GB405980A - Improvements relating to the injection of fuel to the cylinders of internal combustion engines - Google Patents

Abstract

405,980. Fuel injectors. MILLAR, W. H., 19, Sandford Avenue, Bloomfield, Belfast. July 12, 1932, No. 19660. [Class 7 (iii).] An improved fuel injector is actuated by the cylinder pressure on a piston 14 which is controlled by a spring 15 (Fig. 1). Integral with the piston 14 is a combined nozzle and plunger 18 which works in a rotatable sleeve 19 which has suction ports 20 communicating with a suction space 21 and a fuel chamber 22. The plunger has two helical ledges 18a at its upper end that, when the piston is forced upward by the cylinder pressure, cover the ports 20 and trap a measured quantity of fuel in the chamber 22, the amount of which is regulated by the angular position of the sleeve. The fuel is held under pressure until a timing valve 25 operated by a cam 35 uncovers the ports 27 and admits the fuel to the nozzle orifice 23, 23a, and to the cylinder. At the end of the injection period the timing valve 25 rises to withdraw residual fuel from the nozzle and prevent dribble. In a modified construction the actuating piston is external to the cylinder but connected thereto by a pipe and an annular passage around the nozzle. In another modification (Fig. 5), the fuel is measured by adjusting the axial position of an opposed plunger 74 under the control of a spring 75 and balanced by a second piston 83 connected to the cylinder. In this case the timing valve is kept stationary but is axially adjustable by hand and the movement of the actuating piston automatically times the injection.