JP4511976B2 - Vehicle drive device - Google Patents

Description

  The present invention relates to a vehicle drive device, and more particularly to a vehicle drive device including an in-wheel motor.

  Since the conventional in-wheel motor has a large motor unit size, a double wishbone type suspension in which the upper and lower sides are connected by thin arms is employed.

  On the other hand, in order to reduce unsprung weight, an in-wheel motor of a type in which the motor is miniaturized and a reduction gear is provided has been developed. In this type, an oil pump is required for lubrication of the gear of the reduction gear. The power of the oil pump is taken from a rotating shaft synchronized with the wheel shaft having a low rotational speed in order to achieve weight reduction and low loss. As a result, the axial length of the entire motor unit (length in the width direction of the vehicle) becomes long.

  In addition, in the double wishbone type suspension, the shock absorber shaft is directed toward the tire contact surface so that priority is given to ride comfort and the necessary rolling force does not enter, resulting in overlapping with the wheel shaft. If an in-wheel motor with a long shaft length is mounted, the position where the shock absorber is attached to the lower arm must be located on the inner side of the vehicle, and the arm ratio of the shock absorber becomes a small value of 0.5 or less. The arm ratio is expressed as a value obtained by dividing the length from the vehicle body side attachment end serving as a fulcrum of the lower arm to the shock absorber attachment position by the length from the vehicle body side attachment end of the lower arm to the knuckle attachment position.

  If the arm ratio is small, the shock absorber and the coil spring must receive a large force, and the diameter of the shock absorber and the diameter of the coil spring must be increased. This leads to further deterioration of the arm ratio and occupation of valuable wheel house space.

  On the other hand, it is also considered to adopt a strut suspension for an in-wheel motor vehicle.

  Japanese Patent Application Laid-Open No. 2001-315534 (Patent Document 1) discloses a motor mounting structure of an in-wheel motor vehicle in which a strut suspension is employed. A shock absorber is provided between the in-wheel motor and the vehicle body.

Japanese Patent Laid-Open No. 2001-301472 (Patent Document 2) discloses a method for fixing a cable that connects an in-wheel motor and an in-vehicle device.
JP 2001-315534 A JP 2001-301472 A Japanese Patent No. 2769323

  However, the strut type suspension tends to increase in size in the vehicle height direction, and as shown in Japanese Patent Application Laid-Open No. 2001-315534 (Patent Document 1), a shock absorber is stacked on the top of the in-wheel motor. In the structure, there is a problem that it is difficult to adopt in a sports type vehicle or a small vehicle with a low vehicle height.

  Further, in the cable fixing method as disclosed in Japanese Patent Application Laid-Open No. 2001-301472 (Patent Document 2), stress is applied to the connector portion during vibration of the wheel or steering, and the copper wire of the cable may be broken.

  An object of the present invention is to provide a vehicle drive device that is downsized while mounting an in-wheel motor.

  Another object of the present invention is to provide a vehicle drive device in which the occurrence rate of disconnection faults in wiring is reduced.

  In summary, the present invention is a vehicle drive device, in which a rotating electric machine at least partially disposed in a wheel and a side of the rotating electric machine are arranged, and a lower end is arranged below an upper part of the rotating electric machine. And a shock absorber that expands and contracts according to the vertical movement of the wheel, and a connecting portion that connects the rotating electrical machine and the outer cylinder of the shock absorber.

  Preferably, the connecting portion includes an arm portion that is provided at an upper portion of the case of the rotating electrical machine and extends toward a shock absorber located on the side of the case, and a joint portion that connects an outer cylinder of the shock absorber to the arm portion.

  More preferably, the joint portion is provided at least above the lower end of the shock absorber.

Preferably, the rotating electrical machine includes a hollow rotor, and the vehicle drive device further includes a speed reducer that decelerates the rotation of the rotating electrical machine and transmits it to a shaft that penetrates the hollow portion of the rotor, and rotates the wheel by the shaft. The shock absorber, the speed reducer, and the rotating electrical machine are arranged in the order of the shock absorber, the speed reducer, and the rotating electrical machine.

