GB525067A - Improvements in and connected with fuel injection in internal combustion engines - Google Patents

Abstract

525,067. Oil engines. DAIMLER-BENZ AKT.-GES. Feb. 13, 1939, No. 4746. Convention date, Feb. 11, 1938. [Class 7 (iii)] In a petrol engine using spark-ignition and in which the fuel injection nozzle is located opposite to the ignition means, the jets of fuel issuing from the nozzle are of two kinds, viz., finely atomized and diffused jets which are directed through the combustion space, and solid or less diffused localized jets which are directed on to the heads of valves in the cylinder cover, into valve recesses, on to the piston head, and in some cases towards the sparking plug. The nozzle shown in Figs. 2, 3 and 4 has a cut-away portion 3 with three countersunk orifices 4, 5 therein for the localized jets, and three orifices 6 and 7 for the diffused jets. The inclinations of the passages leading to the orifices are given in the Specification. In Figs. 5 and 6 the nozzle is shown applied to a four-stroke cycle engine having two inlet valves 11 and two exhaust valves 13, fuel being injected during the early part of the suction' stroke. Fuel jets N from the orifices 7 are directed towards recesses 10 adjacent the valves 11, whereas the localized jet T from the orifice 6 is directed towards the piston. Diffused jets R from the orifices 5 traverse the combustion space and are projected against the piston face whilst the jet K from the orifice 4 is directed between two ignition plugs 18. Modified forms of fuel injector are described in which a central conical jet is controlled by a lift valve other jets issuing through passages around the valves. These passages may be uncontrolled or they may be controlled by the lift valve which closes on two seats in its motion in opposite directions. A conical spray may comprise a number of separate jets and in some cases a localized jet may penetrate a diffused jet. The valve timing and fuel injection periods are as follows:- The air inlet valve opens 30 degrees before the upper dead centre and closes 45 degrees beyond the lower dead centre, the exhaust valve opening and closing about 40 degrees before and 5 degrees beyond the upper and lower dead centres respectively. The fuel injection commences 25 degrees after, and terminates not more than 65 degrees after the commencement of the suction stroke. The method of fuel injection may be applied to a two-stroke cycle engine. Specification 487,013 is referred to.