JP4486443B2 - Wheel drive device for vehicle - Google Patents

Description

  The present invention relates to an improved technique for a vehicle wheel drive device in which an electric motor, a so-called in-wheel motor, is arranged inside a rim of a vehicle wheel (wheel).

In recent years, in order to simplify the power transmission system from the power source to the wheel and increase the transmission efficiency in the vehicle, development of a technology for arranging an in-wheel motor as a driving source inside the rim of the wheel has been advanced. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 6-144021 (FIG. 1)

A conventional vehicle wheel drive device disclosed in Patent Document 1 will be described with reference to FIG.
FIG. 9 is a schematic diagram of a conventional vehicle wheel drive device (prior art). In a conventional vehicle wheel drive device 200, an axle 202 is fixed to a body frame 201, an inner stator 203 is provided on the axle 202, and an outer rotor 204 is rotatably attached to the axle 202 so as to surround the inner stator 203. A wheel 205 is provided. The in-wheel motor 210 includes an inner stator 203 having a magnet 211 and an outer rotor 204 having a coil 212.

  Further, the vehicle wheel drive device 200 includes a thermoelectric element 221 that receives heat from the in-wheel motor 210 and generates a thermoelectromotive force, and an electric fan 222 that blows air toward the in-wheel motor 210. When the in-wheel motor 210 is hot, not only when the vehicle is running but also when the vehicle is stopped, the thermoelectric element 221 generates a thermoelectromotive force according to the amount of heat, and the thermoelectric force causes the electric fan 222 to move. By rotating, the in-wheel motor 210 can be air-cooled.

  By the way, in order to enhance the cooling effect of cooling the in-wheel motor 210, the air blowing amount of the electric fan 222 may be increased. However, the thermoelectromotive force generated by the thermoelectric element 221 that receives heat from the wheel 205 is relatively small. There is a limit to increasing the amount of air blown by the electric fan 222 rotating by the thermoelectromotive force. In addition, the device for cooling the in-wheel motor 210 requires the thermoelectric element 221, the motor 223 of the electric fan 222, the wiring between the thermoelectric element 221 and the motor 223, etc., and must be complicated. .

  The present invention provides a vehicle wheel drive device in which an in-wheel motor for driving a wheel is incorporated in a rim of the wheel, and provides a technique for further enhancing the cooling effect for cooling the in-wheel motor with a simple configuration. Is an issue.

  The invention according to claim 1 is a vehicle wheel drive device in which an in-wheel motor for driving a wheel and a disc brake for braking the wheel are incorporated in a rim of the wheel, wherein the in-wheel motor is disposed inside the rim. In a vehicle wheel drive device comprising a fixed cylindrical outer rotor and a cylindrical inner stator that is disposed inside the outer rotor and connected to the vehicle body side, a disc-shaped brake mounted on the outer rotor is a hollow disc-shaped brake. The brake disk includes a disc and a caliper attached to the inner stator, and the brake disc includes a blowing fin for blowing air to the in-wheel motor.

Furthermore, the invention according to claim 1 is directed to a power generation fan that rotates by receiving air from a blower fin on a brake disk, and a motor generator that is driven by the power generation fan to generate power and also has a function of an electric motor. And a battery for storing electric power generated by the motor generator.

The invention according to claim 2 is a configuration in which the motor generator is supplied with electric power from the battery and drives the power generation fan when the brake disk rotates at a low speed, and the power generation fan is driven by at least the motor generator. It is also characterized in that it also serves as an air cooling fan that air-cools the in-wheel motor.

The invention according to claim 3 is a vehicle wheel drive device incorporating an in-wheel motor for driving the wheel and a disc brake for braking the wheel in the rim of the wheel and concentrically with the rim,
The in-wheel motor is a vehicle wheel drive device including a cylindrical outer rotor fixed inside the rim, and a cylindrical inner stator disposed inside the outer rotor and connected to the vehicle body side.
The disc brake is composed of a brake disc attached to the outer rotor and a caliper attached to the inner stator.
The brake disc includes a flange attached to an outer rotor-side outer end portion of the outer rotor, a connecting portion extending outward from the flange in the vehicle width direction, and a connecting portion extending from the outer end in the vehicle width direction to a radially inward direction. It consists of a hollow disk-shaped disk part that extends and brakes,
Furthermore, the brake disc has a function of an electric motor that is capable of generating electric power by being driven by the power generation fan, and a power generation fan that is rotated by receiving air from the air flow fin. A motor generator and a battery for storing electric power generated by the motor generator;
The air blowing fins are arranged on the disk part side of the brake disk,
The motor generator is arranged between the flange and the air blowing fin, and is configured to receive the power of the battery and drive the power generating fan when the brake disk rotates at a low speed.
The power generation fan is disposed between the flange and the blower fin and serves also as an air cooling fan that cools the in-wheel motor at least when driven by the motor generator.

