JP6019554B2 - Wheel bearing - Google Patents

Description

  The present invention is provided between a vehicle body side member provided so as to be swingable with respect to the vehicle body and a wheel side member provided so as to be rotatable integrally with the wheel, and the wheel side member is rotatably supported with respect to the vehicle body side member. The present invention relates to a wheel bearing.

Conventionally, in a wheel bearing that is fitted to an output shaft of an in-wheel motor that is a rotational drive source and rotatably supports a hub that rotates integrally with the wheel, an outer member of the wheel bearing using a displacement sensor There is known a wheel bearing for measuring the distance between the inner member and the inner member (for example, see Patent Document 1).
In this wheel bearing, the external force acting on the wheel bearing is estimated according to the distance between the outer member and the inner member.

JP 2008-75789 A

  However, in the conventional wheel bearing, a very small gap distance must be detected by a displacement sensor. For example, a high-precision sensor capable of detecting a distance of about 10 μm is necessary, and the sensor is also attached. High accuracy was required. Therefore, there is a problem that the manufacturing cost increases and the cost increases.

  The present invention has been made paying attention to the above-described problem, and an object thereof is to provide a wheel bearing capable of detecting a relative displacement between an outer member and an inner member with an inexpensive structure. .

In order to achieve the above object, in the wheel bearing according to the present invention, the wheel bearing is provided between a vehicle body side member provided so as to be swingable with respect to the vehicle body and a wheel side member provided so as to be integrally rotatable with the wheel. A wheel bearing that rotatably supports the member with respect to the vehicle body side member is assumed, and includes an outer member, an inner member, and a facing surface portion.
The outer member is fixed to the vehicle body side member, and has an outer rolling surface in contact with the rolling element on the outer surface.
The inner member is fixed to the wheel side member, and has an inner rolling surface in contact with the rolling element on an outer surface facing the outer member.
The opposed surface portions are provided on the outer member and the inner member, face each other with a predetermined gap therebetween, and wrap in the axial direction.

In the wheel bearing of the present invention, the opposing surface portions provided on the outer member and the inner member are opposed to each other with a predetermined interval, and the outer member and the inner member are wrapped in the axial direction. When the relative position is shifted by the predetermined gap, the opposed surface portions interfere with each other.
Then, abnormal noise occurs due to interference between the opposing surface portions, and the user is notified of the abnormality without using a sensor before the positional deviation between the outer member and the inner member becomes larger than the predetermined gap. Can do.
That is, since the opposed surface portions face each other with a predetermined interval and are wrapped in the axial direction, when the rolling element sandwiched between the outer member and the inner member is reduced in diameter by wear, the shaft of the outer member On the other hand, the whirling caused by the relative eccentricity of the shaft of the inner member and the positional deviation in the axial direction can be detected as abnormal noise generated positively and intentionally.
As a result, it is possible to detect the occurrence of relative positional deviation between the outer member and the inner member with an inexpensive structure.

It is a vertical side view which shows the in-wheel motor unit to which the wheel bearing of Example 1 was applied. It is the vertical side view which expanded the principal part of the in-wheel motor unit shown in FIG. It is the A section enlarged view in FIG. It is the B section enlarged view in FIG. It is the C section enlarged view in FIG. In the wheel bearing of Example 1, it is a principal part enlarged view when position shift arises along an axial direction. In the wheel bearing of Example 1, it is a principal part enlarged view when position shift arises along the axial direction. In the wheel bearing of Example 1, it is a principal part enlarged view when position shift arises along the inclination direction with respect to an axial direction. It is a principal part enlarged view which shows the other example of the wheel bearing of Example 1. FIG. FIG. 6 is an enlarged view of a main part showing still another example of the wheel bearing of the first embodiment.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the wheel bearing of this invention is demonstrated based on Example 1 shown on drawing.

  First, the configuration of the shaft coupling according to the present invention will be described by dividing it into “configuration of application example of wheel bearing” and “configuration of wheel bearing”.

