GB577827A - Improvements relating to liquid fuel pumps - Google Patents

Abstract

577,827. Fluid-pressure servomotors. LUCAS, Ltd., J., and IFIELD, R. J. June 23, 1942, No. 8608. [Class 135] The delivery-regulating member of a liquid fuel pump is actuated by a piston n which is movable within a cylindrical chamber o by means of pressure liquid under the control of a valve y which is moved in one direction by a spring v in response to movement of the piston and in the opposite direction by means responsive to one or more different and variable pressure or temperature conditions. In the form shown in the Figure, the piston n is connected by a plunger m to the swash-plate c of a rotary cylinder pump, the end of the chamber o adjacent the pump being supplied with liquid under pressure from the source which supplies the inlet j of the pump, this liquid flowing from the interior of the pump through a passage q with a restriction r and a port q<1>. The ends of the chamber o are connected by a passage f having at one end a seat u for the valve y carried by a pivoted lever w engaged by the end of the spring v. This lever is also engaged by the stem 5 of a diaphragm 4 separating a compartment 2, which is subjected to variable boost pressure, from a compartment 3 subjected to the exhaust back pressure of a prime mover supplied with liquid fuel by the pump. The compartment 3 also contains a capsule 7 subjected to variable temperature conditions. In one modification, the valve lever w is operated by an adjustable cam actuated by the swash-plate. In another, the swash-plate is adjusted by rotary motion derived from a fluid - operated rack - and - pinion mechanism responsive to the controlling pressures.