Hydrostatic vehicle driving system applicable to a working vehicle

A hydrostatic vehicle driving system applicable to a working vehicle, comprising:

• an engine;
• a variable displacement hydraulic pump driven by said engine;
• a hydraulic motor;
• a first hydraulic circuit for driving said hydraulic motor interposed between said hydraulic pump and said hydraulic motor;
• an axle driven by said hydraulic motor;
• a manual speed control member provided on said working vehicle for changing capacity of said hydraulic pump;
• a hydraulic actuator for changing capacity of said hydraulic pump, said hydraulic actuator being controlled according to output of said engine, and
• selection means selecting one of said manual speed control member and said hydraulic actuator so as to change the capacity of said hydraulic pump.

A hydrostatic vehicle driving system applicable to a working vehicle, comprising:

• an engine;
• a variable displacement hydraulic pump driven by said engine;
• a hydraulic motor;
• a first hydraulic circuit for driving said hydraulic motor interposed between said hydraulic pump and said hydraulic motor;
• an axle driven by said hydraulic motor;
• a manual speed control member provided on said working vehicle for changing capacity of said hydraulic pump;
• an actuator for changing capacity of said hydraulic pump, said actuator being controlled according to output of said engine;
• selection means selecting one of said manual speed control member and said actuator so as to change the capacity of said hydraulic pump;
• a charge pump driven by said engine for supplying said first hydraulic circuit with fluid;
• a second hydraulic circuit extended from a discharge port of said charge pump;
• an orifice provided on the way of said second hydraulic circuit,
• wherein said actuator is driven according to difference of hydraulic pressure in said second hydraulic circuit between upstream and downstream of said orifice.

A hydrostatic vehicle driving system applicable to a working vehicle, comprising:

• an engine;
• a variable displacement hydraulic pump driven by said engine;
• a variable displacement hydraulic motor;
• a first hydraulic circuit for driving said hydraulic motor interposed between said hydraulic pump and said hydraulic motor;
• an axle driven by said hydraulic motor;
• a manual speed control member provided on said working vehicle for changing capacity of said hydraulic pump;
• a hydraulic actuator for changing capacity of said hydraulic pump, said hydraulic actuator being controlled according to output of said engine;
• selection means selecting one of said manual speed control member and said hydraulic actuator so as to change the capacity of said hydraulic pump;
• wherein, while said selection means selects said speed control member, capacity of said hydraulic motor is fixed, and
• wherein, while said selection means selects said hydraulic actuator, capacity of said hydraulic motor can be changed.