Rear wheel suspension system in vehicle

摘要

In a rear wheel suspension system (30) in a four-wheeled vehicle (10) wherein a joint member (31) is mounted in a rear portion of a vehicle body (11) with a pair of left and right front wheels (13,14) secured thereto, the joint member (31) comprising a roll shaft (41) extending substantially in the longitudinal direction of the vehicle body and a vertical swing shaft (36) extending in the transverse direction of the vehicle body, and a power unit (32) which supports rear wheels (26) and (27) is connected to a rear portion of the joint member (31), thereby allowing the power unit (32) to be secured to the vehicle body (11) rollably and swingably, the roll shaft (41) is mounted so that a front end portion (41a) thereof is positioned lower than a rear end portion (41b) thereof. It is possible to easily attain the reduction in weight of the vehicle, set a weight distribution of the vehicle freely, and improve the vehicular design freedom. Besides, such rear wheel steering rods and rod connecting members as in the prior art are not needed and therefore it is possible to decrease the number of components used in the rear wheel suspension system.