JP2019018839A - Power device for vehicle and wheel bearing device with generator - Google Patents

Abstract

To provide a power device for a vehicle which can prevent an abnormality or the like of an electric motor or a generator by efficiently discharging the heat of the electric motor or the generator which is constituted in a brake rotor, and can prevent the lowering of brake performance, the deterioration of a lubricant in a bearing, and the lowering of the rigidity of a bearing material, and a wheel bearing device with the generator.SOLUTION: A power device 1 for a vehicle comprises a wheel bearing 2 and an electric motor 3 having a stator attached to an outer ring 4, and a motor rotor 19 attached to an inner ring 5. The electric motor 3 is smaller in a diameter as a whole than an external peripheral face being a portion to which a brake caliper in a brake rotor 12 is pressed, and an entire part except for an attachment part of the electric motor 3 to a hub flange 7 is located within a range in an axial direction between a vehicle body attachment face 4a of the wheel bearing 2 at an in-board side and the hub flange 7. An irregular part 22 for cooling the electric motor 3 is arranged at the external peripheral face of the electric motor 3.SELECTED DRAWING: Figure 1

Description

  The present invention provides a vehicle power device and a generator that are provided separately from a motor, an internal combustion engine, or a hybrid type main drive source that combines these in a vehicle such as front wheel drive or rear wheel drive to improve vehicle performance. The present invention relates to a bearing device for an attached wheel.

A mounting structure for a wheel rotating motor has been proposed (for example, Patent Document 1).
In this mounting structure, a wheel hub that rotates integrally with the wheel, a bearing that rotatably supports the wheel hub, a bearing support member that supports the flange portion of the bearing in contact with the wheel side portion, and A suspension device attached between the vehicle body and the wheel and supporting the bearing support member. The rotary motor includes a flange portion, and the bearing and the rotary motor are integrally formed to share the flange portion of the wheel rotary motor, so that the rotary motor can be attached to the vehicle body without greatly modifying the suspension portion.

Japanese Patent No. 4348941

  In the configuration described in Patent Document 1, the motor projects in the axial direction of the axle, and it is necessary to change the structure of the vehicle body mounting portion (knuckle portion). In order to improve the motor torque, if the size of the motor housing in the radial direction is increased, the motor housing interferes with surrounding suspension devices, so that a reduction gear is generally incorporated.

  Therefore, the present applicant has proposed a direct drive system in which the motor is incorporated in the brake rotor, the radial dimension of the motor is ensured, the mounting portion is not greatly modified, and a speed reducer is not used. Application 2006-184295).

  However, when the motor is operated, the motor generates heat due to iron loss and copper loss, and when the vehicle is braked, there is a heat source around the motor due to frictional heat between the brake rotor and the brake pad. In the configuration in which the motor is incorporated in the brake rotor, there is no means for dissipating heat, and the deterioration of the insulation performance of the coil and the like is accelerated due to the temperature rise of the motor, which causes the motor to malfunction. In order to prevent the motor performance from being deteriorated due to the thermal demagnetization of the magnet, the demagnetization of the coil, etc., it is necessary to limit the amount of drive current, etc., so that the motor performance cannot be fully exhibited. Further, the axle bearing is also exposed to a high temperature for a long time, thereby causing deterioration of the lubricant and reduction of the strength of the metal material.

  An object of the present invention is to efficiently release the heat of an electric motor or a generator configured in a brake rotor, thereby preventing an abnormality of the electric motor or the generator, reducing brake performance, and reducing the lubricant in the bearing. It is an object of the present invention to provide a vehicular power unit and a generator-equipped wheel bearing device that can prevent deterioration and a decrease in strength of a bearing material, respectively.

The wheel bearing device with a generator according to the present invention has a fixed wheel and a hub flange, and is rotatably supported by the fixed wheel via a rolling element so that a wheel and a brake rotor of a vehicle are attached to the hub flange. In a wheel bearing device with a generator, comprising: a wheel bearing having a wheel; a generator attached to a stator attached to the fixed wheel; and a rotor attached to the rotating wheel;
A portion of the brake rotor is located radially outward of the generator;
A plurality of uneven portions are provided on one or both of the inner peripheral surface of the brake rotor and the outer peripheral surface of the generator.

  According to this configuration, since the rotor of the generator is a direct drive type attached to the rotating wheel of the wheel bearing, the configuration of the generator is simple and space-saving, and an increase in vehicle weight is also suppressed. In particular, the generator as a whole is smaller in diameter than the outer peripheral portion of the brake rotor, and the entire generator except for the attachment portion to the hub flange in the generator is composed of a vehicle body mounting surface on the inboard side of the wheel bearing and the hub flange. Located in the axial range between. For this reason, the brake caliper that presses the friction pad against the brake rotor does not interfere with the generator, and the installation of the brake is not hindered by the installation of the generator.

  Moreover, the uneven | corrugated | grooved part which cools a generator is provided in any one or both of the internal peripheral surface of a brake rotor, and the outer peripheral surface of a generator. This uneven portion increases the surface area of the brake rotor or generator, which is a heat source, and generates an air flow by the rotation of the rotating wheel, facilitating heat exchange on the surface of the brake rotor or generator. Therefore, it is possible to prevent an abnormality caused by the temperature rise of the generator. Further, heat generated in the brake rotor is released to the outside of the brake rotor by the air flow. Brake performance can be maintained by lowering the operating temperature of the brake. In addition, since the wheel bearing can be prevented from being exposed to a high temperature for a long time, the deterioration of the lubricant in the bearing and the decrease in the strength of the bearing material can be prevented.

