GB517012A - Improvements in and relating to thermostatically controlled valves - Google Patents

Abstract

517,012. Fluid-actuated valves. SAUNDERS, P. K., and SAUNDERS VALVE CO., Ltd. July 14, 1938, Nos. 22614/39, 22450/38, 25127/38 and 459/39. Divided out of 516,499. [Class 135] [Also in Group XIII] A valve for controlling the cooling-system of an internal combustion engine is operated by fluid pressure generated by the engine and controlled thermostatically by a pilot-valve operated by a bi-metallic element. The thermostatic control is independent of atmospheric pressure, and thus renders unnecessary means for compensating for changes in atmospheric pressure. The valve shown in the Figure is arranged in the radiator by-pass and comprises a casing 1 containing a fixed chamber 6 in which is mounted, by means of packing rings 12, 13, a valve-member 11 consisting of a movable cylinder 11 having a conical end 9 for engaging a seat 10 on the casing. A rotary pilot-valve 18 is mounted on a pin 31 in the cylinder and is formed with radial slots 19 which can register with radial slots 19 in the conical end 9. The pilot-valve is operated by a bi-metallic element consisting a coiled aluminium tube 20 containing a steel wire 21. The tube is secured by clamps 22 to the valve-member 11, and the wire is connected at one end to the pilotvalve and is provided at the other end with a nut 38 abutting on the axially arranged end of the tube. The space between the chamber 6 and casing 1 constitutes a Venturi-passage and communicates through ports 30, and a leak-hole 40 adjustable by a screw 39 with the space between the packing-rings 12, 13, and behind the packing ring 13 respectively. Ports 16, 43, 17 permit a small flow of liquid through the valve-member 11. Normally, the ports 19 are open, the valvemember 11 is closed, and liquid circulates through the radiator. When the temperature of the liquid falls below a pre-determined level, the element 20, 21 rotates the pilot-valve, the ports 19 are closed, the valve-member 11 is opened by the pressure of the liquid, and the radiator is bypassed. The temperatures at which the valvemember 11 is opened and closed are determined by adjustment of the screw 39, and a nut 33 in connection with a returning-spring 32 for the valve-member 18. The valve may be fitted in the main duct of the radiator and arranged to open when the temperature rises. The above-described valve may be replaced by a piston-operated valve and an associated pilot-valve operated by a bi-metallic element.