In the invention according to claim 1, since the air blowing fin is provided on the brake disk that rotates together with the outer rotor of the in-wheel motor, the air blowing fin also rotates when the in-wheel motor rotates and cools by sending air to the in-wheel motor. be able to. As a result, the in-wheel motor can be cooled while traveling the vehicle. In addition, the higher the in-wheel motor rotates, the more the air volume of the blowing fins can be increased. Therefore, the cooling effect for cooling the in-wheel motor is further enhanced.
Furthermore, the device for cooling the in-wheel motor can be simply configured by simply providing a blower fin on the brake disc of a disc brake incorporated to brake the wheel.

Furthermore, in the invention according to claim 1, when the heat generated by the disc brake is transmitted from the disc surface to the brake disc, the heat can be dissipated to the outside air through the blowing fins. As a result, it is possible to suppress the heat generated by the disc brake from being transmitted to the in-wheel motor.
Further, when the heat generated by the in-wheel motor is transmitted from the outer rotor to the brake disk, the heat can be dissipated to the outside air through the blowing fins. As a result, heat generated by the in-wheel motor can be prevented from being transmitted to the disk surface.
In this way, the heat dissipation of the disc brake and the in-wheel motor can be further enhanced.

Further, in the invention according to claim 1 , in addition to the blowing fins, the brake disk is provided with a power generation fan that rotates by receiving air blown from the blower fins, and a function of the electric motor driven by the power generation fan and capable of generating power. The motor generator and the battery for storing the electric power generated by the motor generator are provided. It can generate electricity and charge the battery. Therefore, it is possible to efficiently use the air blown from the blower fins.

In the invention according to claim 2 , when the brake disk rotates at a low speed, the motor generator supplied with power from the battery drives the power generation fan so that the in-wheel motor is air-cooled by the power generation fan. is there.
When the wheel and the in-wheel motor rotate at a low speed, the brake disc and the air blowing fin also rotate at a low speed. As a result, the amount of air blown from the blowing fins is reduced, so that the air cooling effect is lowered.
On the other hand, according to the second aspect of the present invention, the in-wheel motor can be air-cooled by the power generation fan driven by the motor generator without depending on the air cooling by the blowing fins when the brake disk rotates at a low speed. . For example, the in-wheel motor can be sufficiently cooled even when the in-wheel motor rotates at a low speed as when traveling at a low speed on an uphill.
In addition, a battery that is a power source different from the power source for the in-wheel motor is provided, and the battery is charged by effectively using the ventilation of the blowing fins, and the generator fan is driven by the charged power. It is what. For this reason, the power of the power source for the in-wheel motor can be effectively used only for the in-wheel motor.

In the invention according to claim 3 , since the air blowing fin is provided on the brake disk that rotates together with the outer rotor of the in-wheel motor, the air blowing fin also rotates when the in-wheel motor rotates, and the air is blown to the in-wheel motor to be cooled. be able to. As a result, the in-wheel motor can be cooled while traveling the vehicle. In addition, the higher the in-wheel motor rotates, the more the air volume of the blowing fins can be increased. Therefore, the cooling effect for cooling the in-wheel motor is further enhanced.
Furthermore, the device for cooling the in-wheel motor can be simply configured by simply providing a blower fin on the brake disc of a disc brake incorporated to brake the wheel.

Further, in the invention according to claim 3 , when the heat generated in the disc brake is transmitted from the disc surface to the brake disc, the heat can be dissipated to the outside air through the blowing fins. As a result, it is possible to suppress the heat generated by the disc brake from being transmitted to the in-wheel motor.
Further, when the heat generated by the in-wheel motor is transmitted from the outer rotor to the brake disk, the heat can be dissipated to the outside air through the blowing fins. As a result, heat generated by the in-wheel motor can be prevented from being transmitted to the disk surface.
In this way, the heat dissipation of the disc brake and the in-wheel motor can be further enhanced.

Furthermore, in the invention according to claim 3 , in addition to the blowing fins, the brake disk is provided with a power generating fan that rotates by receiving air blown from the blowing fins, a function of the electric motor driven by the power generating fan and capable of generating power. The motor generator and the battery for storing the electric power generated by the motor generator are provided. It can generate electricity and charge the battery. Therefore, it is possible to efficiently use the air blown from the blower fins.

