GB536101A - Improvements in or relating to free-stroke piston internal combustion engines - Google Patents

Abstract

536,101. Regulating; oil engines. SULZER FRERES SOC. ANON. Nov. 1, 1939, No. 29151. Convention date, Nov. 15, 1938. [Classes 7 (iii) and 7 (vi)] In a free-stroke piston engine, the fuel is injected in accordance with the pressure in the working cylinder by a pump which is positively actuated on its delivery stroke by means controlled by an impulse-transmitter influenced by the cylinder pressure. In the form shown in Fig. 1, the engine pistons 3 are connected to aircompressors 2 supplying a reservoir 4 connected to the inlet pipe 4<1>, exhaust occurring at 5, and fuel is injected at 30 by a pump 26 which is actuated by a constant air or gas pressure supplied by a pump 23 and pipe 17 past a valve 16, which is controlled by a lever 15 and plunger 7 acted on by the cylinder pressure through a pipe 6<1>. Fuel is supplied to the chamber of the pump 26, by a pump 27, which effects the return stroke of the pump 26, limited by an adjustable arm 31, when the cylinder pressure falls sufficiently for the plunger 7 to fall and move the valve 16 to cut off the pressure-supply pipe 17. The valve 16 may also be controlled by the pressure in the reservoir 4 acting on a plunger 11. The pressure in the exhaust pipe 5 may act on the plunger 7. In a modification, the delivery stroke of the pump 26 is effected by a spring which is released by a catch controlled by the plungers 7 and 11, the return stroke of the pump being effected by a cam driven from the pistons 3. A liquid column 46 may be interposed in the pipe 5<1>, Fig. 4, which also shows a safety device for preventing fuel injection when the cylinder pressure is too high. In such an event, the plunger 7 is raised sufficiently to move an additional control valve 51 so as to connect the pressure-supply pipes 17, 52, 53 to a vent 54, whereupon a piston 55 is moved by a spring 57 to connect a chamber 58 to a vent 63, thus allowing a piston 59 and valve 60 to lift and byepass the fuel from the pipe 61, so that no injection takes place at 30. The piston 55 is returned by a handle 64 to cause the valve 60 to close. The liquid 46, which may be lubricating oil, is suplied by a pump 50, against the pressure of air supplied at 49 past a non-return valve 48. In a modification, this non-return valve is arranged in the plunger 7.