Stanadyne Corporation

Mark S Cavanagh

Robert G Lucas

Yevgeniy Norkin

A needle type fuel injector has a needle control chamber at a pressure subject to a control valve in a control valve chamber which in an opening phase is lifted from its seat to expose the control valve chamber, connecting passage, and needle control chamber to a low pressure drain and in a closing phase is urged against the seat to isolate the control valve chamber, connecting passage, and needle control chamber from the drain. The potential for cavitation at high fuel injection pressure is reduced by throttling the flow of fuel past the control valve seat when the control valve opens, thereby maintaining sufficient back pressure in the control valve chamber and upstream connecting passages.

Method of suppressing cavitation in a fuel injector

A tubular debris shield and diverter mounted in a high pressure flow passage within a fuel injector, provide the dual functions of passing the main flow of high pressure fuel with large debris particles to relatively large discharge openings, such as the injector spray holes, while allowing some high pressure fuel to flow through a multitude of very small transverse holes to a sensitive hydraulic component, such an injector control valve circuit. In one embodiment, the tube has a wall thickness in the range of about 0.1 to 0.5 mm at least about 2000 holes with a diameter in the range of about 20 to 30 microns.

Debris diverter shield for fuel injector

An atomizing injector comprises a body having a central bore with a valve situated in the bore, leading to a chamber. An actuator moves the valve between closed condition and open conditions, selectively exposing the chamber to a flow of pressurized liquid. A discharge port extends from the chamber to a discharge orifice. A swirl element is situated in the chamber, while leaving a free space in the chamber immediately above the discharge port. When the valve is opened, liquid flows into the chamber, through the swirl element into the space, forming a whirl in the space before passing through the discharge port and exiting the discharge orifice as an atomized whirling spray.

Injector having swirl structure downstream of valve seat

Anti-cavitation throttle for injector control valve

A needle type fuel injector has a needle control chamber at a pressure subject to a control valve in a control valve chamber which in an opening phase is lifted from its seat to expose the control valve chamber, connecting passages, and needle control chamber to a low pressure drain and in a closing phase is urged against the seat to isolate the control valve chamber, connecting passages, and needle control chamber from the drain. Resistance to the flow or displacement of fuel through the control valve seat is provided by a pressure regulating valve as the control valve rapidly closes against its seat, thereby reducing the rate of closure and thus the impact of the control valve on the seat.

Common rail injector with regulated pressure chamber

A urea solution injection system and an injector with which urea solution or other exhaust treatment liquid from a source tank can be injected as an atomized spray into an exhaust pipe. A metering pump with integrated injection nozzle are contained in a common housing mounted directly to the exhaust pipe, thereby eliminating the separate electric motor driven pump, line between pump, and injector in conventional systems.

Growing community of inventors

West Granby, CT, United States of America

Mark S Cavanagh