GB1331070A - Heat engine and a method of putting this engine into action - Google Patents

Abstract

1331070 Six-stroke cycle I. C. engine M MILISAVLJEVIC 16 Dec 1970 [17 Dec 1969] 59661/70 Heading F1B A six-stroke cycle heat engine has a combustion chamber 14 in which a fuel-air mixture is burnt under constant volume conditions and then transferred to the space above a piston 4 reciprocating in a cylinder 1. The engine comprises an inlet valve 9 through which fresh air is induced during the downward stroke of the piston 1, a valve 15 in the transfer passage 13 and an exhaust valve 19 in the combustion chamber 14. All the valves are operated by cams 11, 17 and 21 respectively which are mounted on a cam-shaft driven from the crankshaft 5 at one-third of the speed thereof, each of the valves being spring-biased to the open position. A fuel injector and sparking plug, also controlled by the crank-shaft are mounted in the combustion chamber wall. The cycle of operation is as follows: At the beginning of a first downward stroke of the piston, exhaust valve 19 and transfer valve 15 are closed and inlet valve 9 is open. At the beginning of the first upward stroke, inlet valve 9 is closed, transfer valve 15 is opened and exhaust valve 19 is opened briefly to allow scavenging of the combustion chamber and then closed, so that the air above the piston fills the chamber and is compressed therein. The transfer valve is then closed and the inlet valve opened as the piston commences to move downwardly on its third stroke. During this stroke the fuel is injected into the combustion chamber and the mixture is ignited. Combustion continues throughout the third stroke of the piston and the ensuing fourth stroke during which the air induced in the third stroke is compressed in the space above the piston. As the piston begins to move downwardly on its fifth stroke, the transfer valve is opened, the inlet and exhaust valves remaining closed and the gases from the combustion chamber expand into the cylinder and continue burning there, as the piston makes its working stroke. During the final stroke of the cycle, as the piston moves upwardly, the inlet valve remains closed, the transfer valve remains open and the exhaust valve is opened so that the burnt gases are expelled. In a modification of the cycle, the exhaust valve is not opened momentarily as the piston moves downwardly on its first stroke, so that the remaining burnt gas is drawn into the cylinder and heats the incoming air.