  According to another aspect of the present invention, there is provided a vehicle drive device in which a rotating electric machine at least partially disposed in a wheel, a wiring connecting portion provided in the rotating electric machine, and connecting the wiring connecting portion to the vehicle body side device And a clamp part for fixing the wiring to the rotating electrical machine at an intermediate part from the wiring connection part to the vehicle body side device.

  Preferably, the clamp unit fixes the wiring by aligning the longitudinal direction of the wiring with a direction parallel to the vehicle traveling direction.

  Preferably, the vehicle drive device is disposed on a side of the rotating electrical machine, and a lower end is disposed below the upper part of the rotating electrical machine, and expands and contracts according to the vertical movement of the wheel, and the rotating electrical machine and the shock absorber. It further includes a connecting portion that connects the outer cylinder, and an oil pump that is provided on a side surface of the rotating electrical machine below the lower end of the shock absorber. The clamp portion is provided in a gap between the lower end of the shock absorber and the oil pump.

  According to the present invention, the shock absorber is disposed on the side of the rotating electrical machine so as to partially overlap in the height direction. As a result, the height of the vehicle drive device can be prevented from increasing, and a vehicle drive device employing an in-wheel motor that can be mounted on a sports type vehicle or a small vehicle can be realized.

  Furthermore, since the wiring is fixed to the rotating electrical machine by the wiring clamp, disconnection at the wiring connection portion can be avoided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a perspective view of the vehicle drive apparatus according to the first embodiment.

  Referring to FIG. 1, this vehicle drive device is disposed on a wheel 510, an in-wheel motor 520 disposed in the wheel, and on the vehicle body inner side of the in-wheel motor, and expands and contracts according to the vertical movement of the wheel 510. A shock absorber 560. The shock absorber 560 includes an outer cylinder 564 in which oil, nitrogen gas, or the like is sealed, a piston rod 566 to which a piston that slides inside the outer cylinder is attached at the tip, an absorber cover 568 that covers the piston rod, and not illustrated. And a spring seat 562 on which the spring coil is disposed.

  The in-wheel motor 520 includes a sensor box 534, a terminal box 532 in which connectors of U-phase, V-phase, and W-phase power cables 536, 538, and 540 are arranged, and cables 534, 536, 538, and 540 in-wheel. A wiring clamp 522 that is fixed to the case of the motor 520, a brake caliber 550 that accommodates a brake pad for pressurizing and holding a brake disk, a knuckle spindle 592 to which a lower arm (not shown) is attached, and a ball joint 526 for attaching a tie rod are provided. It is done.

  The tie rod pushes the tie rod mounting ball joint 526 in accordance with the steering angle, whereby the wheel 510 is steered.

  On the rotating shaft of the in-wheel motor 520, an oil pump 524 that sends out oil for lubricating the reduction gear housed in the in-wheel motor 520 is provided. The wiring clamp 522 is housed in a gap portion between the shock absorber 560 and the oil pump 524, thereby reducing the wiring space.

  The wiring clamp 522 fixes the cables 534, 536, 538, and 540 to the in-wheel motor 520 at an intermediate portion from the terminal box 532 to the device on the vehicle body side. As a result, the cables 534, 536, 538, and 540 are supported on both sides with respect to the in-wheel motor 520 between the terminal box 532 and the wiring clamp 522, and the terminal box is used during wheel steering and shock absorber expansion / contraction. The stress applied to the connector at the attachment portion can be relaxed, and the wiring is less likely to be disconnected.

  Further, the wiring clamp 522 fixes the cables 534, 536, 538, and 540 in the vicinity of the lower end of the shock absorber so that the vehicle traveling direction and the longitudinal direction of the cable are aligned in parallel. As a result, the relative vertical displacement between the wheel 510 and the vehicle body due to the stroke of the shock absorber, and the substantially horizontal relative displacement between the wheel 510 and the vehicle body due to the steering are applied to the wiring portion from the wiring clamp 522 to the vehicle body. In addition, since the wire is deformed by acting in the same plane in the substantially vertical direction and the substantially horizontal direction, it is difficult to apply a stress in the twist direction that causes the wire to be twisted. The wiring clamp 522 is sufficient if the wiring is fixed so that the parallelism in the vehicle propulsion direction and the cable longitudinal direction is maintained to the extent that the wiring is not fatigued due to repeated deformation in the wiring.

