JP2009079630A - Wheel support device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wheel support device in which a creep is hardly generated at a bearing. <P>SOLUTION: Semicircular shaped recessed parts 17, 18 are formed on the divided surface 8b of an inner ring piece 8 at a vehicle outer side and the divided surface 9a of an inner ring piece 9 at a vehicle inner side in a bearing 4, and projections 22 fitted to the recessed parts 17, 18 are formed on the inner peripheral surface of an intermediate member 19 mounted astride both inner ring pieces 8, 9. When the creep is generated and the inner ring piece 9 at the vehicle inner side turns around the axis 1a of the axle shaft 1 out of both the inner ring pieces 8, 9 fitted and mounted to the axle shaft 1 through the intermediate member 19, the turning is restrained by the inner ring piece 8 at the vehicle outer side connected through the projections 22 of the intermediate member 19 engaged with the recessed parts 17, 18. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a vehicle wheel support device.

  As an axle structure used on the drive wheel side of a vehicle (for example, an automobile), there is one called a “half-floating type wheel support device” (see Patent Document 1). Since this type of wheel support device is lightweight, it is often used for small vehicles such as passenger cars. In the semi-floating type wheel support device, an axle shaft having a wheel attachment portion at an end is accommodated in an axle housing via a bearing. The power is transmitted to the wheel by the axle shaft.

  The bearings of the semi-floating wheel support device are pressed against the outer peripheral surface of the axle shaft to prevent rotation. However, since the semi-floating type wheel support device has no axial force due to its structure, creep is likely to occur in the bearing even if the turning gravity is low. Here, the creep in the bearing means, “In the case of rotational load, when a clearance is generated in the fitting surface between the raceway surface of the inner ring piece and the outer peripheral surface of the axle shaft, the inner surface of the fitting surface is in relation to the outer surface. "Phenomenon that relatively shifts in the direction opposite to the rotational direction of the inner ring piece rotational load (in a broad sense, includes a case where the driving side slips in the driving direction relative to the other side on the fitting surface regardless of the rotational direction)". As a result, the raceway surface of the bearing may be peeled off, or abnormal noise or vibration may occur.

Further, in recent vehicles, the anti-lock brake is used to detect the rotational speed of the wheel by a sensor (for example, an encoder) attached to the inner ring piece of the bearing. If creep occurs in the bearing, the detection accuracy of the rotational speed of the wheel may be reduced.
JP-A-4-113902

  In view of the above-described problems, an object of the present invention is to provide a wheel support device in which creep is unlikely to occur in a bearing.

Means for Solving the Problems and Effects of the Invention

The present invention for achieving the above-mentioned problems
In order to support the axle shaft for transmitting the driving force to the wheel attached to the front end portion of the vehicle outer side with the axle housing, the mounting flange portion fixed to the axle housing, the mounting flange portion, A semi-floating wheel support device comprising a bearing unit including a double row bearing interposed between an axle shaft and
The inner ring of the bearing is divided into an inner ring piece on the vehicle outer side and an inner ring piece on the vehicle inner side at an intermediate position in the axial direction, and a split surface of the inner ring piece on the vehicle inner side and the vehicle outer side are arranged to face each other. When the inner ring piece on the vehicle outer side and the inner ring piece on the vehicle inner side are combined in a predetermined positional relationship and integrated with the split surface of the inner ring piece, both inner ring pieces are directly or indirectly via other members. The engaging portions for engaging with each are formed,
When the inner ring pieces are engaged with each other, the generation of creep between the inner ring piece on the vehicle inner side and the axle shaft is suppressed by the inner ring piece on the vehicle outer side.

  The wheel support device according to the present invention is configured as described above, and the inner ring piece on the vehicle outer side and the inner ring piece on the vehicle inner side are directly or indirectly engaged. For this reason, even if a large load acts on the inner ring to cause creep and the inner ring piece on the vehicle inner side tries to rotate with respect to the axle shaft, the inner ring piece on the vehicle outer side is restrained. As a result, the occurrence of creep between the inner ring of the bearing and the axle shaft is prevented.

When both inner ring pieces are indirectly engaged through other members,
A ring-shaped intermediate member disposed across the inner ring piece on the vehicle outer side and the inner ring piece on the vehicle inner side;
Projections are formed on the inner peripheral surface of the intermediate member to engage with the engaging portions of the inner ring pieces, while the engaging portions of the inner ring pieces are engaged with the protruding portions. Each of the divided surfaces may be formed as a recess.

