Abstract: A method of injecting liquid fuel to an engine which includes delivering a quantity of fuel into a conduit and propelling the fuel along the conduit by a pulse of gas under sufficient pressure to discharge the fuel from an open nozzle into an engine induction passage, or combustion chamber. The pressure and quantity of gas are preferably sufficient to cause the fuel to issue from the nozzle at or near sonic speed. The duration of the pulse of gas may be varied with a variation in the quantity of fuel to improve the fuel metering accuracy with engine load changes.

Abstract: A method and apparatus for metering fuel to an engine wherein a continuous supply of fuel is provided by a pump (14) to a fixed capacity chamber (11) and gas under pressure is admitted periodically to said chamber to maintain in the chamber a pressure not greater than the fuel pressure, so that fuel will flow into the chamber as long as there is a pressure differential between the gas in the chamber and the fuel supply. A delivery port (20) in said chamber is open for substantially the duration of the period that gas is admitted to the chamber so that the fuel in the chamber at the time of admission of gas thereto, and fuel entering the chamber during the period of admission of gas, is delivered from the delivery port (20) to the engine. The pressure differential between the fuel supply and the gas in the chamber is controlled in accordance with the fuel demand of the engine to control the quantity of fuel delivered each cycle to the engine.

Abstract: In a spark ignition engine, fuel is injected directly into the cylinder volume. In order to obtain improved levels of combustion efficiency and reduced emissions the position of the fuel cloud within the cylinder volume is varied with engine load by controlled variation of fuel injection pressure. In particular, there is disclosed a method and apparatus for injection of fuel by compressed air where the position of the fuel cloud within the cylinder volume is controlled by conjoint control of fuel and air injection pressure. The invention has particular application to two-stroke cycle engines.

Abstract: A method of injecting liquid fuel to an engine comprising delivering a quantity of fuel into a conduit and propelling the fuel along the conduit by a pulse of gas under sufficient pressure to discharge the fuel from an open nozzle into an engine induction passage, or combustion chamber. The pressure and quantity of gas preferably being suficient to cause the fuel to issue from the nozzle at or near sonic speed. The duration of the pulse of gas may be varied with the variation in the quantity of fuel to improve the fuel metering accuracy with engine load changes.

Abstract: A method and apparatus for metering fuel to an engine wherein a continuous supply of fuel is provided by a pump (14) to a fixed capacity chamber (11) and gas under pressure is admitted periodically to said chamber to maintain in the chamber a pressure not greater than the fuel pressure, so that fuel will flow into the chamber as long as there is a pressure differential between the gas in the chamber and the fuel supply. A delivery port (20) in said chamber is open for substantially the duration of the period that gas is admitted to the chamber so that the fuel in the chamber at the time of admission of gas thereto, and fuel entering the chamber during the period of admission of gas, is delivered from the delivery port (20) to the engine. The pressure differential between the fuel supply and the gas in the chamber is controlled in accordance with the fuel demand of the engine to control the quantity of fuel delivered each cycle to the engine.

Abstract: A fuel injection nozzle for use in direct injection of fuel to an internal combustion engine, the injector nozzle comprising a body having a longitudinal fuel passage terminating in a port which in use communicate the fuel passage with the combustion chamber of the engine. A valve element to co-operate with a valve seat provided in the port to control fuel flow to the combustion chamber, and a fuel spray directing surface in the port extending downstream from the valve seat. The body including a cavity between the spray directing surface and that part of the body through which the fuel passage passes, with the cavity being shaped and located to restrict the area for conductive heat flow from the spray directing surface to fuel passage area of the body. The restriction of the heat flow maintains the spray directing surface at a temperature to combust particles of combustion products deposited thereon.

Abstract: A fuel metering apparatus having a metering chamber to hold fuel for subsequent delivery to an engine and a rigid metering member projecting into said chamber and linearly movable relative to the chamber to vary the extent of projection of the metering member into the chamber to thereby control the quantity of fuel displaceable from the chamber for delivery to an engine. An inextensible flexible member between secured to the metering member and to a motor that operate in accordance with the engine fuel demand, the motion of the motor being transmitted to the metering member through the inextensible flexible member. This inextensible flexible member preferably being adjustably coupled to the motor so the limit of movement of the metering member may be set as required.

