seal member that is generated by tightening allowance It is possible to suppress the entry of water and dust into the bearing without increasing the tension. For this reason, a seal member can be provided between the axle and the hub so as not to increase the rotation loss of the wheel, and fuel consumption can be reduced. Furthermore, since the lower part of the outermost fin part of the fin part of the labyrinth member is cut out to form a drainage part, water and dust can be quickly discharged from the lower part of the fin part, and the outermost fin part Intrusion of water and dust can be suppressed at the inner fin portion. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing.

In the above configuration, the fin portion (45A, 45B, 245C, 345A, 345B) of the labyrinth member (40, 240, 340) and the inner wall of the hub portion (25, 325) of the wheel (14, 314). (28B, 328B) and radial gaps (Q, W) are provided smaller than the grooves (P, T, U) between the plurality of fin portions (45A, 45B, 245C, 345A, 345B). Also good.
In this case, since the radial gap between the fin portion of the labyrinth member and the inner wall of the hub portion of the wheel is smaller than the groove between the plurality of fin portions, the dust that has entered the groove between the fin portions is separated by the gap. Since it is difficult to enter between the smaller fin portion and the inner wall of the hub portion and is discharged through the groove between the fin portions, it is possible to suppress the entry of dust into the seal member side.

Further, an outer cover part (43) positioned axially outside the hub part (25) is provided outside the labyrinth member (40) with respect to the wheel center, and the outer cover part (43) and It is good also as a structure by which the clearance gap between the axial direction outer side edge part (28A) of the said hub part (25) is provided smaller than the groove | channel (P) between the said several fin parts (45A, 45B).
In this case, since the outer cover portion of the labyrinth member is provided on the outer side in the axial direction than the hub portion, the outer cover portion can further reduce the intrusion of water and dust into the hub portion side, and the shaft of the outer cover portion and the hub portion can be reduced. Since the gap between the outer end portion in the direction is smaller than the dimension between the fin portions, the size of dust entering between the fin portions from the gap between the outer cover portion and the outer end portion in the axial direction of the hub portion is reduced. This dust tends to fall through the fins. For this reason, intrusion of dust into the seal member side can be suppressed.

Further, the vehicle has an axle holding member (11) for holding the axle (12), and a locking portion (49) is provided on the outer cover portion (43) of the labyrinth member (40), It is good also as a structure by which the detent | locking part (17) which latches the said latching | locking part (49) is provided in an axle shaft holding member (11).
In this case, since the latching | locking part of a labyrinth member can be stopped by the rotation prevention part provided in an axle shaft holding member, the position of a drainage part can be controlled below and water can be discharged | emitted from a labyrinth member efficiently.
Furthermore, a drain hole (52) of the labyrinth member (40) is provided in the outer cover part (43), and a side bulge part (50) covering the side of the drain hole (52). May be provided in the outer cover part (43).
In this case, water and dust can be efficiently discharged from the drain hole of the outer cover part, and intrusion of water and dust from the drain hole can be suppressed by the side bulging portion that covers the side of the drain hole.

The area of the drain hole (52) may be larger than the cross-sectional area of the groove (P) between the plurality of fins (45A, 45B) of the labyrinth member (40).
In this case, since the area of the drain hole is larger than the cross-sectional area of the groove between the fin portions, water and dust can be efficiently discharged from the drain hole.
Further, among the plurality of fin portions (45A, 45B, 245C), two or more outermost portions are provided with lower notches, and inside the plurality of fin portions (45A, 45B, 245C), A fin part is good also as a structure by which the clearance gap between the said hub parts (25) is made constant.
In this case, since the lower notch is provided in the outermost two or more of the plurality of fin portions, water and dust can be efficiently discharged from the drainage portion, and the inner and inner fins of the plurality of fin portions can be efficiently discharged. Since the gap between the part and the hub part is made constant, entry of water and dust into the seal member can be suppressed by the inner fin part.

Further, the axle (12) has a collar member (32) arranged adjacent to the outside of the bearing (16), and the collar member (32) is a locking recess (34) along the circumferential direction. It is good also as a structure by which the latching convex part (41B) latched by this latching recessed part (34) is provided in the said labyrinth member (40).
In this case, the labyrinth member can be easily fixed by locking the locking concave portion of the collar member arranged adjacent to the outer side of the bearing to the locking convex portion of the labyrinth member. For this reason, the labyrinth member can be provided at low cost and light weight, and the clearance between the labyrinth member and the wheel can be easily secured.

The present invention also includes a tubular shaft support portion (428) provided on the vehicle body side, and a wheel (414) pivotally supported by the shaft support portion (428), and a hub portion of the wheel (414). (425) has a shaft portion (412) extending along the shaft support portion (428), and the shaft portion (412) is pivotally supported on the shaft support portion (428) via a bearing (416). And a seal member (30) provided on the outer side in the axial direction of the bearing (416) and having a tightening margin between the inner wall (428B) of the shaft support portion (428) and the hub portion (425). In the vehicle wheel support structure, a plurality of fins (which are accommodated within the width of the shaft support portion (428) outside the seal member (30) in the axial direction and extend radially outward from the accommodated portion. 445A, 445B, 445 ) And a portion near the fin portion on the outer side in the axial direction in the plurality of fin portions (445A, 445B, 445C) is notched in the lower portion of the shaft support portion (428). The water draining portion (451) is used.
In this case, the wheel is supported on the vehicle body side via a bearing by a tubular shaft support portion provided on the vehicle body side, and a seal member having a tightening margin is provided between the inner wall of the shaft support portion and the hub portion. Since the labyrinth portion having a plurality of fin portions that are accommodated within the width of the shaft support portion and extend radially outward from the accommodated portion is provided, water and dust can enter the hub portion side by the labyrinth portion. Intrusion of water and dust into the bearing can be suppressed without increasing the tightening force of the seal member generated by the tightening allowance. For this reason, a sealing member can be provided between the hub portion and the shaft support portion so as not to increase the rotation loss of the wheel, and fuel consumption can be reduced. Furthermore, since a portion near the fin portion on the outside in the axial direction is cut out in the lower portion of the shaft support portion to form a drainage portion, water and dust can be quickly discharged from the lower portion of the shaft support portion. While being able to discharge | emit, the penetration | invasion of water and dust can be suppressed in the fin part inside the outermost fin part. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing.

  In the vehicle wheel support structure according to the present invention, since the labyrinth member having a plurality of fins extending radially outward is provided in the hub portion, water and dust can be prevented from entering the hub portion by the labyrinth member and tightened. It is possible to suppress the intrusion of water and dust into the bearing without increasing the tightening force of the seal member generated by the cost. For this reason, a seal member can be provided between the axle and the hub so as not to increase the rotation loss of the wheel, and fuel consumption can be reduced. Furthermore, since the lower part of the outermost fin part of the fin part is cut out to form a drainage part, water and dust can be quickly discharged from the lower part of the fin part, and the inner part of the outermost fin part can be removed. Water and dust can be prevented from entering at the fins. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing.

