GB453918A - Improvements in or relating to thermostatically controlled valve devices - Google Patents

Abstract

453,918. Thermally-actuated valves. WALKER, C. BELL-, 38, South Bar, Banbury, Oxfordshire, and SMITH & SONS (MOTOR ACCESSORIES), Ltd., S., Cricklewood Works, Cricklewood, London. March 16, 1935, No. 8259. [Class 135] In thermally-actuated valve apparatus comprising a main valve 14 actuated by heatresponsive means which is influenced by fluid in a conduit 32, 30, 31, 33 passing adjacent the said means and byepassing the valve 14, a pilot valve 38 controlling the byepass conduit is operated by pressure-responsive means 42 in accordance with temperature variations at a remote point. The Figure shows a valve suitable for a hot water circulating system. The lift valve 14 is opened against the pressure of a spring 15 by the compression of a bellows 23 due to the expansion of a heat-responsive liquid such as toluene in the space between the bellows and a tubular container 17. The latter has diametrically opposite external flanges 26 and is surrounded by a casing 28 so that two arcuate chambers 30, 31 are formed. These chambers communicate with the valve inlet 11 and the valve outlet 12 respectively through passages 32, 33 formed partly in a heat insulating member 19 having a bleed port 25 and a bush 20 for the valve spindle 21. A piston valve 38 in a boss 34 having arcuate slots 36, 37 controls the flow in the byepass conduit. The pilot valve 38 is closed against the pressure of a spring 48 by the compression of a bellows 42 due to the expansion of a liquid such as toluene in a closed system comprising the space between the bellows 42 and an outer container 44, a conduit 53 of narrow bore, a narrow space 55 of adjustable volume and a tubular coil 62 connected to the space 55 at 64. The space 55 is formed by a diaphragm 58 and a recessed part 56 arranged with the coil 62 in a fitting 54 having a grill 63 and an adjusting knob 59 with a pointer enabling the space 55 to be adjusted for a desired temperature. The fitting 54 is located, at a point remote from the main valve, in the compartment to be heated. The container 44 has a stop flange 52 for the bellows and may have additional thermostatic means to compensate for local temperature changes. In a modification, suitable for steam heating systems, the pilot valve is in the form of a lift valve and the chamber 30, which communicates with the inlet of the system by a separate pipe, is of substantially annular form, whilst the chamber 31 is replaced by an outlet bore in the wall of the container 17. The invention is also applicable to cooling systems. According to the Provisional Specification, heat may be supplied to the heatresponsive means by a combustible gas or liquid the supply of which is controlled in accordance with temperature changes by a pilot valve. Specification 29964/13, [Class 135], is referred to.