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:
Nov. 30, 1993
Filed:
May. 04, 1987
Timothy Graff, Palatine, IL (US);
Gregory A Peterson, South Barryington, IL (US);
Digital Appliance Controls, Inc., Hoffman Estates, IL (US);
Abstract
The operation of an electromechanical relay is synchronized with the power line waveform where an electrical power supply is supplied from a source to an electrical load. The current voltage supplied to the load is characterized by a power line waveform. An electromechanical relay is positioned between the power supply and the load where contacts of the relay are opened and closed to interrupt and supply power to the load. A microcontroller is positioned between a power source and the electromechanical relay and actuates the relay so that when the contacts are closed or opened the contacts are not exposed to an undesired voltage. A feedback control circuit senses the opening and closure of the contacts so that in the event the contacts, for example close at an undesireable point on the load current waveform the microcontroller adjusts for the necessary delay to cause the actuation of the relay to occur such that the contact closure is at the desired point in the load current waveform.