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. 05, 1986
Filed:
Jul. 16, 1985
Mark R Pflederer, Tremont, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A fuel injection solenoid driver circuit controllably connects and disconnects a solenoid coil to and from a storage capacitor to effect operation of the coil. Precise control of the timing and duration of coil is necessary to ensure that a proper quantity of fuel is delivered to each cylinder of an internal combustion engine. A means monitors the voltage level of the storage capacitor and periodically delivers a high voltage inductive spike to the capacitor to maintain the capacitor voltage level within prescribed limitations. Further, a means aids in charging the capacitor by discharging the solenoid coil to the capacitor in response to the coil and capacitor being disconnected. Use of the energy stored in the coil to recharge the capacitor increases the power efficiency of the circuit and also results in a fast decay of the solenoid voltage. The fast decay time minimizes variations in solenoid operation timing and duration and precisely controls the quantity of fuel delivered.