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:
Jan. 31, 1984
Filed:
Jun. 21, 1982
James R Jaeschke, Waukesha, WI (US);
Walter L Rutchik, Wauwatosa, WI (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
An AC transistor switch is provided with simple, accurate and fast overcurrent protection circuitry. A pair of transistors are connected in anti-series across an AC load line, and each transistor has an anti-parallel diode therearound conducting current in the alternate half cycles. Comparator means senses current flow through the diodes and is responsive to given threshold overload current to turn off the transistors. Voltage sensing means is referenced to a common point between the series connected transistors and senses the voltage at each main terminal relative to the common point to thus sense the voltage drop from the common point across each diode to its respective main terminal for sensing current flow through the respective diode. The current representative voltage is sensed through respective dedicated third and fourth diodes connected to the main terminals and having a common anode connection to the voltage sensing means such that the latter senses the more negative of the main terminals regardless of the relative potential therebetween.