Further, since the radial gap between the fin portion and the inner wall of the hub portion of the wheel is smaller than the groove between the plurality of fin portions, dust that has entered the groove between the fin portions has a smaller gap than the groove. Since it is difficult to enter between the portion and the inner wall of the hub portion and is discharged through the groove between the fin portions, it is possible to suppress the entry of dust into the seal member side.
In addition, since the outer cover part is provided on the outer side in the axial direction than the hub part, water and dust can be further prevented from entering the hub part side, and the gap between the outer cover part and the axially outer end of the hub part can be reduced. Since it is provided smaller than the dimension between the fin parts, the size of dust entering between the fin parts from this gap is small, and this dust tends to fall through the fin parts. For this reason, intrusion of dust into the seal member side can be suppressed.

Furthermore, since the latching | locking part of a labyrinth member can be stopped by the rotation prevention part provided in an axle shaft holding member, the position of a drainage part can be controlled below and water can be discharged | emitted efficiently from a labyrinth member.
In addition, water and dust can be efficiently discharged from the drain hole of the outer cover portion, and water and dust can be prevented from entering from the drain hole by the side bulging portion that covers the side of the drain hole.

Moreover, since the area of the drain hole is larger than the cross-sectional area of the groove between the fin portions, water and dust can be efficiently discharged from the drain hole.
In addition, since the lower notch is provided in the outermost two or more of the plurality of fin portions, water and dust can be efficiently discharged from the drain portion, and the inner fin portion among the plurality of fin portions Since the gap with the hub portion is made constant, the inner fin portion can suppress the entry of water and dust into the seal member.
Furthermore, the labyrinth member can be easily fixed by locking the locking concave portion of the collar member to the locking convex portion of the labyrinth member. For this reason, the labyrinth member can be provided at low cost and light weight, and the clearance between the labyrinth member and the wheel can be easily secured.

  In addition, since the labyrinth portion having a plurality of fin portions extending radially outward is provided in the shaft support portion, water and dust can be prevented from entering the hub portion side by the labyrinth portion, and the tightness of the seal member caused by tightening allowance Water and dust can be prevented from entering the bearing without increasing the force. For this reason, a sealing member can be provided between the hub portion and the shaft support portion so as not to increase the rotation loss of the wheel, and fuel consumption can be reduced. Furthermore, since a portion near the fin portion on the outside in the axial direction is cut out in the lower portion of the shaft support portion to form a drainage portion, water and dust can be quickly discharged from the lower portion of the shaft support portion. While being able to discharge | emit, the penetration | invasion of water and dust can be suppressed in the inner fin part from the outermost fin part. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing.

1 is a front sectional view showing a front portion of a motorcycle to which a wheel support structure according to a first embodiment of the present invention is applied. It is an expanded sectional view of the vicinity of a bearing accommodating part. It is the side view which looked at the front fork and labyrinth member from the vehicle left side. It is the figure which looked at the hub part and the labyrinth member from the lower part. It is an expanded sectional view of the vicinity of the bearing accommodating part in 2nd Embodiment. It is a figure which shows a labyrinth member. It is sectional drawing which shows the wheel support structure of 3rd Embodiment. It is an expanded sectional view of the vicinity of a bearing accommodating part. It is sectional drawing which shows the wheel support structure of 4th Embodiment. It is an expanded sectional view of the vicinity of a bearing accommodating part.

  Hereinafter, a wheel support structure for a vehicle according to each embodiment of the present invention will be described with reference to the drawings. Note that the directions such as front, rear, left and right in the following description are the same as those in the vehicle described below unless otherwise specified. In addition, arrows FR indicating the front of the vehicle, an arrow LH indicating the left side of the vehicle, and an arrow UP indicating the upper side of the vehicle are shown at appropriate positions in the drawings used for the following description.

[First Embodiment]
FIG. 1 is a front sectional view showing a front portion of a motorcycle to which a wheel support structure according to a first embodiment of the present invention is applied.
The motorcycle 1 (vehicle) is a straddle-type motorcycle having a vehicle body between a front wheel 10 and a rear wheel (not shown). The vehicle body is supported by a vehicle body frame (not shown) and the vehicle body frame. An engine (not shown), a swing arm (not shown) provided at the rear of the body frame and rotatably supporting the rear wheel, and supported at the front of the body frame so as to be steerable left and right. In addition, a tube-shaped front fork 11 (axle holding member) that rotatably supports the front wheel 10 is provided. The front fork 11 is provided as a pair of left and right, but the front fork on the right side of the vehicle is not shown here.

The wheel support structure for supporting the front wheel 10 is configured such that both ends of an axle 12 extending in the vehicle width direction are supported by lower portions of the left and right front forks 11 and the front wheel 10 is pivotally supported on the axle 12 between the left and right front forks 11. Has been.
The front fork 11 is configured by combining upper and lower divided tubes. A block-shaped shaft support portion 11B is provided at the lower end of the lower tube 11A, and the shaft support portion 11B penetrates in the vehicle width direction. An axle support hole 11C is formed, and the axle 12 is inserted through the axle support hole 11C.

  The front wheel 10 is configured by attaching a rubber tire 13 to a wheel 14. The wheel 14 includes a hub 20 through which the axle 12 is inserted, an annular rim 21 that is provided coaxially with the hub 20 and that forms an outer edge of the wheel 14, and an outer peripheral portion of the hub 20 and an inner peripheral portion of the rim 21. A plurality of spokes 22 spanned in between and integrally connecting the hub 20 and the rim 21, and a pair of left and right bearings 15, 16 provided on the hub 20 and rotatably supporting the wheel 14 on the axle 12. ing.

  The hub 20 includes a tubular hub portion 25 that extends in the vehicle width direction along the axle 12, and a spoke connection portion 26 that is formed on the outer periphery of the hub portion 25 and to which the spokes 22 are connected. Yes. The bearings 15 and 16 are press-fitted into the hub portion 25, and cylindrical bearing accommodating portions 27 and 28 for accommodating the bearings 15 and 16 are formed at both ends in the axial direction inside the hub portion 25, respectively. Yes.

The bearing 15 is press-fitted into the right bearing housing portion 27 alone. The left bearing housing portion 28 is formed deeper than the bearing housing portion 27, and the bearing 16 is press-fitted into the bearing housing portion 28 at the most central side in the axial direction of the bearing housing portion 28. A ring-shaped dust seal 30 (seal member) is disposed outside, and a ring-shaped labyrinth member 40 is disposed outside the dust seal 30. Further, a cylindrical collar member 32 interposed between the bearing 16 and the shaft support portion 11B is disposed in the bearing housing portion 28. The collar member 32 is provided through the dust seal 30 and the labyrinth member 40.
A space portion 33 having a smaller diameter than the bearing housing portions 27 and 28 is formed between the bearing housing portions 27 and 28 in the hub portion 25, and a guide pipe 29 through which the axle 12 is inserted is disposed in the space portion 33. Is done.

