US3819934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe solid state highway crossing protection apparatus
Assignee: Trane US Inc
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Filing: 1973-03-02
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Granted: 1974-06-25
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Expires: 1993-03-02
Abstract
Abstract Solid state static relays, with contact circuits including insulated signal couplers formed by light emitting diodes and light responsive transistors, are used as track circuit detectors and directional stick devices in highway crossing protection systems. Each relay control circuit requires modulated switching across control input terminals to condition that relay to an energized state which activates front contact couplers. Absence of the modulated switching or a continuous circuit across the terminals conditions the relay coil circuit to activate only back contact couplers. A solid state directional logic network for highway crossing protection is formed by a selected circuit arrangement of insulated coupler elements which fulfills in a fail-safe manner the Boolean functions representing the directional crossing protection logic. The crossing protection device is controlled through an output buffer circuit by other selected couplers representing the control functions by which the device is activated only for approaching trains.
Inventors
- 👤 J Kramer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:42
CPC Classifications
B; B61; B61L; B61L29/00; B61L29/24; B61L29/28; B61L29/286
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
429 words
A highway crossing protection system for a stretch of railroad track intersected by a highway, having a protection device at said crossing selectively activated to warn highway traffic of an approaching train occupying an approach warning section along each direction of movement, comprising in coMbination, a. first and second train detection means, one for each approach warning section, each responsive to the presence or absence of a train within the corresponding section or detecting the occupancy condition of that section, b. a static train detector relay means associated with each train detection means and coupled for registering the absence of a train in the corresponding warning section only when also supplied with a modulated control switching signal, c. a first plurality of insulated signal couplers controlled by the first static detector relay means to first and second states as a train absence or presence in the corresponding section is detected. d. a second plurality of insulated signal couplers controlled by the second static detector relay means to first and second states as a train absence or presence in the corresponding section is detected, e. direction registry means controlled jointly by said first and second plurality of signal couplers for registering the direction of a train approaching the crossing in an approach section and for retaining that direction registry while that train recedes from said crossing in the opposite approach section, f. another pair of static relay means associated with said direction registry means and activated only when also supplied with a modulated control switching signal, g. a third plurality of insulated signal ouplers selectively controlled by said direction registry static relay means to first and second states selectively as one or the other train direction is registered, h. each static direction registry relay means coupled to said first, second, and third pluralities of insulated signal couplers in a manner for selectively activating one predetermined direction relay means only to register the direction of an approaching train and for retaining that relay means activated until that train clears the opposite warning section during its receding movement from said crossing, i. a source of modulated switching signals coupled to each static relay means for providing a modulated switching signal to activate the relay when other required input conditions coexist, and j. control means for said protection device controlled jointly by said first, second, and third plurality of signal couplers for activating said device when an approaching train occupies one approach warning section and for deactivating said device when that train occupies only the other approach section while receding from said crossing.
Claim 2
Dependent Claim
429 words
A highway crossing protection system for a stretch of railroad track intersected by a highway, having a protection device at said crossing selectively activated to warn highway traffic of an approaching train occupying an approach warning section along each direction of movement, comprising in coMbination, a. first and second train detection means, one for each approach warning section, each responsive to the presence or absence of a train within the corresponding section or detecting the occupancy condition of that section, b. a static train detector relay means associated with each train detection means and coupled for registering the absence of a train in the corresponding warning section only when also supplied with a modulated control switching signal, c. a first plurality of insulated signal couplers controlled by the first static detector relay means to first and second states as a train absence or presence in the corresponding section is detected. d. a second plurality of insulated signal couplers controlled by the second static detector relay means to first and second states as a train absence or presence in the corresponding section is detected, e. direction registry means controlled jointly by said first and second plurality of signal couplers for registering the direction of a train approaching the crossing in an approach section and for retaining that direction registry while that train recedes from said crossing in the opposite approach section, f. another pair of static relay means associated with said direction registry means and activated only when also supplied with a modulated control switching signal, g. a third plurality of insulated signal ouplers selectively controlled by said direction registry static relay means to first and second states selectively as one or the other train direction is registered, h. each static direction registry relay means coupled to said first, second, and third pluralities of insulated signal couplers in a manner for selectively activating one predetermined direction relay means only to register the direction of an approaching train and for retaining that relay means activated until that train clears the opposite warning section during its receding movement from said crossing, i. a source of modulated switching signals coupled to each static relay means for providing a modulated switching signal to activate the relay when other required input conditions coexist, and j. control means for said protection device controlled jointly by said first, second, and third plurality of signal couplers for activating said device when an approaching train occupies one approach warning section and for deactivating said device when that train occupies only the other approach section while receding from said crossing.
