Patent ID: 7849689

Claim:
A hydrostatic transmission unit for a vehicle, comprising: a hydraulic pump comprising an input shaft; a pump casing having a front outer surface, wherein the hydraulic pump is disposed in the pump casing; a hydraulic motor fluidly connected to the hydraulic pump; a gear casing having a first surface and a second surface, wherein the first surface of the gear casing is detachably fixed to the front outer surface of the pump casing and the input shaft extends from the second surface of the gear casing; a first gear disposed in the gear casing and drivingly fixed on the input shaft; a second gear disposed in the gear casing and drivingly meshed to the first gear; and an auxiliary pump unit detachably fixed on the gear casing, wherein the first gear and the second gear transmit a rotary force of the input shaft to the auxiliary pump unit.