  The other member that indirectly engages both inner ring pieces is a ring-shaped intermediate member, and the protrusion formed on the inner peripheral surface thereof is engaged with the recesses of both inner ring pieces. Is easy, and interference with other members of the bearing is avoided.

And, in a state where the split surfaces of the inner ring pieces are arranged to face each other, the concave portion of one inner ring piece is arranged to face the surface in which the concave portion in the divided surface of the other inner ring piece is not formed,
A plurality of projecting portions of the intermediate member may be provided so as to fit into the respective recesses of the inner ring piece.

  Since many protrusions of the intermediate member can be provided, the engagement between the intermediate member and both inner ring pieces can be ensured.

  Furthermore, the intermediate member may be provided with a locking portion that is locked with the inner ring piece when the intermediate member is disposed across the both inner ring pieces.

  When the latching | locking part provided in the intermediate member and both the inner ring pieces latch, it is prevented that both the inner ring pieces isolate | separate.

When both inner ring pieces are directly engaged,
The engaging portion of the one inner ring piece is a convex portion formed so as to protrude in the axial direction over a half circumference from the divided surface,
The engagement portion of the other inner ring piece may be a recess formed by being recessed in the axial direction over a half circumference from the split surface.

  Since both inner ring pieces are directly engaged, an intermediate member is not required, and the configuration is simple.

  Whether the inner ring pieces are directly engaged or indirectly engaged, the width of the inner ring piece on the vehicle inner side is equal to the width of the inner ring piece on the vehicle outer side. It is desirable to be larger than.

  As a result, the contact area between the inner ring piece on the vehicle inner side and the axle shaft, which is particularly prone to creep, can be increased, so that creep can be further prevented.

  Examples of the present invention will be described. FIG. 1 is a front sectional view of a wheel support device 101 according to a first embodiment of the present invention, FIG. 2 (a) is a front half sectional view of both inner ring pieces 8, 9 and an intermediate member 19, and FIG. -X-ray sectional view, FIG. 3 is a plan view showing a state in which the inner ring pieces 8 and 9 and the intermediate member 19 are separated.

  A wheel support device 101 according to a first embodiment of the present invention will be described. As shown in FIG. 1, the wheel support device 101 of the first embodiment includes an axle shaft 2 for transmitting a driving force to a wheel (not shown) attached to a front end portion on the vehicle outer side. The bearing unit 200 includes a mounting flange portion 3 fixed to the axle housing 2 and a double row bearing 4 interposed between the mounting flange portion 3 and the axle shaft 1. I have. The front end portion of the axle shaft 1 on the vehicle outer side extends toward the outside in the radial direction, and a wheel mounting portion is provided in the extended portion. In the wheel support device 101 of the present embodiment, the conical washer 5 and the retainer ring 6 are fitted in this order on the vehicle inner side of the bearing 4 mounted on the axle shaft 1. The retainer ring 6 is press-fitted into the axle shaft 1 in a state where the conical washer 5 is crushed in the axial direction to be compressed and deformed. The retainer ring 6 is held immovably in the axial direction by a snap ring 7 fitted to the axle shaft 1.

  The bearing 4 will be described. As shown in FIGS. 1 and 2, the bearing 4 of the wheel support device 101 of this embodiment is a double-row angular ball bearing, and is press-fitted into the outer peripheral surface of the axle shaft 1 so as to be integrated with the axle shaft 1. An inner ring to be rotated (an inner ring piece 8 on the vehicle outer side and an inner ring piece 9 on the vehicle inner side), an outer ring 11 fixed to the axle housing 2 via the mounting flange 3, and a pair of inner ring pieces 8, 9 A plurality of rolling elements (balls 12) interposed between the outer ring 11 and the outer ring 11 are provided. The inner ring is an intermediate portion in the axial direction and is divided into an inner ring piece 8 on the vehicle outer side and an inner ring piece 9 on the vehicle inner side. In the case of the wheel support device 101 of the first embodiment, the width L2 (length in the axial direction) of the inner ring piece 9 on the vehicle inner side is larger than the width L1 (length in the axial direction) of the inner ring piece 8 on the vehicle outer side. Is longer (L1 <L2). Both inner ring pieces 8 and 9 are composed of a large-diameter portion and a small-diameter portion that are joined in a continuous state, and inner ring raceway surfaces 13 and 14 for rolling the balls 12 are provided at the joint portions of both. An end surface 8 a (end surface on the vehicle outer side) of the inner ring piece 8 on the large diameter portion side is in contact with a lower end portion of the wheel mounting portion of the axle shaft 1. Further, the end faces 8b, 9a on the small diameter side of the inner ring pieces 8, 9 are opposed to each other in a state of being butted and joined. Similarly, an outer ring raceway surface 15 is formed on the inner peripheral surface of the outer ring 11. The plurality of balls 11 are held by a cage 16.

