Electric motor vehicle drive system having differential gear device whose splined output elements are abuttable on stop member to receive thrust forces applied to vehicle wheel drive members

A drive system for an electric motor vehicle, having (a) a housing structure mounted on a chassis of the vehicle, (b) an electric motor disposed in said housing structure and having a hollow output shaft whose axis is parallel to a transverse direction of the vehicle, (c) a first and a second drive member which are supported by said housing structure, rotatably about respective axes coaxial with said output shaft, said drive members being operatively connected to a first and a second drive wheel, respectively, (d) an intermediate shaft disposed coaxially with said output shaft so as to extend through a center bore of said output shaft, and connected at one axial end thereof to said second drive member for rotation therewith, (e) a differential gear device of planetary gear type disposed in said housing structure coaxially and in series with said output shaft, said differential gear device including a sun gear, a ring gear, a carrier and a planetary gear, one of which serves as an input element that receives power transmitted from said electric motor, and the others of which include two output elements through which the power received by said input member are distributed to said first drive member and said intermediate shaft, and (f) a plurality of thrust bearings for positioning the elements of said differential gear device so as to inhibit movements of said elements in an axial direction of said output shaft, wherein the improvement comprises:

• said first drive member including a first end portion having a splined outer circumferential surface remote from said first drive wheel;
• said intermediate shaft including a second end portion having a splined outer circumferential surface remote from said second drive member;
• said two output elements of said differential gear device having a first center bore and a second center bore, respectively, said first and second center bores being defined by respective splined inner surfaces which engage said splined outer circumferential surfaces of said first and second end portions, respectively;
• and
• a stop member provided on one of said two output elements, so as to protrude into at least one of said first and second center bores, such that opposed end faces of said first and second end portions are abuttable on opposite ends of said stop member, whereby a transverse thrust force applied to said first and second drive members in transversely inward direction of the vehicle is received by said stop member.