Hydrostatic vehicle transmission system - has working circuit pressure and temp. switches releasing pressure from control circuit

摘要

The system incorporates variable-capacity primary and/or secondary portions whose hydraulic adjusting rams are automatically returned to the starting position on cessation of pressure and are connected to a control circuit supplied by a constant-vol. pump and also connected via a control unit to the return pipe to vary the control pressure. The hydraulic working circuit is protected against overload by two pressure relief valves working in opposite directions and parallel to the hydraulic motor. In the working circuits of the system are one or more pressure amd temp. switches, whose contacts are in series with an electrical actuator releasing the pressure from the control circuit. The actuator can be in the form of a pressure relief valve in series with an electrically operated slide valve between the control circuit and the return pipe.