  As shown in FIGS. 2 and 3, semicircular recesses 17 and 18 are provided on the end surfaces (divided surfaces 8 b and 9 a) on the small diameter side of both inner ring pieces 8 and 9, and the axis 1 a of the axle shaft 1 is connected to the inner ring pieces 8 and 9. It is provided at a symmetrical position with the center. When the end surfaces 8b and 9a of the small diameter part of both the inner ring pieces 8 and 9 are joined, the semicircular recesses 17 and 18 are combined into a circular shape.

  An intermediate member 19 is disposed at the joint between the inner ring pieces 8 and 9. The intermediate member 19 has a ring-shaped main body portion 21 and a pair of projecting portions 22 projecting inward in the radial direction from the inner peripheral surface thereof. The pair of protrusions 22 are provided at symmetrical positions with the axis 1 a of the axle shaft 1 as the center. The protrusion 22 has a cylindrical shape, and its radius of curvature is slightly smaller than the radius of curvature of the recesses 17 and 18 of the inner ring pieces 8 and 9. For this reason, the protrusion part 22 can be fitted to the recessed parts 17 and 18 which were united and became circular shape.

  In the wheel support device 101 of the first embodiment, the operation when the inner ring pieces 8 and 9 are assembled will be described. Both inner ring pieces 8 and 9 are assembled to the axle shaft 1. At this time, the intermediate member 19 is disposed between the inner ring pieces 8 and 9 in advance, and the inner ring pieces 8 and 9 and the intermediate member 19 are integrally fitted to the axle shaft 1. Both inner ring pieces 8 and 9 are fitted and mounted at predetermined positions on the axle shaft 1 in a state in which the divided surfaces 8 b and 9 a are joined via the intermediate member 19. Thereby, while the intermediate member 19 is arrange | positioned ranging over the junction part of both the inner ring pieces 8 and 9, and each protrusion part 22 was fitted by the recessed parts 17 and 18 of the corresponding inner ring pieces 8 and 9, and Become. Since the protrusions 22 of the intermediate member 19 are fitted in the recesses 17 and 18 of the inner ring pieces 8 and 9, the inner ring pieces 8 and 9 are rotated around the axis 1 a of the axle shaft 1 during press-fitting. It is not.

  Next, the operation of the wheel support device 101 of the first embodiment when the vehicle is traveling will be described. A large load acts on the bearing 4 when the vehicle travels (for example, when the vehicle turns). The magnitude of the load at this time is much larger in the inner ring piece 9 on the vehicle inner side than in the inner ring piece 8 on the vehicle outer side. As a result, creep easily occurs particularly between the inner ring piece 9 on the vehicle inner side and the axle shaft 1. In order to prevent this problem, the axial force (elastic restoring force) of the conical washer 5 is applied to the inner ring piece 9 on the vehicle inner side. Further, by making the width L2 of the inner ring piece 9 on the vehicle inner side longer than the width L1 of the inner ring piece 8 on the vehicle outer side, the contact area between the inner ring piece 9 and the outer peripheral surface of the axle shaft 1 is increased. However, the inner ring piece 9 on the vehicle inner side is less likely to be creeped.

