United States Patent Number: 5,483,214, January 9, 1996.
NOTE: At time of publication, the author Lanny Griffin was not yet affiliated with Cal Poly.
A sensor for use with high-power solenoid-actuated relays, and for detecting and signalling relay armature position and hence the actuation state of the relay. The sensor is external to a sealed chamber in which the relay contacts and armature system are positioned, and includes a permanent magnet, the flux path of which includes the relay armature and base. Armature movement to close the relay alters the flux path to operate a reed switch adjacent the magnet, and the condition of the reed switch signals the unactuated or actuated state of the relay.
Biomedical Engineering and Bioengineering
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