The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 10, 1999
Filed:
Jul. 30, 1998
Guenter Schmitz, Aachen, DE;
Franz Pischinger, Aachen, DE;
Abstract
A method of initiating motion of at least one of cylinder valve of a cylinder of a reciprocating engine, with each cylinder valve being actuated by an electromagnetic actuator having an electrical closing magnet and an electrical opening magnet, between which magnets an armature that is connected to the cylinder valve to be actuated is movably guided back and forth, counter to the forces of restoring springs, and with the alternating current supply to the closing magnet and the opening magnet being controlled by an electrical engine control. The natural frequency of the spring-mass system formed by the restoring springs and the armature with the cylinder valve is stored in the electrical engine control. The instantaneous rpm and position of the crankshaft with respect to a dead center point position and with reference to the stored natural frequency are detected by the engine control. The time for the beginning of an alternating current supply to the electromagnets is calculated in the period of the natural frequency, taking into consideration the crankshaft rpm and position, the natural frequency of the spring-mass system and the armature path from an inoperative position until it is in contact with the pole surface of one of the two electromagnets, so that the armature motion and the piston motion occur in the same direction immediately before a possible contact of the armature with the pole surface of a capturing magnet.