  The generator is an outer rotor motor in which the stator is positioned on the outer periphery of the wheel bearing, and the rotor is positioned radially outward of the stator. Compared with power generation efficiency. The uneven portion may be provided on one or both of the inner peripheral surface of the brake rotor and the outer peripheral surface of the rotor. In particular, when an uneven portion is provided on the outer peripheral surface of the rotor, the outer rotor type has a structure in which air circulation is easier than the inner rotor type.

  A vent hole may be provided in the brake rotor. In this case, the air in the brake rotor is easily circulated. That is, the heat generated in the brake rotor is released to the outside of the brake rotor through the vents due to the air flow caused by the uneven portions.

  The uneven portion may have a fin shape. In this case, since air can be stirred and the flow of air can be generated strongly, the cooling effect can be enhanced. In the case where the concavo-convex portion has an axial flow fin shape, the cooling effect can be further enhanced by continuously compressing air.

  The wheel bearing may be a bearing that supports a driven wheel that is mechanically disconnected from the main drive source of the vehicle. In this case, since the generator has a simple and space-saving configuration, the generator can be easily installed on the driven wheel without greatly changing the configuration of a general wheel bearing and brake.

  The generator may be a travel assist motor generator capable of rotationally driving the driven wheel by being supplied with power. In this case, by driving the motor generator in accordance with the running state of the vehicle, etc., the main drive source can be driven so as to have a rotational speed and torque with improved efficiency, and the running performance of the vehicle can be improved.

  The generator may be a motor generator capable of rotationally driving the wheel by being supplied with power. In this case, the driving performance of the vehicle can be improved by driving the motor generator in accordance with the driving state of the vehicle. For example, the driving performance of the vehicle can be further improved by driving the driven wheel and the driving wheel with a motor generator, respectively.

The vehicle power device of the present invention has a fixed wheel and a hub wheel, and a rotating wheel that is rotatably supported by the fixed wheel via a rolling element, and on which the vehicle wheel and a brake rotor are attached. Wheel bearings;
In a vehicle power device comprising: a stator attached to the fixed wheel; and an electric motor having a motor rotor attached to the rotating wheel.
A portion of the brake rotor is located radially outward of the electric motor;
A plurality of uneven portions are provided on one or both of the inner peripheral surface of the brake rotor and the outer peripheral surface of the electric motor.

According to this configuration, by driving the electric motor in accordance with the traveling state of the vehicle and the like, the main drive source can be driven at the rotation speed and torque that improve the efficiency, and the traveling performance of the vehicle can be improved. Further, since the motor rotor is a direct drive type attached to the rotating wheel of the wheel bearing, the configuration of the electric motor is simple and space-saving, and an increase in vehicle weight can be suppressed. In particular, the entire motor has a smaller diameter than the outer peripheral portion of the brake rotor, and the entire motor except for the mounting portion to the hub flange in the motor is a vehicle body mounting surface on the inboard side of the wheel bearing, and the hub flange. Located in the axial range between. For this reason, the brake caliper that presses the friction pad against the brake rotor does not interfere with the electric motor, and the installation of the brake is not hindered by the installation of the electric motor.
Moreover, the uneven | corrugated | grooved part which cools an electric motor is provided in any one or both of the internal peripheral surface of a brake rotor, and the outer peripheral surface of an electric motor. The uneven portion increases the surface area of the brake rotor or electric motor, which is a heat generation source, and generates an air flow by the rotation of the rotating wheel, thereby facilitating heat exchange on the surface of the brake rotor or electric motor. Therefore, it is possible to prevent an abnormality caused by the temperature rise of the electric motor. Further, heat generated in the brake rotor is released to the outside of the brake rotor by the air flow. Brake performance can be maintained by lowering the operating temperature of the brake. In addition, since the wheel bearing can be prevented from being exposed to a high temperature for a long time, the deterioration of the lubricant in the bearing and the decrease in the strength of the bearing material can be prevented.

  The wheel bearing device with a generator according to the present invention has a fixed wheel and a hub flange, and is rotatably supported by the fixed wheel via a rolling element so that a wheel and a brake rotor of a vehicle are attached to the hub flange. A wheel bearing device with a generator, comprising: a wheel bearing having a wheel; a stator attached to the fixed wheel; and a generator having a rotor attached to the rotating wheel; part of the brake rotor However, it is located radially outward of the generator, and includes an uneven portion for cooling the generator on one or both of the inner peripheral surface of the brake rotor and the outer peripheral surface of the generator. For this reason, by efficiently releasing the heat of the generator configured in the brake rotor, the abnormality of the generator is prevented, the brake performance is deteriorated, the lubricant in the bearing is deteriorated, and the strength of the bearing material Each drop can be prevented.

  The vehicle power device of the present invention has a fixed wheel and a hub wheel, and a rotating wheel that is rotatably supported by the fixed wheel via a rolling element, and on which the vehicle wheel and a brake rotor are attached. A vehicle power unit comprising a wheel bearing, a stator attached to the fixed wheel, and a motor having a motor rotor attached to the rotating wheel, wherein a part of the brake rotor is a radial direction of the motor A plurality of uneven portions are provided on either or both of the inner peripheral surface of the brake rotor and the outer peripheral surface of the electric motor. For this reason, by efficiently releasing the heat of the electric motor configured in the brake rotor, the abnormality of the electric motor is prevented, the brake performance is deteriorated, the lubricant in the bearing is deteriorated, and the strength of the bearing material is reduced. Each can be prevented.

