Kuehlvorrichtung zur selbsttaetigen Temperaturregelung des Mediums einer hydraulischen Anlage

965, 951. Fluid-pressure servomotor systems. RICHIER S.A. April 24, 1962 [April 21, 1961], No. 15606/62. Heading G3P. A fluid-pressure servomotor system for automatically controlling the temperature of the fluid in a hydraulic circuit comprises a member 1 responsive to the temperature of the fluid in the circuit, a fan 10 acting as a cooler in a part of the circuit, a hydraulic motor 9 driving the fan and a pump 4 feeding the hydraulic motor, the supply of pressure fluid from the pump to the hydraulic motor being controlled by a conduit which embodies a by-pass between the inlet and outlet of the pump and in which a control valve 3 is regulated by a pilot line 7 communicating with a point without pressure in the hydraulic circuit through the intermediary of a pilot valve 6 operated by the member 1. The pilot valve 6 causes the spring loaded bypass valve 3 to take up a position dependent on the flow through a port 22 on the valve member 15. The extent to which the pump output is by-passed through a passage 23 of the valve 3 determines the speed of the motor 9. In the event of overload, a relief valve 13 opens.