In-circuit contact monitor

Details In-circuit contact monitor In-circuit contact monitor

1990-11-19

1992-03-17

Spar, Robert J.

Railway switches and signals

Interlocking

Switch or signal indicators

246253, 340644, G08C 1904, B61L 1908

Patent

active

050961470

ABSTRACT:
An in-circuit contact monitor for providing reliable and safe detection of the position of fail safe, or vital, circuit contacts in railroad signaling and inter-locking control circuits comprises an impedance network arranged in a bridge configuration, a low-power, high-frequency signal source, an isolation transformer, and a pair of DC blocking capacitors. The low-power, high-frequency AC source provides energy for an isolated circuit which is used in detecting the toggling of an individual circuit contact. The circuit is configured such that the vital circuitry, which is connected to the circuit contact, is completely isolated from the DC components generated by the low-power, high-voltage AC source. The isolation transformer acts to isolate the monitor system from the in-circuit contact monitor circuitry and thus the vital circuitry.

REFERENCES:
patent: 1862212 (1932-06-01), Dowling
patent: 1896370 (1933-03-01), Peter
patent: 2575447 (1951-11-01), Gossick
patent: 3215996 (1965-11-01), Schwartz et al.
patent: 3587096 (1971-06-01), Teichmann
patent: 3746880 (1973-07-01), Iritani et al.
patent: 3845363 (1974-10-01), Billion
patent: 3936705 (1976-02-01), Billion
patent: 4322769 (1982-03-01), Cooper
patent: 4580062 (1986-04-01), MacLaughlin
patent: 4672310 (1987-06-01), Sayed
patent: 4689570 (1987-08-01), Ohgaki et al.
patent: 4691143 (1987-09-01), Lange

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