Patent ID: 8870708

Claim:
A direct-type driving module of a differential gear for an electric vehicle, comprising: a driving bevel gear connected to enable power transmission with respect to a differential gear of a differential device, the driving bevel gear including a shaft coupling part having splines formed on an outer circumferential surface of the shaft coupling part; a coupler having a first connection part provided at a first side and a second connection part provided at a second side opposite the first side, the first connection part having a first fastening groove that is inwardly recessed along a length wise direction of the coupler and has splines formed on an inner circumferential surface of the first fastening groove so as to be spline-coupled to a driving axel of a driving motor, and the second connection part having a second fastening groove that is inwardly recessed along the length wise direction of the coupler and has splines formed on an inner circumferential surface of the second fastening groove so as to be spline-coupled to the shaft coupling part of the driving bevel gear, wherein the splines of the first fastening groove and the second fastening groove have recesses and protrusions alternately arranged along a circumferential direction of the first fastening groove and the second fastening groove and stretched along the length wise direction of the coupler; a first bearing installed at the coupler and having an inner wheel supported to the coupler and an outer wheel supported to a housing of the differential device; a second bearing installed at the driving bevel gear and having an inner wheel supported to the driving bevel gear and an outer wheel supported to a housing of the differential device; and a fastening part connecting the coupler and the driving bevel gear to each other, wherein the first and second bearings are supported to one and the other surfaces of the housing to be mounted at opposite sides facing each other, the coupler includes a supporting part that has a larger diameter than the second connection part and is disposed between the first connection part and the second connection part so as to support the first bearing installed on an outer circumferential surface of the second connection part, and the spline-connection between the first fastening groove of the first connection part of the coupler and the driving axel of a driving motor is not restrained with respect to the lengthwise direction of the driving axel so that the driving axel may slide with respect to its lengthwise direction.