Patent · US Expired

Recorder of the status of a traffic control system

US4383240A · kind A · utility

15Cited by
4References
30Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 24, 1981
Grant dateMay 10, 1983
Priority date
Expiry dateFeb 24, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08G1/097
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A recorder of the states of a traffic control system which stores and visually displays the current operational state of the system. The current states of the command signals produced by the traffic controller of the system and the current states of energization of each traffic signal light, after a predetermined delay, are stored in a bistable device. The occurrence of an error, conflicting or improper timing of the energization of the traffic lights of the system or of the command signals controlling the energization of such lights are sensed by a conflict monitor. Upon the occurrence of an error, the bistable devices are latched, i.e. prevented from thereafter changing state. The state of each bistable device is visually displayed as of the occurrence of an error.

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