151results about "Fuel injection with piezoelectric/magnetostrictive elements" patented technology

The invention relates to a fuel injector for use in an internal combustion engine, comprising a nozzle body (40) being provided with a nozzle bore (66) and at least one set of one or more outlets for fluid, an outer valve member (68) received within the nozzle bore (66) and being engageable with a first seating region (100a) of the nozzle body (40) to control the flow of a first fluid from a first delivery chamber (98), the outer valve member (68) being provided with an outer valve bore (74), and an inner valve member (76) received within the outer valve bore (74) and being engageable with a second seating region (100b) of the nozzle body (40) to control the flow of a second fluid from a second delivery chamber (142). In various embodiments, the fuel injector can be arranged to allow the first and second fluids to be injected separately and / or together. In one embodiment, the first and second fluids can be mixed within the injector before injection.

There is disclose a high-pressure fuel pump and a fuel injection valve connected to it for each cylinder of an internal combustion engine. A pump piston of the pump delimits a working chamber connected to a pressure chamber of the injection valve having a valve element controlling injection openings and movable in an opening direction counter to closing force by pressure prevailing in the pressure chamber. A control valve controls connection of a control pressure chamber with the pump-working chamber delimited by a control piston to a relief chamber. When the injection valve element is closed, the control piston opens a main connection with a large flow cross section and when the injection valve element is open, this control piston closes the main connection, only opening a bypass connection with small flow cross section, the bypass connection is embodied in a housing part delimiting the control pressure chamber.

A method of identifying an individual short circuit fuel injector, within an injector bank of an engine comprising a plurality of fuel injectors. Each fuel injector has a piezoelectric actuator and an associated injector select switch forming part of an injector drive circuit. The method comprises: (i) charging all of the piezoelectric actuators of the plurality of fuel injectors within the injector bank during a charge phase; (ii) at the end of the charge phase waiting for a delay period; and (iii) subsequently closing an injector select switch of a fuel injector to select said fuel injector. The method further comprises: (iv) determining a stack voltage present on terminals of the piezoelectric actuator of the selected fuel injector and storing the stack voltage in a data store. The stack voltage is indicative of an amount of charge present on the selected injector at the end of the delay period. The method further comprises (v) repeating steps (i) to (iv) for each fuel injector in the injector bank in turn; and (vi) identifying the individual short circuit fuel injector as being the injector which has discharged beyond a predetermined voltage drop limit during the delay period. The method also comprises generating a short circuit fault signal for the identified fuel injector.

A supplying unit supplies energy to an actuator so that the supplied energy is kept therein, making displacement the actuator. An interrupting unit interrupts the supply of energy to cause the actuator to discharge the kept energy, making displacement the actuator. A converting unit is adapted to convert the displacement of the actuator corresponding to the kept energy into hydraulic pressure applied to the valve member, moving the valve member to open the low pressure port and close the high pressure port. The convert unit converts the displacement of the actuator corresponding to the discharged energy into hydraulic pressure applied to the valve member, moving the valve member to open the high pressure port and close the low pressure port. Energy which the actuator requires to move the valve member so as to close the high pressure port is larger than energy which the actuator requires to move the valve member so as to open the low pressure port.