GB344843A - Electrically operated reciprocating apparatus applicable to liquid delivery and control - Google Patents

Abstract

344,843. Regulating liquid levels. SCOTT, M. D., Denholme, Windmill Hill, Enfield, Middlesex, and MORRIS, J. N., 5, Redcliffe Square, London. Nov. 30, 1929, Nos. 36782/29 and 6400/31. Addition to 343,000, [Group XXVIII]. [Class 123 (i).] In an electrically operated pump for supplying a carburetter &c., in which the make and break of the circuit of the operating solenoid are effected by short-circuiting a magnetic flux, as described in the parent Specification, the float chamber is dispensed with, or is separate from the pump, or is formed by a continuation of, or enlargement of the pump barrel. The pump discharge pipe 68, Fig. 3, may discharge into a float chamber 71, or may be connected to the float chamber through a branch pipe 73. The float 74 may carry an iron mass 3 for short-circuiting the flux of a magnet 1 and so opening a switch 5, 6, 7 in the pump solenoid circuit when the liquid level rises. Alternatively, the float may carry a magnet for opening a switch against the action of a spring when the liquid rises, or for holding a switch closed when the liquid level is low. A fuse and an indicator, such as a lamp, may be arranged in the solenoid circuit. A vent in the float chamber may be closed by a buoyant valve if the float chamber is flooded, or the vent may be closed by a valve carried by the float. Alternatively a cock may be provided in a vent pipe 72, or in the pipe 73, to permit the supply of fuel under pressure for starting &c. In a modification, Fig. 12, the float 89 is arranged in the pump barrel above the plunger 15, and carries an armature 3 for alternately short-circuiting the magnetic flux of magnets 1, 2 and so operating a switch 5, 6, 7 in the circuit of the operating solenoid 22. The pump sucks through a valve 86 and discharges through a valve 87, and, in normal working, an axial bore in the plunger is closed by the float. If the demand decreases, the float is held suspended by the liquid and maintains the switch open. In modifications the bore in the plunger is controlled by a ball valve, which may be gravityoperated, or may be held to its seating magnetically when the solenoid is energized. In a further modification the discharge pipe is arranged as a branch from the barrel above the plunger. The float chamber 114, Fig. 16, may form an enlargement of the pump barrel. An iron mass 3 carried by the pump rod 118 alternately shortcircuits the flux of the poles of magnets 1, thus operating a lever 5 pivoted at 115 and carrying a contact 6 engaging a contact 7 in the circuit of the solenoid 22. The float may be attached to the rod 118, or may engage projections 120 on the rod, to hold the plunger in the raised position if the liquid level rises, and so maintain the switch open. A chamber 106 contains a filter 111 through which the liquid passes twice before entering the pump barrel.