[Configuration of application example of wheel bearing]
FIG. 1 is a longitudinal side view showing an in-wheel motor unit to which the wheel bearing of the first embodiment is applied. FIG. 2 is an enlarged vertical side view of the main part of the in-wheel motor unit shown in FIG.

  The hub bearing 40 of the first embodiment, which is a wheel bearing, is applied to the in-wheel motor unit MU shown in FIG. The in-wheel motor unit MU shown in FIG. 1 includes an electric motor 10 that drives a wheel 30 arranged inside a wheel 31 that supports the wheel 30, and includes a case 1, an electric motor 10, and a speed reducer 20. And have.

  The case 1 includes a motor side case portion 2 on the left side in FIG. 1, a reducer side case portion 3 in the center, and an output shaft side case portion (vehicle body side member) 4 on the right side in FIG. Configure. In this case 1, an electric motor 10 serving as a rotational drive source and a speed reducer 20 that decelerates and outputs the rotation of the electric motor 10 are coaxially arranged and housed. The case 1 is held so as to be swingable with respect to the vehicle body such as a side member via a suspension mechanism (not shown).

  The electric motor 10 includes an annular stator 11 and a rotor 12 disposed concentrically within the stator 11 and located inside the motor-side case portion 2.

  The stator 11 is provided by winding a coil 11a, and is fixed by press-fitting an outer peripheral surface to the inner periphery of the motor side case portion 2.

The rotor 12 includes a rotor rotating shaft 12a, a flange portion 12b, a laminated steel plate 12c, and a permanent magnet 12d.
The rotor rotating shaft 12a is rotatably supported by a first rotor bearing 13A fitted inside an opening 2a formed with one end penetrating the motor side case portion 2, and the other end of the reduction gear 20 will be described later. The second rotor bearing 13B fitted to the inner end of the carrier 24 is rotatably supported. And the laminated steel plate 12c is fixed to the outer periphery of the flange part 12b protruded from the rotor rotating shaft 12a in the radial direction, and the permanent magnet 12d is embedded in the outer periphery of the laminated steel plate 12c.
In this rotor 12, a permanent magnet 12d embedded in the outer periphery of the laminated steel plate 12c is disposed at an axial position facing the inner peripheral surface of the stator 11, and the rotor rotating shaft 12a is supported while maintaining this position.

  The speed reducer 20 is provided between the flange portion 12 b and the speed reducer side case portion 3. As shown in FIG. 2, the speed reducer 20 includes a sun gear 21 formed on the rotor rotating shaft 12 a, a ring gear 22 fixed in the speed reducer side case portion 3, a large-diameter pinion portion 23 a meshing with the sun gear 21, and a ring gear. A planetary gear set having three stepped pinions 23 (only one is shown here) that are integrally formed with a small-diameter pinion portion 23b that meshes with 22 and a carrier 24 that rotatably supports these stepped pinions 23. Consists of.

  The carrier 24 is an output member of the speed reducer 20, and is disposed between the rotor rotary shaft 12 a and the output shaft 25 at a position coaxial with both the shafts 12 a and 25. The carrier 24 supports three stepped pinions 23 arranged at equal intervals in the circumferential direction and rotatably supported, and includes carrier plates 24a and 24b facing each other. The carrier plates 24a and 24b are coupled to each other by a bolt 24d through a bridging portion 24c extending in the axial direction from one carrier plate 24a to the other carrier plate 24b. Then, three (only one is shown here) pinion shafts 24e are installed between the carrier plates 24a and 24b, and the stepped pinions 23 are rotatably supported by these pinion shafts 24e.