Claim 3
Dependent Claim
33 words
said second circuit path completed when one detection relay means detects the corresponding one approach section unoccupied and said direction relays register a train receding from said crossing through the other approach section,
Claim 4
Dependent Claim
33 words
said second circuit path completed when one detection relay means detects the corresponding one approach section unoccupied and said direction relays register a train receding from said crossing through the other approach section,
Claim 5
Dependent Claim
71 words
A crossing protection system as defined in claim 1 in which, a. said modulated switching signal source is coupled to said static detector relay means through additional insulated signal couplers controlled by said source, and b. said modulated switching signal source is coupled to said static direction registry relay means through said first and second plurality of insulated signal couplers jointly with other additional insulated signal couplers controlled by said source.
Claim 6
Dependent Claim
93 words
a receiver coupled to the rails at said crossing on the opposite side of the highway from its associated transmitter and responsive only to track current having the distinctive frequency of the associated transmitter for providing an output signal when the corresponding section is unoccupied, b. each receiver being coupled by a separate insulated signal coupler to the associated detector relay coil circuit network, the coupling being also controlled by said switching signal source, for supplying a modulated activating signal to that relay coil circuit network when the corresponding approach section is unoccupied.
Claim 7
Dependent Claim
93 words
a receiver coupled to the rails at said crossing on the opposite side of the highway from its associated transmitter and responsive only to track current having the distinctive frequency of the associated transmitter for providing an output signal when the corresponding section is unoccupied, b. each receiver being coupled by a separate insulated signal coupler to the associated detector relay coil circuit network, the coupling being also controlled by said switching signal source, for supplying a modulated activating signal to that relay coil circuit network when the corresponding approach section is unoccupied.
Claim 8
Dependent Claim
16 words
a contact circuit of the other direction relay means activated when no train direction is registered,
Claim 9
Dependent Claim
16 words
a contact circuit of the other direction relay means activated when no train direction is registered,
Claim 10
Dependent Claim
25 words
A crossing protection system as defined in claim 2 in which, each insulated signal coupler comprises an illumination emitting diode and an illumination responsive semiconductor.
Claim 11
Dependent Claim
33 words
said third circuit path completed when the other detection relay means detects said other approach secTion unoccupied and said direction relays register a train receding from said crossing through said one approach section.
Claim 12
Dependent Claim
33 words
said third circuit path completed when the other detection relay means detects said other approach secTion unoccupied and said direction relays register a train receding from said crossing through said one approach section.
Claim 13
Dependent Claim
17 words
a contact circuit of the corresponding direction relay means activated when a train direction is registered, and
Claim 14
Dependent Claim
17 words
a contact circuit of the corresponding direction relay means activated when a train direction is registered, and
Claim 15
Dependent Claim
96 words
a contact circuit of the detection relay means of the corresponding approach section activated when a train is detected occupying that section, g. a modulation switching means coupled to each detection relay coil circuit and to the control circuit network of each direction relay means for providing the modulated switching input upon which relay activation depends, and h. a control circuit network for said crossing device, controlled by first, second, and third circuit paths and connected for normally holding said device inactivated and for activating said device only when all said circuit paths are simultaneously incomplete,
Claim 16
Dependent Claim
96 words
a contact circuit of the detection relay means of the corresponding approach section activated when a train is detected occupying that section, g. a modulation switching means coupled to each detection relay coil circuit and to the control circuit network of each direction relay means for providing the modulated switching input upon which relay activation depends, and h. a control circuit network for said crossing device, controlled by first, second, and third circuit paths and connected for normally holding said device inactivated and for activating said device only when all said circuit paths are simultaneously incomplete,
Claim 17
Dependent Claim
25 words
A crossing protection system as defined in claim 2 in which, each insulated signal coupler comprises a light emitting diode and a light responsive transistor.
