GB726845A - Improvements relating to controlling the supply of gas to the burners of water boilers or the like - Google Patents

Abstract

726,845. Controlling gas burners. JACKSON BOILERS. Ltd., and MUSTILL, C. W. March 12, 1953, No. 6788/53. Class 75 (1). [Also in Group XXIX] Gas is supplied to the burner 2 of a water boiler through a main gas valve 5 mechanically connected to the main draw-off tap 3 of the boiler, and through a' diaphragm-operated gas valve 7 placed in parallel with the main gas valve 5. The operation of the diaphragm-operated valve 7 is effected by one or more gas valves 8, 9 each connected in series by a pipe 10 with a chamber on one side of the diaphragm of the valve 7. The valves 8, 9 are arranged in parallel to one another and the pipe 10 has an open end 11 near the b'urner 2. If any of the valves 8, 9 is open, gas flows through the pipe 10 and reduces the pressure on one side of the diaphragm, which moves to open the gas valve 7. The valves 8 are mechanically connected to side draw-off taps of the boiler, and the valve 9 is thermostatically actuated. The valves 5, 7 may be separate units arranged on opposite sides of the boiler, or as in Fig. 4, may be included in a single unit. In this, the main gas valve is a hollow plug 28 with inlet 33 and outlet 34, and an open end. When the hollow plug 28 closes the inlet port 35, a valve 31 carried by a diaphragm 30 controls the gas flow through the open end of the plug to the outlet 36. When the valves 8, 9 are closed, gas leaks through the passage 42 into the chamber 41 until the pressures on both sides of the diaphragm are equalized A spring 40 urges the diaphragm valve 31 towards its closed position, this movement being limited by the slidable engagement of a collar 37a on the diaphragm with an adjustable stud 37. When one of the valves 8, 9 opens, the pressure in the chamber 41 is reduced and the valve 31 opens. In a modification the valve 31 is above the plug 28. and is urged to close by gravity; the spring 40 is omitted.