Patent GB-153256-A (GB)
Title: Improvements in two-stroke cycle internal combustion engines
IPC: F01L5/08
Filed: 1920-10-26
Abstract: 153,256. Mathauser, S. Oct. 31, 1919, [Convention date]. Valves,. valve-gear.- A piston 3 reciprocates in the interior of a second piston 2 surrounding which is a sleeve valve 4 reciprocating in the interior of a slide valve 5 which closes upon a seat forward on a partition 7 in the head of the cylinder 1. A charge of combustible mixture is drawn through a passage 10, Fig. 3, into a pump space above the piston 2 when the valve 5 is moved away from its seat on the partition 7, the pump charge being transferred to the combustion space between the pistons after the valve 5 is seated and the sleeve valve 4 has moved away from its seat upon the head of the piston 2. Compressed charges enter the combustion space through the ports 8 in the piston 2. The engine shown in Fig. 3 has exhaust. ports at both ends of the cylinder, the ports 11 registering with ports in the sleeve valve 4 and the piston 2, and the second series of exhaust ports 9 registering with ports in the valves 5, 4 and the ports 8 in the piston 2. A sparking-plug is located at 6, the charge in the combustion chamber being ignited when the ports adjacent the opening 6 are in line. The piston 2 is connected by a lug 12 carrying a roller 12' to a grooved cam 14 mounted on the crank-shaft. The piston 2 remains in its uppermost position until the main piston 3 has almost completed its working stroke. The piston 2 then moves downwards drawing in behind it a pump charge and at the same time placing the port 11<1> in register with the exhaust port 11. During its downstroke, the piston 2 draws with it by friction the sleeve valve 4 which itself draws down by frictional contact the outer valve 5. When the piston 3 has almost reached the limit of its upstroke, the piston 2 is moved rapidly towards the partition 7 and expels the pump charge into the combustion space. The return movement of the piston 2 effects the return movement of the valves 4, 5 which come to rest when the valve 5 seats upon the partition 7 the friction between the piston 3 and the valve 4 being insufficient to overcome the friction between the two valves, thus preventing the valve 4 from closing upon its scat during the transfer of the charge to the combustion space. After the transfer of the charge, the valve 4 is moved into its uppermost position by a cam 27 which engages a lug 13 extending from the underside of the valve. A modified construction of two cylinder engine is described in which water is injected into the burnt gases during the return stroke of the main piston. The engine works upon the continuous-combustion principle and fuel is injected through an orifice 6, Fig. 11, into highly compressed air in a chamber 20 formed in the head of the piston 2. The chamber 20 comprises a yielding piston 21 which advances during the exhaust period to expel the burnt gases. Each piston 2 carries two extensions with arc-shaped grooves which are engaged by a, pin on each connecting-rod to effect the forward and return movements of the piston. In this construction, the terminal exhaust ports are dispensed with and the exhaust port 9 is opened only when the pressure during the return stroke of the piston reaches that of the atmosphere. The pins on the connecting-rods impart the final upward motion to the valve 4.