Patent US3868075A successfully refreshed from Google Patents.
US3868075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Jointless coded track circuits for railroad signal systems
Assignee: Trane US Inc
•
Filing: 1973-09-17
•
Granted: 1975-02-25
•
Expires: 1993-09-17
Abstract
Abstract Track currents are supplied to the rails of adjoining sections at each location through a track transformer whose secondary serves as a low impedance cross bond to divide the track into sections without insulated joints and to confine track circuit energy to a given zone. A track transmitter develops sufficient energy for rail currents with the selected different frequencies established by a separate oscillator unit for each adjoining section. A tuned track receiver for each section is independently coupled by pickup coils to the corresponding section rails in the vicinity of the cross bond to receive incoming track current of a different frequency from the other end. Each track current is coded at a selected rate in accord with corresponding advance traffic conditions. A received track current signal is demodulated by the corresponding receiver and applied through decoding units to a logic network which detects track section occupancy and determines the traffic condition. In accord with the registered traffic or occupancy conditions, the logic network selects from code rates provided by a bank of coding devices for modulating the applied track currents. The selected code rates modulate each oscillator output and thus the track transmitter output. If cab signals are used, a separate oscillator, also controlled by the logic means, supplies coded cab signal energy to an approaching train through the track transmitter.
Inventors
- 👤 Frank V Blazek
- 👤 Thomas C Vaughn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:19
CPC Classifications
B; B61; B61L; B61L23/00; B61L23/08; B61L23/14; B61L23/16; B61L23/168
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
409 words
A track circuit arrangement for a stretch of railroad track having electrically continuous rails, comprising in combination, a. a low alternating current impedance cross bond connected across the rails at selected locations for dividing said stretcH into a series of track sections, b. a track current transmitter means at each location coupled to the corresponding cross bond and operable for supplying track current to the section in each direction from the associated bond, 1. each section current having a different preselected frequency and different from the preselected frequencies of a prefixed number of successive sections in each direction from that particular location, c. a frequency determining means at each location coupled to the associated transmitter means for establishing the preselected frequency of the track current supplied to each section adjoining that location, d. a separate tuned track receiver coupled to the rails on each side of the cross bond connections at each location and responsive only to track current from the transmitter means at the other end of the corresponding section for producing an output signal, e. a single logic network means at each location connected to receive the output signal of each track receiver and responsive thereto for registering a nonoccupied indication of the corresponding section when the signal is present and an occupied indication when the signal is absent, f. a plurality of traffic condition signal generators at each location, each producing a distinct signal representing a predetermined advance traffic condition along the stretch of track, and g. a plurality of decoder units, one for each advance trafffic condition signal, associated at each location with each track receiver and coupled to said logic network means, h. said signal generators selectively coupled by said logic network means to said frequency determining means for separately modulating the track current supplied to each adjoining track section in accordance with the detected advance traffic condition in the corresponding direction along said stretch, i. each track receiver further operable for demodulating the received track current to which it is responsive to produce a traffic condition output signal corresponding to the modulating signal selected at the next adjacent location in that direction, j. each plurality of decoder units connected for receiving the output signal from the associated track receiver and responsive thereto for actuating said logic network means to selectively couple a signal generator to modulate the track current supplied to the other track section in accordance with the detected advance traffic condition.
Claim 2
Dependent Claim
409 words
A track circuit arrangement for a stretch of railroad track having electrically continuous rails, comprising in combination, a. a low alternating current impedance cross bond connected across the rails at selected locations for dividing said stretcH into a series of track sections, b. a track current transmitter means at each location coupled to the corresponding cross bond and operable for supplying track current to the section in each direction from the associated bond, 1. each section current having a different preselected frequency and different from the preselected frequencies of a prefixed number of successive sections in each direction from that particular location, c. a frequency determining means at each location coupled to the associated transmitter means for establishing the preselected frequency of the track current supplied to each section adjoining that location, d. a separate tuned track receiver coupled to the rails on each side of the cross bond connections at each location and responsive only to track current from the transmitter means at the other end of the corresponding section for producing an output signal, e. a single logic network means at each location connected to receive the output signal of each track receiver and responsive thereto for registering a nonoccupied indication of the corresponding section when the signal is present and an occupied indication when the signal is absent, f. a plurality of traffic condition signal generators at each location, each producing a distinct signal representing a predetermined advance traffic condition along the stretch of track, and g. a plurality of decoder units, one for each advance trafffic condition signal, associated at each location with each track receiver and coupled to said logic network means, h. said signal generators selectively coupled by said logic network means to said frequency determining means for separately modulating the track current supplied to each adjoining track section in accordance with the detected advance traffic condition in the corresponding direction along said stretch, i. each track receiver further operable for demodulating the received track current to which it is responsive to produce a traffic condition output signal corresponding to the modulating signal selected at the next adjacent location in that direction, j. each plurality of decoder units connected for receiving the output signal from the associated track receiver and responsive thereto for actuating said logic network means to selectively couple a signal generator to modulate the track current supplied to the other track section in accordance with the detected advance traffic condition.
