Error detecting circuit for a traffic control system
US4135145A · kind A · utility
19Cited by
7References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 7, 1976 |
| Grant date | Jan 16, 1979 |
| Priority date | — |
| Expiry date | Sep 7, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/097
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An error detecting circuit which senses the operating states of a plurality of traffic signal lights the energization of which is controlled by a single block of load switches and which circuit produces an error signal when certain predetermined relations exist for a predetermined period of time between the states of the lights, such as, if more than one traffic signal light of one traffic signal head is energized simultaneously or if none of the traffic signal lights of one traffic signal head is energized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.