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: An internal combustion engine in-cylinder fuel injector nozzle having a body having a fuel passage terminating in a port that, in use, communicates the fuel passage with an engine combustion chamber. The port has an annular seat therein and a valve element also having an annular seat co-operates with the seat in the port to control fuel flow therethrough. An annular flow directing surface extends downstream from each of the annular seats, and each flow directing surface is contoured to blend smoothly with its respective seat.

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 method of operating a two-stroke spark ignition engine (9) wherein the fuel is injected directly into the engine combustion chamber (22). The timing of the injection of the fuel and the ignition of the fuel charge are varied according to engine load and speed conditions. Under low load and speed conditions substantially all the fuel is injected after closure of the exhaust port (20) and the fuel charge is ignited between 40 and 70 degrees of crank angle rotation before the top dead center point of the engine cycle. Under high load conditions substantially all the fuel is injected before exhaust port closure.

Abstract: A two stroke cycle engine 10 with an exhaust gas treatment catalyst. Separate reducing and oxidizing catalyst portions 126 and 127 are provided to treat different portions of the exhaust gas exhausted during each exhaust period. The portion of the exhaust gas high in NOx, usually that first exhausted upon initial opening of the exhaust port, is directed to be treated by the reducing catalyst 126 and the remainder of the exhaust gas is directed to be treated by the oxidizing catalyst 127.

Abstract: A fuel injected internal combustion engine and a method of operating same, the engine having a fuel injection system wherein fuel is injected through a selectively openable injector nozzle directly into a combustion chamber of the engine by gas from a pressurized gas supply system. While the engine is being cranked during start-up of the engine, the injectory nozzle is opened to communicate said combustion chamber with the gas supply system. Gas compressed within the combustion chamber enters into the gas supply system to assist in rapidly establishing gas pressure for subsequent operation of the fuel injection system.

Abstract: A fuel injection system for a multi-cylinder internal combustion engine, which includes a rigid elongated unitary member incorporating a gas supply duct, a fuel supply duct and a fuel return duct, each of which extends in the direction of elongation of the unitary member. A separate fuel metering device and fuel injecting device is provided for each engine cylinder. The fuel metering device is arranged to deliver metered quantities of fuel to the fuel injection device and is in communication with the fuel supply and fuel return ducts so that fuel can be circulated through each of the fuel metering devices. The fuel injecting devices are each in communication with the gas duct and communicable with one of the engine cylinders. The fuel injection devices are adapted to effect delivery of a metered quantity of fuel entrained in gas supplied from the gas duct when the fuel injecting device is in fluid communication with a cylinder.

Abstract: A two-stroke spark ignited engine (10) with direct fuel injection (14) and an exhaust gas treatment catalyst. A separate catalyst unit (23) is provided for each combustion chamber (11) and is located at or adjacent each exhaust port (15) from that chamber and that during a cycle of each combustion chamber (11) the catalyst unit (23) of that combustion chamber (11) is exposed only to exhaust gases which change from chemically reducing to chemically oxidizing during the cycle. An engine which has exhaust gases which are overall chemically oxidizing can thus nevertheless have the NOx constituents of the gases reduced.

Abstract: A two stroke internal combustion engine (5) having a transfer port (9) and an exhaust port (8) in a cylinder (6) which are opened and closed in a timed relationship by the reciprocating movement of a piston (7). The exhaust port (8) communicates with an exhaust passage that is tuned to provide a pressure pattern in the exhaust passage that will create at the exhaust port (8) a predetermined pressure pattern while the exhaust port (8) is open. Coolant is supplied to the exhaust passage when the engine is subject to increasing transient load conditions, at engine speeds below the tuned speed, and at a controlled rate to establish a tuned state in the exhaust passage during the transient condition.

Abstract: A multi-cylinder engine block for an engine operating on the two-stroke cycle and having two or more adjacent cylinder bores (10,11,12) with the axes of the bores parallel and in a common longitudinal plane. Each cylinder bore having an exhaust port (20), and an exhaust passage (21) extending from each exhaust port (20) to an external surface (22) of the block in a direction generally at right angles to said common longitudinal plane (25). Two transfer ports (27,28) being provided communicating with the same cylinder bore on either side of the exhaust port in the direction of said common longitudinal plane. Each transfer port communicating with a respective transfer passage. The transfer ports (27,28) not extending beyond the common longitudinal plane (25), and the transfer passages (26,23) adjacent the respective transfer ports (27,28) extending in a direction generally tangential to the cylinder bore.

Abstract: A fuel injection apparatus for delivering a metered quantity of fuel to an engine comprising a valve controlled port through which the metered quantity of fuel is delivered to the engine the valve being resiliently urged to a position to close said port. Electromagnetic means operable when energized to displace said valve member from the closed position to permit delivery of the metered quantity of fuel through the port to the engine. The electromagnetic means including an armature member movable in a first direction in response to energizing of the electromagnetic means to effect the opening of the port. The armature having a limited free movement in the first and the opposite directions independent of the valve member when the electromagnetic means is not energized and the valve member is in the port closed position.

Abstract: A spark ignited four stroke cycle internal combustion engine having variable volume combustion chamber, ignition means to provide an ignition point in said combustion chamber, a valve controlled inlet port communicating the combustion chamber with an air induction passage through which air flows to the engine. The induction passage including a wall shaped to direct at least part of the air flowing along said wall portion when the port is open in a generally helical path about the port axis and when the port is open, the air flowing is directed into the combustion chamber to establish therein a generally helical air flow. A fuel injector nozzle located to deliver fuel into the induction passage on the opposite side of the inlet port axis to said wall portion of the induction passage and on a trajectory through the port when open to form an ignitable fuel cloud at the ignition point.

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: Improvements in fuel injection nozzles for spark ignited internal combustion engines enabling a metered quantity of fuel entrained in a gas to be delivered into a combustion chamber to optimize the efficiency of operation of the engine. The fuel injection nozzle has a port (11) and a valve (15) movable relative to the port (11). Port (11) and the valve (15) have respective annular sealing faces (13) and (18) defining an annular frustoconical shaped throat (25) when the nozzle is open for the flow of metered fuel therethrough. The nozzle has a shroud (20) extending from the port (11) surrounding the periphery of the valve (15) when the nozzle is open and defining a delivery passage 27 downstream of the throat in the direction of fuel flow towards the combustion chamber. The delivery passage 27 is configured to be purged of fuel after each fuel delivery cycle to prevent carbon build-up in the nozzle.

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 method of operating a two-stroke spark ignition engine (9) wherein the fuel is injected directly into the combustion chamber (22). The timing of the injection of the fuel is varied according to engine load and speed conditions. Under low load and speed conditions at least 80% of the fuel is injected after closure of the exhaust port (20) whereas under some high load conditions at least 80% of the fuel is injected before closure of the exhaust port (20). The method may also comprise adjustment of ignition timing so that, in conjunction with low load and speed conditions, ignition occurs at least 5.degree. of crankshaft rotation after commencement of fuel injection and up to 70.degree. before top dead center of the engine cycle.

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.