GB153941A - Improved variable stroke reversible rotary pump and means for controlling same - Google Patents

Abstract

153,941. Shepherd, F. W. H. July 21, 1919. Eccentric-actuated pumps; stroke, varying; revolving-cylinder pumps; waste liquid, catching.-A variablestroke reversible rotary-cylinder pump comprises a rotor 2 mounted on a central valve 1 and carrying a number of radial cylinders in which pistons 3, 3a are reciprocated by an adjustable eccentric two-part track 6, 7 engaging rollers 5 carried by the pistons. Leakage liquid collecting in the vessel 10 is thrown by the cylinders against plates 14, 15 from which it falls into the tank portion 8 of the casing 9. The leakage is returned to the pump bv a pipe 16 connected to the valve 1. The stroke of the pistons may be varied from zero to a maximum by moving the eccentric 6, 7 transversely of its axis by means of stroke-controlling pistons in cylinders 23, 24 connected by pipes 17, 18 to the valve ducts. A lever 25 is pivoted on a slidable member 32 connected by rods and brackets 37 to the eccentric. One end of the lever 25 is connected to a telemotor &c., and the other end to a part of the apparatus operated by the pressure liquid of the pump, such as the tiller of a rudder, to act as a cut-off. The pump is started from zero stroke position by moving one end of the lever 25 slightly, thereby moving the member 32 and the eccentric against the action of one or other of the springs 33, 34. The pump now delivers pressure liquid to one or other of the cylinders. 23, 24, according to the direction of rotation of the pump, and the consequent movement of the piston 23a against the action of the spring 35 completes the movement of the eccentric. The stroke is automatically adjusted so that the power delivered from the pump never exceeds the pre. determined power of the motor driving the pump. The central valve 1 is axially adjustable.