Furthermore, in the invention according to claim 3 , when the brake disk rotates at a low speed, the motor generator supplied with electric power from the battery drives the power generation fan so that the in-wheel motor is air-cooled by the power generation fan. It is.
When the wheel and the in-wheel motor rotate at a low speed, the brake disc and the air blowing fin also rotate at a low speed. As a result, the amount of air blown from the blowing fins is reduced, so that the air cooling effect is lowered.
On the other hand, according to the third aspect of the present invention, the in-wheel motor can be air-cooled by the power generation fan driven by the motor generator without depending on the air cooling by the blowing fins when the brake disk rotates at a low speed. . For example, the in-wheel motor can be sufficiently cooled even when the in-wheel motor rotates at a low speed as when traveling at a low speed on an uphill.
In addition, a battery that is a power source different from the power source for the in-wheel motor is provided, and the battery is charged by effectively using the ventilation of the blowing fins, and the generator fan is driven by the charged power. It is a thing. For this reason, the power of the power source for the in-wheel motor can be effectively used only for the in-wheel motor.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. Note that “front”, “rear”, “left”, “right”, “upper”, and “lower” follow the direction seen from the driver.
FIG. 1 is a configuration view of a vehicle equipped with a vehicle wheel drive device according to the present invention as viewed from the rear, and shows the configuration of a suspension 20, a wheel 30, and a vehicle wheel drive device 40 on the right side. FIG. 2 is a cross-sectional view of the suspension, the wheel, and the vehicle wheel drive device according to the present invention, and is shown corresponding to FIG.
Since the suspension 20, the wheel 30, and the vehicle wheel drive device 40 on the left side have the same configuration as that on the right side, illustration and description thereof are omitted.

As shown in FIG. 1, a vehicle 10 is a four-wheel electric vehicle in which a wheel 30 is suspended from a vehicle body 11 by a suspension 20 and is equipped with a vehicle wheel drive device 40 and includes two wheels at the front and rear. .
The vehicle wheel drive device 40 has a configuration in which an in-wheel motor 50 that is a drive source for driving the wheel 30 and a disc brake 60 that brakes the wheel 30 are incorporated in the rim 31 (inward of the diameter) of the wheel 30. .
Hereinafter, the suspension 20, the wheel 30, and the vehicle wheel driving device 40 will be described in detail.

  The suspension 20 includes an upper upper arm 21 and a lower lower arm 22 that are attached to the vehicle body 11 so as to be able to swing up and down, a cushion 23 that is attached between the lower arm 22 and the damper housing 12 on the vehicle body side, and upper and lower arms 21 and 22. This is a suspension device for suspending a wheel 30 on the vehicle body 11 with the upper and lower joints 24 and 25 at the front ends thereof as main components.

The vehicle wheel drive device 40 suspends the in-wheel motor 50 from the vehicle body 11 via the upper and lower joints 24 and 25, and attaches the wheel 30 to the in-wheel motor 50. The in-wheel motor 50 concentric with the wheel 30 is arranged. The in-wheel motor 50 is a hollow electric motor that is concentric with the rotation center RC of the wheel 30.
Since it is such a vehicle wheel drive device 40, the space around the rotation center RC of the wheel 30 can be used effectively.

  As shown in FIG. 2, the wheel 30 is a wheel including a cylindrical rim 31, a tire 32 attached to the rim 31, and a hollow disk-like disk 33 attached to the inner peripheral surface 31 a of the rim 31. The disk 33 is arranged at the approximate vehicle width center of the rim 31.

  As will be described in detail later, the in-wheel motor 50 includes an inner stator 53 that is a non-rotating member, and extends from the inner stator 53 to the inner side In (the left side in FIG. 2), an upper upper stay 53a and a lower lower stay 53b. Is provided. That is, the inner stator 53 also serves as a knuckle.

The upper stay 53a extends toward the inner side In in the vehicle width direction, and can be connected to the tip of the upper arm 21 via the upper joint 24 by attaching the upper joint 24 to the tip. On the other hand, the lower stay 53b extends toward the inner side In in the vehicle width direction, and can be connected to the front end of the lower arm 22 via the lower joint 25 by attaching the lower joint 25 to the front end. The upper and lower joints 24 and 25 are, for example, ball joints.
A straight line Ki passing between the centers of the upper and lower joints 24 and 25 is a kingpin axis of the suspension 20 (a kingpin centerline, also referred to as a virtual kingpin axis).

FIG. 3 is a cross-sectional view of the lower half of the vehicle wheel drive device according to the present invention and is shown corresponding to FIG.
As shown in FIGS. 2 and 3, the in-wheel motor 50 is arranged inside the rim 31 (inwardly in the dia.) And close to the vehicle width direction inside In (left side in FIGS. 2 and 3) suspended by the suspension 20. It is a thing. Such an in-wheel motor 50 is disposed inside the outer rotor 51, a cylindrical outer rotor 51 fixed inside the rim 31, a plurality of permanent magnets 52 attached to the inner peripheral surface of the outer rotor 51, and the like. A cylindrical inner stator 53 connected to the vehicle body 11 side (see FIG. 1) and a plurality of electric elements 54 attached to the outer peripheral surface of the inner stator 53 are provided.

The outer rotor 51 on the rotation side and the inner stator 53 on the non-rotation side are concentric with the rotation center RC of the wheel 30. The electric element 54 includes an iron core, a coil bobbin, and a winding.
The outer rotor 51 is a rotating member that is fixed inside the rim 31 by bolting the disk 33 to the end portion 51a of the vehicle width direction outer side Ou. The inner stator 53 is an outer peripheral surface, and is a fixing member that supports the inner peripheral surface of the outer rotor 51 through bearings 55 and 56 while allowing the inner rotor 53 to rotate and restrict axial movement.

