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. 06, 2007
Filed:
Apr. 27, 2004
J. David Egner, Sammamish, WA (US);
J. David Egner, Sammamish, WA (US);
Microsoft Corporation, Redmond, WA (US);
Abstract
An appliance leakage current interrupter (ALCI) includes components for preventing sustained over-voltage and sustained over-current conditions. A current interruption threshold is inversely proportional to voltage supplied to the appliance. A microprocessor measures the voltage level of the incoming AC mains supply. The microprocessor is coupled to a sub-circuit for intentionally inducing a current mismatch between the two power lines monitored by the ALCI. Upon detecting an over-voltage of sufficient magnitude and duration, the microprocessor induces a current mismatch in the power lines, thereby causing the ALCI to interrupt power. A second current sensing transformer monitors one of the power lines. The microprocessor also receives the output of the second current sensing transformer. Upon detecting a current level exceeding a variable threshold, the microprocessor induces a current mismatch in the power lines and causes the ALCI to interrupt power.