  In the case of the wheel support device 101 according to the first embodiment, the intermediate member 19 is attached between the inner ring pieces 8 and 9, and the protrusions 22 of the intermediate member 19 are formed in the recesses 17 of the corresponding inner ring pieces 8 and 9. , 18 are engaged. If creep occurs between the inner ring piece 9 on the vehicle inner side and the axle shaft 1 (in other words, the inner ring piece 9 on the vehicle inner side tries to rotate around the axis 1a of the axle shaft 1). The inner ring piece 9 on the vehicle inner side tries to rotate the intermediate member 19 in the same direction via the protrusion 22 engaged with the recess 18. However, the protrusion 22 of the intermediate member 19 is also engaged with the recess 17 of the inner ring piece 8 on the vehicle outer side. Here, as described above, since the load acting on the inner ring piece 8 on the vehicle outer side is small, the possibility that creep will occur between the inner ring piece 8 on the vehicle outer side and the axle shaft 1 is extremely small. Therefore, when the inner ring piece 9 on the vehicle inner side is about to rotate, the protrusion 22 of the intermediate member 19 engaged with the inner ring piece 8 on the vehicle outer side is rotated by the inner ring piece 9 on the vehicle inner side. It will serve as a brake to deter movement. Thereby, the inner ring piece 9 on the vehicle inner side is also difficult to rotate, and the occurrence of creep between the inner ring piece 9 on the vehicle inner side and the axle shaft 1 is prevented.

  Then, as shown in FIGS. 4A and 4B, a pair of claw portions 23 are projected on the inner peripheral surface of the main body portion 21 of the intermediate member 19, and the small diameter portions of the inner ring pieces 8 and 9 are formed. You may provide the separation prevention recessed part 24 in which the nail | claw part 23 is latched in an outer peripheral surface. When the intermediate member 19 is mounted across the split surfaces 8b and 9a of the inner ring pieces 8 and 9, the claw portions 23 are fitted into the separation preventing recesses 24 of the corresponding inner ring pieces 8 and 9 while being elastically deformed. Is done. Thereby, since both the inner ring pieces 8 and 9 and the intermediate member 19 are latched, it is prevented that both the inner ring pieces 8 and 9 isolate | separate. As a result, the assembling work is further facilitated, and the rotation of the inner ring piece 9 on the vehicle inner side is also suppressed by the claw portions 23.

  As described above, in the wheel support device 101 of the first embodiment, not only the axial force of the conical washer 5 but also the inner ring piece 8 on the vehicle outer side connected via the intermediate member 19, the inner ring on the vehicle inner side is used. The occurrence of creep between the piece 9 and the axle shaft 1 is prevented. For this reason, creep is less likely to occur in the bearing 4, and damage such as peeling of the inner ring raceway surfaces 13 and 14 of the bearing 4 and generation of abnormal noise and vibration are prevented.

  The inner ring pieces 8 and 9 in the above-described embodiment are cases where the semicircular recesses 17 and 18 are circular when they are joined. Accordingly, there is an advantage that only one protrusion 22 of the intermediate member 19 is required for each of the recesses 17 and 18. However, as shown in FIGS. 5A and 5B, the protruding portion 25 of the intermediate member 19 may be provided for the concave portions 17 and 18, respectively.

  In the above-described embodiment, the same number of the concave portions 17 and 18 of the inner ring pieces 8 and 9 and the protruding portions 22 and 25 of the intermediate member 19 are provided. However, the number of the concave portions 17 and 18 of both the inner ring pieces 8 and 9 can be formed larger than the number of the protruding portions 22 and 25 of the intermediate member 19. Thereby, the operation | work which arrange | positions both the inner ring pieces 8 and 9 to the intermediate member 19 becomes still easier.

  Next, the wheel support apparatus 102 of 2nd Example is demonstrated. Whereas the wheel support device 101 of the first embodiment indirectly engages the inner ring pieces 8 and 9 via the intermediate member 19, the wheel support device 102 of the second embodiment This is a case where both inner ring pieces 26 and 27 are directly engaged. As shown in FIG. 6, in the case of the wheel support device 102 of the second embodiment, the split surfaces of the inner ring piece 26 on the vehicle outer side and the inner ring piece 27 on the vehicle inner side are the upper half and lower half of the axle shaft 1. It is shifted in the axial direction. That is, as shown in FIG. 7, convex portions 26a and 27a are provided on the divided surfaces of both inner ring pieces 26 and 27 over a half circumference, respectively. The inner ring pieces 26 and 27 are joined with their circumferential phases shifted by 180 °. Thereby, the convex parts 26a and 27a in the division surface of both the inner ring pieces 26 and 27 are connected in an engaged state. As a result, similar to the wheel support device 101 of the first embodiment, even if creep occurs between the inner ring piece 27 on the vehicle inner side and the axle shaft 1 and the inner ring piece 27 tries to rotate, the vehicle outer side The inner ring piece 26 prevents the rotation. Even in this embodiment, it is desirable to make the width L2 of the inner ring piece 27 on the vehicle inner side longer than the width L1 of the inner ring piece 26 on the vehicle outer side.