FIG. 2 is an enlarged cross-sectional view of the vicinity of the bearing accommodating portion 28.
As shown in FIGS. 1 and 2, the bearings 15 and 16 are ball bearings, and outer races 15A and 16A that are press-fitted into the bearing housing portions 27 and 28, inner races 15B and 16B through which the axle 12 is inserted, and outer races. Balls 15C, 16C provided between 15A, 16A and inner races 15B, 16B.

The axle 12 has a bolt head portion 12B at one end of the shaft portion 12A, and has a male screw portion (not shown) to which a nut (not shown) is fastened at the other end of the shaft portion 12A. ing.
The front wheel 10 includes a bolt head 12B that contacts the outer surface of the left shaft support portion 11B and a shaft support portion below the right front fork in a state where the axle 12 is inserted through the left and right front forks 11 and the hub portion 25. It is fixed to the front fork 11 by a fastening force between the nut abutting on the outer surface (not shown). Specifically, the shaft support portion of the right front fork, the inner race 15B, the guide pipe 29, the inner race 16B, the collar member 32, and the shaft support portion 11B are compressed in the axial direction of the axle 12 by the fastening force of the axle 12. The inner race 15 </ b> B, the guide pipe 29, the inner race 16 </ b> B, and the collar member 32 cannot be rotated in the hub portion 25. The hub 14 rotates relative to the inner races 15B, 16B fixed to the axle 12 side together with the outer races 15A, 16A via the balls 15C, 16C, so that the wheel 14 rotates relative to the axle 12. Become.

The collar member 32 has a small diameter portion 32A that contacts the inner race 15B, a large diameter portion 32B that contacts the shaft support portion 11B, and an inner diameter portion 32C through which the axle 12 is inserted, and the outer peripheral surface of the large diameter portion 32B. Is provided with an annular locking recess 34 extending in the circumferential direction.
The dust seal 30 includes a ring-shaped seal body 35 formed by embedding a metal ring 35 </ b> A inside a rubber-like elastic body, and an annular lip portion 36 provided on the inner peripheral surface of the seal body 35. Yes. A pair of lip portions 36 project radially inward from both axial ends of the dust seal 30, and a groove between the pair of lip portions 36 is filled with grease.

  The dust seal 30 covers the bearing 16 from the outside in the axle direction, thereby suppressing water and dust from entering the bearing 16 side. The dust seal 30 is fixed by press-fitting the outer peripheral portion of the seal body 35 into the bearing housing portion 28, and rotates integrally with the wheel 14 when the wheel 14 rotates. A collar member 32 is inserted into the inner diameter portion of the dust seal 30 so as to deform the lip portion 36 by the amount of the tightening allowance. As a reaction force of the deformation of the lip portion 36, there is a gap between the dust seal 30 and the collar member 32. The tightening force of the dust seal 30 is generated. The lip portion 36 is brought into close contact with the collar member 32 by this tightening force, and high sealing performance is obtained. When the wheel 14 rotates, the lip portion 36 rotates relative to the collar member 32, and friction is generated between the lip portion 36 and the outer peripheral surface of the collar member 32 according to the tightening force.

  The labyrinth member 40 is provided so as to close the axially open end 28A (the axially outer end) of the bearing accommodating portion 28, and suppresses the entry of water and dust into the bearing accommodating portion 28. The labyrinth member 40 includes a base 41 that is formed in a ring shape and is attached to the large-diameter portion 32B of the collar member 32, a ring-shaped accommodation portion 42 that is accommodated in the bearing accommodation portion 28, and an opening in the bearing accommodation portion 28. The outer cover part 43 which covers the end 28A from the outside is provided. A part of the base 41 is also located in the bearing accommodating portion 28 and serves as a accommodated portion 42. The labyrinth member 40 is formed by integrally molding a resin material.

  The base 41 has an inner peripheral portion 41A that fits to the outer peripheral surface of the collar member 32, and an annular locking convex portion 41B that extends along the circumferential direction of the inner peripheral portion 41A. The convex portion 41 </ b> B is fitted in the locking concave portion 34 of the collar member 32 and is locked in the axial direction.

  The accommodated portion 42 has a cylindrical portion 44 that extends in the axial direction from the outer peripheral portion of the base portion 41 to the vicinity of the dust seal 30, and the cylindrical portion 44 is formed with a plurality of fin portions 45 </ b> A and 45 </ b> B that extend radially outward. . The fin portions 45A and 45B are hook-like convex portions extending along the circumferential direction of the outer peripheral surface 44A of the cylindrical portion 44, and are formed so as to make a round around the outer peripheral surface 44A. As described above, by providing the plurality of fin portions 45A and 45B, a labyrinth structure is formed in the bearing housing portion 28, and entry of water and dust into the dust seal 30 and the bearing 16 side can be suppressed.

  A groove P having a width in the axial direction is formed between a fin portion 45A on the distal end side of the cylindrical portion 44 and a fin portion 45B located outside the fin portion 45A. The heights of the fin portions 45A and 45B are substantially the same, and a gap Q is formed in the radial direction between the tip of the fin portions 45A and 45B and the inner wall 28B of the bearing housing portion 28, and the fin portion 45A. 45B do not contact the inner wall 28B. A space 47 is formed between the fin portion 45 </ b> B and the dust seal 30 and between the tube portion 44 and the collar member 32.

  The outer cover portion 43 is formed in a disc shape extending radially outward from the base portion 41, and is provided so as to be positioned on the axially outer side of the hub portion 25 so as to close the opening end 28A. The outer diameter of the outer cover portion 43 is substantially the same as the outer diameter of the opening end 28A. A gap R is formed in the axial direction between the inner surface 43A in the axial direction of the outer cover portion 43 and the opening end 28A, and the outer cover portion 43 does not contact the opening end 28A.

  A groove S having a width in the axial direction is formed between the inner surface portion 43A of the outer cover portion 43 and the fin portion 45B. The axial length of the groove S is the groove between the fin portions 45A and 45B. It is substantially the same as the length of P. Further, the size of the gap Q in the radial direction is smaller than the length of the grooves S and P in the axial direction. Further, the size of the gap R in the axial direction is smaller than the length of the grooves S and P in the axial direction.

FIG. 3 is a side view of the front fork 11 and the labyrinth member 40 as viewed from the left side of the vehicle. In FIG. 3, the front fork 11 is indicated by a two-dot chain line, and the wheel 14 is not shown. FIG. 4 is a view of the hub portion 25 and the labyrinth member 40 as viewed from below.
As shown in FIGS. 2 and 3, the front fork 11 is provided to be inclined rearward by the caster angle, and a detent portion 17 protruding toward the labyrinth member 40 is provided at the lower end of the lower tube 11A. .
A groove-shaped locking part 49 is formed on the outer surface 43B of the outer cover part 43 so as to face the lower tube 11A, and the labyrinth member 40 has the locking part 49 of the outer cover 43 at the lower part. By being engaged with the rotation preventing portion 17 of the tube 11A, the tube is locked in the circumferential direction and is prevented from rotating.
Further, a laterally bulging portion 50 that bulges toward the lower tube 11 </ b> A is formed at the lower portion of the outer surface portion 43 </ b> B of the outer cover portion 43.