The output shaft 25 is an axle that rotates integrally with the wheel 30, one end is formed integrally with the carrier 24, and the other end penetrates the output shaft side case portion 4 and protrudes from the output shaft side case portion 4. A wheel hub (wheel side member) 26 is fitted. The output shaft 25 is rotatably supported with respect to the output shaft side case portion 4 by a hub bearing (wheel bearing) 40 disposed between the wheel hub 26 and the output shaft side case portion 4. Further, the brake drum 27 and the wheel 31 are overlapped on the wheel hub 26 and fixed with bolts, and the wheel hub 26 is prevented from coming off by a loading nut 28 screwed onto the tip of the output shaft 25.
In FIG. 1, reference numeral 29 denotes a back plate which is disposed so as to close the inner opening of the brake drum 27 and is attached to the output shaft side case portion 4, and a wheel cylinder (not shown) is attached to the back plate 29. The brake drum 27, that is, the wheel 30 is braked by the hydraulic operation of the wheel cylinder.

[Configuration of wheel bearing]
FIG. 3 is an enlarged view of part A in FIG. FIG. 4 is an enlarged view of a portion B in FIG. FIG. 5 is an enlarged view of a portion C in FIG.

  The hub bearing (wheel bearing) 40 is an output shaft side case of the case 1 which is a vehicle body side member provided so as to be swingable with respect to a vehicle body structure such as a side member (not shown) via a suspension mechanism (not shown). It is provided between the portion 4 and a wheel hub 26 which is a wheel side member provided so as to be integrally rotatable with the wheel 30, and the wheel hub 26 is rotatably supported with respect to the output shaft side case portion 4.

  As shown in FIG. 3, the hub bearing 40 includes an outer member 41, an inner member 42, a rolling element 43, and here two opposing surface portions 44 provided on both sides in the axial direction of the rolling element 43, 44.

  The outer member 41 is formed on the inner peripheral surface of a through-hole 4 a through which the output shaft 25 formed in the output shaft side case portion 4 passes, and here, is integrated with the output shaft side case portion 4. The outer surface 41 a facing the inner member 42 has outer rolling surfaces 41 b and 41 b that are in contact with the rolling elements 43 and 43. The outer rolling surface 41 b is a curved surface along the shape of the rolling element 43.

  The inner member 42 is formed by an outer peripheral surface of the wheel hub 26 and an inner member piece 42c fixed to the wheel hub 26. The outer side surface 42 a facing the outer member 41 has inner rolling surfaces 42 b and 42 b that are in contact with the rolling elements 43 and 43. The inner rolling surface 42 b is a curved surface along the shape of the rolling element 43.

  The rolling element 43 is a metal sphere that rotates between the outer member 41 and the inner member 42, and is rotatably held between the outer rolling surface 41b and the inner rolling surface 42b. Here, the rolling elements 43 are juxtaposed in the axial direction. Further, seal members 43a and 43a are provided on both axial sides of the rolling elements 43 and 43, respectively. The seal member 43a is a so-called grease seal.

  The facing surface portion 44 includes an outer facing surface portion 45 formed on the outer member 41 and an inner facing surface portion 46 formed on the inner member 42.

  The outer facing surface portion 45 has a first protrusion 45a provided between one seal member 43a and a rolling element 43 adjacent to the seal member 43a, and a tip position of a through hole 4a in contact with the other seal member 43a. 2nd protrusion 45b provided in the.

  As shown in FIG. 4, the first protrusion 45 a is a protrusion that protrudes from the outer surface 41 a of the outer member 41 toward the inner member 42, that is, along the axial direction of the wheel hub 26. It has a parallel surface 45a1 that faces the outer surface 42a of the side member 42 with a predetermined gap K, and a vertical surface 45a2 that wraps in the axial direction with a predetermined gap K from the inner facing surface portion 46. Here, the parallel surface 45a1 and the vertical surface 45a2 extend in directions orthogonal to each other. The “predetermined gap K” is a dimension that allows a relative positional shift between the outer member 41 and the inner member 42, and hereinafter the same dimension.

