US3753223A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System to determine the directional mode of travel of vehicles on a roadway
Assignee: 3M Co
•
Filing: 1971-08-16
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Granted: 1973-08-14
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Expires: 1991-08-16
Abstract
Abstract Method and apparatus for automatically determining within a vehicle the directional mode of the vehicle on a roadway, directional mode being a description of the direction the vehicle is traveling and/or the orientation of the vehicle. The method distinguishes between at least two directional modes, using one or more discrete magnetic-field-producing means installed on roadways and magnetic-flux-sensors in vehicles. The flux-sensors develop a standard first electric signal by travel of the vehicles in a first directional mode over the magnetic-fieldproducing means and a second electric signal different from the first signal by travel of the vehicles in a second directional mode over the magnetic-field-producing means. Electric circuitry in the vehicles distinguishes between the first and second signals and actuates mechanism in the vehicles that registers the directional mode in which the vehicles are traveling on the roadways. One use of the invention is to limit wrong-way travel on one-way roadways, the second electric signal occurring only when the vehicles are traveling in the wrong direction and the registering mechanism taking the form of travel-inhibiting mechanism that warns a driver or automatically stops the vehicle.
Inventors
- 👤 R Fayling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:31
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/01
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
169 words
A method for determining in which of at least two different directional modes a vehicle is traveling on a roadway comprising A. installing one or more discrete magnetic-field-producing means on the roadway each adapted to provide a magnetic field that may be sensed by magnetic-field-sensing means traveling over the roadway and through said field to develop in said magnetic-field-producing means at least a standard first electric signal for travel in a first directional mode and a standard second electric signal different from the first signal for travel in a second directional mode; B. equipping the vehicle with magnetic-field-sensing means adapted to develop said signals; C. equipping the vehicle with mechanism adapted to register the directional mode of travel of the vehicle; and D. equipping the vehicle with electric circuitry electrically connected between the magnetic-field-sensing means and the registering mechanism and adapted to distinguish between the first and second electric signals and to actuate the registering mechanism in accordane with which of the signals is generated in the magnetic-field-sensing means.
Claim 2
Independent Claim
169 words
A method for determining in which of at least two different directional modes a vehicle is traveling on a roadway comprising A. installing one or more discrete magnetic-field-producing means on the roadway each adapted to provide a magnetic field that may be sensed by magnetic-field-sensing means traveling over the roadway and through said field to develop in said magnetic-field-producing means at least a standard first electric signal for travel in a first directional mode and a standard second electric signal different from the first signal for travel in a second directional mode; B. equipping the vehicle with magnetic-field-sensing means adapted to develop said signals; C. equipping the vehicle with mechanism adapted to register the directional mode of travel of the vehicle; and D. equipping the vehicle with electric circuitry electrically connected between the magnetic-field-sensing means and the registering mechanism and adapted to distinguish between the first and second electric signals and to actuate the registering mechanism in accordane with which of the signals is generated in the magnetic-field-sensing means.
Claim 3
Dependent Claim
32 words
The method of claim 1 in which the discrete magnetic-field-producing means is at least one magnet comprising a tough organic polymeric matrix and particles of magnetic material uniformly distributed through the matrix.
Claim 4
Dependent Claim
26 words
The method of claim 2 in which said magnet extends transverse to the length of the roadway over at least a substantial width of the roadway.
Claim 5
Dependent Claim
35 words
The method of claim 1 in which the discrete magnetic-field-producing means is at least one magnet shaped in a configuration that is asymmetrical with respect to a line transverse to the length of the roadway.
Claim 6
Dependent Claim
24 words
The method of claim 1 in which the discrete magnetic-field-producing means is a current-carrying electrical conductor extending transverse to the length of the roadway.
Claim 7
Dependent Claim
47 words
The method of claim 1 in which a plurality of discrete magnetic-field-producing means are regularly spaced along the length of the roadway and constitute a track continually providing information to vehicles traveling on the roadway, the track being characterized in that it does not exhibit bidirectional symmetry.
Claim 8
Dependent Claim
65 words
The method of claim 1 for limtiing wrongway travel on a one-way roadway in which the magnetic-field-sensing means develops different electric signals for different directions of travel through the magnetic field provided by said magnetic-field-producing means; the registering mechanism comprises traVel-inhibiting mechanism; and the travel-inhibiting mechanism is actuated when an electric signal corresponding to the ''''wrong'''' direction of travel is developed in the magnetic-field-sensing means.