Claim 3
Dependent Claim
39 words
said corresponding receiver means further responsive to any interruption of the rail connections of the second transformer winding at the corresponding adjacent location for actuating the associated logic network means to register a track occupied condition for that section.
Claim 4
Dependent Claim
39 words
said corresponding receiver means further responsive to any interruption of the rail connections of the second transformer winding at the corresponding adjacent location for actuating the associated logic network means to register a track occupied condition for that section.
Claim 5
Dependent Claim
93 words
A track circuit arrangement as defined in claim 1 in which said frequency determining means at each location includes, a. a separate oscillator unit for each track section operable to provide an output signal of a preselected frequency different from the signal frequency of the associated oscillator unit and of each oscillator unit at said prefixed number of successive locations, b. said oscillator units connected to apply the output signals to said track transmitter means for jointly establishing the track current frequency supplied to the rails at the preselected frequency for each section.
Claim 6
Dependent Claim
66 words
A track circuit arrangement as defined in claim 2 which further includes at each location, another oscillator unit controlled by said logic means to provide a distinct cab signal frequency, the same at each location, when an approaching train is detected occupying either adjoining section and connected to said track transmitter means for also supplying a track current to said rails having said cab signal frequency.
Claim 7
Dependent Claim
184 words
A track circuit arrangement as defined in claim 3 in which the plurality of traffic condition generators at each location comprises, a. a plurality of code transmitters, each producing distinctive code rate signals representing a different predetermined advance traffic condition along the stretch of track, b. said code transmitters selectively coupled by said logic network means to said oscillator units for separately coding the track current supplied to each adjoining trAck section at that location in accordance with the detected advance traffic condition in the corresponding direction along said stretch, c. each track receiver further operable for demodulating the received coded track current to which it is responsive to produce output signals at a code rate corresponding to the code rate signal supplied at the other end of the corresponding section, d. each plurality of decoder units connected for receiving the code rate output signals from the associated track receiver and responsive thereto for actuating said logic network means to selectively couple a code transmitter to code the track current supplied to the other track section in accordance with the detected advance traffic condition.
Claim 8
Dependent Claim
69 words
A track circuit arrangement as defined in claim 4 which further includes at least at selected locations, a. a pair of wayside signals, each operable for controlling train movement in one direction past the corresponding location, b. each signal controlled by the associated logic network for displaying to an approaching train a speed command signal indication selected in accordance with the advance traffic conditions detected for the corresponding direction.
Claim 9
Dependent Claim
73 words
A track circuit arrangement as defined in claim 5 which further includes, a. a pair of energy pickup coils associated with each track receiver and positioned one coil in inductive relationship with each rail of the corresponding section in the vicinity of said cross bond connections, b. each pair of coils connected for supplying to the associated receiver the energy induced in said coils by the track currents flowing in the section rails.
Claim 10
Dependent Claim
58 words
A track circuit arrangement as defined in claim 6 in which, at each location, a. said low impedance cross bond is the secondary winding of a track transformer which also has a primary winding, b. said track current transmitter means is connected to the primary winding of said track transformer to supply the track currents to said rails.