  As shown in FIG. 5, the second protrusion 45 b is a protrusion protruding along the axial direction of the wheel hub 26, and is a parallel surface 45 b 1 facing the outer surface 42 a of the inner member 42 with a predetermined gap K therebetween. And a vertical surface 45b2 that wraps in the axial direction with a predetermined gap K therebetween. Here, the parallel surface 45b1 and the vertical surface 45b2 extend in directions orthogonal to each other.

  The inner facing surface portion 46 is provided adjacent to the first protrusion 46a provided between one seal member 43a and the rolling element 43 adjacent to the seal member 43a, and the wheel 30 side of the other seal member 43a. Second protrusion 46b.

  As shown in FIG. 4, the first protrusion 46 a is a protrusion protruding from the outer surface 42 a of the inner member 42 toward the outer member 41, that is, along the axial direction of the wheel hub 26. It has a parallel surface 46a1 that faces the outer surface 41a of the side member 41 with a predetermined gap K, and a vertical surface 46a2 that wraps in the axial direction with a predetermined gap K between the outer facing surface portion 45. Here, the parallel surface 46a1 and the vertical surface 46a2 extend in directions orthogonal to each other. Further, the vertical surface 46 a 2 of the first protrusion 46 a of the inner facing surface portion 46 faces the vertical surface 45 a 2 of the first protrusion 45 a of the outer facing surface portion 45 in the axial direction.

  As shown in FIG. 5, the second protrusion 46 b is a wall surface extending in the axial direction from a part of the outer peripheral surface of the wheel hub 26 that is the inward member 42, and has a predetermined gap K from the outer facing surface portion 45. And a vertical surface 46b2 that wraps in the axial direction. The vertical surface 46b2 faces the vertical surface 45b2 of the second protrusion 45b of the outer facing surface portion 45 in the axial direction.

Next, the operation will be described.
First, “the wheel bearing of the comparative example and its problem” will be described, and the actions in the wheel bearing of the first embodiment will be described as “informing action at the time of axial displacement”, “informing action at the time of axial displacement”, “shaft The description will be divided into “informing action during tilt”.

[Comparative wheel bearings and problems]
Rolling bodies wear due to muddy water entering the vehicle bearings (hub bearings) when the vehicle travels on rough roads, or excessive load input to the vehicle bearings due to accidents. Thus, the relative positions of the outer member and the inner member of the vehicle bearing may be shifted. If this misalignment occurs, abnormal noise or vibration will occur with the rotation of the wheel, but this abnormal noise is caused by the misalignment and is very small. Continue running without noticing. As a result, the rolling element sandwiched between the outer member and the inner member is further reduced in diameter. As a result, the relative positional deviation between the outer member and the inner member is deteriorated, and the shaft shake of the axle supported by the vehicle bearing is generated.

  In particular, in the in-wheel motor shown in the first embodiment, since the axle is supported only by the vehicle bearing, the meshing of the planetary gear constituting the speed reducer is deteriorated by the inclination of the axle due to the shaft shake, and the wheel lock There is a risk of such abnormalities.

Further, in order not to transmit the shaft blur due to the abnormality of the vehicle bearing to the planetary gear of the reduction gear, the planetary gear output member (carrier 24 in the first embodiment) and the wheel bearing (hub bearing in the first embodiment). 40), it is conceivable to interpose a structure that absorbs axial blurring. Here, the “structure that absorbs axial blur” is a coupling structure, a joint structure, or the like that can absorb a shift.
However, in the case of interposing a structure that absorbs such shaft shake, the larger the assumed shaft shake, the greater the axial distance between the speed reducer and the wheel, resulting in an increase in the size of the entire unit. .

  Therefore, it is necessary to reduce the size of the shaft shake absorption structure by reducing the amount of shaft shake, and to suppress the increase in size of the unit. However, for example, in the case of detecting the occurrence of shaft shake using a high-precision sensor that detects the distance between the outer member and the inner member, not only the detection accuracy of the sensor itself but also high accuracy in mounting is provided. Required. For this reason, the manufacturing cost rises and the cost must be increased. In addition, the provision of the sensor increases the number of parts and increases the weight.

