US3927852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail-safe logic circuitry for vehicle transportation control
Assignee: SASIB SpA Bologna
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Filing: 1974-04-01
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Granted: 1975-12-23
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Expires: 1994-04-01
Abstract
Abstract Logic circuitry in a vehicle transportation system, such logic circuitry providing fail-safe operation utilizing solid-state circuits. The logic circuitry is described relative to control of a highway crossing indicator, such circuitry selectively producing a most restrictive output signal or a least restrictive output signal in accordance with traffic conditions to the crossing indicator. A vital signal is generated that is characteristically differentiated from other signals in the circuit. The vital signal is serially transferred through gate circuits by corresponding enable signals to each gate circuit. When and only when the vital signal has been transferred along a path of gate circuits and through the logic circuitry, the crossing indicator assumes a least restrictive mode of operation.
Inventors
- 👤 Henry C Sibley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:36
CPC Classifications
B; B61; B61L; B61L29/00; B61L29/24; B61L29/28; B61L29/288
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
315 words
A highway crossing control system for actuation of a warning indicator to provide a closure of the highway by a vehicle moving along a track crossing the highway, including a first track section across the highway and extending in a first direction from the highway, a second track section overlapping said first track section across the highway and extending in a second direction from the highway, a first and second track circuit corresponding to said first and second track section And sensing the occupancy and vacancy by a vehicle along the track in said corresponding first and second track sections, a first and second control circuit to actuate the highway crossing warning indicator; a first memory circuit included in said first control circuit, said first memory circuit being set by a vehicle proceeding from said first track section to said second track section and remaining set during the time such vehicle is detected in said first and second track sections, a second memory circuit included in said second control circuit, said memory circuit being set by a vehicle proceeding from said second track section to said first track section and remaining set during the time such vehicle is detected in said first and second track sections; said first control circuit responsive to said first and second memory circuits and providing means for actuating the highway crossing warning indicator when and only when a vehicle travelling in a direction from said first track secction to said second track section is sensed by said first track circuit in said first track section, and said second control circuit responsive to said first and second memory circuits and providing means for actuating the highway crossing warning indicator when and only when a vehicle travelling in a direction from said second track section to said first track section is sensed by said second track circuit in said second track section.
Claim 2
Dependent Claim
315 words
A highway crossing control system for actuation of a warning indicator to provide a closure of the highway by a vehicle moving along a track crossing the highway, including a first track section across the highway and extending in a first direction from the highway, a second track section overlapping said first track section across the highway and extending in a second direction from the highway, a first and second track circuit corresponding to said first and second track section And sensing the occupancy and vacancy by a vehicle along the track in said corresponding first and second track sections, a first and second control circuit to actuate the highway crossing warning indicator; a first memory circuit included in said first control circuit, said first memory circuit being set by a vehicle proceeding from said first track section to said second track section and remaining set during the time such vehicle is detected in said first and second track sections, a second memory circuit included in said second control circuit, said memory circuit being set by a vehicle proceeding from said second track section to said first track section and remaining set during the time such vehicle is detected in said first and second track sections; said first control circuit responsive to said first and second memory circuits and providing means for actuating the highway crossing warning indicator when and only when a vehicle travelling in a direction from said first track secction to said second track section is sensed by said first track circuit in said first track section, and said second control circuit responsive to said first and second memory circuits and providing means for actuating the highway crossing warning indicator when and only when a vehicle travelling in a direction from said second track section to said first track section is sensed by said second track circuit in said second track section.
Claim 3
Dependent Claim
35 words
The highway crossing control system of claim 1 including an inhibit circuit connecting said first and second memory circuit so that only one of said first and second memory circuits is set at any time.
Claim 4
Dependent Claim
84 words
The highway crossing system of claim 1 including a vital signal generator providing means for generating an alternating vital signal, a first input gate circuit providing means for gating said alternating vital signal to set said first memory circuit when said first track circuit detects a vehicle in said first track section, a second input gate circuit providing means for gating said alternating vital signal to set said second memory circuit when said second track circuit detects a vehicle in said second track section.
Claim 5
Dependent Claim
38 words
The highway crossing warning system of claim 1 wherein said first and second memory circuit each have a first input for setting each memory circuit and a second input for maintaining the memory circuit in a set state.
Claim 6
Dependent Claim
254 words
A highway crossing control system for actuation of a warning indicator to provide a closure of the highway by a vehicle moving along a track crossing the highway, including: a first track circuit detecting the occupancy or vacancy by a vehicle along the track on a first track portion extending across the highway and to one side of the highway, a second track circuit detecting the occupancy or vacancy of a vehicle along the track on a second track portion overlapping said first track portion across the highway and extending to the second side of the highway, a first memory circuit being set by a vehicle proceeding from said first track section to said second track section and remaining set during the time such vehicle is detected in said first and second track sections, a second memory circuit being set by a vehicle proceeding from said second track section to said first track section and remaining set during the time such vehicle is detected in said first and second track sections, a first actuation circuit responsive to said first and second memory circuits to actuate said highway warning when and only when a vehicle is approaching the highway from its one side and the vehicle is detected in said first track portion, and a second actuation circuit responsive to said first and second memory circuits to actuate said highway warning when and only when a vehicle is approaching the highway from its other side and the vehicle is detected in said second track portion.
Claim 7
Dependent Claim
254 words
A highway crossing control system for actuation of a warning indicator to provide a closure of the highway by a vehicle moving along a track crossing the highway, including: a first track circuit detecting the occupancy or vacancy by a vehicle along the track on a first track portion extending across the highway and to one side of the highway, a second track circuit detecting the occupancy or vacancy of a vehicle along the track on a second track portion overlapping said first track portion across the highway and extending to the second side of the highway, a first memory circuit being set by a vehicle proceeding from said first track section to said second track section and remaining set during the time such vehicle is detected in said first and second track sections, a second memory circuit being set by a vehicle proceeding from said second track section to said first track section and remaining set during the time such vehicle is detected in said first and second track sections, a first actuation circuit responsive to said first and second memory circuits to actuate said highway warning when and only when a vehicle is approaching the highway from its one side and the vehicle is detected in said first track portion, and a second actuation circuit responsive to said first and second memory circuits to actuate said highway warning when and only when a vehicle is approaching the highway from its other side and the vehicle is detected in said second track portion.
Claim 8
Dependent Claim
35 words
The highway crossing control system of claim 5 including an inhibit circuit connecting said first and second memory circuit so that only one of said first and second memory circuits is set at any time.
Claim 9
Dependent Claim
84 words
The highway crossing system of claim 5 including a vital signal generator providing means for generating an alternating vital signal, a first input gate circuit providing means for gating said alternating vital signal to set said first memory circuit when said first track circuit detects a vehicle in said first track section, a second input gate circuit providing means for gating said alternating vital signal to set said second memory circuit when said second track circuit detects a vehicle in said second track section.
Claim 10
Dependent Claim
38 words
The highway crossing warning system of claim 5 wherein said first and second memory circuit each have a first input for setting each memory circuit and a second input for maintaining the memory circuit in a set state.
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) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |