Patent attributes
There is provided a hydrostatic transmission (HST) in which a hydraulic pump unit operatively driven by a driving power source and a hydraulic motor unit arranged spaced apart from the hydraulic pump unit and operatively driving a driving-wheel are fluidly connected by way of operation fluid lines so as to form a closed circuit. The hydraulic motor unit is provided with motor-side operation fluid passages forming one part of the operation fluid lines. A motor-side charge fluid passage having a first end opened to an outside to form a motor-side charge port and a second end fluidly connected to at least one of the motor-side operation fluid passages is also included. A check valve is interposed in the motor-side charge fluid passage so as to allow the fluid to flow from the motor-side charge port to one motor-side operation fluid passage while preventing reverse flow.