  The fin portion 45B is positioned on the outermost side in the axial direction among the plurality of fin portions 45A and 45B, and the drain portion 51 is formed by forming the opening in the lower portion of the fin portion 45B by cutting the fin portion 45B. Is provided. In the lower part of the labyrinth member 40, the water drainage 51 is formed so that the groove P and the groove S communicate with each other. On the other hand, notches are not formed in the fin portion 45A located on the innermost side. That is, in the fin portion 45A, the gap Q is formed to be constant and narrow over the entire circumference, and it is difficult for water and dust to enter the bearing 16 side beyond the fin portion 45A.

In addition, a drain hole 52 is formed in the lower portion of the outer cover portion 43 to allow the groove S between the fin portion 45 </ b> B and the outer cover portion 43 to communicate with the outside below the outer cover portion 43. The drain hole 52 is formed so as to cut out a part on the inner surface side of the side bulging portion 50. As shown in FIG. 4, the drain hole 52 is formed in a substantially rectangular shape when viewed from below, and the area of the drain hole 52 when viewed from below is the groove P when viewed from the side surface shown in FIG. And the groove S is formed larger than each cross-sectional area.
Further, since the drain hole 52 is covered on the side by the outer cover part 43 and is opened only downward, it is possible to prevent water and dust from entering the drain hole 52 from the side.

  When attaching the front wheel 10, the collar member 32 with the labyrinth member 40 attached thereto is set on the dust seal 30 of the wheel 14, and then the anti-rotation portion 17 is engaged with the locking portion 49 so that the labyrinth member 40 is engaged. Then, the axle 12 is inserted into the front fork 11 and the wheel 14 and the axle 12 is fastened. Thus, since the labyrinth member 40 can be assembled together with the collar member 32 and can be positioned by the detent portion 17, the assembly is easy.

Next, the operation of the wheel support structure of the first embodiment will be described.
Although water and dust enter from between the labyrinth member 40 and the opening end 28A of the bearing housing portion 28, the opening end 28A is covered by the outer cover portion 43 of the labyrinth member 40 in the first embodiment. , Water and dust can be prevented from entering the bearing housing portion 28 from the outside. Even if water or dust enters the bearing housing portion 28, the labyrinth structure constituted by the fin portions 45A and 45B can prevent water and dust from entering the dust seal 30 and the bearing 16 side. The water and dust collected by 45B fall down through the grooves P and S of the fin portions 45A and 45B, reach the drain portion 51 formed at the lower portion of the labyrinth member 40, and then drain the water. It is discharged to the outside through the hole 52.

Here, since the size of the gap Q in the radial direction is smaller than the length of the grooves S and P in the axial direction, the dust that has entered the grooves S and P of the fin portions 45A and 45B has the gap S , P is less likely to enter the gap Q, and most of it is discharged through the grooves S, P. For this reason, intrusion of dust to the bearing 16 side can be suppressed.
Furthermore, since the size of the gap R in the axial direction is smaller than the length of the grooves S and P in the axial direction, the size of dust entering the grooves S and P of the fin portions 45A and 45B from the gap R is as follows. The dust becomes smaller than the lengths of the grooves S and P, and this dust easily falls through the grooves S and P. For this reason, intrusion of dust to the bearing 16 side can be suppressed.
Moreover, since the area (FIG. 4) of the drain hole 52 when viewed from below is formed larger than the sectional area (FIG. 2) of the groove S when viewed from the side surface, water and dust are drained. The holes 52 can be efficiently discharged.

Moreover, since the drainage part 51 is provided in the outermost fin part 45B and the gap Q is constant without providing a notch in the innermost fin part 45A, water and dust can be efficiently discharged from the drainage part 51. However, intrusion of water and dust can be prevented by the fin portion 45A.
Since the labyrinth member 40 can suppress the intrusion of water and dust into the bearing housing portion 28, the pressing force of the dust seal 30 against the collar member 32 on the axle 12 side can be set small. For this reason, the friction between the dust seal 30 and the collar member 32 is reduced, and the fuel efficiency of the motorcycle 1 can be reduced.
Further, the labyrinth member 40 is provided in the bearing housing portion 28 with a gap R and a gap Q. Since the labyrinth member 40 is not in contact with the wheel 14, water and dust can be prevented without impeding the rotation of the wheel 14. Intrusion can be reduced.

  As described above, according to the first embodiment to which the present invention is applied, the wheel 14 is pivotally supported by the axle 12 via the bearing 16 with the circular hub portion 25, and the bearing housing portion of the hub portion 25. A dust seal 30 having a tightening margin is provided between the inner wall 28B of the vehicle 28 and the axle 12, and a part of the dust seal 30 is accommodated within the width of the bearing accommodating portion 28, and a plurality of fin portions 45A, 45B extending radially outward from this portion. Since the labyrinth member 40 is provided, water and dust can be prevented from entering the hub portion 25 by the labyrinth member 40, and water or dust can be applied to the bearing 16 without increasing the tightening force of the dust seal 30 caused by the tightening allowance. Intrusion can be suppressed. For this reason, the dust seal 30 can be provided between the axle 12 and the hub portion 25 so as not to increase the rotation loss of the wheel 14, and the fuel efficiency of the motorcycle 1 can be reduced. Furthermore, since the lower part of the outermost fin part 45B in the fin parts 45A and 45B of the labyrinth member 40 is cut out to form the drain part 51, water and dust can be promptly removed from the lower part of the fin parts 45A and 45B. While being able to discharge | emit, penetration | invasion of water and dust can be suppressed in the fin part 45A inside the outermost fin part 45B. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing 16.

Moreover, since the radial gap Q between the fin portions 45A and 45B of the labyrinth member 40 and the inner wall 28B of the hub portion 25 of the wheel 14 is smaller than the groove P of the fin portions 45A and 45B, dust that has entered the groove P Since the gap is less likely to enter the gap Q than the groove P and is discharged through the groove P of the fin portions 45A and 45B, the intrusion of dust into the dust seal 30 and the bearing 16 side can be suppressed.
Further, since the outer cover portion 43 of the labyrinth member 40 is provided on the outer side in the axial direction than the hub portion 25, the outer cover portion 43 can further reduce the intrusion of water and dust to the hub portion 25 side, and the outer cover portion 43. Since the clearance R between the opening portion 28A of the hub portion 25 is smaller than the groove P between the fin portions 45A and 45B, the size of dust entering the groove P between the fin portions 45A and 45B from the clearance R is small. This dust is more likely to fall through the groove P than through the gap Q. For this reason, intrusion of dust to the dust seal 30 and the bearing 16 side can be suppressed.

Furthermore, since the locking part 49 of the labyrinth member 40 can be prevented from being rotated by the rotation preventing part 17 provided on the lower tube 11A of the front fork 11, the position of the drainage part 51 can be restricted downward, and water can be removed from the labyrinth member 40. Dust can be discharged efficiently.
Furthermore, water and dust can be efficiently discharged from the drain hole 52 of the outer cover part 43, and water and dust enter the drain hole 52 by the side bulging part 50 that covers the side of the drain hole 52. This can be suppressed.

