Abstract: Apparatus for metering fuel and air for an engine, which apparatus comprises air flow measuring means which measures at least a part of the flow of air for the engine and which generates an electrical output that is proportional to the measured air flow, control means which receives the output from the air flow measuring means and which generates electrical output signals which vary in dependence upon the received signals, and an injector which injects fuel in response to the signals from the control means. Preferably the apparatus of the invention includes fuel dissipating means, such as a heat pipe or a sonic nozzle, for finely atomizing the injected fuel.

Abstract: A fuel injection system comprising a fuel injection nozzle having a fuel injection orifice, and a vibrator for producing atomization of the fuel injected by the nozzle, the nozzle being equipped at the inlet side of the orifice with a fuel retaining valve which is arranged to normally close the orifice and thus prevent the injection of fuel by the nozzle and which is adapted to move away from the orifice when the vibrator is activated and thus allow the injection of fuel by the nozzle, the nozzle being provided with a mechanical stop device so positioned at a distance from the orifice and in the path of the valve as to limit the maximum possible travel of the valve away from the orifice to that giving a maximum predetermined amount of fuel injection by the system.

Abstract: A heat exchanger for central heating in which water to be heated passes through a circular array of parallel tubes. Hot gas passes over the outside of the tubes and heats the water up. Metal wire interlaces the tubes and helps conduction heat from the gas to the water. Preferably the arrangement of tubes and wires is metal coated to further help the heat conduction.

Abstract: A vibratory atomizer for atomizing a liquid, the horn and piezoelectric crystal being housed in a housing but separated from the housing by a rubber O-ring so that energy loss to the housing is minimized.

Abstract: A fuel injection nozzle arrangement comprising a fuel injection nozzle having a fuel injection orifice, and vibratory means such as a piezoelectric crystal for vibrating the nozzle to cause atomization of fuel ejected from the nozzle through the orifice, the nozzle having a fuel-retaining valve at the fuel inlet side of the orifice arranged to normally close the orifice and thus prevent the injection of fuel but to be opened when the vibratory means is energised to permit injection of fuel, and the nozzle having a gas-excluding valve at the fuel outlet side of the orifice arranged to normally close the orifice and thus prevent the entry of gases into the nozzle through the orifice but to open under fuel injection pressure to permit the injection of fuel.

Abstract: A vibratory fuel atomizer in which a small housing is located within the atomizer near the atomizer tip, the housing containing a ball valve for shutting off the flow of fuel and a spring for biasing the ball valve to the closed position.

Abstract: A method of measuring the distance per amount of fuel that is being consumed by an engine of a vehicle at any one instant, which method comprises measuring the fuel flow rate to the engine of the vehicle, measuring the vehicle speed, and dividing the vehicle speed by the vehicle fuel flow rate, the method being such that the fuel for the engine is injected through a fuel injection nozzle which is opened for fuel injection by providing the injection nozzle with electrical pulses during periods in which the fuel is to be fed to the engine, and the method also being such that the fuel flow rate is measured by measuring and multiplying together the time that the injection nozzle is open for fuel injection and the repetition time of the pulses.