  It should be noted that the inner ring piece 8 on the vehicle outer side and the inner ring piece 9 on the vehicle inner side are not engaged (in other words, the engaging portions are not provided on the inner ring pieces 8, 9). It is good also as a wheel support device which changed only width L1, L2 (L1 <L2) of 9. The wheel support device in this state is shown in FIG. 8 as a reference example.

It is front sectional drawing of the wheel support apparatus 101 of 1st Example of this invention. (A) is a front half sectional view of both inner ring pieces 8, 9 and the intermediate member 19, and (b) is a sectional view taken along the line XX. FIG. 3 is a plan view showing a state where both inner ring pieces 8 and 9 and an intermediate member 19 are separated. (A), (b) is operation | movement explanatory drawing of the state in which the nail | claw part 23 of the intermediate member 19 is latched by the separation prevention recessed part 24 of both the inner ring pieces 8 and 9. FIG. (A), (b) is a top view in case the protrusion part 25 of the intermediate member 19 is provided with respect to the recessed parts 17 and 18 of both the inner ring pieces 8 and 9, respectively. It is front sectional drawing of the wheel support apparatus 102 of 2nd Example. (A) is front sectional drawing of both the inner ring | wheel pieces 26 and 27, (b), (c) is the Y1-Y1 sectional view taken on the line of (a), respectively, and the Y2-Y2 sectional view. It is front sectional drawing of the wheel support apparatus which changed only width L1, L2 of both the inner ring pieces 8,9.

Explanation of symbols

101, 102 Wheel support device 200 Bearing unit 1 Axle shaft 2 Axle housing 3 Mounting flange 4 Bearing 8, 26 Inner ring piece (inner ring piece on the vehicle outer side)
9, 27 Inner ring piece (inner ring piece on the vehicle inner side)
8b, 9a End face (divided face)
17, 18 Recess (engagement part)
19 Intermediate members 22, 25 Protruding part (engaging part)
26a, 27a Convex part

Claims (6)

In order to support the axle shaft for transmitting the driving force to the wheel attached to the front end portion of the vehicle outer side with the axle housing, the mounting flange portion fixed to the axle housing, the mounting flange portion, A semi-floating wheel support device comprising a bearing unit including a double row bearing interposed between an axle shaft and
The inner ring of the bearing is divided into an inner ring piece on the vehicle outer side and an inner ring piece on the vehicle inner side at an intermediate position in the axial direction. When the inner ring piece on the vehicle outer side and the inner ring piece on the vehicle inner side are combined in a predetermined positional relationship and integrated with the split surface of the inner ring piece, both inner ring pieces are directly or indirectly via other members. The engaging portions for engaging with each are formed,
The wheel support device is characterized in that when the inner ring pieces are engaged with each other, the generation of creep between the inner ring piece on the vehicle inner side and the axle shaft is suppressed by the inner ring piece on the vehicle outer side. . A ring-shaped intermediate member disposed across the inner ring piece on the vehicle outer side and the inner ring piece on the vehicle inner side;
On the inner peripheral surface of the intermediate member, protrusions that are engaged with the engaging portions of the inner ring pieces are formed, respectively, while the engaging portions of the inner ring pieces are engaged with the protruding portions. The wheel support device according to claim 1, wherein each of the divided surfaces is formed as a recess. In a state in which the split surfaces of the inner ring pieces are arranged to face each other, the concave portion of one inner ring piece is arranged to face the surface of the other inner ring piece on which the concave portion is not formed,
3. The wheel support device according to claim 2, wherein a plurality of protrusions of the intermediate member are provided so as to fit into the respective recesses of the inner ring piece.   4. The wheel support according to claim 2, wherein the intermediate member is provided with a locking portion that is locked with the inner ring piece when the intermediate member is disposed across the two inner ring pieces. 5. apparatus. The engaging portion of the one inner ring piece is a convex portion that is formed to protrude in the axial direction over a half circumference from the divided surface,
2. The wheel support device according to claim 1, wherein the engaging portion of the other inner ring piece is a recessed portion that is recessed in the axial direction over a half circumference from the split surface.   The wheel support device according to any one of claims 1 to 5, wherein a width of the inner ring piece on the vehicle inner side is larger than a width of the inner ring piece on the vehicle outer side.

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