Abstract: A method and apparatus of controlling the direct injection of fuel directly into the combustion chamber of an engine by a charge of gas, wherein the control of the timing of injection of the fuel includes at the commencement of start up of the engine, adjusting the timing of injection so injection occurs at a timing earlier in the combustion chamber cycle than the normal timing of injection for idle running; and in response to the engine reaching a predetermined speed or rotation during start up, the timing of injection is progressively adjusted each engine cycle towards the normal timing of injection at idle running.

Abstract: A nozzle for the injection of liquid fuel by compressed gas which produces a generally circular first array of gas-entrained fuel droplets and a second array of gas-entrained fuel droplets within the first array. The preferred nozzle has an outwardly opening poppet valve with notches (65) on the perimetal edge of the valve head (48). The division of the fuel-gas charge into two arrays reduces penetration of the charge into the combustion chamber with beneficial effect on combustion efficiency and exhaust emissions. Also disclosed is an arrangement in which an un-notched poppet valve co-operates with a notched valve port to similarly obtain division of the fuel-gas charge into two arrays.

Abstract: A fuel injection method and apparatus for in-cylinder injection in an internal combustion engine. Compressed air is used to inject the fuel through an injection nozzle (43) particularly shaped so that different fuel spray patterns are produced at high and low fueling rates. At higher rates of fueling corresponding to higher engine loads the fuel spray pattern is narrower and penetrates further into the cylinder volume whereas at lower rates of fueling corresponding to lower engine loads the fuel spray pattern is wider, less penetrating and relatively more confined. By appropriate selection of nozzle shape the spatial distribution of the fuel spray droplets can be made to vary favorably over a range of engine loads.