GB823645A - Improvements in and relating to apparatus for permitting consumption of gas for a preetermined time whenever required - Google Patents

Abstract

823,645. Valves. RADIATION Ltd. Sept. 12, 1957, No. 28792/57. Class 135. Apparatus for permitting consumption of gas for a predetermined period comprises a normally closed gas supply valve, manually operable means for opening the valve and for putting into operation a timing device set to effect automatic closure of the valve, the timing device comprising means effecting intermittent rotation of a disc or the like carrying one or more operative pins adapted to co-operate with a member after the passage of a predetermined quantity of gas from the timing device, so as to effect closure of the valve. In the apparatus shown operation of a press button i causes a slide bar h to move to the right, allowing its left-hand end to be lifted by a spring 14 and held against a casing 21 by which movement a pin g rotates a lever f clockwise to open the gas supply valve b. Gas passes from an inlet j to an outlet m in communication with a heater, some of it passing through an orifice n at the end of a tube o into a chamber c closed by a loaded diaphragm r. The latter rises and at the end of its travel operates a flap valve p to close orifice n, and the gas in chamber c then escapes through a small orifice 17 so that diaphragm r descends, opening valve p at the end of its travel, and also, through links 13, t, u, v, rotating a ratchet wheel d through one tooth. The cycle is repeated a predetermined number of times, when a pin 5 on wheel d engages slide bar h, forcing it downwardly against spring 14 and allowing it to move to the left to its normal position, a spring 23 turning lever f anticlockwise to close supply valve b. The supply period may be varied by varying the number of detent pins 5 mounted on wheel d.