[Notification action at the time of axial displacement]
FIG. 6 is an enlarged view of a main part of the wheel bearing according to the first embodiment when a positional deviation occurs along the axial direction.

  In the in-wheel motor unit MU of the first embodiment, muddy water enters the hub bearing 40, excessive load input or the like occurs, and the rolling element 43 wears, so that the relative positions of the outer member 41 and the inner member 42 are changed. Consider the case where the output shaft 25 is displaced along the axial direction.

  Here, the hub bearing 40 is provided on the outer member 41 and the inner member 42, and has a facing surface portion 44 that faces with a predetermined gap K and wraps in the axial direction. That is, the vertical surface 45a2 of the first protrusion 45a of the outer facing surface portion 45 and the vertical surface 46a2 of the first protrusion 46a of the inner facing surface portion 46 are overlapped in the axial direction with a predetermined gap K therebetween. Further, the vertical surface 45b2 of the second protrusion 45b of the outer facing surface portion 45 and the vertical surface 46b2 of the second protrusion 46b of the inner facing surface portion 46 are overlapped in the axial direction with a predetermined gap K therebetween.

  Therefore, the relative positions of the outer member 41 along the axial direction of the output shaft 25 are predetermined so that the outer member 41 moves leftward in FIG. 6 and the inner member 42 moves rightward in FIG. If the gap K is shifted by the same dimension, the vertical surface 45a2 of the first protrusion 45a and the vertical surface 46a2 of the first protrusion 46a interfere with each other.

  Then, abnormal noise is generated due to interference between the vertical surfaces 45a2 and 46a2, and the driver is informed of the occurrence of an abnormality in the hub bearing 40, that is, the occurrence of relative displacement between the outer member 41 and the inner member 42. Is done.

  Thus, in the hub bearing 40 of the first embodiment, the relative position between the outer member 41 and the inner member 42 is a predetermined gap between the vertical surfaces 45a2 and 46a2 along the axial direction of the output shaft 25. At the stage where the same dimension as K is shifted, the opposing surface portion 44 can be caused to interfere to generate abnormal noise. For this reason, it is possible to detect an abnormality before deterioration of positional deviation with an inexpensive structure that does not use a sensor or the like. In other words, the relative axial displacement between the outer member 41 and the inner member 42 is suppressed by the “predetermined gap K”, and the axial blur amount can be reduced. As a result, it is possible to reduce the size of the shaft vibration absorbing structure and to suppress the increase in size of the unit.

  Further, the opposing surface portion 44 is opposed with a predetermined gap K and is wrapped in the axial direction, so that a labyrinth structure is provided between the outer member 41 and the inner member 42. For this reason, the opposing surface portion 44 can also have an effect of preventing entry of foreign matter such as muddy water and sand between the outer member 41 and the inner member 42.

[Notification action when the axis is displaced in the vertical direction]
FIG. 7 is an enlarged view of a main part of the wheel bearing according to the first embodiment when a positional deviation occurs along the axial direction.

  In the in-wheel motor unit MU of the first embodiment, muddy water enters the hub bearing 40, excessive load input or the like occurs, and the rolling element 43 wears, so that the relative positions of the outer member 41 and the inner member 42 are changed. Consider a case where the output shaft 25 is displaced along the axial direction (radial direction).

  Here, the hub bearing 40 is provided on the outer member 41 and the inner member 42, and has a facing surface portion 44 that faces with a predetermined gap K and wraps in the axial direction. That is, the parallel surface 45a1 of the first protrusion 45a of the outer facing surface portion 45 and the outer surface 42a of the inner member 42 face each other with a predetermined gap K therebetween. Further, the parallel surface 46a1 of the first protrusion 46a of the inner facing surface portion 46 and the outer surface 41a of the outer member 41 are opposed to each other with a predetermined gap K therebetween. Further, the parallel surface 45b1 of the second protrusion 45b of the outer facing surface portion 45 and the outer surface 42a of the inner member 42 face each other with a predetermined gap K therebetween.

