Railway control signal dynamic output interlocking systems
US4305556A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 1979 |
| Grant date | Dec 15, 1981 |
| Priority date | — |
| Expiry date | May 23, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/181
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A computer based railway interlocking control system, having triple parallel redundant control computers (FIG. 2) provides greater system reliability as compared to a single computer system. The railway traffic control devices, e.g. points and signals, are arranged to be controlled by signals in one of two possible steady states, the interlocking control means (30, 31, 32, FIG. 2) is arranged to produce control signals in the steady state for de-energized or "safe" device settings and in an alternating state for energized or potentially "unsafe" settings. The alternating control signals (33, 34, 35 or 38) must be converted to the corresponding steady state to operate the devices thus, the converting or restoring circuit discriminates against dormant wrong side failures, i.e. "unsafe" signals to increase the inherent safety of the system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.