초록 ▼

A Villari effect sensor comprises a sensing rod constructed from a magnetostrictive material. An alternating current signal applied to an overlapping drive coil is inductively coupled by the sensing rod to the sensing coils and generates a signal thereon, responsive to the permeability of the magnet

A Villari effect sensor comprises a sensing rod constructed from a magnetostrictive material. An alternating current signal applied to an overlapping drive coil is inductively coupled by the sensing rod to the sensing coils and generates a signal thereon, responsive to the permeability of the magnetostrictive sensing rod which decreases responsive to the applied load. The sensing rod comprises one or more sections, each having a distinct cross-sectional area, and a sensing coil is associated with each section. A signal processor calculates the magnitude of the applied force from either the maximum flux density, or by differencing the first and third harmonics of the signal from the sensing coil. The weight of an occupant on a vehicle seat is measured by either incorporating a tensile force measuring Villari effect sensor in series with the seat springs, or incorporating a compressive force measuring Villari effect sensor in series with seat posts.

대표청구항 ▼

[ We claim:] [1.] A Villari effect sensor for measuring an applied force, comprising:(a). a magnetostrictive sensing rod in series with the load path of the applied force, whereby said sensing rod is linear and continuous and further comprises a plurality of sections, each said section adjacent to o

[ We claim:] [1.] A Villari effect sensor for measuring an applied force, comprising:(a). a magnetostrictive sensing rod in series with the load path of the applied force, whereby said sensing rod is linear and continuous and further comprises a plurality of sections, each said section adjacent to one another and having a distinct cross-sectional area;(b). a drive coil concentric with said sensing rod for magnetizing said sensing rod responsive to an alternating current applied to said drive coil;(c). a plurality of sensing coils concentric with said sensing rod, each said sensing coil inductively coupled to said drive coil about one of said plurality of sections of said sensing rod, whereby each said sensing coil generates a signal responsive to the force-dependent permeability of said sensing rod at each one of said plurality of sections; and(d). a signal processor operatively coupled to said plurality of sensing coils for calculating the applied force from said signals generated by each of said plurality of sensing coils.