GB228652A - Improvements in or relating to thermally controlled valves - Google Patents

Abstract

228,652. Spencer, A. L. H., and Spencer-Bonecourt, Ltd. Nov. 14, 1923. Thermostats.-A thermostatically controlled valve particularly applicable for controlling the supply of gas to gas heaters for steam boilers, steam superheaters, air and water heaters and the like and of the type in which a diaphragm main valve is actuated by fluid pressure under the control of a pilot valve has the diaphragm chamber fitted with an adjustable bye-pass K<0> to permit the passage of sufficient gas to maintain the main burner always alight. The thermostatic device comprises a pair of concentric tubes M, N adjustably connected to the body A of the heater one at each end. At their free ends the tubes are slotted to receive a multiplying lever L adapted to bear against an adjustable abutment H<0> on the spindle of the pilot valve G. The lever L is provided with a knee joint Y normally held in the straight position by an adjustable spring L<2> and passes through a bracket O<1> fitted with a spring stop O. The auxiliary valve is normally held to its seat by a spring H adjusted by a nut H<1>, but when opened by the thermostat it admits inlet pressure to the back of the diaphragm E via ports D<2>, F<1> and pipe G<0>. The diaphragm is then closed by its own weight or elasticity or by a weight or spring load. To enable the valve to open when the pilot valve is closed the cover F is provided with a vent leading to atmosphere or a burner I. To maintain this burner alight in spite of the intermittent working of the apparatus, a bye-pass J controlled by a screwed member J<1> is provided. A fluid o:her than that passing through the valve may be employed for actuating purposes.