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:
Dec. 29, 1987
Filed:
Sep. 02, 1986
Rudolph H Engelmann, Ann Arbor, MI (US);
Electro-Voice Inc., Buchanan, MI (US);
Abstract
A battery charging system including a plurality of transformers each having a primary winding, a secondary winding, and a tertiary windings, the primary windings being connected in series forming a 'shared primary', a first switching network for connecting a DC voltage across the shared primary winding, in alternating polarity over successive half-cycles of a clock signal, for causing voltage pulses to be induced into the secondary and tertiary windings of the transformers, a second switching network responsive to the magnitude of primary current for shorting the same or different combinations of the tertiary windings, thereby shorting the associated transformers, over each half-cycle of a clock signal, for controlling the magnitude of charging current to the batteries, and a plurality of rectifiers for rectifying the AC voltages developed in each secondary winding, respectively, for providing charging current to the battery.