초록 ▼

An improved electronically-controlled fluid injector system comprises a fluid storage chamber and a direct-operated check. Pressurization of fluid in the storage chamber begins before the start of fluid injection. Fluid injection begins by hydraulically unbalancing the check. Fluid injection sharply

An improved electronically-controlled fluid injector system comprises a fluid storage chamber and a direct-operated check. Pressurization of fluid in the storage chamber begins before the start of fluid injection. Fluid injection begins by hydraulically unbalancing the check. Fluid injection sharply ends by hydraulically balancing the check to allow a biasing device to close the check. The present invention provides improved control of several fluid injection parameters, including higher peak fluid injection capability and less fluid injection pressure drop at the end of injection, resulting in improved engine performance and lower emissions, noise, and wear.

대표청구항 ▼

An electronically-controlled unit fluid pump injector comprising: a housing portion defining a fluid control passage and a fluid storage chamber; a first pressure control valve operable to selectively open and close fluid communication between the storage chamber and the control passage; a nozzle po

An electronically-controlled unit fluid pump injector comprising: a housing portion defining a fluid control passage and a fluid storage chamber; a first pressure control valve operable to selectively open and close fluid communication between the storage chamber and the control passage; a nozzle portion defining a pressure control chamber and at least one fluid injection orifice; a fluid pressurization member selectively movable between a first position and a second position, when the first valve is opened said member operable during movement from its first to second positions for displacing fluid from the storage chamber to the control passage, when the first valve is closed said member operable during movement from its first to second positions for displacing fluid in the storage chamber thereby pressurizing such fluid to a selected pressure; a movable direct-operated check operable to selectively close and open fluid communication between the storage chamber and the fluid injection orifice, said check having a first end portion and a second end portion, said first end portion defining a first effective area arranged in partial fluid communication with the storage chamber when the check is closed, said first effective area arranged in complete fluid communication with the storage chamber when the check is opened, said second end portion defining a second effective area arranged in fluid communication with the pressure control chamber; and a second pressure control valve selectively movable between a first position and a second position, said second valve at its first position closing fluid communication between the pressure control chamber and the control passage and opening fluid communication between the pressure control chamber and the storage chamber, said second valve at its second position opening fluid communication between the pressure control chamber and the control passage and closing fluid communication between the pressure control chamber and the storage chamber, when the check is closed and the second valve is at its second position said first and second effective areas are operable for hydraulically opening the check, when the check is opened and the second valve is at its first position said first and second effective areas are operable for balancing opposing hydraulic forces acting on such effective areas.