GB190173A - Improvements in four stroke cycle internal combustion engines for use in aircraft - Google Patents

Abstract

190,173. Durand, E. H. M. E. Dec. 12, 1921, [Convention date]. Regulating; valve-gear; valves. - Fourstroke engines for use on aircraft are arranged to work with a supplementary charge at high altitudes by employing the front side of the piston to compress air or mixture. I n a single - cylinder engine, a sliding plate c<1>, Fig. 1, is used to close the front end of the cylinder, the connecting- rod a<1> passing through an oscillating closure a<2>. The pump supplies to a reservoir between the valve b<2> and the cylinder valve h, the latter being controlled by an axially adjustable cam i<1>, either automatically or by hand according to barometer indications. Mixture may be drawn from the main carburettor, or air may be forced through a supplementary carburettor, or air only may be supplied as the added charge. The pump valves and the admission valves h may be replaced by an oscillating plug valve. In a V-engine, the oscillating plug valve m, Fig. 6, is placed in a conduit b' connecting the two cylinders; a pipe b<8> leads to the crank case, in which the supplementary charge is compressed; the valve controls delivery to the two cylinders alternately and also admits the charge to the crank case. In a four-cylinder engine with the front ends closed as in Fig. 1, a ported cylinder is used to control all the pump spaces; each cylinder combustion space receives a charge from two pump spaces. In a revolving-cylinder engine, the front ends being closed by sliding plates c', Fig. 14, a ring valve q controls the pump spaces, the valve being driven from an internal wheel c<3> on the crank case through the pinions r, t; with a sevencylinder engine, the valve rotates at seven-eighths of the speed of the engine. Each combustion space is supplied from two pump spaces.