  Therefore, as shown in FIG. 7, when the relative positions of the outer member 41 and the inner member 42 are shifted by the same dimension as the predetermined gap K along the axial direction of the output shaft 25, the parallel surface 45a1. And the outer surface 42a interfere, the parallel surface 46a1 and the outer surface 41a interfere, and the parallel surface 45b1 and the outer surface 42a interfere.

  Then, abnormal noise is generated due to interference between the parallel surfaces 45a1, 46a1, 45b1 and the outer surfaces 41a, 42a, and an abnormality of the hub bearing 40 occurs to the driver, that is, relative to the outer member 41 and the inner member 42. The occurrence of a misalignment is notified.

  As described above, in the hub bearing 40 of the first embodiment, the relative positions of the outer member 41 and the inner member 42 are the parallel surface 45a1 and the outer surface 42a that face each other along the direction perpendicular to the output shaft 25. At the stage where the same dimension as the predetermined gap K between the parallel surface 46a1 and the outer surface 41a and the predetermined gap K between the parallel surface 45b1 and the outer surface 42a are displaced by the same dimension. 44 can be made to interfere, and an abnormal noise can be actively generated. For this reason, it is possible to detect an abnormality before deterioration of positional deviation with an inexpensive structure that does not use a sensor or the like. That is, the relative axial displacement between the outer member 41 and the inner member 42 is suppressed to the “predetermined gap K”, and the amount of axial blur can be reduced. As a result, it is possible to reduce the size of the shaft vibration absorbing structure and to suppress the increase in size of the unit.

[Notification action when the axis is tilted]
FIG. 8 is an enlarged view of a main part of the wheel bearing according to the first embodiment when a positional deviation occurs in the inclination direction with respect to the axial direction.

  In the in-wheel motor unit MU according to the first embodiment, the rolling element 43 is worn due to intrusion of muddy water, excessive load input, or the like in the hub bearing 40, and the outer member 41 and the inner member in a direction inclined with respect to the output shaft 25. Consider a case where the relative position with respect to the member 42 is shifted. In FIG. 8, for example, a case is considered where the wheels 30 are tilted so as to rise upward.

  Here, the hub bearing 40 is provided on the outer member 41 and the inner member 42, and has a facing surface portion 44 that faces with a predetermined gap K and wraps in the axial direction.

  Therefore, as shown in FIG. 8, when the relative positions of the outer member 41 and the inner member 42 are shifted in the direction inclined with respect to the output shaft 25, the parallel surface 45 a 1 and the outer surface 42 a interfere with each other and become parallel. The surface 46a1 and the outer surface 41a interfere with each other.

  An abnormal noise is generated due to the interference between the parallel surfaces 45a1 and 46a1 and the outer surfaces 41a and 42a, and an abnormality of the hub bearing 40 occurs to the driver, that is, the relative positions of the outer member 41 and the inner member 42. The occurrence of the deviation is notified.

  As described above, in the hub bearing 40 according to the first embodiment, even when the relative position between the outer member 41 and the inner member 42 is shifted in the direction inclined with respect to the output shaft 25, the predetermined gap is set. At the stage where the dimension is shifted by the same dimension as or smaller than K, the opposing surface portion 44 can be made to interfere and positive noise can be generated. For this reason, it is possible to detect an abnormality before deterioration of positional deviation with an inexpensive structure that does not use a sensor or the like. The relative positional deviation between the outer member 41 and the inner member 42 can be suppressed to the “predetermined gap K” or less even when the outer member 41 and the inner member 42 are displaced in the tilting direction, and the amount of axial blur can be reduced. As a result, it is possible to reduce the size of the shaft vibration absorbing structure and to suppress the increase in size of the unit.

