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:
Feb. 26, 1980
Filed:
Dec. 29, 1978
John L Plumb, Danvers, MA (US);
Sheppard Cohen, Danvers, MA (US);
Paul H Ingalls, Swampscott, MA (US);
GTE Sylvania Incorporated, Stamford, CT (US);
Abstract
An isolator circuit for use with a switching circuit for energizing a ballasted load in response to a control signal of preselected frequency superimposed on AC power circuits which supply the load. In the switching circuit, a triac is gated to conduct the AC power to the load by a circuit including an impedance element and a series resonant LC network tuned to the frequency of the control signal. The control signal may be one of a plurality of control signals having different frequencies superimposed on the power circuits. The isolator circuit is connected between the traic and the load and comprises a plurality of series connected parallel resonant LC circuits each tuned to block a respective one of the control signals. A series choke blocks spurious signal voltages.