1 is a cross-sectional view of a generator-equipped wheel bearing device (vehicle power device) according to an embodiment of the present invention. It is the fracture | rupture perspective view which looked at the vehicle power device from the vehicle body side. It is a perspective view of the principal part of the power device for vehicles. It is sectional drawing of the vehicle power unit which concerns on other embodiment of this invention. It is a fractured perspective view of the vehicle power unit. It is a fractured perspective view of the important section of the vehicle power unit. It is a perspective view of the principal part of the power device for vehicles. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a perspective view of the vehicle power unit which concerns on other embodiment of this invention. It is a figure which shows the flow of the air of the vehicle power unit which concerns on further another embodiment of this invention. It is a block diagram which shows the conceptual structure of the system for vehicles using one of the vehicle power devices. It is a power supply system figure which becomes an example of the vehicle carrying the system for vehicles. It is explanatory drawing of the concept of the other system for vehicles using the power unit for vehicles.

A wheel bearing device with a generator (vehicle power device) according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the generator wheel bearing device 1 includes a wheel bearing 2 and a generator 3. As will be described later, when the generator 3 is a motor generator (motor) for driving assistance capable of rotating the wheels 10, this wheel bearing device with a generator is synonymous with “vehicle power device”. is there.

<About wheel bearing 2>
The wheel bearing 2 includes an outer ring 4 that is a fixed ring, a double row rolling element 6, and an inner ring 5 that is a rotating wheel. An inner ring 5 is rotatably supported on the outer ring 4 via double row rolling elements 6. The inner ring 5 has a hub flange 7 at a location protruding from the outer ring 4 toward the outboard side in the axial direction. The outer ring 4 is attached to the underbody frame part 8 such as a knuckle with a bolt (not shown) on the vehicle body attachment surface 4a that is the end (inboard side) opposite to the hub flange 7, and supports the weight of the vehicle body. . In this specification, the side closer to the outside in the vehicle width direction of the vehicle when the vehicle power unit 1 is mounted on the vehicle is referred to as the outboard side, and the side closer to the center in the vehicle width direction of the vehicle is referred to as the inboard side. Called the board side.

  The rim 11 of the wheel 10 and the brake rotor 12 are attached to the side surface on the outboard side of the hub flange 7 with a hub bolt 13 in a state where they overlap each other in the axial direction. A tire 14 is attached to the outer periphery of the rim 11.

<About brake 17>
The brake 17 is a friction brake including a disc-type brake rotor 12 and a brake caliper (not shown). The brake rotor 12 has a flat plate-like portion 12a and an outer peripheral portion 12b. The flat plate-like portion 12 a is an annular and flat plate-like member that overlaps the hub flange 7. The outer peripheral portion 12 b extends from the flat plate-like portion 12 a to the outer peripheral side of the outer ring 4. The outer peripheral portion 12b includes a cylindrical portion 12ba extending in a cylindrical shape from the outer peripheral edge portion of the flat plate portion 12a toward the inboard side, and a flat plate portion 12bb extending in a flat plate shape from the inboard side end of the cylindrical portion 12ba toward the outer diameter side. And have.

  The brake caliper has a friction pad (not shown) that sandwiches the flat plate portion 12bb of the brake rotor 12. The brake caliper is attached to the underbody frame part 8. The brake caliper may be either a hydraulic type or a mechanical type, and may be an electric motor type.

<About generator 3>
The generator 3 in this example is a travel assisting motor generator (electric motor) capable of rotating the wheel 10 by generating electric power by rotating the wheel 10 and supplying power. Hereinafter, the generator 3 may be referred to as the electric motor 3. The electric motor 3 includes a stator 18 attached to the outer peripheral surface of the outer ring 4 and a motor rotor (rotor) 19 attached to the hub flange 7 of the inner ring 5. The electric motor 3 in the illustrated example is an outer rotor type IPM (Interior Permanent Magnet Motor) synchronous motor, but may be an outer rotor type SPM (Surface Permanent Magnet Motor) synchronous motor.

  In addition, the electric motor 3 can employ various types such as a switched reluctance motor (abbreviation: SR motor), an induction motor (abbreviation: IM), and the like. In the synchronous motor, a distributed winding type and a concentrated winding type can be adopted as the winding type of the stator 18.

  The stator 18 includes a core 18a and a coil (not shown) wound around each tooth of the core 18a. The motor rotor 19 includes a rotating case 19a serving as a motor case, a magnetic body 19b provided on the inner periphery of the rotating case 19a, and a permanent magnet (not shown) built in the magnetic body 19b. The rotating case 19a is a hub. Attached to the flange 7. The inner peripheral surface on the outboard side of the rotating case 19a is fixed to the outer peripheral surface of the hub flange 7 by, for example, fitting, welding, or adhesion. A motor shield 21 is attached to one end on the inboard side of the rotating case 19a. The motor shield 21 closes one end of the rotating case 19a on the inboard side, and prevents foreign matter from entering the electric motor 3 from the suspension frame component 8 side.