Next, the disc brake 60 will be described.
As shown in FIG. 2, since the in-wheel motor 50 is arranged inside the rim 31 so as to be closer to the vehicle width direction inner side In, an empty space Sp is formed inside the rim 31 and outside the vehicle width direction Ou. The disc brake 60 is arranged in this empty space Sp.

The disc brake 60 includes a brake disc 61 attached to the end 51a of the outer rotor 51 on the outer side Ou in the vehicle width direction, and a caliper 71 attached to the end 53c of the inner stator 53 on the outer side Ou in the vehicle width direction. This is a pressure type or pneumatic type brake mechanism.
The brake disk 61 is a rotating member having a hollow disk shape as a whole, and is concentric with the rotation center RC of the wheel 30.

FIG. 4 is an exploded view of the vehicle wheel drive device according to the present invention, and shows the lower half of the vehicle wheel drive device 40 corresponding to FIG.
As shown in FIGS. 3 and 4, the brake disc 61 includes a hollow disc-like flange 62 that is directly attached to an end (end surface) 51 a on the outer side Ou in the vehicle width direction of the outer rotor 51, and an inner periphery of the flange 62. One-piece product comprising a cylindrical connecting portion 63 extending outward in the width direction O, and a hollow disc-shaped disc portion 64 that extends radially inward from the end of the connecting portion 63 on the outer side Ou in the vehicle width direction and is braked. It is.

  The flange 62 is a flat plate that is attached to the end portion (end surface) 51a of the outer rotor 51 and is directly attached by a plurality of bolts 67. The connecting portion 63 is a relatively thin and short cylinder. The disk portion 64 is a flat plate having flat disk surfaces 64a and 64a on both side surfaces.

As described above, the brake disc 61 is configured such that the disc portion 64 is disposed at a position separated from the flange 62 by the separation distance Lc on the outer side Ou (right side in FIG. 4) in the vehicle width direction. The disk surfaces 64 a and 64 a are parallel to the flange 62.
In the brake disc 61, the entire disc portion 64 or only the contact portion braked by the caliper 71 in the disc portion 64 is made of a material having good wear resistance and heat resistance such as steel, and the remaining portion is made of aluminum. It is particularly preferable to use a lightweight material having good thermal conductivity such as an alloy.

  On the other hand, as shown in FIG. 2, the caliper 71 is attached to the end portion (end surface) 53 c of the inner stator 53, and the piston 73 in the body 72 is operated by the braking pressure. The disc surfaces 64a and 64a are pressed and braking control is performed by the frictional force.

  Such a caliper 71 has an opening 75 into which the disk surfaces 64a and 64a of the brake disk 61 are rotatable. The opening 75 is directed outward in the radial direction of the wheel 30. Accordingly, the body 72 has a U-shaped cross-sectional view with the opening 75 facing the outer side in the radial direction of the wheel 30. Since the opening 75 is directed outward in the radial direction of the wheel 30, the caliper 71 can be disposed on the wheel center RC <b> 1 side with respect to the inner stator 53. The brake disc 61 is disposed on the radially outer side with respect to the caliper 71.

Incidentally, the brake disk 61 includes a motor cooling device 80 as shown in FIGS. FIG. 5 is a schematic view of a motor cooling device according to the present invention.
As shown in FIGS. 3 and 5, the motor cooling device 80 includes a blower fan 90 that blows air to the in-wheel motor 50, a power generation fan 100 that rotates by receiving air blown from the blower fan 90, and the power generation fan 100. A motor generator 110 that is driven by the motor generator 110 and has a function of an electric motor; a battery 121 that stores electric power generated by the motor generator 110; a rotation sensor 122 that detects a rotation speed of the brake disc 61; A temperature sensor 123 that detects the temperature of the motor 50, and a control unit 124 that controls the motor generator 110 in accordance with the rotation sensor 122 and the detection signal of the temperature sensor 123 are provided.

The control unit 124 generates a control signal in response to detection signals from the rotation sensor 122 and the temperature sensor 123, and receives the control signal from the control unit 125 to switch between the charging mode and the power supply mode, thereby switching the motor generator 110. And a switching unit 126 to be controlled.
The charging mode is a mode in which the charging circuit from the motor generator 110 to the battery 121 is switched to a connected state and the motor generator 110 performs a function as a generator. On the other hand, in the power supply mode, the power supply circuit from the battery 121 to the motor generator 110 is connected, and the motor generator 110 is switched so as to function as a motor. This is the mode to control.

Therefore, the motor generator 110 receives (1) the function of the generator that is driven by the power generation fan 100 to generate power and charges the battery 121 and (2) the power of the battery 121 by the switching operation of the switching unit 126. Thus, the operation of the electric motor that drives the power generation fan 100 is switched.
Hereinafter, the motor cooling device 80 will be described in detail.

