Patent ID: 6681570
Filing Date: 2004-01-27
Classification: F16D,F16H

Abstract:
A hydrostatic transmission, comprising:a housing formed with a fluid sump; a center section disposed within said fluid sump; a hydraulic pump mounted on said center section; a hydraulic motor mounted on said center section; a fluid passage formed in said center section for hydraulically connecting said hydraulic pump with said hydraulic motor; a bore opening at an outer surface of said center section in communication with said fluid passage; an output operation device for controlling discharged fluid of said hydraulic pump, wherein said output operation device is moved to an operational position from a neutral position; a piston reciprocally inserted into said bore so as to be allowed to project outward from said center section, said piston having an outer surface; a valve disposed within said bore for opening and closing said bore to and from said fluid passage, said valve being biased to be closed by a spring disposed between said valve and said piston; and a member interlocking with said output operation device so as to contact with said outer surface of said piston, wherein, when said output operation device is adjacent to said neutral position and pressure fluid in said fluid passage forcedly opens said valve and flows into said bore, said member drains said pressure fluid in said bore to a low-pressured area.