GB1151597A - Improvements in and relating to Fluid Flow Control Valves - Google Patents

Abstract

1,151,597. Valves. HONEYWELL Inc. 20 June, 1966 [30 June, 1965], No. 27536/66. Heading F2V. Manually operable combustion gas rotary valve comprising a main gas control valve in series with a safety latching valve, and a manual operator which is disconnected from the main valve when the main valve is in the "off" position and the safety valve is open. The valve comprises a housing 10, Fig. 1, having an inlet 12, an outlet 13 and a pilot passage 25; a rotary plug or disc valve 16 having an inlet 22, an outlet 23 and an arcuate pilot passage (24, Fig. 2, not shown); a latching safety valve 15 connected to a stem 37 which is axially displaceable but non-rotatable with respect to the plug valve 16 and which is formed at one end with an armature 28 for co-operation with an electromagnet 31 coupled to a thermostat or bi-metallic strip 32, and at the other end with a transverse pin 50 which is engaged within a T-shaped slot 51 in an operator knob 44 provided with a programming slot 53 into which a fixed programming guide 52 extends. To operate the valve the knob 44 is first depressed with respect to the stem 37 so that the pin 50 moves to the top of the vertical slot 51b and the turned-over end 52a of the fixed programming guide is aligned with the horizontal portion 53a, Fig. 6, of the programming slot. The knob is then turned clockwise whereby the plug valve is brought to the "pilot" position as the end 52a of the fixed programming device reaches the portion 53c of the programming slot. The knob is again depressed and this time displaces the safety valve 15 to the open position where it is maintained by continued pressure on the knob until the electromagnet is energized, in response to a flame set up at the pilot burner following opening of the safety valve, to hold the valve open. The knob is then released and is moved upwardly by a spring whereby the pin 50 is brought into the bottom portion of the slot 51b as the end of the fixed programming guide is aligned with the portion 53a of its slot. The knob can now be rotated to bring the plug valve to the "on" position. If the knob should be rotated to the "off" or "pilot" position from the "on" position and then rotated towards the "on" position again before the safety valve has been released by the electromagnet, depression of the knob 44 merely aligns the pin 50 with the portion 51a of the programming slot and prevents rotation of the plug valve with rotation of the knob. When the plug valve reaches the "on" position it may be arranged to close a pair of contacts for automatic operation of a remote valve associated therewith.