  The entire electric motor 3 has a smaller diameter than the outer peripheral portion 12 b of the brake rotor 12. Further, the whole of the electric motor 3 excluding the attachment portion to the hub flange 7 is located in the axial range L <b> 1 between the vehicle body attachment surface 4 a on the inboard side of the wheel bearing 2 and the hub flange 7. That is, the electric motor 3 is accommodated in a radial range between the outer peripheral portion 12b of the brake rotor 12 and the outer periphery of the outer ring 4, and the electric motor 3 is connected to the cylindrical portion 12ba in the outer peripheral portion 12b of the brake rotor 12 for the axial range L1. Part of 3 (outboard side half) is included.

<About cooling structure>
In the cooling structure of this embodiment, the uneven portion 22 is provided on the outer peripheral surface of the electric motor 3, and air is circulated by the rotation of the wheel bearing 2 to release heat.
FIG. 3 is a perspective view of the vehicle power unit 1. In FIG. 3, the brake rotor and the like are omitted from FIG. As shown in FIG. 3, the uneven | corrugated | grooved part 22 which cools this electric motor 3 (FIG. 2) is provided in the outer peripheral surface of the rotation case 19a. The uneven portion 22 increases the surface area of the electric motor 3 (FIG. 2) that is a heat generation source, and generates an air flow by the rotation of the inner ring 5 to facilitate heat exchange. The plurality of uneven portions 22 in this example includes a plurality of concave portions 22a and a plurality of convex portions 22b. Each recess 22a has a dimple shape that is recessed more concavely than the outer peripheral surface of the rotating case 19a. Each protrusion 22b protrudes in a hemispherical shape from the outer peripheral surface of the rotating case 19a.

  The uneven portion 22 may be formed on the outer peripheral surface of the rotating case 19a using, for example, a mold, or the uneven portion 22 may be processed by machining. In addition, only the concave portion 22a of the concavo-convex portion 22 may be formed by a mold or machining, and the convex portion 22b may be fixed to the outer peripheral surface of the rotating case 19a as a separate part by welding or the like. On the outer peripheral surface of the rotating case 19a, a plurality of concave portions 22a are arranged at regular intervals in the axial direction, and a plurality of convex portions 22b are arranged at regular intervals in the axial direction with a predetermined interval in the circumferential direction with respect to the concave portions 22a. Lined up. The row of recesses 22a arranged in the axial direction and the row of projections 22b arranged in the axial direction are provided on the outer peripheral surface of the rotating case 19a so as to appear alternately in the circumferential direction.

  As shown in FIG. 1, an annular gap δ is provided between the inner peripheral surface of the cylindrical portion 12ba of the brake rotor 12 and the outer peripheral surface of the rotary case 19a in order to improve heat dissipation. The annular gap δ is a gap that is arbitrarily determined by design, for example, and is determined by determining an appropriate gap by, for example, one or both of testing and simulation.

<Effects>
By the way, the above-mentioned friction brake is common as a braking device for a vehicle. When a friction brake is applied, it converts kinetic energy into thermal energy to produce a braking force. In a disc brake for an automobile, the temperature of the brake surface and the caliper may reach 600 ° C. to 1000 ° C. in some cases. An electric motor that is an electric motor generator is a device that converts electrical energy into rotational energy or rotational energy into electrical energy. The electric motor generator operates as a drive motor when the vehicle travels, and generates heat due to losses such as copper loss due to coil conductor resistance and iron loss due to eddy current. Further, when the vehicle is braked, it operates as a generator and generates a regenerative current, so that heat is generated mainly due to copper loss.

  In an automobile having a general structure, the entire electric motor 3 has a smaller diameter than the outer peripheral portion 12 b of the brake rotor 12. Further, the whole of the electric motor 3 excluding the attachment portion to the hub flange 7 is located in the axial range between the inboard side vehicle body attachment surface 4 a of the wheel bearing 2 and the hub flange 7. For this reason, the electric motor 3 can be incorporated without significantly remodeling the vehicle body, which contributes to a reduction in fuel consumption of the automobile and an improvement in vehicle power performance.

  However, in the case of the above-described configuration, the heat source concentrates in the brake rotor 12 due to the frictional heat generated by the rotation of the wheel bearing 2 in addition to the heat generated by the brake rotor 12 and the heat generated by the electric motor 3. Therefore, in the conventional configuration in which an electric motor is incorporated inside the brake rotor, the heat generated in the brake rotor has only a heat radiation path to the outside through only the heat radiation of the brake rotor itself and the heat conduction through the contact portion with the vehicle body. It becomes hot. When the brake becomes hot, heat is transmitted to the brake fluid, which may cause vapor lock in the brake fluid, fading phenomenon due to overheating of the brake pad, excessive wear of the brake pad, and the like. Further, when the electric motor having the power assist function becomes high temperature, an abnormality of the insulating coating of the motor coil, or in the case of a magnet type motor, thermal demagnetization of the magnet occurs, and the performance of the motor is remarkably deteriorated. In wheel bearings, thermal deterioration of the lubricant and reduction in strength of the metal material occur, reducing the bearing life.

  Therefore, in the present embodiment, the direct drive type electric motor 3 is configured, and a plurality of uneven portions 22 for cooling the electric motor 3 are provided on the outer peripheral surface of the rotary case 19a. The uneven portion 22 increases the surface area of the electric motor 3 that is a heat generation source, and also generates a flow of air by the rotation of the inner ring 5 to facilitate heat exchange. Further, since the surface area of the electric motor 3 is increased, heat exchange is performed even when the vehicle is stationary.