  In particular, in the hub bearing 40 of the first embodiment, as shown in FIG. 3, the opposed surface portions 44 are provided at both side positions in the axial direction of the rolling elements 43, 43.

  Therefore, for example, when the wheel 30 is tilted so as to be lowered toward the vehicle lower side, the parallel surface 45b1 and the outer surface 42a interfere with each other. Further, when the relative positions of the outer member shift along the axial direction of the output shaft 25 so that the outer member moves to the right in FIG. 6 and the inner member moves to the left in FIG. The vertical surface 45b2 of the second protrusion 45b interferes with the vertical surface 46b2 of the second protrusion 46b.

  Thus, by providing the opposing surface portion 44 at both axial positions of the rolling elements 43, 43, the opposing surface portion regardless of how the relative positions of the outer member 41 and the inner member 42 change. In 44, positive interference is generated, and abnormal noise can be generated positively and intentionally, and the scene of abnormality detection can be expanded.

Next, the effect will be described.
In the hub bearing (wheel bearing) of the first embodiment, the following effects can be obtained.

(1) Provided between a vehicle body side member (output shaft side case portion) 4 provided so as to be swingable with respect to the vehicle body, and a wheel side member (wheel hub) 26 provided so as to be rotatable integrally with the wheel 30; In a wheel bearing (hub bearing) 40 that rotatably supports the wheel side member 26 with respect to the vehicle body side member 4,
An outer member 41 having an outer rolling surface 41b fixed to the vehicle body side member 4 and in contact with the rolling elements 43 on the outer surface 41a;
An inner member 42 having an inner rolling surface 42b fixed to the wheel side member 26 and in contact with the rolling element 43 on an outer surface 42a facing the outer member 41;
An opposing surface portion 44 provided on the outer member 41 and the inner member 42, facing each other with a predetermined gap K and wrapping in the axial direction;
It was set as the structure provided with.
For this reason, it is possible to detect a relative positional shift between the outer member and the inner member with an inexpensive structure.

(2) The facing surface portions 44 are provided at both axial positions of the rolling element 43, respectively.
For this reason, regardless of the positional deviation direction between the outer member 41 and the inner member 42, it is possible to cause positive interference of the facing surface portion 44 and to enlarge the scene of abnormality detection.

(3) The rotating shaft (rotor rotating shaft) 12a of the electric motor 10 disposed in the wheel 31 of the wheel 30 and the axle (output shaft) 25 provided in the center of the wheel 30 are coaxially attached to face each other. Place and
The vehicle body side member is a motor case (case) 1 in which the electric motor 10 is housed.
The wheel side member is a wheel hub 26 fitted to the axle 25.
For this reason, when the axle shaft (output shaft) 25 supported only by the wheel bearing (hub bearing) 40 is slightly tilted, this tilt can be detected and the occurrence of an abnormality such as a wheel lock is prevented. be able to.

  As mentioned above, although the wheel bearing of this invention has been demonstrated based on Example 1, about a concrete structure, it is not restricted to these Examples, The summary of the invention which concerns on each claim of a claim As long as they do not deviate, design changes and additions are permitted.

  In the first embodiment, the opposing surface portions 44 provided on the outer member 41 and the inner member 42 have parallel surfaces 45a1 and 46a1 and vertical surfaces 45a2 and 46a2 that extend in directions orthogonal to each other. Absent. As shown in FIG. 9, the distal end surface 47 of the outer facing surface portion 45 formed on the outer member 41, that is, the surface facing the inner facing surface portion 46 with a predetermined gap K is provided along the axial direction along the inner member. It is inclined so as to gradually move away from the outer surface 42a of 42. On the other hand, the front end surface 48 of the inner facing surface portion 46 formed on the inner member 42, that is, the surface facing the front end surface 47 of the outer facing surface portion 45, is maintained along the axial direction while maintaining a predetermined gap K. The direction member 41 is inclined so as to gradually move away from the outer surface 41a.

