摘要:
An actuator module including a piezoactuator, for example for a piezoinjector for metering fuel in an internal combustion engine, is proposed. The piezoactuator has piezoelements stacked one above another between an actuator head and an actuator foot and is provided with at least one elastomer layer enclosing the piezoelements. The elastomer layer is enveloped by a corrugated bellows or by telescopic tubes, composed of a material that is diffusion-impermeable with respect to a fuel to be metered by the piezoinjector. The corrugated bellows or the telescopic tubes have on their periphery grooves which can absorb expansions of the elastomer layer or of the piezoactuator.
摘要:
The invention relates to a piezoelectric actuator used as a piezoelectric injector, comprising a holding body provided with an inner region, an upper part and a lower part, and a piezoelectric element which is arranged in the inner region against the upper part of the holding body and includes a plurality of piezoelectric layers arranged in the form of a stack, The piezoelectric element can be electrically contacted through the holding body. The upper part of the holding body has at least one connection for electrically contacting the piezoelectric element, and at least one connection and flow channels for feeding the inner chamber with a fluid that can be metered by means of a regulating element containing the piezoelectric element. An electrical plug-in connection is arranged between the piezoelectric element and the upper part of the holding body, which includes a mechanical plug-in connection being arranged between the holding body upper part and the piezoelectric element.
摘要:
The invention relates to a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, which system has an injector housing (1) with a fuel inlet (24) that is in communication with a central high-pressure fuel reservoir outside the injector housing (1) and with a pressure chamber (27) inside the injector housing (1), from which fuel subjected to high pressure is injected as a function of the position of a control valve (18) that assures that a nozzle needle (8), which is movable back and forth and received in a longitudinal bore (6) of the injector axially counter to the prestressing force of a nozzle spring (21) that is received in a nozzle spring chamber (20), lifts from a seat when the pressure in the pressure chamber (27) is greater than the pressure in a control chamber (30) that communicates with the fuel inlet (24) via an inlet throttle (19). To achieve markedly higher nozzle needle speeds, the control chamber (15) is formed by a cylindrical chamber, in which a control peg (12), embodied on the end of the nozzle needle (8) remote from the combustion chamber, is displaceable causing a sealing effect, and that the nozzle spring chamber (20) is disposed outside the control chamber (15), in the region of the end of the nozzle needle (8) remote from the combustion chamber.
摘要:
The present invention relates to a leak fuel connection, in particular for a common rail system or a common rail injector, for connecting a leak fuel line via a connecting conduit to a connection end piece. The leak fuel connection, on the outer circumference of a component on which the leak fuel connection is provided, has an at least intermittently annularly embodied conduit, into which the connecting conduit for connecting to the leak fuel line discharges. The annular conduit is connected to the connection end piece via a connection element.
摘要:
A piezoelectric actuator intended for instance for actuating injection valves in internal combustion engines of motor vehicles is protected against destructive tensile strains in that resilient prestressing elements that subject the piezoelectric body to precompression are provided for the piezoelectric body of the actuator.
摘要:
A valve for controlling liquids which for its actuation is provided with a liquid-filled coupling chamber, which is disposed between an actuator piston of a piezoelectric actuator and a piston that actuates a valve member. To compensate for liquid losses suffered by the coupling chamber, which is briefly at high in each work cycle, the pressure difference that exists during the return stroke of the actuator piston between the coupling chamber and the opposite sides of the actuator piston and of the that actuates the valve member that are remote from the coupling chamber is utilized to achieve refilling in valveless fashion along gaps. The valve is used for use in fuel injection systems for internal combustion engines of motor vehicles.
摘要:
A fuel injection system for internal combustion engines is proposed which supplies fuel injection valves with fuel from a high-pressure fuel source, under the control of a control unit. The fuel injection valve has an injection valve member, whose opening or closing position is determined by a pressure that acts upon this injection valve member and that is set in a control chamber. To that end, to perform an injection, the pressure in the control chamber must be relieved; which is achieved with a control valve that opens two different outflow cross sections of an outflow conduit of the control chamber in succession. This makes it possible to accomplish an adapted opening of the fuel injection valve member for a preinjection and for a main injection.
摘要:
A piezoelectric actuator with piezoelectric elements, fastened between an actuator head and an actuator foot, and with a plastic sleeve surrounding at least the piezoelectric elements is proposed, which is set in a clamping ring on the actuator head and/or the actuator foot of the piezoelectric actuator. The respective clamping ring may be a metal part or a plastic part, which is equipped with clamping lugs suitable for setting the plastic sleeve and is thrust, pressed, or shrunk onto the respective actuator head and/or actuator foot of the steel piezoelectric actuator.
摘要:
An actuator unit suitable for actuating a fuel injection valve of an injection system for internal combustion engines is comprised of a piezoelectric actuator and a hollow body embodied in the form of a spring. Embodying the hollow body according to the present invention can extend the service life of the actuator unit.
摘要:
A piezoelectric actuator module has at least one piezoelectric element, one actuator foot and one actuator head, and is surrounded by an axially extending sleeve. To seal off the piezoelectric actuator module in the axial direction, the actuator foot is adjoined by a diaphragm that extends essentially in the radial direction and is connected to the sleeve.