GB300243A - Improvements in two stroke cycle internal combustion engines - Google Patents

Abstract

300,243. Boden, G. Nov. 9, 1927, [Convention date]. Two-stroke-cycle engines.-The power piston works within a sleeve 8 controlling air-inlet and exhaust ports 5, 7, and having an integral pump piston 8<a>. The centre of the crank pin, to which is attached the main connecting-rod 13, is on the same radial line from the shaft axis as the centres of the pins which receive the rods 14 driving the sleeve; in consequence the sleeve always moves in the same direction as the power piston, but has only one-third of the movement. Air is compressed in the crank case and by the underside of the piston 8<a>; at the end of the power stroke when the ports in the sleeve register with the ports 5, 7 in the cylinder and the power piston is at the lower end of the cylinder, this air is delivered past the valve 35 to scavenge the cylinder and fill it with air. The valve 35 may close either delivery passages 6, 34 or the air inlet passage 5. On the upstroke mixture-previously drawn into the upper pump chamber past the rotary controlled valve 30-is compressed and delivered to the cylinder through the valve-controlled passage 17 alter closure of the exhaust ports. The control means for the valve 35 may be coupled with means for controlling the air suction valves 3, 3<a>. Cylinder heads and arrangement of ports and igniters in cylinders.-The head 23 is attached to the cover 1<a> by ribs 22. The valve 24 and igniter 17 are arranged eccentrically in this head, the igniter in a screwed bore formed in one of the ribs.