Temperature responsive hydraulic system and valve means therefor

• Main Author: BORN ELLIS H
• Format: Patent
• Language: English
• Published: 17.09.1968
• Subjects: ACTUATING-FLOATS; BLASTING; COCKS; CONTROLLING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; DEVICES FOR VENTING OR AERATING; ENGINEERING ELEMENTS AND UNITS; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; HYDRAULICS OR PNEUMATICS IN GENERAL; LIGHTING; MECHANICAL ENGINEERING; PHYSICS; REGULATING; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES; TAPS; THERMAL INSULATION IN GENERAL; VALVES; WEAPONS

1,193,718. Cooling hydraulic transmissions. ABEX CORP. 11 Sept., 1967 [13 Sept., 1966], No. 41451/67. Heading F2C. [Also in Divisions F4 and G3] In an hydraulic circuit comprising a motor 79 driven by a pump P, the oil leaving the motor normally returns to sump via line 80, valve 26, 29, line 82 and heat exchanger 83. However, some oil can return via orifice 32 and passages 36, 37, 45 and 46, and when the oil reaches a predetermined temperature, it acts on thermally-responsive element 40 and causes the latter to move valve member 39a further into bore 37b to restrict flow through the latter to build up pressure in chamber 30a to urge valve member 29 towards its seat to restrict flow through line 80. Some oil now flows through 81 to motor 84 to drive a fan 85 adapted to direct cooling air over heat exchanger 83. The quantity of oil by-passed through motor 84 is then controlled to maintain the oil temperature constant.