FIG. 6 is a perspective view of main parts of the blower fan and the power generation fan according to the present invention.
As shown in FIGS. 3 and 6, the blower fan 90 includes a ring-shaped hub 91, a hollow disk-shaped flange 92 extending radially inward from the hub 91, and a plurality of pitches provided on the outer peripheral surface of the hub 91 at a constant pitch. It is an axial flow fan which integrally formed the fin 93 ... for ventilation, and the cyclic | annular straightening cover 94 surrounding the outer periphery of the fin 93 ... for ventilation.
The rectifying cover 94 is a member that suppresses the air sent by the blowing fins 93... From being radiated outward by the centrifugal force when the blowing fan 90 rotates.

  The blower fan 90 can be attached to the brake disc 61 by removably stopping the flange 92 on the disc surface 64a of the outer side Ou of the disc portion 64 with a plurality of bolts 95. In this way, the brake disc 61 was provided with the blowing fins 93. The blowing fins 93 are arranged on the disc part 64 side of the brake disc 61.

  As shown in FIGS. 3 and 4, the motor generator 110 is attached to the outer peripheral surface of the connecting portion 63 of the brake disc 61 and receives the electric power of the battery 121 when the brake disc 61 rotates at a low speed to drive the power generation fan 100. It is a configuration. By doing in this way, the motor generator 110 was arrange | positioned between the flange 62 of the brake disc 61, and the fan 90 for blowing (namely, fin 93 for ventilation).

Specifically, the motor generator 110 is disposed inside the outer rotor 111, a cylindrical outer rotor 111 disposed inside the rim 31, a plurality of permanent magnets 112 attached to the inner peripheral surface of the outer rotor 111, and the outer rotor 111. The cylindrical inner stator 114 attached to the outer peripheral surface of the connection part 63 via the heat insulating ring 113, and the several electric element 115 ... attached to the outer peripheral surface of the inner stator 114 are provided.
The inner stator 114 is an outer peripheral surface, and is a fixing member that supports the inner peripheral surface of the outer rotor 111 via bearings 116 and 116 so as to be able to rotate and restrict axial movement.

As shown in FIGS. 3 and 6, the power generation fan 100 also serves as an air cooling fan that cools the in-wheel motor 50 at least when driven by the motor generator 110.
Such a power generation fan 100 includes a plurality of power generation fins 101 provided on the outer peripheral surface of the outer rotor 111 in the motor generator 110 at a constant pitch. In this way, the power generation fan 100 is disposed between the flange 92 of the brake disk 61 and the blower fan 90 (that is, the blower fins 93...).

  That is, by making the power generation fan 100 adjacent to the blower fan 90 and making the power generation fins 101... Face the blower fins 93. I tried to fit. The influencing relationship will be described next.

FIGS. 7A and 7B are configuration diagrams and operation diagrams for explaining the interrelationship between the blower fan and the power generation fan according to the present invention. The blower fan 90 and the power generation fan 100 are viewed from the outer peripheral side. A part of it was developed.
As shown in FIGS. 6 and 7 (a), each of the air blowing fins 93 of the air blowing fan 90 has a substantially arc shape protruding in the direction opposite to the white arrow Ru side, and the vehicle width. From the direction outer side Ou to the vehicle width direction inner side In, it exhibits a cross-sectional shape inclined in the direction opposite to the white arrow Ru side.
On the other hand, each of the power generation fins 101 of the power generation fan 100 has a substantially arc-shaped cross-sectional shape that protrudes toward the white arrow Ru side, and further from the vehicle width direction outer side Ou toward the vehicle width direction inner side In. The cross-sectional shape is inclined in the direction opposite to the white arrow Ru side.

  The white arrow Ru side means the counterclockwise direction in FIG. Further, the vehicle width direction inner side In is on the in-wheel motor 50 side as shown in FIG. 3, and the vehicle width direction outer side Ou is on the side opposite to the in-wheel motor 50.

In FIG. 7A, when the power generation fan 100 is stopped and the blower fan 90 is rotated in the direction of the white arrow Ru, the outside air (air) is indicated by the blower fins 93. .. is sucked and sent to the adjacent power generation fins 101. The sent outside air hits each of the power generating fins 101... As indicated by an arrow W2 and flows out inward in the vehicle width direction as indicated by an arrow W3 while rotating in the direction indicated by an outlined arrow Ru.
That is, the impact force when the air sent from the blowing fins 93... Hits the power generation fins 101... As shown by the arrow W2 and the vehicle width from the power generation fins 101. The combined force of the reaction force when it flows out in the direction inner In and the rotational force that turns the power generation fan 100 turns.

  Thus, when the blower fan 90, that is, the blower fins 93... Rotate in the direction of the hollow arrow Ru, the in-wheel motor 50 (see FIG. 3) and the power generation fan 100 can be turned.

  On the other hand, in FIG. 7B, when the power generation fan 100 is rotated in a direction Ruc opposite to the outlined arrow Ru direction while the blower fan 90 is stopped or rotating at a low speed, the input shown in FIG. The inside air (air) on the wheel motor 50 side is sucked by the power generation fins 101... And sent to the adjacent blower fins 93. The sent inside air passes between the air blowing fins 93 as indicated by an arrow W5, and then is sent to the vehicle width direction outer side Ou and flows out as indicated by an arrow W6.

