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. 02, 1995
Filed:
Oct. 15, 1992
Arthur Dumais, Rochester, MI (US);
Richard D Koski, Troy, MI (US);
Patriot Sensors and Controls, Clawson, MI (US);
Abstract
The present application discloses a magnetostrictive linear displacement detector with an axial coil torsional strain transducer. The displacement detector includes a magnetostrictive wire, a return wire and a magnet disposed for displacement along the magnetostrictive wire. A torsional strain sensor at the head end generates an electrical indication of the torsional strain within the magnetostrictive wire induced by passage of an electrical excitation by the position of the magnet. The torsional strain sensor includes two serially connected coils wound in opposite directions. The total length is short compared with the rate of electrical propagation within the magnetostrictive wire and long compared with the rate of torsional strain propagation within the magnetostrictive wire. The induced current within the two coils from electrical excitation of the magnetostrictive wire substantially cancel out because generally the whole sensor is excited simultaneously. The torsional magnetic disturbance accompanying the propagating strain, which is of a much narrower extent, generally induces current in only one of the two sections at a time. This transducer is advantageous because the response in not critically dependant on location.