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:
Nov. 10, 1998
Filed:
Apr. 28, 1997
Terje Kvisteroy, Horten, NO;
Henrik Jakobsen, Horten, NO;
SensoNor asa, Horten, NO;
Abstract
A force sensor device for sensing seismic force due to changes in acceleration or pressure, comprising mass-spring system formed by a resonant flexible plate forming system mass and suspended from a rigid frame by means of at least two beams forming system springs and located at different sides of the plate, the plate, frame and beams being made of a silicon. A vibration excitation device upon application of electric signals at an elected one of a plurality of specific frequencies interacts with the plate to create a corresponding specific vibration mode therein, and a detection device detects any vibration frequency change in the plate due to interaction between a stress field thereon caused by the seismic force and a stress field thereon caused by the vibration mode.