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US4417229A Expired / Lapsed US ⏱️ 0.0 years remaining

Means for use on a railroad to distinguish between traction current and signal current

Assignee: Siemens Industry Inc
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Filing: 1982-05-06
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Granted: 1983-11-22
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Expires: 2002-05-06
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Abstract

Abstract Means for differentiating between traction current and signal current in an electrified railroad includes a first input transformer providing an input signal of the same frequency and phase as the track signal current. A second input transformer is connected to the track to provide a track signal. There are means for comparing the phase and frequency of the input signal and the track signal and means responsive to an output from the comparison means indicating a correct comparison for providing a relay driving signal.

Inventors

  • 👤 H. James Wilson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 10:54
CPC Classifications
B; B61; B61L; B61L1/00; B61L1/18; B61L1/181; B61L1/187; B61L1/20; B61L23/00; B61L23/08; B61L23/14; B61L23/16; B61L23/166

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 87 words
Means for distinguishing between non-signal current and signal current for use on a railroad including a first input means providing an input signal of the same frequency and phase as track signal current, a second input means connected to the track to provide a track signal, means for comparing the phase and frequency of said input signal and track signal, and means responsive to said comparison means for providing a relay driving signal when the input signal and the track signal have the same phase and frequency.
Claim 2
Dependent Claim 87 words
Means for distinguishing between non-signal current and signal current for use on a railroad including a first input means providing an input signal of the same frequency and phase as track signal current, a second input means connected to the track to provide a track signal, means for comparing the phase and frequency of said input signal and track signal, and means responsive to said comparison means for providing a relay driving signal when the input signal and the track signal have the same phase and frequency.
Claim 3
Dependent Claim 31 words
The means of claim 1 further characterized in that said phase and frequency comparison means are separate, with an output from said comparison means requiring correspondence of both phase and frequency.
Claim 4
Dependent Claim 52 words
The means of claim 2 further characterized in that said phase comparison means includes a J/K flip-flop in which one of said input means is connected to the J and K terminals, with the other input means being connected to the clock terminal, with signals of the same providing a transitory output.
Claim 5
Dependent Claim 61 words
The means of claim 3 further characterized by and including a detector connected to the output of said J/K flip-flop, with the output of said detector being a direct current signal, with the means responsive to said comparison means including a chopper for converting said direct current signal into a signal of a predetermined frequency to provide a relay driving signal.
Claim 6
Dependent Claim 72 words
The means of claim 2 further characterized in that said frequency comparison means includes first and second counters, each connected to one of said input means and each being arranged to reset after the count reaches a set number which is the same for both counters, signals of the same frequency at the counter inputs providing a comparison output of the input frequency divided by twice the set number of said counters.
Claim 7
Dependent Claim 40 words
The means of claim 5 further characterized by and including a NOR flip-flop connected to the output of both of said counters, and a detector connected to said NOR flip-flop providing a direct current signal when there is frequency comparison.
Claim 8
Dependent Claim 24 words
The means of claim 1 further characterized by and including isolation means connected between said input means and said frequency and phase comparison means.
Claim 9
Dependent Claim 31 words
The means of claim 1 further characterized in that said first input means provides the power for said frequency and phase comparison means and means for providing a relay driving signal.
Claim 10
Dependent Claim 84 words
Means for use on an electrified railroad for sensing a selected signal current including a first input means providing an input signal of a selected predetermined phase and frequency, a second intput means connected to the track to provide a track signal, means for comparing the phase and frequency of said selected signal and said track signal, and means responsive to said comparison means for providing a relay drive signal when the input signal and the track signal have the same phase and frequency.
Claim 11
Dependent Claim 84 words
Means for use on an electrified railroad for sensing a selected signal current including a first input means providing an input signal of a selected predetermined phase and frequency, a second intput means connected to the track to provide a track signal, means for comparing the phase and frequency of said selected signal and said track signal, and means responsive to said comparison means for providing a relay drive signal when the input signal and the track signal have the same phase and frequency.
Claim 12
Dependent Claim 17 words
The means of claim 9 further characterized in that said phase and frequency comparison means are separate.

References Cited (Backward Citations)

US3428868A Cited
US3715669A Cited
US3992698A Cited
US4065081A Cited
US4222045A Cited
US4320881A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-21 1987-05-23 1987-11-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-21 1991-05-23 1991-11-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-21 1995-05-23 1995-11-22 $7700.00 Window Closed / Lapsed

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