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:
Dec. 09, 1986
Filed:
Aug. 17, 1984
Martin A Afromowitz, Seattle, WA (US);
Innovation Associates, Bellevue, WA (US);
Abstract
An inclinometer, adapted to be rigidly secured to an object, for detecting the amount and direction of the inclination of the object in any direction with respect to a horizontal or other reference plane. The inclinometer comprises a fiber optic rod rigidly mounted at one of its ends and having a weight secured to its free end. The free end of the rod has two degrees of freedom of motion with respect to its rigidly mounted end. Light is supplied to the rod's mounted end and light emitted from the rod's free end falls on a continuous two dimensional optical detection surface area of an optical detector which uniquely detects the position of the spot of light falling anywhere on its surface area, regardless of the direction in which the spot of light moves on its surface area. From the position of the spot of light on the surface area, the amount and direction of inclination of the object can be determined. Undesired oscillations of the free end of the optical fiber rod, caused by acceleration of the inclinometer, are reduced by surrounding the rod and/or weight with a viscous liquid, and/or by also providing fins on the weight to increase its fluid resistance. A temperature sensor allows for correction of the inclination angle detected caused by changes in temperature of the inclinometer. A pure fused silica optical fiber rod is preferred, to prevent undesired hysteresis which might otherwise be caused by an elastic deformation of the optical fiber rod.