  Therefore, it is possible to prevent an abnormality caused by the temperature rise of the electric motor 3 in advance. Further, heat generated in the brake rotor 12 is released out of the brake rotor 12 through the annular gap δ by the air flow. Thereby, the brake performance can be maintained by lowering the operating temperature of the brake 17. Since the wheel bearing 2 can be prevented from being exposed to a high temperature for a long time, deterioration of the lubricant in the bearing and strength reduction of the bearing material can be prevented. Thereby, the bearing life can be extended.

<About other embodiments>
In the following description, the same reference numerals are given to portions corresponding to the matters described in advance in the respective embodiments, and overlapping descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in advance unless otherwise specified. The same effect is obtained from the same configuration. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

  As shown in FIGS. 4-7, the structure by which the several uneven | corrugated | grooved part 22 which consists of fin shape was provided in the outer peripheral surface of the rotation case 19a may be sufficient. The plurality of concavo-convex portions 22 of this example includes a convex portion 22b composed of a plurality of fins provided at predetermined intervals on the outer peripheral surface of the rotating case 19a, and a concave portion 22a between the fins. Each fin is a centrifugal type that inclines in one circumferential direction as it goes from the outboard side to the inboard side on the outer peripheral surface of the rotating case 19a. An annular gap δ is provided between the inner peripheral surface of the cylindrical portion 12ba of the brake rotor 12 and the outer peripheral surface of the rotating case 19a in order to improve heat dissipation.

  According to this configuration, the surface of the electric motor 3 can be increased by the plurality of concave and convex portions 22 each having a fin shape, and the air can be agitated by the rotation of the inner ring 5 to generate a strong air flow. The effect can be enhanced. Heat generated in the brake rotor 12 is forcibly released from the annular gap δ to the outside of the brake rotor 12 by the air flow. The fin is not limited to the centrifugal type. For example, when the concavo-convex portion 22 has an axial flow fin shape, the cooling effect can be further enhanced by continuously compressing air.

As shown in FIG. 8, the plurality of uneven portions 22 may have a configuration in which a plurality of grooves (concave portions) 25 extending in parallel with the rotation axis direction are provided on the outer peripheral surface (convex portion) of the rotating case 19a. The plurality of grooves 25 are provided at predetermined intervals in the circumferential direction. Each groove 25 extends a predetermined distance from the inboard side end on the outer peripheral surface of the rotating case 19a to the outboard side. The width of each groove 25 is set to the same width. The dimension in the axial direction, the width dimension, and the dent amount from the outer peripheral surface of each groove 25 are appropriately determined by a test or simulation. For example, the groove 25 may be formed on the outer peripheral surface of the rotating case 19a by a mold or the like, or the groove 25 may be processed by machining.
According to the configuration of FIG. 8, there is an effect of releasing the air that has become high temperature on the inner peripheral side of the brake rotor 12 (FIG. 2) along the plurality of grooves 25 to the outside. Moreover, since the surface area of the outer peripheral surface of the rotation case 19a increases, the heat radiation from the rotation case 19a is promoted.

As shown in FIG. 9, the plurality of concavo-convex portions 22 may have a configuration in which a plurality of grooves (concave portions) 26 extending in the rotation axis direction are provided on the outer peripheral surface (convex portion) of the rotating case 19a. The plurality of grooves 26 are provided at predetermined intervals in the circumferential direction, and each groove 26 extends from the inboard side end on the outer peripheral surface of the rotating case 19a to the outboard side by a predetermined distance. The width dimension 26H of each groove 26 is set so as to increase in width from the outboard side toward the inboard (suspension frame component 8) side.
According to the configuration of FIG. 9, since the surface area of the outer peripheral surface of the rotating case 19a is increased, heat dissipation from the rotating case 19a is promoted. Since the width dimension 26H of each groove 26 is set so as to increase toward the undercarriage frame component 8, the air that has become hot on the inner peripheral side of the brake rotor 12 (FIG. 2) is more efficiently released to the outside. be able to.

As shown in FIG. 10, the plurality of uneven portions 22 may have a structure in which a plurality of annular grooves 27 in the circumferential direction are provided on the outer peripheral surface (convex portion) of the rotating case 19a. The plurality of annular grooves 27 are provided at predetermined intervals in the axial direction. Although not shown, the annular groove 27 may be a spiral groove.
According to the configuration of FIG. 10, since the surface area of the outer peripheral surface of the rotating case 19a is increased, heat dissipation from the rotating case 19a is promoted.

As shown in FIG. 11, the plurality of uneven portions 22 may have a structure in which a plurality of annular grooves 28 in the circumferential direction are provided on the outer peripheral surface (convex portion) of the rotating case 19a. The plurality of annular grooves 28 are provided at predetermined intervals in the axial direction, and each annular groove 28 has a wave shape in the rotational axis direction.
According to the configuration of FIG. 11, since the surface area of the outer peripheral surface of the rotating case 19a is further increased, the heat dissipation effect from the rotating case 19a is great. Further, due to the wave shape of the annular groove 28, an air flow is generated during wheel rotation, and the rotating case 19a is cooled.