Claim 11
Dependent Claim
374 words
In a track circuit arrangement for a stretch of railroad track having electrically continuous rails, at each of selected locations, the combination comprising, a. a track transformer including a first winding and a second low alternating current impedance winding connected across the rails of said track at the selected location to divide said stretch into successive sections, b. a track current transmitter connected to said first winding of the associated transformer for supplying alternating current energy to the rails of each section adjoining that location, c. a frequency determining means connected to the associated transmitter for establishing a different predetermined frequency for the alternating current supplied to the rails of each adjoining section, each frequency determining means also having frequencies different than those at a preset number of successive locations in each direction from that location, d. a separate receiver means coupled to the rails on each side of the second transformer winding rail connections at that location and tuned to a predetermined frequency for receiving only current of a frequency transmitted from the other end of the corresponding section, e. a plurality of coding devices, each operable for producing a distinct advance traffic condition code signal for at times modulating the track current supplied to the rails of each section, f. a separate plurality of decoding units coupled to each receiver means, each decoding unit responsive only to a predetermined one of the plurality of traffic condition code signals, g. each receiver means responsive to the received code signal carried by current for developing a traffic condition code signal output in accordance with the modulation by the received track current and connected for applying the output signal to the associated decoding units, and h. a logic network means controlled by both associated pluralities of decoding units for detecting the ocCupancy condition of each adjoining section in accordance with the receipt or nonreceipt of a traffic condition code signal from each section by the corresponding receiver means, i. said devices coupled to said frequency determining means by said logic network means for selectively modulating each track current with a code signal predetermined in accordance with the advance traffic condition code signal received from the decoding units associated with the other track section receiver means.
Claim 12
Dependent Claim
374 words
In a track circuit arrangement for a stretch of railroad track having electrically continuous rails, at each of selected locations, the combination comprising, a. a track transformer including a first winding and a second low alternating current impedance winding connected across the rails of said track at the selected location to divide said stretch into successive sections, b. a track current transmitter connected to said first winding of the associated transformer for supplying alternating current energy to the rails of each section adjoining that location, c. a frequency determining means connected to the associated transmitter for establishing a different predetermined frequency for the alternating current supplied to the rails of each adjoining section, each frequency determining means also having frequencies different than those at a preset number of successive locations in each direction from that location, d. a separate receiver means coupled to the rails on each side of the second transformer winding rail connections at that location and tuned to a predetermined frequency for receiving only current of a frequency transmitted from the other end of the corresponding section, e. a plurality of coding devices, each operable for producing a distinct advance traffic condition code signal for at times modulating the track current supplied to the rails of each section, f. a separate plurality of decoding units coupled to each receiver means, each decoding unit responsive only to a predetermined one of the plurality of traffic condition code signals, g. each receiver means responsive to the received code signal carried by current for developing a traffic condition code signal output in accordance with the modulation by the received track current and connected for applying the output signal to the associated decoding units, and h. a logic network means controlled by both associated pluralities of decoding units for detecting the ocCupancy condition of each adjoining section in accordance with the receipt or nonreceipt of a traffic condition code signal from each section by the corresponding receiver means, i. said devices coupled to said frequency determining means by said logic network means for selectively modulating each track current with a code signal predetermined in accordance with the advance traffic condition code signal received from the decoding units associated with the other track section receiver means.
Claim 13
Dependent Claim
101 words
A track circuit arrangement as defined in claim 8 in which each frequency determining means comprises, a. a separate oscillator unit for each track section adjoining that location, operable to provide an output signal frequency of the associated oscillator unit and of each oscillator unit at said preset number of successive locations, b. said oscillator units at a location controlled by the coding devices selectively coupled thereto by the associated logic means and connected to said track transmitter means for jointly establishing the predetermined frequency and the modulating code signal for the track current supplied to the rails of each section.
Claim 14
Dependent Claim
69 words
A track circuit arrangement as defined in claim 9 which further includes at each location, another oscillator unit controlled by said logic network means to provide a distinct cab signal frequency, the same at each location, when an approaching train is detected occupying either adjoining section and connected to said track transmitter means for also supplying a code modulated track current to said rails having said cab signal frequency.
Claim 15
Dependent Claim
108 words
A track circuit arrangement as defined in claim 10 in which, a. each low impedance second transformer winding terminates the modulated track current supplied from the track transmitter at each adjacent location, and which each location further includes, b. a pair of pickup coils inductively coupled to the rails on each side of the second transformer winding, one coil of each pair positioned in inductive relationship adjacent each rail in the vicinity of the associated second winding rail connections, c. each pair of coils connected for supplying to the corresponding receiver means the energy induced in said coils by the modulated track currents flowing in the section rails,
Claim 16
Dependent Claim
67 words
A track circuit arrangement as defined in claim 11, in which each location further includes, a. a pair of wayside signals, each operable for controlling train movement in one direction past the corresponding location, b. each signal controlled by the associated logic network for displaying to an approaching train a speed command signal indication selected in accordance with the advance traffic conditions detected for the corresponding direction.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |