Abstract:
A method is provided for determining the velocity of a pintle assembly in a solenoid fuel injector during a closing stroke of the pintle assembly, such that a braking step is performed during the closing stroke, which includes operating an injector driver with a current regulator to establish a braking current in the solenoid coil. The velocity of the pintle assembly is derived from the duty-cycle of the current regulator during the braking step. A method of operating a solenoid fuel injector, in particular for gaseous fuel, using the so-determined pintle velocity is also provided.
Abstract:
A high pressure fuel pump for use with a direct injection engine having a housing which defines a pump chamber. A port is formed in the housing which fluidly connects a fuel in the passageway with the pump chamber. An elongated valve is movably mounted within the housing between an open and a closed position. In its open position, the inlet passageway is fluidly connected with the pump chamber while, conversely, in the closed position the fuel valve blocks the fluid flow between the inlet passageway and the pump chamber. A circuit controls the deceleration of the valve to reduce pump noise.
Abstract:
In an electromagnetically controlled inlet valve actuator provided to a high pressure fuel pump, an impinging sound which is generated at the time of operating the mechanism is reduced. In a high pressure fuel pump provided with an electromagnetically controlled inlet valve (operated by way of a plunger rod), a current supply period includes a 1st current supply period for performing an operation of attracting the plunger rod in a valve closing direction, a 2nd current supply period for alleviating a speed at which the plunger rod moves in a valve opening direction, and a limited current supply period disposed between the 1st current supply period and the 2nd current supply period in the form of spanning a pump top dead center.
Abstract:
A method for controlling an actuator, such as the type used to drive valves, vanes, and other variable position devices. In one exemplary embodiment, a method may improve the accuracy of actuator feedback by periodically or dynamically resetting the position of a lower hard stop, which can then be used as a future point of reference.
Abstract:
A method for controlling the displacement of a stack of a piezoelectric actuator for use in a fuel injector comprises determining a desired amount of charge (ΔQ) to be added or removed from the stack. The method further comprises determining an operating parameter of the fuel system and selecting a drive current level (PO, SO) and a drive time (topen, tclose) in accordance with the desired amount of charge (ΔQ) and the operating parameter, and driving the drive current through the stack for the drive time (topen, tclose) in order to add or remove the desired amount of charge (ΔQ).
Abstract:
An electromagnetic fuel injection valve device for an internal combustion engine is configured to carry out an energization to an electromagnetic coil of an injection valve actuator for a valve opening motion and additionally carry out a mid-term energization at a time interval between both an energization for valve opening of a previous fuel injection and an energization for valve opening of a subsequent fuel injection. A current of the mid-term energization is smaller than a current of the energization for valve opening motion and has the same direction as a direction of the current of the energization for valve opening motion.
Abstract:
An electromagnetic fuel injection valve device for an internal combustion engine is configured to carry out an energization to an electromagnetic coil of an injection valve actuator for a valve opening motion and additionally carry out a mid-term energization at a time interval between both an energization for valve opening of a previous fuel injection and an energization for valve opening of a subsequent fuel injection. A current of the mid-term energization is smaller than a current of the energization for valve opening motion and has the same direction as a direction of the current of the energization for valve opening motion.
Abstract:
Disclosed is an electromagnetic switching device including a number of fixed contact pieces, a solenoid-operated mechanism, a contact support which can be moved counter to restoring devices in at least one embodiment, with the aid of the solenoid-operated mechanism and on which a number of movable contact pieces are arranged, and an off stop for the contact support. A sensor is provided, in at least one embodiment, for detecting the position of the contact support while a control unit is provided which is connected to the sensor and regulates and/or controls the solenoid-operated mechanism during a switch-off process in order to decelerate the contact support before the same hits the off stop. Also disclosed is a method for operating such a switching device. The contact support, in at least one embodiment, transmits only a small momentum to the off stop, thus reducing the load applied to the involved parts. Such a switching device therefore has a longer service life than conventional switching devices.
Abstract:
In a current supply circuit for starters, an inductance coil is connected in series or a capacitor is connected in parallel with a starter motor to slow down the rise of a current supplied to the starter motor. The current, which flows in a magnet switch upon occurrence of bouncing of the magnet switch, is lowered. Thus even if the time of occurrence of bouncing delays due to increased inductance of a pull-in coil, the magnet switch turns on and off a small current by bouncing and hence generation of noise arising from bouncing can be suppressed. Generation of arc in the magnet switch due to bouncing can be suppressed, and the reliability of the magnet switch can be increased.
Abstract:
A directly actuated injection valve comprises a hollow valve housing, a valve needle disposed within the hollow interior, a needle spring and a tubular magnetostrictive actuator assembly disposed in an annular space around a portion of the valve needle. A magnetic field activates the magnetostrictive material to change its length to cause a corresponding movement of the valve needle that actuates the valve. The valve needle is formed from a ferromagnetic material and extends through the tubular magnetostrictive actuator assembly without interfering with the flux field that is directed through the magnetostrictive member. A passive hydraulic link assembly is preferably employed to compensate for component wear, temperature effects and manufacturing variations within design tolerances.