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. 28, 1978
Filed:
Aug. 03, 1976
Charles R Wesner, Crozet, VA (US);
Sperry Rand Corporation, New York, NY (US);
Abstract
Direct current error signals of either polarity are converted to a unipolar voltage and used to offset a triangular timing wave. The offset wave is applied to threshold amplifier so as to produce pulse width modulated signals. The pulse width modulated signals, together with a polarized direction signal and a clock signal from the triangular wave source, is applied to a servo amplifier containing first and second channels, each containing a flip flop for opening the associated channel in accordance with the polarity of the direction signal so as to pass direct or inverted pulse width modulating signals, respectively, through amplifier and filter circuits to the output terminal. Each of the amplifier circuits has a current sensing resistor, and a switching transistor arranged to switch the associated flip flop and thereby open that channel whenever the current through the sensing resistor exceeds a predetermined level.