Abstract: A method of injecting fuel to an internal combustion engine (9) comprising introducing a metered quantity of fuel into a scheduling chamber (32) from where it is injected by pressurized gas into the combustion chamber or induction system of the engine (9). The rate and/or time of introduction of the fuel to the scheduling chamber (32) is controlled in relation to the period of injection to achieve a predetermined fuel distribution in the combustion chamber at ignition. An axial stratification of fuel in the combustion chamber can be produced.

Abstract: Method and apparatus for metering and injecting fuel to an internal combustion engine, particularly suited to in-cylinder injection. Fuel and compressed gas are supplied separately to a valved port (71), with the valve (72) shutting off fuel passages (68) and air passages (66) or allowing fuel and gas to pass through the port (71) and be expelled as a mixture of fuel entrained in the gas. The pressure differential between the fuel and gas at the annular cavity (91) is regulated to control the amount of fuel injected. The position of introduction of the fuel to the gas at the port (71) may be controlled to vary the geometry of the fuel distribution in the resultant spray.

Abstract: In a two-stroke spark ignition engine, fuel is injected through the cylinder wall at a location opposite to and above the level of the exhaust port (120). The fuel is delivered in the form of a number of streams such as, for example, streams (60), (61), (62). One of the streams (60) is directed upwardly across the cylinder to deliver fuel towards the combustion chamber cavity (122). This stream (60) is arranged not to impinge on the spark plug (123) but is caused to create a fuel rich cloud within the cavity (122). Streams (62) are directed downwardly and outwardly from the injection location and an optional stream (61) may be directed across the cylinder towards the exhaust port side of the cylinder.

Abstract: A fuel metering and injection system for an internal combustion engine circulates fuel through a metering chamber (11) via valved fuel inlet and fuel outlet ports (25, 26) to prepare a metered quantity of fuel. Compressed gas is introduced into the metering chamber through a valved air inlet port (14) to displace the metered fuel and deliver it to the engine. Phasing of the valves is controlled to ensure that the fuel inlet and outlet valves (60, 61) are closed prior to opening of the air inlet valve (16), and that on completion of the injection phase residual gas in the metering chamber (11) is expelled through the fuel outlet port (26).

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.

Abstract: A fuel metering apparatus having a metering chamber to hold fuel for subsequent delivery to an engine. A rigid metering member projecting into the chamber linearly movable relative to the chamber to vary the extent of projection of the metering member into the chamber to thereby control the quantity of fuel displaceable from the chamber. An inextensible flexible member secured to the metering member and a motor operated in accordance with the engine fuel demand, the motion of the motor being transmitted to the metering member through the inextensible flexible member. The inextensible flexible member is preferably adjustably coupled to the motor so the limit of movement of the metering member may be set as required.

Abstract: Method and apparatus for fuel injection to an internal combustion engine is disclosed. Gas is supplied to a fuel holding chamber to maintain a reference pressure which is above atmospheric pressure in the fuel holding chamber. A metered quantity of fuel is delivered into the holding chamber against the reference pressure. Communication is established between the holding chamber and the engine, and the supply of gas to the holding chamber is maintained while the communication exists so the pressure of the gas is sufficient to displace the metered quantity of fuel from the holding chamber to the engine.

Abstract: The fuel injection apparatus includes fuel a fuel metering chamber, an air supply chamber and a further chamber formed in a rigid body. A metering member is slidable within the fuel and gas chambers and passes through the further chamber. The amount of fuel fed to the metering chamber via valve means is controlled by the position of the metering member. An increase in pressure in the air supply chamber opens a valved passage in the metering member and the air expels the fuel from the metering chamber via check valve means. The further chamber collects any leakage of air or fuel past bearing means that receives the metering member.

Abstract: A method and apparatus for delivering metered quantities of liquid wherein the liquid is circulated through a chamber to fill the chamber with liquid and circulation is temporarily terminated with the chamber filled with liquid. While circulation is terminated gas under pressure is admitted to the chamber to displace liquid therefrom through a discharge port. The quantity of liquid displaced is controlled by regulating the volume of the chamber and/or by regulating the relative disposition in the chamber of the point of entry of the gas and point of discharge of the liquid.