GB269616A - Improvements in or relating to fluid control valves - Google Patents

Abstract

269,616. Stephenson, A., Woodhead, H. E., and Allen-Liversidge, Ltd. Dec. 21, 1925. Blowpipe burners; burners, mounting. - In devices for controlling the passage of gases to blowpipe and like apparatus a wedge member operating a pair of opposed valves mounted upon a common base, is carried by a pivoted operating element mounted to swing between the valve mechanisms, preferably with play to allow for slight lateral movement to equalize the pressure on the valve operating members. In the arrangement shown in Fig. 1, two valve casings 1, 2 secured to a plate 3 adapted to be screwed to a bench, are each provided with inlet and outlet passages 5, 6 with nipples 7, 8 for tubular connections and communicating by means of a valve chamber 11 which contains a diaphragm 10 adapted to be pressed against the orifice of the passage 5 in opposition to a spring 12, by a wedge member 16 acting through a ball 13. The wedge is carried by a lever 15 loosely pivoted in a bracket on the base plate 3 and formed with a forked end 17 or the like to carry a blowpipe when not in use, the weight of the blowpipe causing the wedge to close the valves to cut off the gas supply. The lever is raised by a spring, allowing the valves to open, when the tool is removed. A small burner 18 may be connected to one of the gas supply passages 5, the flame being protected by a shield 20 and regulated by a screw valve 21 provided with a screw cap 22. The wedge faces may be arranged to operate the valves one in advance of the other. They may also terminate in flat parallel surfaces so that the gas pressure acting on the diaphragms is unable to effect movement thereof. In the arrangement shown in Fig. 3, each valve chamber 27 contains a flexible diaphragm 26 carrying a central spindle 28 formed with valve closure members 29, 30 adapted to engage seatings at opposite ends of a passage 34 of slightly larger diameter than the spindle. When the wedge 41 is out of action, a spring 35 within the chamber 27 presses the diaphragm so as to open the valve 29. the valve 30 acting as a throttle for high pressure gas admitted through the passage 33. A heavier spring 36 acting .on the opposite side of the diaphragm is located in an extension 37 of the chamber 27 and bears against a plunger 38 with a stem 39 carrying an adjustable extension 31 adapted to engage the wedge 41, so that by the action of the wedge the pressure of the spring 35 may be overcome and the valve member 29 pressed on to its seating to cut off the gas supply. A cursor 46 operated from the diaphragm may indicate pressures on an external scale 45. The inlet and outlet passages 33, 34 may terminate in nipples as in the previous example. As shown in Fig. 4, the blowpipe may be hinged at 49 to a bracket 47 and be brought into action by a pedal or the like 55, the valve housing being secured beneath a baseplate 46<a> and the wedge operating-member 53 being carried by a bent-arm 52. An adjustable weight 50 raises the blowpipe when the pedal 55 is released.