Moreover, since the area of the drain hole 52 seen from the lower side is larger than the cross-sectional area of the groove P between the fin portions 45A and 45B when viewed from the side, water and dust can be efficiently discharged from the drain hole 52.
In addition, the labyrinth member 40 can be easily fixed by engaging the locking recess 34 of the collar member 32 disposed adjacent to the outer side of the bearing 16 with the locking projection 41B of the labyrinth member 40. For this reason, the labyrinth member 40 can be provided at low cost and light weight, and the clearance between the labyrinth member 40 and the wheel 14 can be easily secured.

In addition, the said embodiment shows the one aspect | mode which applied this invention, Comprising: This invention is not limited to the said embodiment.
In the first embodiment, the configuration in which the labyrinth member 40 is provided in the left bearing accommodating portion 28 has been described as an example. However, the present invention is not limited to this, and the right bearing accommodating portion 27 is not limited thereto. May be configured in the same manner as the bearing housing portion 28, and the labyrinth member 40 may be provided in the bearing housing portion 27.
In the first embodiment, the wheel support structure for supporting the front wheel 10 has been described as an example. However, the present invention is not limited to the position where the wheel is supported. You may apply this invention to the wheel support structure to support.

[Second Embodiment]
Hereinafter, a second embodiment to which the present invention is applied will be described with reference to FIGS. 5 and 6. In the second embodiment, parts that are configured in the same manner as in the first embodiment are given the same reference numerals, and descriptions thereof are omitted.
The second embodiment is different from the first embodiment mainly in that the outer cover portion 43 of the first embodiment is not provided.

FIG. 5 is an enlarged cross-sectional view of the vicinity of the bearing housing portion 28 in the second embodiment.
As shown in FIG. 5, the bearing housing 28 is provided with a bearing 16, a dust seal 30, a collar member 32, and a labyrinth member 240 that fits on the outer peripheral surface of the collar member 32.
The collar member 32 has a large-diameter portion 232B into which the labyrinth member 240 is fitted, and a plurality of concave portions 234 arranged at intervals in the circumferential direction are provided on the outer peripheral surface of the large-diameter portion 232B.

The labyrinth member 240 has a base portion 41, a accommodated portion 42, and a cylindrical portion 44. The labyrinth member 240 is formed by integrally molding a resin material. The base 41 has a plurality of protrusions 241B arranged on the inner peripheral surface 241A at intervals in the circumferential direction. The protrusions 241B engage with the recesses 234 of the collar member 32, so that the labyrinth member 240 Positioned in the axial direction. For this reason, the labyrinth member 240 can be fixed with a simple structure.
In the cylindrical portion 44, fin portions 45A, 45B, and 245C are formed in the axial direction from the dust seal 30 side. The fin portion 245C is located on the outer side of the fin portion 45B and is located on the outermost side in the axial direction. The axial end surface of the fin portion 245C substantially coincides with the axial position of the opening end 28A. ing. The fin portion 245C is a bowl-shaped convex portion that goes around the outer peripheral surface 44A.

A groove P is formed in the axial direction between the fin portion 45A and the fin portion 45B, and a groove T having a width in the axial direction is formed between the fin portion 45B and the fin portion 245C. The lengths of the grooves P and T in the axial direction are substantially equal.
The heights of the fin portions 45A, 45B, and 245C are substantially the same, and a gap Q is formed in the radial direction between the tip of the fin portions 45A, 45B, and 245C and the inner wall 28B of the bearing housing portion 28. The fin portions 45A, 45B, 245C do not contact the inner wall 28B.
The size of the gap Q in the radial direction is smaller than the length of the grooves P and T in the axial direction. Thus, by providing the fin portion 245C having the gap Q smaller than the length of the grooves P and T on the inner side of the opening end 28A, it is possible to suppress the intrusion of water and dust into the labyrinth member 240 and the grooves P and T. Even if water or dust enters the water, it is easier for water and dust to pass through the grooves P and T than through the gap Q between the fin portions 45A and 45B. Can be suppressed.

FIG. 6 is a view showing the labyrinth member 240, FIG. 6 (a) is a side view of the labyrinth member 240 and the collar member 32 as seen from the vehicle left side, and FIG. 6 (b) is the hub portion 25. And it is the figure which looked at the labyrinth member 240 from the lower part.
As shown in FIGS. 5 and 6, the labyrinth member 240 has a tubular outer extension portion 243 that extends outward along the collar member 32, and the lower portion of the outer extension portion 243 extends below 245C. A side cover portion 250 is formed extending to the side. The side cover portion 250 covers the lower portion of the opening end 28A from the side in a state where a gap is formed with respect to the lower portion of the opening end 28A. A drain hole 253 is formed in the lower portion of the side cover portion 250 to allow the outermost groove T to communicate with the lower outside of the side cover portion 250. The drain hole 253 is formed so as to cut out a part of the inner surface side of the side cover portion 250.

  In the lower part of the fin part 45B, the fin part 45B is notched and an opening is formed to form a drain part 251. In the lower part of the fin part 245C, the fin part 245C is notched and an opening is formed. As a result, a drainage portion 252 is provided. In the lower part of the labyrinth member 240, the drainage portion 251 is formed so that the groove P and the groove T communicate with each other, and the drainage portion 252 is formed so that the groove T and the drainage hole 253 communicate with each other. Thereby, the water and dust in the groove P and the groove T are discharged to the outside through the drainage portions 251 and 252 and the drainage hole 253. On the other hand, notches are not formed in the fin portion 45A located on the innermost side.

As shown in FIG. 6B, the drain hole 253 is formed in a substantially rectangular shape when viewed from below, and the area of the drain hole 253 when viewed from below is when viewed from the side surface shown in FIG. The cross-sectional areas of the groove P and the groove T are formed larger. For this reason, water and dust can be efficiently discharged from the drain hole 253.
Moreover, since the drain hole 253 is covered by the side cover part 250 and is opened only downward, it is possible to prevent water and dust from entering the drain hole 253 from the side.

  According to the second embodiment, of the plurality of fin portions 45A, 45B, 245C, the outermost two fin portions 45B, 245C are formed with lower notches to provide the drainage portions 251, 252. Therefore, water and dust can be efficiently discharged from the drainage portions 251 and 252, and the innermost fin portion 45 </ b> A has a constant gap Q with the inner wall 28 </ b> B of the bearing housing portion 28. Intrusion of water and dust into the dust seal 30 and the bearing 16 side can be suppressed by 45A.

In addition, the said 2nd Embodiment shows the one aspect | mode which applied this invention, Comprising: This invention is not limited to the said embodiment.
In the said 2nd Embodiment, although the lower notch was formed in two outermost fin parts 45B and 245C among three fin parts, it demonstrated as what is provided with the drainage parts 251 and 252, The present invention is not limited to this. For example, four or more fin portions are provided, the outermost two or more fin portions are provided with lower notches, and the innermost fin portion is the bearing housing portion. You may form so that the clearance gap Q with the inner wall 28B of 28 may become fixed.

