GB673923A - Improvements in fluid control valve devices - Google Patents

Abstract

673,923. Valves. ETABLISSEMENTS MERLIN & GERIN, and LATOUR, A. July 1, 1947, No. 17280/47. Class 135 [Also in Group XXXV] In a valve device for controlling the flow of compressed fluid comprising electromagnetic means for opening the valve, the valve is maintained open by the action of either the combined effects of the electromagnetic means with reduced current and the impact of the fluid escaping through the valve orifice, or the sole effect of the impact of the escaping fluid when the reduced current has ceased. The valve 7, Fig. 1, is attracted downwards by a coil 2 when a switch 3 is depressed. A relay coil 5 is then energized to open a switch 6 so that current passes through a resistance 4, the reduced current, together with the impact of the fluid escaping through the valve orifice, then holding the valve open. In a modification, the initial opening current is obtained from a condenser, the reduced current then being the normal current supplied through a resistance. The coil 2, carried by the valve, may move between the poles of a permanent or electro-magnet, while the valve may comprise a cup loosely surrounding a nozzle in order to gain the full impact of the escaping fluid. As shown in Fig. 6, the valve is carried on a spring-loaded lever 42 actuated by an electro-magnet 45. The nozzle 48 carries a piston ring 49 sliding and controlling ports 47 in a cylinder 46 forming the valve, while a duct 55 through the end of the cylinder leads to a bellows 54 mounted on a ball joint 57. This arrangement allows of a tighter closing and a quicker opening of the valve. The bellows may be dispensed with, while the piston rod 39 of a piston 38 forming part of a pneumatic servomotor actuating a valve may be hollow so that air flowing out of it ejects air from the cylinder 37 through the nozzle and increases the impact on the valve.