Inventors
Frank W Murphy Jr, James R Francisco, Charles R Lawrence, Troy Teague
Publication date
1990/12/4
Patent office
US
Patent number
4975687
Application number
07399810
Description
A signalling gauge may utilize a non-captivating, magnetically actuated switch element which is mounted in an influence zone of a path of a magnet carried by an indicating pointer of the gauge. The gauge may operate despite the presence of dust, dirt or other pollutants for an extended period of time without inducing sparks or arcing often associated with electromechanical contacts. Hall effect switch elements such as latches or digital switches may be utilized as a switch element for signalling to drive an audio or visual alarm or a digital signal.
Total citations
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Scholar articles
FW Murphy Jr, JR Francisco, CR Lawrence, T Teague - US Patent 4,975,687, 1990