摘要:
A method of controlling a motion of an armature away from an electromagnet of an electromagnetic actuator includes the following steps: passing an electric current through a solenoid of the electromagnet for holding the armature at the electromagnet against a resetting force; interrupting the current flow through the solenoid at a desired moment for releasing the armature from the electromagnet; and impressing a current pulse of reverse polarity on the solenoid after interrupting the current flow for launching the armature from the electromagnet.
摘要:
A method for controlling an electromagnetic actuator for a cylinder valve in a piston-type internal combustion engine with the actuator being operatively connected to the cylinder valve and moveable back and forth between two electromagnetics, counter to the force of at least one restoring spring. The current supplied to the electromagnetics is controlled with the aid of a sensor arrangement and via an engine control unit such that the current supply to the catching electromagnet, i.e., the electromagnet being approached by the moveable armature of the actuator, is controlled so as to move the armature slowly toward the respective pole face. Moreover, in order to regulate the valve play during the closing movement of a cylinder valve, the current supply to the catching electromagnet is controlled such that the valve initially touches down softly on its seat and that following the valve play, the armature touches down softly on the pole face.
摘要:
A method of controlling a supply current applied to an electromagnet of an electromagnetic actuator by a control unit for obtaining a low impact speed of a reciprocating armature of the actuator upon arrival of the armature at a pole face of the electromagnet, includes the following steps: during travel of the armature toward the pole face detecting displacements of the armature and a sequence of the armature speed as actual values; comparing the actual values with a performance characteristic field stored in the control unit and relating to a predetermined relationship between armature speed and armature displacement for the armature travel toward the pole face; determining a desired value for the supply current from the comparison step; comparing an actual value for the supply current with the determined desired value; adjusting the supply current based on a difference between the actual and desired values; and applying the adjusted supply current to the electromagnet.
摘要:
A method for recognizing misfires in a piston-type internal-combustion engine with spark ignition and an engine control unit (ECU) for actuating electromagnetic actuators to operate the cylinder valves. The time difference between the opening time preset by the engine control unit and the actual opening time of an exhaust valve is detected as the actual value, then compared to a preset tolerance-time difference as the nominal value, and a signal is generated if this nominal value is not met, i.e., the nominal value exceeds the actual value.