US Patent 7377331 Damping driving axle

A damping drive axle includes an output shaft divided into a first portion and a second portion, a mounting seat having a centrally defined hole, a first compartment to correspond to and receive therein the first portion of the output shaft and a second compartment to receive therein the second portion of the output shaft, a hollow cylinder with having a triangle opening to allow an extension of the second portion of the output shaft, multiple columns rotatably received in a side defining the triangle opening to selectively lock/release the second portion of the output shaft, multiple cutouts defined in a bottom face of the cylinder and multiple legs extending out from the bottom face of the cylinder, each leg being sandwiched by two adjacent cutouts and an input device to rotate the sleeve of the hollow cylinder.