Diesel injection nozzle with independent opening and closing control

Abstract From the Canadian patent

A fuel injector for a diesel engine for use with a common rail type universal fuel injection system includes an injection piston driven by the common rail pressure fluid to inject a metered quantity of fuel through an injection nozzle. The opening of the nozzle valve is controlled by a compression spring in a conventional manner. The nozzle closing is effected by the introduction of fuel at injection pressure above the nozzle valve which acts in combination with the spring to seat the valve. In the preferred embodiment means, are provided for connecting the nozzle spring chamber with the pumping chamber of the injection piston at or slightly before the end of delivery of injected fuel to …