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:
May. 13, 1997
Filed:
Jul. 11, 1995
Steven A Scampini, Bedford, MA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A protective circuit controls electronic equipment in the presence of a high level electro-magnetic field. The protective circuit includes a field sensor arrangement which provides output signals that are indicative of magnetic field strength components that are aligned along desired spatial axes. A vector converter circuit is connected to the field sensors and provides an output having a magnitude that is indicative of the vector sum of the electro-magnetic field strength components. A first indicator is responsive to an output from the vector converter reaching a first threshold to manifest a caution signal that the magnetic field strength has reached a cautionary level. A second indicator is responsive to an output from the vector converter reaching a second threshold that is higher than the first threshold, to disable the electronic equipment. Further circuitry is provided to re-enable the electronic equipment if it is moved outside of the area where the magnetic field exceeds the first threshold.