  Thereby, the inclined front end surface 47 of the outer facing surface portion 45 and the inclined front end surface 48 of the inner facing surface portion 46 face each other with a predetermined gap K and wrap in the axial direction. As a result, even if the relative positions of the outer member 41 and the inner member 42 are shifted in either the axial direction or the axial direction, the front end surfaces 47 and 48 interfere with each other, so that abnormal noise is generated. Abnormality can be reported by generating it positively or intentionally.

  In the first embodiment, the opposing surface portion 44 is integrally formed on each of the outer surface 41a of the outer member 41 and the outer surface 42a of the inner member 42. However, the present invention is not limited to this. As shown in FIG. 10, the facing surface portion 44 may be formed as a member different from the outer member 41 and the inner member 42 and press-fitted into the outer member 41 and the inner member 42. Even in this case, the opposing surface portion 44 is opposed with a predetermined gap and is also wrapped in the axial direction, so that when the displacement occurs, the opposing surface portion 44 is caused to interfere and an abnormal noise is actively generated. Notification can be performed.

  Furthermore, the hub bearing 40 that is the wheel bearing of the first embodiment is applied to the in-wheel motor unit MU, but is not limited thereto. It can also be applied as a bearing for supporting a wheel in a general engine vehicle or hybrid automatic.

  In the hub bearing 40 that is the wheel bearing of the first embodiment, a part of the output shaft side case portion 4 that is the vehicle body side member is the outer member 41 and a part of the wheel hub 26 that is the wheel side member. And the inner member 42 was comprised by the inner member piece 42c. However, the present invention is not limited thereto, and the outer member 41 may be configured as a separate member with respect to the vehicle body side member, or the inner member 42 may be configured as a separate member with respect to the wheel side member.

  Further, the vehicle body side member is not limited to the output side case portion 4 but may be a trailing arm or the like extending so as to be able to swing from the vehicle body. Further, the wheel-side member is not limited to the wheel hub 26 but may be an axle connected to the wheel.

1 Case 4 Output shaft side case part (vehicle body side member)
10 Electric motor (drive source)
11 Stator 12 Rotor 12a Rotor Rotating Shaft 20 Reducer 25 Output Shaft 26 Wheel Hub (Wheel Side Member)
40 Hub bearing 41 Outer member 41a Outer side surface 41b Outer rolling surface 42 Inner member 42a Outer side surface 42b Inner transfer surface 43 Rolling body 44 Opposing surface portion 45 Outer facing surface portion 45a First projection 45a1 Parallel surface 45a2 Vertical surface 45b Second projection 45b1 Parallel surface 45b2 Vertical surface 46 Inner facing surface portion 46a First protrusion 46a1 Parallel surface 46a2 Vertical surface 46b Second protrusion 46b2 Vertical surface

Claims (2)

A wheel provided between a vehicle body side member provided so as to be swingable with respect to the vehicle body and a wheel side member provided so as to be capable of rotating integrally with the wheel, and rotatably supporting the wheel side member with respect to the vehicle body side member. For bearings,
An outer member fixed to the vehicle body side member and having an outer rolling surface in contact with a rolling element on the outer surface;
An inner member fixed to the wheel side member and having an inner rolling surface in contact with the rolling element on an outer surface facing the outer member;
A projection formed integrally with the outer member from the outer surface of the outer member; and a projection formed integrally with the outer member; and projecting from the outer surface of the inner member toward the outer member. A projecting surface formed integrally with the member, and a facing surface portion that faces with a predetermined gap and wraps in the axial direction;
With
The wheel bearing according to claim 1, wherein the facing surface portion is disposed between a sealing member provided between the outer member and the inner member and the rolling element. The wheel bearing according to claim 1,
The rotating shaft of the electric motor arranged in the wheel of the wheel and the axle provided in the center of the wheel are coaxially attached to face each other,
The vehicle body side member is a motor case that houses the electric motor,
The wheel bearing, wherein the wheel side member is a wheel hub fitted to the axle.