Abstract:
The invention relates to a method and a device for offsetting bounce effects in a piezo-actuated injection system of an internal combustion engine using a control valve actuated by a piezoelectric actuator. The inventive method comprises the following steps: detecting an actual bounce behavior of the control valve, and determining and offsetting a deviation between the actual bounce behavior and a desired bounce behavior of the control valve, thereby generating an actuation information for the control valve which influences a speed characteristic of a needle of the control valve. The invention also relates to a device for carrying out the inventive method.
Abstract:
The present invention relates to a method and an apparatus for controlling a high-pressure fuel supply pump configured to supply pressurized fuel to an internal combustion engine, with a solenoid-actuated intake valve being configured to be biased into a first direction towards a first stop position of the intake valve by means of a biasing force and being configured to be displaced against the biasing force into a second direction opposite to the first direction towards a second stop position of the intake valve by means of magnetic force and to be kept at the second stop position by means of magnetic force. The method includes applying control current to the solenoid-actuated intake valve for displacing the intake valve into the second direction to the second stop position and for keeping the intake valve at the second stop position during a first time period by means of magnetic force.
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:
A method of displacing a pumping assembly. In a first step, a first current is applied in a first direction through a coil assembly to displace a drive assembly from an initial position to cause a first pumping motion. Then, the drive assembly is returned to the initial position to cause a second pumping motion. At some point nearing the end of the second pumping motion, a second current is applied in the first direction through the coil assembly to decelerate the drive assembly before it reaches the initial position. A third current may be applied in a second direction through the coil assembly to cause or assist a return of the drive assembly to the initial position. An apparatus capable of carrying out the method is also disclosed.
Abstract:
A method and system controls motion of an armature 112 of a fuel injector 100. The armature moves between an open coil 118 and a close coil 116 of the injector. Acceleration current of a certain polarity is applied to the open coil 118 with the armature disposed at the close coil 116. De-latching current of a polarity opposite of the certain polarity is applied to the close coil 116 to release magnetic latch on the armature thereby accelerating movement of the armature towards the open coil 118. Deceleration current is applied the close coil 116 thereby decelerating the armature prior to reaching the open coil. Latching current of the certain polarity is applied to the open coil 118 prior to or just after impact of the armature 112 with the open coil 118 to magnetically latch the armature to the open coil 118 thereby reducing bounce of the armature at impact.
Abstract:
A method for controlling a solenoid valve, particularly in a motor vehicle. The inventive method is characterized by applying a first voltage (U—1) to a coil (21) of the solenoid valve (22) until a first point in time (t—1) and then applying a second voltage (U—2) with a smaller value. The first point in time t—1 precedes the point in time at which the solenoid valve (22) reaches its final position.
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:
A directly actuated injection valve comprises a hollow valve housing, a valve member disposed within the hollow interior, a biasing mechanism, an actuator assembly and a passive hydraulic link assembly. The valve member is movable between a closed position and an open position for governing the flow of fuel into the combustion chamber of an internal combustion engine. The biasing mechanism, preferably a spring, biases the valve member in the closed position. The actuator assembly generates an opening force that acts against the valve spring to open the valve. The hydraulic link assembly is interposed between the valve member and the valve spring and the actuator assembly. The hydraulic link assembly transmits respective closing and opening forces to the valve member. The hydraulic link preferably comprises a piston disposed within a cylinder that is filled with a hydraulic fluid.
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.