Claim 9
Dependent Claim
31 words
The method of claim 7 in which the travel-inhibiting mechanism automatically stops the vehicle when an electric signal corresponding to the ''''wrong'''' direction of travel is developed in the magnetic-field-sensing means.
Claim 10
Dependent Claim
62 words
The method of claim 1 for determining in which of four directional modes a vehicle is traveling on a roadway, chacterized in that the magnetic-field-sensing means comprises a horizontal-axis sensor, and the magnetic-field-producing means provides a magentic field such that four different standard electric signals are developed in said magnetic-field-sensing means for travel of the magnetic-field-sensing means in four different directional modes.
Claim 11
Dependent Claim
55 words
The method of claim 9 in which the magnetic-field-producing means a) exhibits geometric asymmetry with respect to a line transverse to the length of the roadway or b) comprises at least three magnetic-field-producing sections, at least two of which are of different polarity or are spaced an amount different than the other sections are spaced.
Claim 12
Dependent Claim
44 words
The method of claim 1 for determining in which of four directional modes a vehicle is traveling on a raodway, characterized in that the magnetic fueld sensing means comprises two sensors with perpendicularly oriented axes, or a single sensor with an obliquely oriented axis.
Claim 13
Dependent Claim
168 words
Apparatus for installation in a vehicle to determine the directional mode of the vehicle when the vehicle is traveling on a roadway equipped with one or more discrete magnetic-field-producing means each adapted to provide a magnetic field that may be sensed by magnetic-field-sensing means traveling over the magnetic-field-producing means and through said field to develop in said magnetic-field-sensing means at least a standard first electric signal for travel in a first directional mode and a standard second electric signal different from the first signal for travel in a second directional mode; the apparatus comprising A. a magnetic-field-sensing means adapted to be installed on the vehicle in position to develop said signals; B. mechanism adapted to register the directional mode of travel of the vehicle; and C. electric circuitry electrically connected between the magnetic-field-sensing means and the registering mechanism and adapted to distinguish between the first and second electric signals and to actuate the registering mechanism in accordance with which of the signals is generated in the magnetic-field-sensing means.
Claim 14
Dependent Claim
168 words
Apparatus for installation in a vehicle to determine the directional mode of the vehicle when the vehicle is traveling on a roadway equipped with one or more discrete magnetic-field-producing means each adapted to provide a magnetic field that may be sensed by magnetic-field-sensing means traveling over the magnetic-field-producing means and through said field to develop in said magnetic-field-sensing means at least a standard first electric signal for travel in a first directional mode and a standard second electric signal different from the first signal for travel in a second directional mode; the apparatus comprising A. a magnetic-field-sensing means adapted to be installed on the vehicle in position to develop said signals; B. mechanism adapted to register the directional mode of travel of the vehicle; and C. electric circuitry electrically connected between the magnetic-field-sensing means and the registering mechanism and adapted to distinguish between the first and second electric signals and to actuate the registering mechanism in accordance with which of the signals is generated in the magnetic-field-sensing means.
Claim 15
Dependent Claim
52 words
Apparatus of claim 12 for limiting wrong-way travel on one-way roadways in which the magnetic-field-sensing means develops different signals for different directions of travel of the vehicle, and the registering mechanism comprises travel-inhibiting mechanism actuated when an electric signal corresponding to the ''''wrong'''' direction of travel is developed in the magnetic-field-sensing means.
Claim 16
Dependent Claim
30 words
Apparatus of claim 13 in which the travel-inhibiting mechanism automatically stops the vehicle when an electric signal corresponding to the ''''wrong'''' direction of travel is developed in the magnetic-field-sensing means.
Claim 17
Dependent Claim
13 words
In combination, a vehicle and apparatus of claim 12 installed on the vehicle.
References Cited (Backward Citations)
US3044043A
Cited
US3493923A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-13 | 1977-02-12 | 1977-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-13 | 1981-02-12 | 1981-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-13 | 1985-02-12 | 1985-08-14 | $7700.00 | Window Closed / Lapsed |