When the power generation fan 100, that is, the power generation fins 101, rotates in the reverse direction Ruc, the in-wheel motor 50 (see FIG. 3) is blown from the vehicle width direction inner side In to the vehicle width direction outer side Ou. ) Can be cooled.
Since the blower fan 90 is connected to the wheel 30 as shown in FIG. 3, the blower fan 90 is not rotated by the rotational force generated by the blowing of the power generation fan 100.

7 and the power generation fins 101... May be opposite to the direction shown in FIG. That is, the inclination direction of each blowing fin 93... And each power generation fin 101... May be inclined toward the white arrow Ru side from the vehicle width direction outer side Ou toward the vehicle width direction inner side In. .
In such a case, the air flow directions W1 to W6 are opposite to the directions shown in FIG. That is, when the blowing fins 93... Rotate in the direction of the hollow arrow Ru, the air can be blown from the vehicle width direction inner side In to the vehicle width direction outer side Ou. On the other hand, when the power generation fins 101... Rotate in the reverse direction Ruc, the air can be blown from the vehicle width direction outer side Ou to the vehicle width direction inner side In.

As is apparent from the above description, as shown in FIG. 2, the blower fan 90, the power generation fan 100, and the motor generator 110 are substantially concentric with respect to the rotation center RC of the wheel 30, and an empty space in the rim 31. It is arranged in Sp.
The center of the power generation fan 100 is preferably slightly offset from the center of the blower fan 90. The reason is that if the offset is made, the power generation fan 100 is always continuously rotated in the same direction by the air blown from the blower fan 90 to the power generation fan 100, thereby preventing reverse rotation.

  By the way, as shown in FIG. 4, the battery 121, the rotation sensor 122, and the control means 124 are assembled as a single unit by being attached to the substrate 127, and the substrate 127 is attached to the disk surface 64a on the disk surface 64a by screws 128 inside the connecting portion 63. It is attached to the brake disc 61 by stopping it so as to be removable.

As shown in FIGS. 3 to 5, the rotation sensor 122 is a detection member that detects a relative rotation speed of the brake disc 61 with respect to the inner stator 53 of the in-wheel motor 50, for example. The combined structure of the rotation sensor 122 and the gear 131 constitutes the rotation detection device 132.
The gear 131 is a concavity and convexity of a constant pitch provided concentrically with the rotation center RC of the wheel 30 over the entire end face 53c of the inner stator 53 on the outer side Ou in the vehicle width direction. The tooth tip surface of the gear 131 is parallel to the end surface 53c.
Therefore, the rotation sensor 122 is arranged with the detection part facing the tooth tip surface of the gear 131, and can detect the relative rotational speed of the brake disk 61 with respect to the inner stator 53 electromagnetically or optically.

  As shown in FIGS. 3 and 4, the temperature sensor 123 is attached to the flange 62 of the brake disk 61 and inserted into the insertion hole 51 b opened in the end (end surface) 51 a of the outer rotor 51, for example, so that the in-wheel. The temperature of the motor 50 can be detected.

  Next, a control flow when the control unit 125 (see FIG. 5) having the above configuration is a microcomputer will be described based on FIG. 8 with reference to FIG. In the figure, STxx indicates a step number. Step numbers that are not specifically described proceed in numerical order. In this control flow, for example, control is started by turning on a power switch (not shown) of the in-wheel motor 50, and control is ended by turning off the power switch.

FIG. 8 is a control flowchart of the control unit according to the present invention.
ST01: The relative rotational speed Nd of the brake disc 61 with respect to the inner stator 53 of the in-wheel motor 50 is read. The current rotation speed Nd can be detected by the rotation sensor 122 of FIG. The rotational speed Nd is the same as the rotational speed of the wheel 30.

ST02: Check whether the current rotational speed Nd exceeds a preset reference rotational speed Ns (Nd> Ns). If YES, the process proceeds to ST03, and if NO, the process proceeds to ST04.
In the case of YES, the brake disc 61 is rotating at a medium speed or a high speed, and as a result, the in-wheel motor 50 is cooled only by the blowing by the blowing fan 90, that is, the blowing fins 93 ... Is determined to be sufficient.
On the other hand, in the case of NO, since the reference rotational speed Ns is not exceeded, the brake disk 61 rotates at a low speed (including stop). As a result, the blower fan 90, that is, the blower fins 93. It is determined that the amount of air flow is insufficient to cool the in-wheel motor 50 only by the air flow.

  ST03: A charge switching control signal is issued and the switching unit 126 is switched to the charging mode, so that the charging circuit from the motor generator 110 to the battery 121 is connected and the motor generator 110 functions as a generator. After switching, return to ST01. As a result, the in-wheel motor 50 can be cooled and the power generation fan 100 can be turned by blowing air from the blowing fan 90, that is, the blowing fins 93. The motor generator 110 driven by the power generation fan 100 starts power generation and charges the battery 121.

