GB934072A - Improvements in a valve device for the conduit supplying the combustible gas to a gas burner - Google Patents

Abstract

934,072. Valves. EL- & GASSVETSNING A.B. April 21, 1961 [May 13, 1960], No. 14495/61. Class 135. A safety valve e.g. controlling the supply of acetylene gas to a burner, has a seat 6 in the inlet 4 with which co-operates a tubular closuremember 7 supported on a spring-loaded diaphragm 8 forming inlet and outlet chambers 3a, 9, respectively. In the flow path between the chamber 9 and valve outlet 2 is an auxiliary closure member 17 having an " O "-ring 18 for sealing the bore 19 leading to the outlet 2, the member 17 being carried by a sleeve 16 in the bore of an insert 13. The sleeve 16 embodies a pair of opposed slots 20 with which coact a pin 21 carried by the insert 13, each slot incorporating a recess 22 and a cam edge; compressed between the pin 21 and the bottom of the sleeve 16 is a spring 25 which urges the member 17 towards the closed position and against the action of which spring the sleeve 16 can be latched with the member 17 in the open position by causing recesses 22 to engage the pin 21. A flame guard 27 and a metal sleeve 28 are mounted in the chamber 9. Both closure members are normally unseated but upon a pressure rise occurring in or beyond the outlet 2, e.g. due to an explosure caused by oxygen in the acetylene gas supply conduit, the pressure rise in chamber 9 seats the member 7 and displaces the sleeve 16 against its spring 25 away from the outlet 2 so causing its rotation due to the pin 21 riding over the cam edges whereby the pin 21 is aligned with the slots 20 so that upon the pressure in the outlet 2 falling the spring 25 seats the member 17. The latter is reopened by rotating the sleeve 16 with a screw-driver passed through the outlet 2.