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. 17, 1990
Filed:
Dec. 12, 1988
Donald L Cummins, Anderson, IN (US);
Stephen P Santichen, Anderson, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An electric starting system for controlling an electric starter that has a solenoid for shifting a pinion and for closing solenoid contacts to energize a cranking motor that drives the pinion. The solenoid has a single coil connected in series with a plurality of parallel connected field effect transistors. The circuit that energizes the solenoid coil through the field effect transistors is in parallel with the solenoid contacts and the cranking motor. The gates of the transistors are connected to an oscillator which causes the transistors to be repeatedly turned on and off at a predetermined frequency and duty cycle. Pulses of current are supplied to the solenoid coil which are sufficient to maintain the pinion meshed with the ring gear of an engine and to maintain said solenoid contacts closed without overheating the coil.