  As shown in FIG. 12, a plurality of vent holes 23 penetrating in the axial direction may be provided in the flat plate-like portion 12 a of the brake rotor 12. These vent holes 23 are provided at regular intervals in the circumferential direction at portions on the outer peripheral side of the flat plate-like portion 12a. According to this configuration, the air in the brake rotor 12 is easily circulated. That is, the heat generated in the brake rotor 12 is released to the outside of the brake rotor 12 through the vent hole 23 due to the air flow by the uneven portion 22 (FIG. 6). Further, the heat generated in the brake rotor 12 is also released to the outside of the brake rotor 12 from the annular gap δ (FIG. 5) by the air flow, as in the above-described embodiments.

  As shown in FIG. 13, a plurality of vent holes 24 penetrating in the radial direction may be provided in the cylindrical portion 12ba of the brake rotor 12 at regular intervals in the circumferential direction. Also in this case, the heat generated in the brake rotor 12 is released to the outside of the brake rotor 12 through the vent hole 24 due to the air flow by the uneven portion 22. Further, the heat generated in the brake rotor 12 is released to the outside of the brake rotor 12 from the annular gap δ (FIG. 5) by the air flow.

As shown in FIG. 14, the brake rotor 12 may be provided with a plurality of vent holes 23 penetrating in the axial direction (configuration of FIG. 12), and the brake rotor 12 may be provided with a plurality of vent holes 24 penetrating in the radial direction. (Configuration of FIG. 13). 14, the heat generated in the brake rotor 12 passes through the vent holes 23 and 24 penetrating in the axial direction and the radial direction to the outside of the brake rotor 12 as indicated by the thick arrows in FIG. It is released smoothly. Further, the heat generated in the brake rotor 12 is released to the outside of the brake rotor 12 from the annular gap δ by the air flow.
Although not shown, the brake rotor 12 may be a ventilated disk. In this case, the heat dissipation of the brake rotor 12 is improved.

  The electric motor 3 can also be an inner rotor type. However, when the concave and convex portion is provided on the outer peripheral surface of the inner rotor type electric motor, the surface area of the electric motor 3 is increased, so that an effect of heat exchange is exerted. However, the outer rotor type is more likely to exhibit the effect of the present invention. Easy air circulation. In order to generate a larger torque in a limited space, an outer rotor type in which the moment generation position is on the outer diameter side is desirable.

A plurality of convex portions 22b are provided at predetermined intervals on the outer peripheral surface of the rotating case 19a, and the concave and convex portions 22 include the convex portions 22b and a concave portion forming the outer peripheral surface of the rotating case 19a between adjacent convex portions. Also good.
A plurality of concave portions 22a are provided on the outer peripheral surface of the rotating case 19a at predetermined intervals, and the concave and convex portions 22 may include the concave portions 22a and convex portions forming the outer peripheral surface of the rotating case 19a between adjacent concave portions. .
The uneven portion 22 may be provided on one or both of the inner peripheral surface and the outer peripheral surface of the cylindrical portion 12ba of the brake rotor 22. Also in this case, the same effects as the configuration in which the uneven portion 22 is provided on the outer peripheral surface of the rotating case 19a are obtained. However, it is difficult to process the uneven portion 22 on the inner peripheral surface of the cylindrical portion 12ba, and when the uneven portion 22 is provided on the outer peripheral surface of the cylindrical portion 12ba, it is necessary to pay attention to interference with the brake caliper.

<Vehicle system>
FIG. 15 is a block diagram showing a conceptual configuration of a vehicle system using any one of the vehicle power devices 1.
In this vehicle system, the vehicle power unit 1 is mounted on the driven wheel 10 _B in the vehicle 2 having the driven wheel 10 _B that is mechanically disconnected from the main drive source. Wheel bearing 2 in the vehicle power unit 1 (FIG. 1) is a bearing supporting the driven wheel 10 _B.

The main drive source 35 is an internal combustion engine such as a gasoline engine or a diesel engine, a motor generator (electric motor), or a hybrid drive source that combines both. The “motor generator” is referred to as an electric motor capable of generating electricity by applying rotation. In the illustrated example, the vehicle 30 is a front wheel drive vehicle in which the front wheels are drive wheels 10 _A and the rear wheels are driven wheels 10 _B, and the main drive source 35 is an internal combustion engine 35 a and a motor generator 35 b on the drive wheels side. This is a hybrid vehicle (hereinafter sometimes referred to as “HEV”).

Specifically, it is a mild hybrid type in which the motor generator 35b on the drive wheel side is driven at a medium voltage such as 48V. Hybrids are broadly divided into strong hybrids and mild hybrids. Mild hybrids are the main drive source that is an internal combustion engine, and it is a type that mainly assists driving with a motor when starting or accelerating. The (electric vehicle) mode is distinguished from a strong hybrid by being able to perform normal driving for a while but not for a long time. Internal combustion engine 35a of the example of the figure, is connected to the drive shaft of the drive wheel 10 _A via the clutch 36 and speed reducer 37, the motor generator 35b of the driving wheel is connected to a reduction gear 37.

System for a vehicle includes an electric motor 3 is a motor generator for driving auxiliary for rotating driving of the driven wheels 10 _B, the individual control means 39 for controlling the electric motor 3, the individual control is provided in the upper ECU40 And an individual motor generator command means 45 for outputting a command for causing the means 39 to control driving and regeneration. The electric motor 3 is connected to power storage means. As this power storage means, a battery (storage battery), a capacitor, a capacitor, or the like can be used. The type and the mounting position on the vehicle 30 are not limited, but in this embodiment, the low voltage battery 50 mounted on the vehicle 30 and The medium voltage battery 49 is the medium voltage battery 49.