  An arm to be attached to the shock absorber is provided on the upper portion of the housing of the in-wheel motor 520. This arm is fixed to the outer cylinder 564 of the shock absorber 560 by a clamp band 580, nuts 528 and 530, and a bolt (not shown). .

  FIG. 2 is a front view of the vehicle drive device of the first embodiment.

  Referring to FIG. 2, the wheel 510 is cut away from the front half so that the in-wheel motor 520 can be easily illustrated. The wheel 510 includes a wheel disc 514 and a rim portion 512. A tire (not shown) is attached to the rim portion 512.

  An upper end portion of the piston rod 566 is fixed to the vehicle body 800. The knuckle spindle 592 is fixed to the lower arm 590 with bolts and nuts. A space between the vehicle body and the shock absorber 560 can be used as a wiring space in which a sensor cable and a power cable are provided.

  As can be seen in FIG. 2, the case of the in-wheel motor 520 is integrated with a knuckle that rotatably supports the wheel hub.

  FIG. 3 is a schematic cross-sectional view for explaining the structure of the in-wheel motor 520.

  Referring to FIG. 3, in-wheel motor 520 is attached to motor housing 544, gear case 545 attached to motor housing 544 with bolts 548, gear case lid 546 covering the gear case from the vehicle body side, and attached to motor housing 544 with bolts 549. Motor housing lid 547.

  A ball joint 594 is attached to the motor housing 544 so that the motor housing 544 is fixed to the knuckle spindle 592 in a state in which the angle can be changed with vertical movement.

  The wheel disc 514 is fixed to the wheel hub 620 by bolts 601. A brake rotor 552 is attached to the wheel hub 620. The wheel hub 620 is rotatably supported with respect to the motor case integrated with the knuckle by providing ball bearings 611 and 612 between the wheel hub 620 and the motor housing lid 547.

  In-wheel motor 520 includes a stator core 671 housed in motor housing 544, a stator coil 672 wound around stator core 671, and a rotor 673 housed inside stator core 671. A permanent magnet is embedded in the rotor 673.

  The in-wheel motor 520 further includes a sun gear 682, a ring gear 685, a planetary carrier 684, a pinion gear 683, and a pin 686 that is a rotation shaft of the pinion gear 683 housed in the gear case 545. A needle bearing is provided in the gap between the pinion gear 683 and the pin 686.

  The shaft of the sun gear 682 rotates with the rotation of the rotor 673. The shaft of the sun gear 682 is rotatably supported between the motor housing lid 547 and a ball bearing 614. Planetary carrier 684 is supported by ball bearing 617 so as to be rotatable with respect to gear case lid 546.

  Similarly, the planetary carrier 684 is supported by a ball bearing 616 so as to be rotatable with respect to the axis of the sun gear 682, and is also supported by the ball bearing 615 so as to be rotatable with respect to the gear case 545.

  The sun gear 682 is hollow, and a shaft 710 that is spline-fitted to the wheel hub 620 and the planetary carrier 684 is disposed therein. An oil passage 711 is provided on the gear case side of the shaft 710.

  The rotor 673 included in the in-wheel motor 520 is hollow, and the speed reducer transmits the reduced speed to the shaft 710 penetrating the hollow portion of the rotor 673 by reducing the rotation of the in-wheel motor 520. The wheel hub 620 and the wheel 510 are rotated by the shaft 710.

  The operation of the speed reducer will be described in some detail. When the rotor 673 rotates, the sun gear 682 rotates accordingly. Ring gear 685 is fixed to gear case 545. The pinion gear 683 meshes with both the sun gear 682 and the ring gear 685. When the sun gear 682 rotates, the pinion gear 683 rotates accordingly. Since the ring gear 685 is fixed to the gear case 545, the ring gear does not rotate. Therefore, the rotation of the sun gear 682 is decelerated and the planetary carrier 684 is rotated. The planetary carrier 684 is spline-fitted with the shaft 710, and this rotation rotates the wheel hub 620 via the shaft 710 and the wheel 510 rotates.

