GB190517874A - Improvements in or relating to Internal Combustion Engines. - Google Patents

Abstract

17,874. Rollason, A. Sept. 4. Gas and like engines. - To i ncrease the charges in four-stroke-cycle engines, to prevent premature ignition, and to facilitate scavenging, the cylinder or cylinders and the air pump are arranged co-axially. Fig. 1 shows an air-pump c disposed in line with and between a pair of tandem cylinders a, a<1>. The piston d of the air-pump is formed in one with the piston b, and is connected by outside rods e to the guide attached to the piston b<1>. The charges, which are fired alternately, are admitted through any suitable arrangement of valves constructed to admit a charge of air, then a charge of combustible, and lastly a further charge of air. During the admission strokes, air charges are drawn through the passages g and enter the cylinders through the inlet valves h, h<1>, while the combustible charge enters through any suitable controlling- valves n, n<1>. Towards the end of the suction strokes, compressed air is admitted to the cylinders from the chamber p when the inner face of the pump piston d uncovers the ports i. Air is compressed through the ports i into the chamber p by the inward movement of the pump piston d, the compression ceasing when the piston overruns the ports i. The air remaining in the cylinder c after the ports i are closed serves to cushion the movement of the reciprocating parts. On the in stroke of the piston d, air enters the cylinder c through the valve l and ports i. Air drawn into the pump cylinder through the valve k and port f during the out-stroke of the piston d is compressed into the passages g on the return stroke and used for scavenging.