GB1364015A - Gas control valve assemblies having an ignition responsive thermo electric safety device - Google Patents

Abstract

1364015 Piezo-electric igniters; rotary control valve assemblies JOH VAILLANT KG 24 Jan 1972 [3 Feb 1971] 3277/72 Headings F4F and F4T [Also in Division F2] A gas-control valve assembly comprises an ignition-responsive thermo-electric safety device including a safety valve 42, Fig. 11; a pilot valve 7; a rotary handle 2 co-operable with said valves and rotatable from a gas-off first position through an ignition stand-by second position to a gas-on third position; a piezo-electric ignition device 27, Fig. 7; and an impact mechanism 23 co-operable with handle 2 and arranged to strike device 27 on a movement of handle 2; said handle 2 being movable axially to a displaced position when in said second position thereby opening safety valve 42 to release an ignition gas flow, the handle being rotatable in the displaced position to operate impact mechanism 23. Pilot valve 7 is opened on rotation of handle 2 to said second position by a stem 8 engaging a cam 6 on a rotary cup 3, Fig. 2, connected to handle 2. A projection 21, Fig. 7, from handle 2, acts on rotation of handle 2, in the depressed state, between said second and third positions to cock an arm 51, carrying a hammer 35, against the action of a spring 24. A cam-follower 13, Fig. 2, on the cup 3 engages a cam-track 16 on a member 14 so that depression of handle 2 acts via member 14, a spindle 15, Fig. 11, lever 88, and a collar 152 on a tappet 39 to open safety valve 42. If ignition occurs, a thermocouple energizes a solenoid 44, of insufficient power to open valve 42 from the closed state, to hold valve 42 open. Depression of handle 2 when in the ignition stand-by second position is permitted, and the handle is retained depressed during rotary movement from said second position through said third position to a full-on fourth position by coaction of projections 20, Fig. 2, with recesses 19 in a flange of cup 3. Axial movement of handle 2 whilst in the fourth rotational position to the undepressed state allows a spring 54 to move tappet 39 to a position allowing a spring 55 to open a main gas valve 40 by means of collars 152, 45 on tappet 39. The interengagement of cam 13, track 16, spindle 15, lever 88 and tappet 39 prevents valve 40 from being opened during the preceding movements of handle 2. A reverse rotatory movement of handle 2 when undepressed results in closure of all of valves 7, 40, 42.