  An oil pump 524 that sucks up the lubricating oil accumulated in the lower part of the gear case from the oil passage 721 and sends it to the oil passage 711 is attached to the gear case lid 546 in order to lubricate the speed reducer portion. Since the oil pump 524 is preferably rotated by the shaft 710 rotated with a large torque after deceleration, the oil pump 524 is provided so as to protrude toward the vehicle body on the shaft 710.

  FIG. 4 is a conceptual diagram for explaining an arrangement relationship of elements of the vehicle drive device of the first embodiment.

  Referring to FIG. 4, at least a part of in-wheel motor 520 is disposed in a wheel (not shown).

  The shock absorber 560 is disposed on the side of the in-wheel motor 520 and its lower end is disposed below the upper end of the motor housing 544 of the in-wheel motor 520 by a height D. An arm portion 542 is provided on the upper portion of the motor housing 544, and the arm portion 542 extends toward a shock absorber 560 positioned on the side of the motor housing 544.

  The clamp band 580 fixes the outer cylinder 564 of the shock absorber 560 to the arm portion 542 with bolts and nuts. The position where the clamp band 580 is provided is at least a height D higher than the lower end of the shock absorber 560.

  An upper end portion of the piston rod 566 is fixed to a strut mount 569 of the vehicle body 800. When the wheel vibrates up and down, the shock absorber 560 expands and contracts in the vertical direction, and the vertical movement is absorbed by the sliding of the piston 567 and the repulsion of the spring 563.

  As described above, in the first embodiment of the present invention, the shock absorber 560 is arranged on the side of the motor housing 544 so as to partially overlap in the height direction. As a result, the height of the vehicle drive device can be prevented from increasing, and a vehicle drive device employing an in-wheel motor that can be mounted on a sports type vehicle or a small vehicle can be realized.

  In addition, since the arm ratio can be increased by adopting the strut type suspension, the arm ratio can be increased, and the diameters of the spring and the shock absorber can be kept small. In addition, kingpin offset, caster angle, and trail can provide the same performance values as ordinary vehicles. Furthermore, the structure is easy to design because a large wiring space can be secured between the in-wheel motor and the body even when the steering wheel turns or moves up and down.

  Further, since the wiring is fixed to the motor by the wiring clamp, disconnection at the connector portion of the connection box can be avoided. Further, since the wiring clamp is housed in the gap portion between the shock absorber and the oil pump, it is possible to avoid projecting only the wiring portion when fixing the wiring to the in-wheel motor. Furthermore, since the direction of fixing with the wiring clamp coincides with the horizontal direction of the cable, the cable is only subjected to bending stress even when the handle is cut, and the reliability is improved.

[Embodiment 2]
FIG. 5 is a front view showing the configuration of the vehicle drive apparatus of the second embodiment.

  Referring to FIG. 5, the vehicle drive device of the second embodiment is different from the vehicle drive device described in FIG. 2 in that an oil cooler 900 is provided on the vehicle body side of the oil pump.

  Since the in-wheel motor is arranged in the wheel, it is difficult for the traveling wind to hit, and the temperature rises unless cooling is performed effectively. However, if a hose that circulates lubricating oil or cooling water between the radiator and the radiator disposed on the body side is provided, the reliability of the hose is required. Therefore, it is desirable to effectively perform cooling near the in-wheel motor.

  As shown in FIG. 1, fins for cooling are provided on the surface of the in-wheel motor 520. Generally, the housing, gear case, and lid of the in-wheel motor are made of aluminum casting, so the thickness of the fin is It is difficult to make it 5 mm or less, and it is difficult to make the protruding portion of the fin 10 mm or more.

  As shown in FIG. 5, in the second embodiment, a strut-type suspension is employed, so that a larger space is secured on the body side of the in-wheel motor than the double wishbone suspension that has been conventionally employed. Can do. Accordingly, the oil cooler 900 is arranged in this space to effectively dissipate heat.

