Patent · US Expired

Fiberoptic microbend accelerometer

US4930862A · kind A · utility

20Cited by
4References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 1989
Grant dateJun 5, 1990
Priority date
Expiry dateApr 19, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P15/093
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An accelerometer comprises a base and cover together defining a chamber which receives an inertial mass. The diaphragm carries the inertial mass and is bolted between the base and the cover. The inertial mass and the base have facing incorrugated surfaces with offset teeth in each of the corrugated surfaces. An optical fiber is clamped between the teeth and extends between the corrugated surfaces. The intensity of light passing through the fiber changes with movement of the inertial mass with respect to the base. The inertial mass moves through the resiliency of the diaphragm, when the base is subjected to accelerations, such as those caused by vibrations. A reference optical fiber may also extend through the chamber above the inertial mass. The same light is supplied to both fibers and the intensity of light from both fibers is subtracted to leave the variation in intensity due to bending of the sensing optical fiber. Also, an electronics circuit employing a log-ratio amplifier device measures the light signals from the optical fibers and converts them to electrical signals which are proportional to the acceleration measured with the foregoing accelerometer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.