GB494691A - Improvements in two-stroke internal combustion engines - Google Patents

Abstract

494,691. Two -- stroke engines. BENNET, C. W. H. D. April 30, 1937, Nos. 12309 and 12310. Convention dates, April 30, 1936 and March 30,1937. [Classes 7 (ii) and 7 (vi)] In a two-stroke engine, the crank-shaft, which is in driving connection with the piston or pistons and is rotated relatively to the cylinder or cylinders, forms a ported part of each cylinder head and receives the direct pressure of the combustion within each cylinder. The combustion chambers are cylindrical and located between the piston or pistons and the crank-shaft. As applied to a radial engine, the combustion chambers are disposed between differential pistons 5, Fig. 6, and the crankshaft 9 to which the pistons are linked by connecting rods 7. A recess 18 in the crank-shaft puts the combustion chambers successively in communication with passages 17 each leading to a precompression chamber in the preceding cylinder above the piston 5, the arrangement ensuring an increasing discharge pressure as the charge is forced into the combustion chamber for scavenging. The precompression chamber may be larger than the combustion chamber. Opposite the recess 18 in the crank-shaft 9 is an igniter 22 which may take the form of a simple passage permitting the burning gases in one cylinder to fire the charge in the next one. In a modification, Fig. 9, the crank-shaft terminates in a ported boss 9a surrounded by a stationary sleeve 30 on which the transfer passage 17 is mounted. Passages 32, 15a in the crank-shaft place the passage 17 in communication with either an enlarged chamber 34 in the crank-shaft or an air inlet 31 and the time and dimensions of the opening of the passage 17 into the passage 32 are determined by a two-part sleeve 35 between the sleeve 30 and the boss 9a adjustment of the parts of the sleeve determining the position and size of the opening in the sleeve. A fuel injector may be disposed in the crank-shaft in the case of a Diesel engine, or a fuel nozzle be similarly disposed or a carburetter supply the inlet 31.