Claim 18
Dependent Claim
135 words
A crossing protection system as defined in claim 4 in which each train detection means further includes, a. an alternating current overlay track circuit having a transmitter coupled to the rails at the remote end of the corresponding approach warning track section and a receiver coupled to the rails at said crossing on the opposite side of the highway from the associated transmitter, b. each transmitter supplying an alternating current of distinctive frequency through the rails to the associated receiver which is responsive only to an input of that frequency for providing an output signal, c. each receiver output beIng coupled by a separate insulated signal coupler controlled by said modulation switching source to the associated static detector relay means for supplying a modulated activating signal when the corresponding section is unoccupied by a train.
Claim 19
Dependent Claim
168 words
A highway crossing protection system for a stretch of track intersected by a highway, with a protection device at said crossing to warn highway traffic of the approach of trains within an approach warning section for each direction of train movement, comprising in combination, a. a train detection means for each approach warning section responsive to the presence of a train within that section and including a static type detector relay normally activated when the section is unoccupied by a train, b. a train direction registry means including a pair of static type direction relays activated at times for registering the direction of movement of a train traversing the stretch, one relay for a first direction and the other relay for a second direction, c. each static relay including a solid state coil circuit network and a plurality of contact circuits each comprising an insulated signal coupler, preselected contacts being active when said coil circuit is activated, the remaining contacts being active when said coil circuit is nonactivated,
Claim 20
Dependent Claim
168 words
A highway crossing protection system for a stretch of track intersected by a highway, with a protection device at said crossing to warn highway traffic of the approach of trains within an approach warning section for each direction of train movement, comprising in combination, a. a train detection means for each approach warning section responsive to the presence of a train within that section and including a static type detector relay normally activated when the section is unoccupied by a train, b. a train direction registry means including a pair of static type direction relays activated at times for registering the direction of movement of a train traversing the stretch, one relay for a first direction and the other relay for a second direction, c. each static relay including a solid state coil circuit network and a plurality of contact circuits each comprising an insulated signal coupler, preselected contacts being active when said coil circuit is activated, the remaining contacts being active when said coil circuit is nonactivated,
Claim 21
Dependent Claim
86 words
A crossing protection system as defined in claim 6 in which, a. each relay contact insulated signal coupler comprises an illumination emitting diode and an illumination responsive semiconductor so positioned that each semiconductor is responsive only to illumination from the associated diode, b. said modulated switching signal source is coupled to the diode of each said contact signal oupler for modulating the conducting period of each associated semiconductor to provide fail-safe characteristics to the operation of said direction relays and said protection device control circuit means.
Claim 22
Dependent Claim
80 words
A crossing protection system as defined in claim 6 in which, a. each relay contact insulated signal coupler comprises a light emitting diode and a light responsive transistor responsive only to illumination from the associated diode, b. said modulated switching signal source is coupled to the diode of each said contact signal coupler for modulating the conducting period of each associated transistor to provide fail-safe characteristics to the operation of said direction relays and said protection device control circuit means.