The motor 3 for the driven wheel is a direct drive motor that does not use a transmission. The electric motor 3 acts as an electric motor by supplying electric power, and also acts as a generator that converts the kinetic energy of the vehicle 30 into electric power.
Since the motor rotor 19 (FIG. 1) is attached to the inner ring 5 (FIG. 1), which is a hub ring, the motor 3 is rotationally driven when a current is applied to the motor 3, and the electric power regeneration is reversed. Sometimes regenerative power is obtained by loading the induced voltage.

<About the control system of the vehicle 30>
The host ECU 40 is a unit that performs integrated control of the vehicle 30 and includes a torque command generation unit 43. The torque command generating means 43 generates a torque command in accordance with operation amount signals respectively inputted from an accelerator operating means 56 such as an accelerator pedal and a brake operating means 57 such as a brake pedal. The vehicle 30 includes a motor generator 35b of the internal combustion engine 35a and the drive wheel as the main drive source 35, and because with the two electric motors 3, 3 for driving two driven wheels ₁₀ B, 10 _B, respectively, wherein Torque command distribution means 44 is provided in the host ECU 40 for distributing the torque command according to the rules determined for the drive sources 35a, 35b, 3, and 3.

  A torque command for the internal combustion engine 35 a is transmitted to the internal combustion engine control means 47 and used for valve opening control by the internal combustion engine control means 47. The torque command for the drive wheel side generator motor 35b is transmitted to the drive wheel side motor generator control means 48 and executed. Torque commands for the motors 3 and 3 on the driven wheel side are transmitted to the individual control means 39 and 39. A portion of the torque command distribution means 44 that outputs to the individual control means 39, 39 is referred to as an individual motor generator command means 45. The individual motor generator command means 45 also has a function of giving to the individual control means 39 a torque command that serves as a braking force command for the motor 3 to perform braking by regenerative braking in response to an operation amount signal of the brake operation means 57. Prepare.

  The individual control means 39 is an inverter device, an inverter 41 that converts DC power of the medium voltage battery 49 into a three-phase AC voltage, and a control unit 42 that controls the output of the inverter 41 by PWM control or the like according to the torque command or the like Have The inverter 41 includes a bridge circuit (not shown) using a semiconductor switching element and the like, and a charging circuit (not shown) that charges the regenerative power of the electric motor 3 to the medium voltage battery 49. The individual control means 39 is individually provided for the two electric motors 3 and 3, but may be configured to be housed in one casing and share the control unit 42 between the two individual control means 39 and 39. .

  FIG. 16 is a power system diagram as an example of a vehicle on which the vehicle system shown in FIG. 15 is mounted. In the example of the figure, a low voltage battery 50 and a medium power battery 49 are provided as batteries, and both the batteries 49 and 50 are connected via a DC / DC converter 51. There are two electric motors 3, but one is shown as a representative. The motor generator 35b on the drive wheel side in FIG. 15 is connected to the middle power system in parallel with the motor 3 on the driven wheel side, although not shown in FIG. A low voltage load 52 is connected to the low voltage system, and a medium voltage load 53 is connected to the medium voltage system. There are a plurality of low-voltage loads 52 and medium-voltage loads 53, but one is representatively shown.

  The low voltage battery 50 is a battery generally used for various automobiles as a power source for a control system or the like, and is, for example, 12V or 24V. As the low voltage load 52, there are basic parts such as a starter motor, lights, a host ECU 40 and other ECUs (not shown) of the internal combustion engine 35a. The low voltage battery 50 may be referred to as an auxiliary battery for electrical accessories, and the medium voltage battery 49 may be referred to as an auxiliary battery for an electric system.

  The medium voltage battery 49 is higher in voltage than the low voltage battery 50 and lower than a high voltage battery (100 V or more, for example, about 200 to 400 V) used in a strong hybrid vehicle or the like. A 48V battery that has a voltage that does not cause a problem and has recently been used in mild hybrids is preferable. The medium voltage battery 49 such as a 48V battery can be mounted relatively easily on a vehicle equipped with a conventional internal combustion engine, and as a mild hybrid, fuel efficiency can be reduced by power assist or regeneration using electric power.

  The medium voltage load 53 of the 48V system is the accessory part, such as a power assist motor, an electric pump, an electric power steering, a supercharger, and an air compressor, which are the electric motor 3 on the drive wheel side. By configuring the load by the accessories with a 48V system, the output of power assist is lower than that of high voltage (such as a strong hybrid vehicle of 100V or more), but the risk of electric shock to passengers and maintenance workers can be reduced. it can. Since the insulating coating of the electric wire can be thinned, the weight and volume of the electric wire can be reduced. In addition, since a large amount of electric power can be input / output with a current amount smaller than 12 V, the volume of the motor or generator can be reduced. From these things, it contributes to the fuel consumption reduction effect of a vehicle.

  This vehicle system is suitable as an accessory part of such a mild hybrid vehicle, and is applied as a power assist and power regeneration part. Conventionally, in mild hybrid vehicles, CMG, GMG, belt-driven starter motors (none of which are shown) may be employed, and these are all power assists for the internal combustion engine or the power unit. Or, since it is regenerated, it is affected by the efficiency of the transmission device and the speed reducer.

