Coupling structure of in-wheel motor drive device and strut type suspension device
A strut type suspension device has a retractable strut ( 111 ) that connects to an upper portion of an in-wheel motor drive device ( 10 ) so as not to relatively move; and a swingable lower arm ( 116 ) that is coupled to a lower portion of the in-wheel motor drive device in any direction, and permits vertical swinging of the in-wheel motor drive device and also permits steering of the in-wheel motor drive device about a steering shaft (S) that passes through a coupling point ( 119 ) between the lower arm ( 116 ) and the in-wheel motor drive device. An axis (M) of the motor portion ( 21 ) of the in-wheel motor drive device is arranged above a height of the coupling point ( 119 ) of the lower arm ( 116 ).
1. A coupling structure of an in-wheel motor drive device and a strut type suspension device, comprising:
an in-wheel motor drive device having a wheel-hub bearing portion rotatable supporting a wheel hub, a motor portion that is provided offset from an axis of the wheel-hub bearing portion and drives the wheel hub, and a speed reduction portion that reduces a rotational speed of the motor portion to transmit the reduced rotational speed to the wheel hub; and
a strut type suspension device having a retractable strut that connects to the in-wheel motor drive device and a swingable lower arm that is coupled to the in-wheel motor drive device in any direction, permitting vertical swinging of the in-wheel motor drive device and also permitting steering of the in-wheel motor drive device about a steering shaft that passes through a coupling point between the lower arm and the in-wheel motor drive device,
wherein an axis of the motor portion is arranged above the coupling point of the lower arm,
wherein the axis of the motor portion is arranged on a vehicle front side from a vehicle longitudinal position of the axis of the wheel-hub bearing portion, and
wherein the speed reduction portion is a parallel three-shaft type speed reducer having an input shaft that extends along the axis of the motor portion; an output shaft that extends along the axis of the wheel-hub bearing portion; and an intermediate shaft that extends in parallel to the input shaft and the output shaft, and the intermediate shaft is arranged on a vehicle front side from the strut.
2. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein the motor portion is arranged on a vehicle front side from the strut.
3. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein the motor portion and/or the speed reduction portion is/are arranged in a circle having a diameter equal to a rim inner diameter of an in-wheel that connects to the wheel hub.
4. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein an outer peripheral surface of the motor portion is arranged in a position overlapped with the strut with respect to an axial position of the wheel-hub bearing portion.
5. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein a coupling portion of a steering tie-rod of a steering device and the in-wheel motor drive device is arranged in a region on the vehicle rear and/or lower side from the axis of the wheel-hub bearing portion, of an inner-diameter side space defined by the rim inner diameter of the in-wheel that connects to the wheel hub.
6. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein the speed reduction portion includes a plurality of gears, and all the gears are arranged in a position overlapped with the wheel hub with respect to an axial position of the wheel-hub bearing portion.
7. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 1 , wherein the entire motor portion is arranged offset from the axis of the wheel-hub bearing portion.
8. A coupling structure of an in-wheel motor drive device and a strut type suspension device, comprising:
an in-wheel motor drive device having a wheel-hub bearing position rotatably supporting a wheel hub, a motor portion that is provided offset from an axis of the wheel-hub bearing portion and drives the wheel hub, and a speed reduction portion that reduces a rotational speed of the motor portion to transmit the reduced rotational speed to the wheel hub; and
a strut type suspension device having a retractable strut that connects to the in-wheel motor drive device and a swingable lower arm that is coupled to the in-wheel motor drive device in any direction, permitting vertical swinging of the in-wheel motor drive device and also permitting steering of the in-wheel motor drive device about a steering shaft that passes through a coupling point between the lower arm and the in-wheel motor drive device,
wherein an axis of the motor portion is arranged above the coupling point of the lower arm, and
wherein the in-wheel motor drive device further comprises a carrier of which a central portion connects to a non-rotating member of the wheel-hub bearing portion, an upper end portion connects to the strut, and a lower end portion is coupled to the lower arm in any direction.
9. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein the carrier comprises a coupling portion for coupling to a steering device.
10. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein the motor portion and/or the speed reduction portion is/are arranged in a circle having a diameter equal to a rim inner diameter of an in-wheel that connects to the wheel hub.
11. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein an outer peripheral surface of the motor portion is arranged in a position overlapped with the strut with respect to an axial position of the wheel-hub bearing portion.
12. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein a coupling portion of a steering tie-rod of a steering device and the in-wheel motor drive device is arranged in a region on the vehicle rear and/or lower side from the axis of the wheel-hub bearing portion, of an inner-diameter side space defined by the rim inner diameter of the in-wheel that connects to the wheel hub.
13. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein the speed reduction portion includes a plurality of gears, and all the gears are arranged in a position overlapped with the wheel hub with respect to an axial position of the wheel-hub bearing portion.
14. The coupling structure of the in-wheel motor drive device and the strut type suspension device according to claim 8 , wherein the entire motor portion is arranged offset from the axis of the wheels-hub bearing portion.