[Third Embodiment]
Hereinafter, a third embodiment to which the present invention is applied will be described with reference to FIGS. In the third embodiment, parts that are configured in the same manner as in the first embodiment are given the same reference numerals, and descriptions thereof are omitted.
In the third embodiment, the wheel support structure of the present invention is applied to an ATV (All Terrain Vehicle) that is a rough terrain vehicle.

FIG. 7 is a cross-sectional view showing the wheel support structure of the third embodiment.
The rough terrain vehicle 300 (hereinafter referred to as a vehicle) is a four-wheeled vehicle having wheels on the front, rear, left and right of the vehicle body, and FIG. 7 is a cross-sectional view of the support structure for the left front wheel 310 of the vehicle 300 as viewed from the rear. It is.
The wheel support structure of the vehicle 300 includes an axle holding member 311 provided on the vehicle body side, an axle 312 fixed to the axle holding member 311, and a front wheel 310 pivotally supported on the axle 312.

The front wheel 310 is configured by assembling a tire (not shown) on the wheel 314, and the wheel 314 is provided by integrally connecting a rim (not shown) on which the tire is assembled to a hub 320 through which the axle 312 is inserted. The wheel 314 is pivotally supported on the axle 312 via a pair of left and right bearings 15 and 16 provided on the hub 320.
The hub 320 has a tubular hub portion 325 extending in the vehicle width direction along the axle 312 and a rim connecting portion 326 extending in the radial direction from the hub portion 325.
Cylindrical bearing accommodating portions 327 and 328 for accommodating the bearings 15 and 16 are formed at both ends in the axial direction inside the hub portion 325, respectively.

In the bearing housing portion 328 provided on the axle holding member 311 side, the bearing 16 is press-fitted at the most central side in the axial direction of the bearing housing portion 328, and the ring-shaped dust seal 30 is press-fitted outside the bearing 16 in the axle direction. Further, a ring-shaped labyrinth member 340 is disposed outside the dust seal 30. The bearing housing 328 is provided with a cylindrical collar 332 interposed between the bearing 16 and the labyrinth member 340. The collar 332 is provided through the dust seal 30.
A space portion 333 is formed between the bearing accommodating portions 327 and 328, and a tapered guide pipe 329 is disposed in the space portion 33.

The axle holding member 311 has an axle support hole 311C that penetrates in the vehicle width direction. The axle 312 is inserted into the axle support hole 311C from the inner side in the vehicle width direction, and the collar portion 312A at one end contacts the axle holding member 311. Fixed in the axial direction. The wheel 314 is connected to the axle 312 by a nut (not shown) that is fastened to the other end of the axle 312. By the fastening force of this nut, the inner race 15B, the guide pipe 329, the inner race 16B, and the collar 332 are The inner race 15 </ b> B, the guide pipe 29, the inner race 16 </ b> B, and the collar 332 are not allowed to rotate within the hub portion 325. The hub 320 rotates relative to the inner races 15B and 16B fixed to the axle 312 side together with the outer races 15A and 16A, so that the wheel 314 rotates relative to the axle 312 and the axle holding member 311.
A tightening margin is provided between the dust seal 30 and the collar 332 in the radial direction, and the lip portions 36 and 36 are deformed in accordance with the tightening allowance.

FIG. 8 is an enlarged cross-sectional view of the vicinity of the bearing housing portion 328.
As shown in FIGS. 7 and 8, the labyrinth member 340 is provided so as to close the axially open end 328 </ b> A of the bearing housing portion 328, and suppresses intrusion of water and dust into the bearing housing portion 328.
The labyrinth member 340 includes a cylindrical portion 344 that is formed in a cylindrical shape and protrudes into the bearing housing portion 328, and a plurality of fin portions 345A and 345B that extend radially outward from the outer peripheral surface 344A of the cylindrical portion 344. The fin portions 345A and 345B are hook-shaped convex portions extending along the circumferential direction of the outer peripheral surface 344A, and are formed so as to go around the outer peripheral surface 344A. The cylindrical portion 344 is a receiving portion that protrudes from the side wall portion 311 </ b> A in the vehicle width direction of the axle holding member 311 and is accommodated in the bearing accommodating portion 328.
The collar 332 is sandwiched between the inner race 16 </ b> B and the cylindrical portion 344, and a gap is provided between the cylindrical portion 344 and the dust seal 30.

A groove U having a width in the axial direction is formed between the fin portion 345A on the distal end side of the cylindrical portion 344 and the fin portion 345B located outside the fin portion 345A in the bearing housing portion 328. A groove V having a width in the axial direction is formed between the fin portion 345B and the side wall portion 311A. The lengths of the grooves U and V in the axial direction are substantially the same.
The heights of the fin portions 345A and 345B are formed substantially the same, and a gap W is formed in the radial direction between the tip of the fin portions 345A and 345B and the inner wall 328B of the bearing housing portion 328, and the fin portion 345A. , 345B does not contact the inner wall 328B. The size of the gap W is smaller than the lengths of the grooves U and V in the axial direction. As a result, water and dust can easily pass through the groove U and the groove V rather than the gap W, so that the entry of dust into the dust seal 30 can be suppressed.

In addition, a gap X is formed in the axial direction between the opening end 328A of the bearing housing portion 328 and the side wall portion 311A, and the side wall portion 311A does not contact the opening end 328A. The size of the gap X is smaller than the axial length of the grooves U and V, and the size of dust entering the grooves U and V from the gap X is smaller than the length of the grooves U and V. This dust becomes easy to fall through the grooves U and V. For this reason, intrusion of dust to the dust seal 30 side can be suppressed.
The labyrinth member 340 is configured by forming grooves U and V in the cylindrical portion 344 of the axle holding member 311 and is provided integrally with the axle holding member 311.

  The fin portion 345B is positioned on the outermost side in the axial direction among the plurality of fin portions 345A, 345B, and the drain portion 351 is formed at the lower portion of the fin portion 345B by notching the fin portion 345B and forming an opening. Is provided. In the lower part of the labyrinth member 340, the drainage part 351 is formed so that the groove U and the groove V communicate with each other. On the other hand, the notch is not formed in the fin portion 345A located on the innermost side.

  A drain hole 352 is formed in the lower portion of the side wall portion 311A of the axle holding member 311 by cutting out the side wall portion 311A adjacent to the water drain portion 351. The drainage portion 351 communicates with the lower outside of the axle holding member 311 by the drainage hole 352.

  As described above, according to the third embodiment to which the present invention is applied, the wheel 314 is supported on the axle 312 via the bearing 16 by the circular hub part 325, and the bearing housing part of the hub part 325 is supported. A dust seal 30 having a tightening margin is provided between the inner wall 328B of the 328 and the axle 312. A part of the dust seal 30 is accommodated within the width of the bearing accommodating portion 328, and a plurality of fin portions 345A and 345B extending radially outward from this portion. Since the labyrinth member 340 having the above is provided, it is possible to prevent the water and dust from entering the hub portion 325 by the labyrinth member 340, and it is possible to prevent water and dust from being applied to the bearing 16 without increasing the tightening force of the dust seal 30 caused by tightening. Intrusion can be suppressed. For this reason, the dust seal 30 can be provided between the axle 312 and the hub portion 325 so as not to increase the rotation loss of the wheel 314, and the fuel consumption of the vehicle 300 can be reduced. Furthermore, since the lower part of the outermost fin part 345B of the fin parts 345A and 345B of the labyrinth member 340 is cut out to form the water drain part 351, water and dust can be quickly discharged from the lower part of the fin parts 345A and 345B. While being able to discharge | emit, penetration | invasion of water and dust can be suppressed in 354A of inner sides from the outermost fin part 345B. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing 16.