ST04: By issuing a power supply switching control signal and switching the switching unit 126 to the power supply mode, the power supply circuit from the battery 121 to the motor generator 110 is brought into a connected state, and the motor generator 110 is used as a motor. Switch to function.
ST05: The temperature Th of the in-wheel motor 50 is read. The current temperature Th can be detected by the temperature sensor 123 of FIG.
ST06: It is checked whether or not the current temperature Th exceeds a preset reference temperature Ts (Th> Ts). If YES, the process proceeds to ST07, and if NO, the process proceeds to ST08.

ST07: Since the temperature Th of the in-wheel motor 50 is high, a high-speed rotation control signal is issued and the motor generator 110 is controlled to rotate at a constant high-speed rotation, and then the process returns to ST01. As a result, the amount of air blown by the power generation fan 100 increases and the in-wheel motor 50 can be sufficiently cooled.
ST08: Since the temperature Th of the in-wheel motor 50 is relatively low, a low-speed rotation control signal is issued to rotate the motor generator 110 to a constant low-speed rotation, and then the process returns to ST01. As a result, the amount of air blown by the power generation fan 100 decreases. The relatively low temperature in-wheel motor 50 can be sufficiently cooled.

  Thus, when the in-wheel motor 50 and the brake disc 61 are rotating at a low speed (including stoppage), the motor generator 110 is rotated by the electric power from the battery 121, and the power generation fan 100 is at the temperature of the in-wheel motor 50. The in-wheel motor 50 can be cooled so that it may become an optimal temperature state by sending the ventilation volume according to Th.

The above description is summarized as follows.
That is, in the present invention, as shown in FIG. 2, since the brake disk 61 that rotates together with the outer rotor 51 of the in-wheel motor 50 is provided with the blowing fins 93..., When the in-wheel motor 50 rotates, the blowing fins 93. .. Can also be rotated and blown to the in-wheel motor 50 for cooling. As a result, the in-wheel motor 50 can be cooled while traveling the vehicle 10 (see FIG. 1). Moreover, the air volume of the blowing fins 93 can be increased as the in-wheel motor 50 rotates at higher speed. Therefore, the cooling effect for cooling the in-wheel motor 50 is further enhanced.

  Furthermore, the device for cooling the in-wheel motor 50 can be simply configured by simply providing the air blow fins 93... On the brake disc 61 of the disc brake 60 incorporated to brake the wheel 30.

Furthermore, in the present invention, when the heat generated in the disc brake 60 is transmitted from the disc surfaces 64a and 64a to the brake disc 61, the heat can be dissipated to the outside air through the blowing fins 93. As a result, it is possible to suppress the heat generated by the disc brake 60 from being transmitted to the in-wheel motor 50.
Further, when the heat generated by the in-wheel motor 50 is transmitted from the outer rotor 51 to the brake disk 61, the heat can be dissipated to the outside air through the blowing fins 93. As a result, heat generated by the in-wheel motor 50 can be prevented from being transmitted to the disk surfaces 64a and 64a.
In this way, the heat dissipation of the in-wheel motor 50 and the disc brake 60 can be further enhanced.

  Further, in the present invention, the brake disk 61 is driven by the power generation fan 100 that rotates by receiving air from the air blow fins 93. Since the motor generator 110 that can generate electric power and also has the function of the motor and the battery 121 that stores the electric power generated by the motor generator 110 are provided, the in-wheel motor 50 is blown by blowing from the blowing fins 93. The power generation fan 100 is rotated to generate power with the motor generator 110 and the battery 121 can be charged. Therefore, it is possible to efficiently use the air blown from the blower fins 93.

Further, in the present invention, when the brake disk 61 rotates at a low speed, the motor generator 110 supplied with power from the battery 121 drives the power generation fan 100 so that the in-wheel motor 50 is air-cooled by the power generation fan 100. It is what.
When the wheel 30 and the in-wheel motor 50 are rotated at a low speed, the brake disc 61 and the blowing fins 93 are also rotated at a low speed. As a result, the amount of air blown by the blower fins 93.

  On the other hand, according to the present invention, the in-wheel motor 50 is air-cooled by the power generation fan 100 driven by the motor generator 110 without depending on air cooling by the blowing fins 93. can do. For example, the in-wheel motor 50 can be sufficiently cooled even when the in-wheel motor 50 is rotating at a low speed as when traveling at a low speed on an uphill.

  In addition, the battery 121 is provided as a power source different from the power source for the in-wheel motor 50, and the battery 121 is charged by effectively using the air blown from the blower fins 93. The fan 100 is driven. For this reason, the power of the power source for the in-wheel motor 50 can be effectively used only for the in-wheel motor 50.

