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. 25, 1995
Filed:
Oct. 02, 1992
Richard J Backus, Rochester, NY (US);
Lee A Finch, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
An arrangement for controlling a zero crossing switch in order to connect a source of zero crossing AC voltage to and disconnecting it from an AC load line is disclosed herein along with its method of operation. To this end, means are provided for producing externally controlled command signals intended to control when the switch connects and disconnects the load line to and from the AC voltage. At the same time, a specific window of time is selected, which window begins a particular period of time prior to and includes at least certain zero crossing points of the AC voltage. Internally controlled command signals are produced in response to the AC voltage and externally controlled signals for actually controlling when the switch connects (ON) and disconnects (OFF) the load to and from the AC voltage. These internally controlled signals are produced such that either an ON or OFF signal, but not both, is produced entirely throughout the specific window of time in order to prevent command signals from switching between ON and OFF states within any given window of time. This, in turn, reduces current surges at the output of the zero crossing switch, thereby reducing electromagnetic interference (EMI).