The third embodiment shows one aspect to which the present invention is applied, and the present invention is not limited to the above-described embodiment.
In the third embodiment, the labyrinth member 340 is described as being provided integrally with the axle holding member 311. However, the present invention is not limited to this, and the labyrinth member 340 is formed as a separate member from the axle holding member 311. The axle shaft holding member 311 may be coupled.

[Fourth Embodiment]
Hereinafter, a fourth embodiment to which the present invention is applied will be described with reference to FIGS. 9 and 10. In the fourth embodiment, parts that are configured in the same manner as in the first embodiment are given the same reference numerals, and descriptions thereof are omitted.
In the fourth embodiment, the wheel support structure of the present invention is applied to an ATV (All Terrain Vehicle) which is a rough terrain vehicle, and the labyrinth member is provided on the wheel side in the first embodiment. It is different from the form.

FIG. 9 is a cross-sectional view showing the wheel support structure of the fourth embodiment.
The rough terrain vehicle 400 (hereinafter referred to as a vehicle) is a four-wheeled vehicle having wheels on the front, rear, left and right sides of the vehicle body, and FIG. It is.
The wheel support structure of the vehicle 400 includes an axle holding member 411 provided on the vehicle body side, and a front wheel 410 that is pivotally supported by the axle holding member 411.

The front wheel 410 is configured by assembling a tire (not shown) to the wheel 414, and the wheel 414 is provided by integrally connecting a rim (not shown) to which the tire is assembled to the hub 420. The wheel 414 is pivotally supported by the axle holding member 411 via a bearing 416 provided on the axle holding member 411.
The axle holding member 411 has a cylindrical bearing housing portion 428 (shaft support portion) extending in the vehicle width direction, and a bearing 416 is press-fitted into the inner end of the bearing housing portion 428 in the vehicle width direction. A dust seal 30 is press-fitted outside the bearing 416 in the bearing housing 428, and a clip 415 that engages the bearing 416 in the axial direction is engaged between the dust seal 30 and the bearing 416.
A knuckle 405 for turning the axle holding member 411 is connected to the lower portion of the axle holding member 411.

The hub 420 includes a hub portion 425 that serves as a rotation center of the wheel 414, a shaft portion 412 that extends from the hub portion 425 in the vehicle width direction, and a rim coupling portion 426 that extends from the hub portion 425 in the radial direction.
The shaft portion 412 is formed in a stepped shape that becomes narrower toward the tip, and is connected to the inner peripheral surface of the inner race 416B of the bearing 416 on the tip side, and is formed to have a larger diameter than the connection shaft portion 406 and dust seal. 30 and a labyrinth portion 440 that is formed to have a larger diameter than the seal portion 407 and closes the opening end 428A of the bearing accommodating portion 428.

The wheel 414 rotates with respect to the axle holding member 411 by rotating the hub 420 together with the inner race 416B via the ball 416C with respect to the outer race 416A fixed to the bearing housing portion 428.
A tightening margin is provided between the dust seal 30 and the seal portion 407 in the radial direction, and the lip portions 36 and 36 are deformed according to the tightening allowance. When the wheel 414 rotates, the seal portion 407 rotates relative to the dust seal 30, and friction is generated according to the tightening allowance.

FIG. 10 is an enlarged cross-sectional view of the vicinity of the bearing housing portion 428.
As shown in FIGS. 9 and 10, the labyrinth portion 440 has a plurality of fin portions 445A, 445B, and 445C that extend radially outward from the outer peripheral surface 412A of the shaft portion 412 accommodated within the width of the bearing accommodating portion 428. is doing. The fin portions 445A, 445B, and 445C are hook-shaped convex portions that extend along the circumferential direction of the shaft portion 412 and are formed so as to go around the outer peripheral surface 412A. The labyrinth part 440 is a accommodated part accommodated in the bearing accommodating part 428. The labyrinth portion 440 is formed integrally with the shaft portion 412.

A groove E having a width in the axial direction is formed between the fin portion 445A closest to the dust seal 30 and the central fin portion 445B, and a width in the axial direction is formed between the fin portion 445B and the outermost fin portion 445C. A groove F having The lengths of the grooves E and F in the axial direction are substantially equal.
The heights of the fin portions 445A, 445B, 445C are substantially the same, and a gap G is formed in the radial direction between the tip of the fin portions 445A, 445B, 445C and the inner wall 428B of the bearing housing portion 428. The fin portions 445A, 445B, and 445C do not contact the inner wall 428B.

  The size of the gap G in the radial direction is smaller than the length of the grooves E and F in the axial direction. As described above, by providing the fin portion 445C having the gap G smaller than the length of the grooves E and F on the inner side of the opening end 428A, intrusion of water and dust into the labyrinth portion 440 can be suppressed, and the grooves E and F Even if water or dust enters the water, it is easier for water and dust to pass through the grooves E and F than through the gap G between the fin portions 445A and 445B, so that water and dust can enter the dust seal 30 and the bearing 416 side. Can be suppressed.

  In addition, a gap H is formed in the axial direction between the opening end 428A of the bearing accommodating portion 428 and the side wall portion 420A of the hub 420, and the side wall portion 420A does not contact the opening end 428A. The size of the gap H is smaller than the axial length of the grooves E and F, and the size of dust entering the grooves E and F from the gap H is larger than the length of the grooves E and F. This dust becomes easy to fall through the grooves E and F. For this reason, intrusion of dust to the dust seal 30 side can be suppressed.

  A drainage portion 451 is formed by cutting out the inner wall 428B of the bearing accommodating portion 428 at a portion facing the grooves E and F and the fin portion 445B below the opening end 428A of the bearing accommodating portion 428. In the drainage portion 451, the gap between the labyrinth portion 440 and the inner wall 428B is large, and water and dust can be efficiently discharged from this gap. On the other hand, the drainage portion 451 is not formed in the portion of the inner wall 428B facing the fin portion 445A on the innermost side in the axial direction, and the gap G is secured over the entire circumference.

Further, a drain hole 452 is formed in a portion adjacent to the drainage portion 451 below the opening end 428A by cutting out the opening end 428A in the axial direction. In the drain hole 452, the gap between the opening end 428 </ b> A and the side wall part 420 </ b> A is large, so that water and dust in the drain part 451 can be efficiently discharged to the outside through the gap of the drain hole 452. Furthermore, since the rim connecting portion 426 is provided on the side of the drain hole 452, it is possible to prevent water and dust from entering the drain hole 452 from the side.
Further, in the configuration in which the labyrinth portion 440 is provided on the rotating shaft portion 412, if the drainage portion is provided in the labyrinth portion 440 portion, the drainage portion also rotates together with the labyrinth portion 440, and the drainage portion is positioned below. However, as described above, by providing the drainage portion 451 in the bearing accommodating portion 428 that does not rotate, the drainage portion 451 can be formed in the lower portion, so that water and dust can be discharged efficiently.