  Further, when the wheel 30 is braked by the disc brake 60, the brake disc 61 together with the in-wheel motor 50 also stops after rotating at a low speed. At this time, when the heat generated in the disc brake 60 is transmitted from the disc surfaces 64a and 64a to the blower fins 93 through the brake disc 61, the blower fins 93.・ Can be cooled. As a result, it is possible to suppress the heat generated by the disc brake 60 from being transmitted to the in-wheel motor 50.

  In the embodiment of the present invention, the blower fins 93 are not limited to the configuration provided to be detachable directly to the brake disc 61, and for example, are configured to be integrated with the brake disc 61. There may be. Moreover, the position of the fins 93 for blowing with respect to the brake disc 61 is arbitrary.

  The vehicle wheel drive device 40 of the present invention can simplify the power transmission system from the power source to the wheel 30 by disposing the in-wheel motor 50 as the power source inside the rim 31 of the wheel 30. Therefore, it is suitable for an electric vehicle.

It is the block diagram which looked at the vehicle carrying the vehicle wheel drive device which concerns on this invention from back. It is sectional drawing of the suspension which concerns on this invention, a wheel, and the wheel drive device for vehicles. It is sectional drawing of the lower half of the vehicle wheel drive device which concerns on this invention. It is an exploded view of the wheel drive device for vehicles concerning the present invention. It is a schematic diagram of the motor cooling device which concerns on this invention. It is a principal part perspective view of the fan for ventilation which concerns on this invention, and the fan for electric power generation. It is a block diagram and action figure explaining the mutual relationship of the fan for ventilation which concerns on this invention, and the fan for electric power generation. It is a control flowchart of the control part which concerns on this invention. FIG. 9 is a schematic view of a conventional vehicle wheel drive device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Vehicle body, 20 ... Suspension, 30 ... Wheel, 31 ... Rim, 40 ... Vehicle wheel drive device, 50 ... In-wheel motor, 51 ... Outer rotor, 51a ... End of outer rotor direction Ou among outer rotors , 53... Inner stator, 53 c... End of the inner stator in the vehicle width direction Ou, 60... Disc brake, 61... Brake disc, 62 ... flange, 63 ... connecting portion, 64 ... disc portion, 71. DESCRIPTION OF SYMBOLS 80 ... Motor cooling device, 90 ... Fan for ventilation, 93 ... Fin for ventilation, 100 ... Fan for electric power generation, 101 ... Fin for electric power generation, 110 ... Motor generator, 121 ... Battery, 122 ... Rotation sensor, 123 ... Temperature sensor, 125: control unit, 126: switching unit, 131: gear, In: vehicle width direction inner side In, Ou: vehicle width direction outer side Ou.

Claims (3)

A vehicle wheel drive device incorporating an in-wheel motor for driving a wheel and a disc brake for braking the wheel in a rim of the wheel,
In the vehicle wheel drive device, the in-wheel motor includes a cylindrical outer rotor fixed inside the rim, and a cylindrical inner stator disposed inside the outer rotor and connected to the vehicle body side.
The disc brake comprises a hollow disc-like brake disc attached to the outer rotor, and a caliper attached to the inner stator,
The brake disc has a blowing fin for blowing air to the in-wheel motor, a power generating fan that rotates by receiving air blown from the blowing fin, a power generation that is driven by the power generating fan and that can generate electric power. A vehicle wheel drive device comprising: a motor generator having a motor; and a battery for storing electric power generated by the motor generator . The motor generator is configured to drive the power generation fan by being supplied with electric power from the battery when the brake disk rotates at a low speed, and when the power generation fan is driven by at least the motor generator 2. The vehicle wheel drive device according to claim 1, which also serves as an air cooling fan for air cooling the in-wheel motor. A vehicle wheel drive device incorporating an in-wheel motor for driving the wheel and a disc brake for braking the wheel in the rim of the wheel and concentrically with the rim,
In the vehicle wheel drive device, the in-wheel motor includes a cylindrical outer rotor fixed inside the rim, and a cylindrical inner stator disposed inside the outer rotor and connected to the vehicle body side.
The disc brake includes a brake disc attached to the outer rotor and a caliper attached to the inner stator.
The brake disc includes a flange attached to an outer end portion of the outer rotor in the vehicle width direction, a connecting portion extending from the flange to the outer side in the vehicle width direction, and a radially inner portion from the outer end portion of the connecting portion in the vehicle width direction. It consists of a hollow disk-shaped disk part that extends toward the brake and
Further, the brake disk is configured to be capable of generating electric power by being driven by the power generation fan and the function of an electric motor driven by the power generation fan that rotates by receiving air from the air flow fin. And a battery for storing the power generated by the motor generator,
The blowing fin is disposed on the disk part side of the brake disk,
The motor generator is disposed between the flange and the air blowing fin, and is configured to receive the power of the battery and drive the power generation fan during low-speed rotation of the brake disk.
The power generating fan is disposed between the flange and the air blowing fin, and serves also as an air cooling fan that cools the in-wheel motor at least when driven by the motor generator. Vehicle wheel drive device.

Images