Patent · US Expired

Motion and direction sensors

US5376925A · kind A · utility

17Cited by
7References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 21, 1992
Grant dateDec 27, 1994
Priority date
Expiry dateOct 21, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D3/024
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

Motion and direction sensors for end of train (EOT) telemetry equipment employ a piezoelectric film as the sensing element. The motion sensor has a mechanical design which is optimized for detecting vibration on a railroad car. The electrical circuitry of the motion sensor generates output pulses to the EOT microprocessor which are processed according to an algorithm to make a determination of train motion based on detected vibration levels and rates of occurrence. Also, the EOT microprocessor dynamically adjusts the sensitivity of the motion sensor as a function of detected motion. The direction sensor uses a pendulum aligned with the axis of train motion to stress the piezoelectric film and, like the motion sensor, generates output pulses to the EOT microprocessor. These pulses are processed by a direction sensing algorithm implemented on the EOT microprocessor to determine the direction of train motion.

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