GB827538A - Pneumatic pressure regulator - Google Patents

Abstract

827,538. Fluid-pressure servomotor-control systems. DREYER, ROSENKRANZ & DROOP A.G. July 2, 1956 [July 2, 1955], No. 20363/56. Class 135. A process pressure in a chamber 13 between diaphragms 12, 14 is balanced against a set presure in a chamber 15 between diaphragms 14, 16. Variations in the process pressure regulate escape of air through a nozzle 1 from a chamber 2 supplied from a constant pressure source 18 through a restriction 10 to a chamber 11. The resultant change in pressure in chamber 2 moves diaphragms 3, 3 to admit air from 18 past a valve 7 into a chamber 4 or release air from said chamber to atmosphere through a port 9. The change in pressure in chamber 4 reacts in chamber 11 to restore diaphragms 12, 14, 16 and to re-adjust the escape from nozzle 1 to restore diaphragms 3, 3 and valve 7 to their original positions, thus providing a proportional response to the process pressure variation. The pressure from chamber 4 also builds up in a chamber 17 through an adjustable needle valve 21 to provide an integral response pressure on the diaphragms 12, 14, 16. This pressure in chamber 17 acts on another diaphragm 20 which controls a nozzle la to regulate the pressure in a chamber 2a supplied from source 18 through a restriction 10a. This pressure acts through a diaphragm 3a to regulate the supply of pressure to, and exhaust from, a chamber 4a through a valve 7a. The pressure in chamber 4a is in direct proportion to the integral component of the process pressure variation and is transmitted to a line 19 leading to the actuating device of a pressure regulator controlling the process pressure.