Claim 23
Dependent Claim
25 words
A crossing protection system as defined in claim 8 in which each train detection means further includes, a. an alternating current overlay track circuit comprising,
Claim 24
Dependent Claim
253 words
Control logic circuitry for a highway crossing protection system including an approach warning track section or each direction of train movement, each provided with means for detecting the presence of a train occupying that section, and a crossing protection device selectively activated for warning highway traffic of a train approach, comprising in combination, a. static relay means associated with each track section detection means and controlled thereby for registering the absence or presence of a train occupying the section, b. a pair of static relay means for selectively registering the direction of travel of a train while approaching and receding from said crossing, one relay of said pair activated for each direction of travel, c. each static relay means having a solid state coil circuit portion and a plurality of contact circuits each comprising an illumination emitting diode and an illumination responsive semiconductor, d. the contact circuits of each detection relay mean selectively activated by the associated coil circuit, some to indicate the corresponding section unoccupied and others to indicate the presence of a train occupying the corresponding section, e. the contact circuits of each direction registry relay means also selectively activated by the associated coil circuit, some to register a train movement in the corresponding direction and others to indicate absence of any movement direction registry, f. a control circuit network for activating each direction relay means to register a train approaching in the corresponding direction and for holding that relay activated until that train clears the opposite direction approach section, including,
Claim 25
Dependent Claim
253 words
Control logic circuitry for a highway crossing protection system including an approach warning track section or each direction of train movement, each provided with means for detecting the presence of a train occupying that section, and a crossing protection device selectively activated for warning highway traffic of a train approach, comprising in combination, a. static relay means associated with each track section detection means and controlled thereby for registering the absence or presence of a train occupying the section, b. a pair of static relay means for selectively registering the direction of travel of a train while approaching and receding from said crossing, one relay of said pair activated for each direction of travel, c. each static relay means having a solid state coil circuit portion and a plurality of contact circuits each comprising an illumination emitting diode and an illumination responsive semiconductor, d. the contact circuits of each detection relay mean selectively activated by the associated coil circuit, some to indicate the corresponding section unoccupied and others to indicate the presence of a train occupying the corresponding section, e. the contact circuits of each direction registry relay means also selectively activated by the associated coil circuit, some to register a train movement in the corresponding direction and others to indicate absence of any movement direction registry, f. a control circuit network for activating each direction relay means to register a train approaching in the corresponding direction and for holding that relay activated until that train clears the opposite direction approach section, including,
Claim 26
Dependent Claim
152 words
Control logic circuitry for a highway crossing protection system including an approach warning track section for each direction of train movement, each section provided with track circuit means for detecting the presence of a train occupying that section, and a crossing protection device activated at times for warning highway traffic of an approaching train, comprising in combination, a. a modulation switching means operable to provide a modulated switching signal, b. a detector means associated with each track circuit means and operable to a first and a second condition or detecting the presence or absence, respectively, of a train occupying the corresponding section, c. an AND circuit network for each detector means, controlled by the associated track circuit means and by said switching means, and connected for operating the corresponding detector means to its second condition only when the corresponding approach section is unoccupied by a train and a switching signal is present,
Claim 27
Dependent Claim
152 words
Control logic circuitry for a highway crossing protection system including an approach warning track section for each direction of train movement, each section provided with track circuit means for detecting the presence of a train occupying that section, and a crossing protection device activated at times for warning highway traffic of an approaching train, comprising in combination, a. a modulation switching means operable to provide a modulated switching signal, b. a detector means associated with each track circuit means and operable to a first and a second condition or detecting the presence or absence, respectively, of a train occupying the corresponding section, c. an AND circuit network for each detector means, controlled by the associated track circuit means and by said switching means, and connected for operating the corresponding detector means to its second condition only when the corresponding approach section is unoccupied by a train and a switching signal is present,
Claim 28
Dependent Claim
244 words
Control logic circuitry as defined in claim 11 in which, a. said AND circuit network for each detector means includes a first insulated signal coupler controlled by said switching means and a second insulated signal coupler connected for coupling the modulated switching signal and a section unoccupied signal from the corresponding track circuit means to that detector means, b. each detector means controls a plurality of other insulated signal couplers for activating some couplers when in its first condition and the remaining couplers when in its second condition, c. each direction registry means controls still another plurality of insulated signal couplers for activating some couplers when in its first condition and the remaining couplers when in its second condition, d. each first and second AND circuit network is couPled to said switching means by an insulated signal coupler for receiving a network modulating signal and further includes signal couplers of the controlling detector and registry means for performing AND logic functions to determine the existence of the required conditions for operating the associated direction registry means to its second condition, and e. said OR circuit network includes insulated signal couplers controlled by each detector means and each direction registry means for performing AND logic functions to determine the existence of at least one set of the required conditions for holding said crossing device inactive, and is coupled to said switching means by selected ones of the included couplers for receiving a network modulating signal.
Claim 29
Dependent Claim
25 words
Control logic circuitry as defined in claim 12 in which each insulated signal coupler comprises a light emitting diode and an associated light responsive transistor.
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) | 1977-06-24 | 1977-12-24 | 1978-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-24 | 1981-12-24 | 1982-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-24 | 1985-12-24 | 1986-06-25 | $7700.00 | Window Closed / Lapsed |