  A flow path through which the lubricating oil flows is formed inside the oil cooler 900. After the lubricating oil is guided from the oil pump 524 to the oil cooler 900 and cooled, the lubricating oil is supplied to the gear of the internal reduction gear portion. The

  For example, the oil cooler 900 may be made of copper or the like. Further, since the strength as high as that of the motor housing integrated with the knuckle is not required, a structure like a radiator can be adopted for the oil cooler 900. Further, if the oil cooler 900 is made of copper and the fins are made thin and large, it is more advantageous for heat dissipation.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. 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 is a perspective view of a vehicle drive device according to a first embodiment. 1 is a front view of a vehicle drive device according to a first embodiment. It is a schematic sectional drawing for demonstrating the structure of the in-wheel motor 520. FIG. FIG. 3 is a conceptual diagram for explaining an arrangement relationship of elements of the vehicle drive device of the first embodiment. FIG. 5 is a front view showing a configuration of a vehicle drive device according to a second embodiment.

Explanation of symbols

  510 wheel, 512 rim, 514 wheel disc, 520 in-wheel motor, 522 wiring clamp, 524 oil pump, 526 ball joint, 528, 530 nut, 532 terminal box, 534 sensor cable, 536, 538, 540 power cable, 542 Arm part, 544 Motor housing, 545 Gear case, 546 Gear case cover, 547 Motor housing cover, 548, 549, 601 Bolt, 550 Brake caliber, 552 Brake rotor, 560 Shock absorber, 562 Spring seat, 563 Spring, 564 Outer cylinder, 566 Piston rod, 567 Piston, 568 Absorber cover, 569 Strut mount, 580 Clamp band, 590 Lower Arm, 592 knuckle spindle, 594 ball joint, 611, 612, 614, 615, 616, 617 ball bearing, 620 wheel hub, 671 stator core, 672 stator coil, 673 rotor, 682 sun gear, 683 pinion gear, 684 planetary carrier, 685 ring gear , 686 pin, 710 shaft, 711, 721 oil passage, 800 car body, 900 oil cooler.

Claims (5)

A rotating electric machine at least partially disposed in the wheel;
A wiring connection provided in the rotating electrical machine;
Wiring for connecting the wiring connection part to the vehicle body side device;
A clamp portion for fixing the wiring to the rotating electrical machine at an intermediate portion from the wiring connection portion to the vehicle body side device ;
A shock absorber disposed on the side of the rotating electrical machine and having a lower end disposed below the upper part of the rotating electrical machine and extending and contracting in accordance with the vertical movement of the wheel;
A connecting portion for connecting the rotating electrical machine and the outer cylinder of the shock absorber;
An oil pump provided below the lower end of the shock absorber on the side surface of the rotating electrical machine ,
The said clamp part is a vehicle drive device provided in the clearance gap between the lower end of the said shock absorber, and the said oil pump .   The vehicle drive device according to claim 1, wherein the clamp unit fixes the wiring by aligning a longitudinal direction of the wiring with a direction parallel to a vehicle traveling direction. Fixed to said vehicle body of the electric rotating machine, further comprising an oil cooler for cooling the lubricating oil of the rotating electrical machine, a vehicle drive device according to claim 1 or 2. The connecting portion is
An arm portion provided at an upper portion of the case of the rotating electrical machine and extending toward the shock absorber located on the side of the case;
A joint portion connecting the outer cylinder of the shock absorber to the arm portion,
The vehicle drive apparatus according to claim 1 , wherein the joint portion is provided at least above a lower end of the shock absorber. The rotating electric machine is
Including a hollow rotor,
The vehicle drive device comprises:
A shaft for passing through the hollow portion of the rotor and rotating the wheel;
A speed reducer that is disposed on a side of the rotating electrical machine on the vehicle body side and decelerates the rotation of the rotating electrical machine and transmits it to the shaft;
The vehicle drive device according to claim 4 , wherein the shock absorber, the speed reducer, and the rotating electrical machine are arranged in the order of the shock absorber, the speed reducer, and the rotating electrical machine from a vehicle body toward the wheel.

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