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:
Mar. 31, 1992
Filed:
Dec. 26, 1990
Christopher A Ludden, Fairport, NY (US);
Clay A Dunsmore, Batavia, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A DC-to-DC converter is operated in accordance with a predetermined primary circuit ON time and a sensed predetermined secondary circuit current level to provide improved charging performance and extended battery life. Energy is stored in the primary of a coupled inductor when power in the primary, provided by a battery having an internal impedance which varies over the battery's lifetime, is switched ON for a predetermined time t.sub.ON. Upon expiration of time t.sub.ON, power is switched OFF, whereupon stored energy is transferred to the secondary via a flyback type process, thus charging a storage capacitor. A preventing means prevents a premature switching ON of power in the primary subsequent to the expiration of time t.sub.ON. The energy storage cycle repeats when current sensed in the secondary decreases below a predetermined minimum current threshold.