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:
Apr. 29, 1980
Filed:
Mar. 06, 1978
David T Cavil, Menomonee Falls, WI (US);
William R Krueger, Hartford, WI (US);
Outboard Marine Corporation, Waukegan, IL (US);
Abstract
Disclosed herein is an engine ignition system comprising a charge capacitor, first and second ignition coils respectively including first and second primary windings and first and second secondary windings connected respectively to first and second spark plugs, first and second electronic switches respectively including first and second anodes connected respectively to first and second primary windings, first and second cathodes connected to the charge capacitor, and first and second control elements operable, upon application thereto of a trigger current pulse, to cause the first and second switches to be conductive, and which employs rotary pulse generator means including a relatively rotatable magnet and trigger coil for generating trigger voltage pulses in response to engine rotation, the trigger coil having first and second ends respectively connected to the first and second control elements, a first diode having a cathode connected to and between the first end of the trigger coil and the first control element and having an anode, and a second diode having a cathode connected to and between the second end of the trigger coil and the control element, and having an anode, and active pulse discriminating means for preventing false triggering of the switches, and comprising an active filter circuit including a blocking capacitor having a first plate connected to the first and second cathodes and having a second plate, a resistor having a first end connected to the first and second cathodes and having a second end, the blocking capacitor developing a blocking voltage when a trigger voltage pulse is applied to the first plate, the filter circuit also including current control means having a first terminal connected to the first and second cathodes and the first plate of the capacitor and to the first end of the resistor, a second terminal connected to the second plate of the capacitor and to the second end of the resistor, and a third terminal connected to and between the anodes of the first and second diodes, the current control means being rendered conductive so that a trigger current pulse sufficient to render one of the switches conductive flows between the first and third terminals and through the trigger coil when a trigger voltage pulse exceeds the blocking voltage and a control current is applied to the second terminal.