Piezoelectric injector and method for controlling the same
AssigneesHyundai Motor Company, Kia Motors Corporation
InventorHyeon Jin Lee
Life of this patent
Estimating the term…
Abstract
A piezoelectric injector includes: a first piezo actuator and a second piezo actuator; a control valve connected to the first piezo actuator and the second piezo actuator through a control piston; at least one drain chamber in which the control valve and the control piston are movably received; a control chamber connected to the drain chamber through a first drain throttle and a second drain throttle having different diameters; and a needle movable by a change in fuel pressure of the control chamber to open and close at least one nozzle orifice. As at least one of the first piezo actuator and the second piezo actuator expands, a fuel is drained from the control chamber to the drain chamber through at least one of the first drain throttle and the second drain throttle.
Claims17
A piezoelectric injector, comprising:
- an injector body having a high-pressure fuel passage;
- a nozzle provided in a lower end portion of the injector body, and having at least one nozzle orifice;
- a first piezo actuator and a second piezo actuator disposed inside the injector body;
- a control valve connected to the first piezo actuator and the second piezo actuator through a control piston;
- at least one drain chamber in which the control valve and the control piston are movably received;
- a control chamber connected to the drain chamber through a first drain throttle and a second drain throttle;
- and
- a needle movable by a change in fuel pressure of the control chamber to open and close the nozzle orifice,
- wherein a fuel is drained from the control chamber to the drain chamber through at least one of the first drain throttle and the second drain throttle as at least one of the first piezo actuator and the second piezo actuator expands.
A method for controlling a piezoelectric injector, the piezoelectric injector comprising:
- a first piezo actuator and a second piezo actuator;
- a control valve which is connected to the first piezo actuator and the second piezo actuator through a control piston;
- at least one drain chamber in which the control valve and the control piston are movably received;
- a control chamber which is connected to the drain chamber through a first drain throttle and a second drain throttle having different diameters;
- a needle which is movable by a change in fuel pressure of the control chamber to open and close at least one nozzle orifice;
- and a controller controlling the first piezo actuator and the second piezo actuator, wherein a fuel is drained from the control chamber to the drain chamber through at least one of the first drain throttle and the second drain throttle as at least one of the first piezo actuator and the second piezo actuator expands, the method comprising:
- applying, by the controller, a current to at least one of the first piezo actuator and the second piezo actuator so that at least one of the first piezo actuator and the second piezo actuator expands.
Dependencies are inferred from the claim text.