  As described above, according to the fourth embodiment to which the present invention is applied, the wheel 414 is pivotally supported on the vehicle body side via the bearing 416 by the cylindrical bearing housing portion 428 provided on the vehicle body side, A dust seal 30 having a tightening margin is provided between the inner wall 428B of the bearing housing portion 428 and the hub portion 425. The dust seal 30 is housed within the width of the bearing housing portion 428, and a plurality of fins extending radially outward from the housing portion. Since the labyrinth portion 440 having the portions 445A, 445B, and 445C is provided, the labyrinth portion 440 can prevent water and dust from entering the hub portion 425 side, and the bearing can be provided without increasing the tightening force of the dust seal 30 caused by tightening allowance. Intrusion of water and dust into 416 can be suppressed. For this reason, the dust seal 30 can be provided between the hub portion 425 and the bearing accommodating portion 428 so as not to increase the rotation loss of the wheel 414, and the fuel consumption of the vehicle 400 can be reduced. Further, in the lower part of the bearing housing portion 428, the portions near the axially outer fin portions 445B, 445C among the plurality of fin portions 445A, 445B, 445C are cut out to form the drainage portion 451. Water and dust can be quickly discharged from the lower portion of the portion 428, and entry of water and dust can be suppressed by the inner fin portion 445A. For this reason, it is possible to prevent water and dust from affecting the performance of the bearing 416.

In addition, the said 4th Embodiment shows the one aspect | mode which applied this invention, Comprising: This invention is not limited to the said embodiment.
In the fourth embodiment, the labyrinth portion 440 has been described as being formed integrally with the shaft portion 412. However, the present invention is not limited to this, and for example, the labyrinth is a member separate from the shaft portion 412. It is good also as a structure which forms a part and equips this axial part 412 with this labyrinth part.

1 Motorcycle (vehicle)
11 Front fork (axle holding member)
12,312 Axle 12A Shaft 14,314 Wheel 16 Bearing 17 Anti-rotation 25,325 Hub 28A Open end (Axial outer end)
28B, 328B Inner wall 30 Dust seal (seal member)
32 Collar member 34 Locking concave part 40, 240, 340 Labyrinth member 41B Locking convex part 43 Outer cover part 45A, 45B, 245C, 345A, 345B Fin part 49 Locking part 50 Side bulging part 51, 252, 351 Water Drain part 52 Drain hole 300,400 Vehicle 311 Axle holding member 412 Shaft part 414 Wheel 416 Bearing 425 Hub part 428 Bearing housing part (shaft support part)
428B Inner wall 440 Labyrinth part 445A, 445B, 445C Fin part 451 Drain part P, T, U Groove (groove between fin parts)
Q, W clearance (radial clearance)
R and X clearances (clearances with axially outer edges)

Claims (9)

An axle (12, 312) fixed to the vehicle body side and a wheel (14, 314) pivotally supported by the axle (12, 312) are provided, and the wheel (14, 314) is the axle (12, 312). ), And the wheel (14, 314) is connected to the axle (12) via the bearing (16) at the hub (25, 325). 312) is provided on the outer side in the axial direction of the bearing (16), and is tightened between the inner wall (28B, 328B) of the hub portion (25, 325) and the axle (12, 312). In the vehicle wheel support structure provided with the seal member (30) having a margin,
A plurality of fin portions (45A, 45B, 45A, 45B,..., Which are partially accommodated within the width of the hub portion (25, 325) on the outer side in the axial direction of the seal member (30), Labyrinth members (40, 240, 340) having 245C, 345A, 345B) are provided,
Of the plurality of fin portions (45A, 45B, 245C, 345A, 345B), a lower portion of the outermost fin portion is cut out to form a drainage portion (51, 252, 351). Wheel support structure.   The fin portion (45A, 45B, 245C, 345A, 345B) of the labyrinth member (40, 240, 340) and the inner wall (28B, 328B) of the hub portion (25, 325) of the wheel (14, 314) The radial gap (Q, W) is provided smaller than the grooves (P, T, U) between the plurality of fins (45A, 45B, 245C, 345A, 345B). A wheel support structure for a vehicle according to claim 1.   An outer cover portion (43) positioned axially outside the hub portion (25) is provided outside the labyrinth member (40) with respect to the wheel center, and the outer cover portion (43) and the hub are provided. The gap between the axially outer end (28A) of the portion (25) is provided smaller than the groove (P) between the plurality of fin portions (45A, 45B). Vehicle wheel support structure.   The vehicle includes an axle holding member (11) that holds the axle (12), and an engaging portion (49) is provided on the outer cover portion (43) of the labyrinth member (40), so that the axle holding is performed. The wheel support structure for a vehicle according to claim 3, wherein the member (11) is provided with a rotation preventing portion (17) for locking the locking portion (49).   A drain hole (52) of the labyrinth member (40) is provided in the outer cover part (43), and a side bulge part (50) covering the side of the drain hole (52) The wheel support structure for a vehicle according to claim 3 or 4, wherein the wheel support structure is provided on the cover (43).   The area of the drain hole (52) is larger than the cross-sectional area of the groove (P) between the plurality of fins (45A, 45B) of the labyrinth member (40). Item 6. A vehicle wheel support structure according to Item 5.   Of the plurality of fins (45A, 45B, 245C), two or more outermost cutouts are provided with lower notches, and the inside fins of the plurality of fins (45A, 45B, 245C) The vehicle wheel support structure according to claim 6, wherein a gap between the hub portion and the hub portion is made constant.   The axle (12) has a collar member (32) disposed adjacent to the outside of the bearing (16), and the collar member (32) has a locking recess (34) along the circumferential direction. The vehicle wheel support structure according to claim 1, wherein the labyrinth member (40) is provided with a locking projection (41B) that is locked to the locking recess (34). A tubular shaft support portion (428) provided on the vehicle body side and a wheel (414) pivotally supported by the shaft support portion (428) are provided, and the hub portion (425) of the wheel (414) has the shaft A shaft portion (412) extending along the support portion (428) is provided. The shaft portion (412) is pivotally supported by the shaft support portion (428) via a bearing (416), and the bearing (416) ) And a seal member (30) having a tightening margin between an inner wall (428B) of the shaft support portion (428) and the hub portion (425). In
A plurality of fin portions (445A, 445B, 445C) are accommodated within the width of the shaft support portion (428) and extend radially outward from the accommodated portion outside the seal member (30) in the axial direction. Labyrinth part (440) is provided,
In the lower part of the shaft support portion (428), a portion of the plurality of fin portions (445A, 445B, 445C) in the vicinity of the fin portion on the outer side in the axial direction is cut out to be a drainage portion (451). A vehicle wheel support structure.

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