GB750493A - Improvements in or relating to internal combustion engines - Google Patents

Abstract

750,493. Two-stroke engines; fuel injectors; regulating. NESTOROVIC, M. N. Feb. 4, 1952 [July 16, 1951], No. 2903/52. Classes 7(2), 7(3) and 7(6) The working cylinder (or cylinders) 55, has practically no clearance between the piston and cylinder head at top dead centre, fuel under pressure and high-pressure air from a compresor being fed into the cylinder during a portion of the piston stroke. The fuel is burnt at substantially constant pressure and temperature. In the figures, a four-stroke engine has working cylinders 55, 56 and compressor cylinders 50, 51, which supply a manifold 70, which may have a heating coil 58, supplied with exhaust gases from the engine. Inlet valves 53 are controlled so that, at reduced loads on the engine or compressor, they remain open during the beginning of the compression stroke. This control is effected by axial movement of a camshaft 54 through linkage 69 acted on by a piston 68 under pressure of the air in the manifold 70. The opening of the exhaust valves 57 may also be varied. Sleeve valves may be used. The cylinders 50, 51 are preferably cooled, and may compress the air in series. In addition to a sparking plug 88, in each engine cylinder head, there is a burner 59 supplying combustion gases (see Fig. 2). The burner contains an injection valve 74 provided with helicoidal ribs 75 on an outer conical face. Around the valve 74 is a piston 76 with a conical front portion so that, under the action of a coil spring 77, the piston regulates, and can close, the conical space in the body of the burner 73, except for a small clearance. Air under pressure, from the manifold 70, enters through a passage 78, and fuel through an inlet 81 leading to a duct 82 and a groove 83 behind the cone of a needle valve 79. The position of the latter is controlled through linkage acted upon by the cam shaft 60. The helicoidal grooves cause turbulent entry of the fuel, in a direction opposite to the swirl of the air flow. Fuel leaking past a labyrinth 85 passes through a drain 86. A compressed air bottle 72, charged from the compressor may be used for starting up the engine, by opening a cock 87, which admits compressed air to the burner. Then the cam shaft 60 is moved axially, to bring a cam follower 61 on to the widest section of the cam 60 and actuate the burner piston 76, and needle valve 79 through linkage 61...65. The sparking plug 88 is only used for starting- up purposes, but the burner flame is on continuously, but is varied in intensity. A centrifugal governer 67 is connected, through a bell-crank lever 66, with the linkage 61...65. The Specification states that a hydraulic or electrical control system may replace the mechanical linkage described. Safety valves 71 open under excessive cylinder pressure.