Since contrast to the vehicle system of this embodiment is mounted with respect to the driven wheels 10 _B, and the main drive source is disconnected such as an internal combustion engine 35a and the electric motor (not shown), the power regeneration In some cases, the kinetic energy of the vehicle body 1 can be used directly. Further, CMG, GMG, when mounting a belt driven starter motor, it is necessary to incorporate in consideration from the design stage of the vehicle 30, it is difficult be retrofitted, for this vehicle to fit in the driven wheel 10 in the _B The motor 3 of the system can be installed with the same man-hours as parts replacement even for a completed vehicle, and a 48V system can be configured even for a completed vehicle having only the internal combustion engine 35a. A vehicle equipped with the vehicle system of this embodiment may be equipped with another auxiliary drive motor generator 35b as in the example of FIG. At that time, the power assist amount and the regenerative power amount for the vehicle 30 can be increased, which further contributes to reduction of fuel consumption.

Figure 17 shows an example of the vehicle power system 1 was applied respectively to the driven wheels 10 _B which is a driving wheel 10 _A and a rear wheel is a front wheel according to any of the embodiments. The drive wheel _10A is driven through a clutch 36 and a speed reducer 7 by a main drive source 35 comprising an internal combustion engine. In this front-wheel drive vehicle, the support and the auxiliary drive of the drive wheels 10 _A and the driven wheels 10 _B, the power unit 1 is installed for a vehicle. Thus the vehicle power system 1, not only the driven wheels 10 _B, can also be applied to the drive wheels 10 _A.

  The vehicle system shown in FIG. 15 has a function of generating power, but may be a system that does not perform rotational driving by power feeding. This vehicle system is equipped with a generator-equipped wheel bearing device including a generator 3 that does not serve as a motor and a wheel bearing 2. This wheel bearing device with a generator has the same configuration as the vehicle power device of any of the embodiments except for a motor generator (motor) that also serves as a motor. In this case, a braking force can be generated by storing the regenerative power generated by the generator 3 in the medium voltage battery 49. The braking performance can be improved by using together with or using the mechanical brake operating means 57. Thus, when it restricts to the function to generate electric power, the individual control means 39 can be comprised not as an inverter apparatus but as an AC / DC converter apparatus (not shown). The AC / DC converter device has a function of charging the regenerative power of the generator 3 to the medium voltage battery 49 by converting a three-phase AC voltage to a DC voltage, and the control method is easier than an inverter. Miniaturization is possible.

  As mentioned above, although the form for implementing this invention based on embodiment was demonstrated, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 ... Vehicle power unit (wheel bearing device with generator)
2 ... Wheel bearing 3 ... Electric motor (generator)
4 ... Outer ring (fixed ring)
4a ... Body mounting surface 5 ... Inner ring (rotating wheel)
6 ... rolling elements 7 ... hub flange 10 B _... driven wheel 12 ... brake rotor 12b ... outer peripheral portion 18 ... stator 19 ... rotor (rotor)
22 ... Uneven portions 23 and 24 ... vent

Claims (8)

A wheel bearing having a fixed wheel and a hub flange, the wheel having a hub wheel and a rotating wheel that is rotatably supported by the fixed wheel via a rolling element, and a wheel of a vehicle and a brake rotor are attached to the hub flange;
A generator-equipped wheel bearing device comprising: a stator attached to the fixed wheel; and a generator having a rotor attached to the rotating wheel.
A portion of the brake rotor is located radially outward of the generator;
A generator-equipped wheel bearing device comprising a plurality of uneven portions on one or both of an inner peripheral surface of the brake rotor and an outer peripheral surface of the generator.   2. The wheel bearing device with a generator according to claim 1, wherein the generator is an outer rotor motor in which the stator is located on an outer periphery of the wheel bearing and the rotor is located radially outward of the stator. A generator-equipped wheel bearing device in which the uneven portion is provided on one or both of an inner peripheral surface of the brake rotor and an outer peripheral surface of the rotor.   The wheel bearing device with a generator according to claim 1 or 2, wherein the brake rotor is provided with a vent hole.   The wheel bearing device with a generator according to any one of claims 1 to 3, wherein the uneven portion has a fin shape.   The wheel bearing device with a generator according to any one of claims 1 to 4, wherein the wheel bearing supports a driven wheel that is mechanically disconnected from a main drive source of the vehicle. This is a wheel bearing device with a generator.   The wheel bearing device with a generator according to claim 5, wherein the generator is a driving assist motor generator capable of rotationally driving the driven wheel by being supplied with electric power.   7. The wheel with generator according to claim 1, wherein the generator is a motor generator capable of rotationally driving the wheel by being supplied with power. Bearing device. A wheel bearing having a fixed wheel and a hub flange, the wheel having a hub wheel and a rotating wheel that is rotatably supported by the fixed wheel via a rolling element, and a wheel of a vehicle and a brake rotor are attached to the hub flange;
In a vehicle power device comprising: a stator attached to the fixed wheel; and an electric motor having a motor rotor attached to the rotating wheel.
A portion of the brake rotor is located radially outward of the electric motor;
A vehicle power unit comprising a plurality of concave and convex portions on one or both of an inner peripheral surface of the brake rotor and an outer peripheral surface of the electric motor.

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