US3618014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable indication control signal
Assignee: 3M Co
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Filing: 1969-08-27
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Granted: 1971-11-02
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Expires: 1989-08-27
Abstract
Abstract A traffic signal, appearing from a distance as a simple warning light, converts progressively into an instructional signal as viewed during the approach.
Inventors
- 👤 Gunnar R Ljungkull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:54
CPC Classifications
G; G08; G08G; G08G1/00; G08G1/09; G08G1/095
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
47 words
A visual control panel having light-transmitting indicia and background areas and including narrow louver means within said background areas for progressively reducing the proportion of transmitted light reaching a viewing station from said background areas as said station approaches a point adjacent an edge of said panel.
Claim 2
Dependent Claim
47 words
A visual control panel having light-transmitting indicia and background areas and including narrow louver means within said background areas for progressively reducing the proportion of transmitted light reaching a viewing station from said background areas as said station approaches a point adjacent an edge of said panel.
Claim 3
Dependent Claim
23 words
The control panel of claim 1 wherein said louver means are thin, parallel, and nontransparent, and are uniformly spaced throughout said background areas.
Claim 4
Dependent Claim
20 words
An illuminating device comprising the control panel of claim 2 in combination with light source means for supplying light therethrough.
Claim 5
Dependent Claim
24 words
The device of claim 3 wherein said source means is a traffic signal comprising a light source, a specular reflector, and a light-scattering lens.
Claim 6
Dependent Claim
22 words
The device of claim 3 wherein said louvers are disposed with their lateral axis at an upward slant from the light source.
Claim 7
Dependent Claim
15 words
The device of claim 3 wherein said panel is slanted upwardly toward said light source.
Claim 8
Dependent Claim
18 words
The device of claim 6 wherein said louvers are disposed with their lateral axis perpendicular to said panel.
Claim 9
Independent Claim
70 words
The method of alerting and informing traffic approaching a control point comprising placing, at a viewing location adjacent said control point, a control device comprising a visual control panel having light-transmitting indicia and background areas and including narrow louver means within said background areas in combination with light source means for supplying light therethrough, and with said louvers disposed at the angle of maximum light-controlling effectiveness for the approaching traffic.
Claim 10
Independent Claim
70 words
The method of alerting and informing traffic approaching a control point comprising placing, at a viewing location adjacent said control point, a control device comprising a visual control panel having light-transmitting indicia and background areas and including narrow louver means within said background areas in combination with light source means for supplying light therethrough, and with said louvers disposed at the angle of maximum light-controlling effectiveness for the approaching traffic.
Claim 11
Independent Claim
75 words
The method of providing a directional traffic signal, comprising placing a directional control panel, having light-transmitting indicia and background areas and including thin, narrow, parallel, nontransparent, uniformly spaced louver means within said background areas, and having said image areas designed to provide the desired directional signal, directly in front of a nondirectional traffic signal which supplies light over the entire area of said panel and with said louvers disposed at the angle of maximum effectiveness.
Claim 12
Independent Claim
75 words
The method of providing a directional traffic signal, comprising placing a directional control panel, having light-transmitting indicia and background areas and including thin, narrow, parallel, nontransparent, uniformly spaced louver means within said background areas, and having said image areas designed to provide the desired directional signal, directly in front of a nondirectional traffic signal which supplies light over the entire area of said panel and with said louvers disposed at the angle of maximum effectiveness.
Claim 13
Dependent Claim
34 words
The method of claim 9 wherein said panel is placed at an upward slant toward said light source and said louvers are disposed with their lateral axis perpendicular to the surface of said panel.
Claim 14
Dependent Claim
28 words
The panel of claim 2 wherein said louver means are not greater than about 0.03 inch in width and are spaced apart not more than about 0.01 inch.
References Cited (Backward Citations)
US2540389A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |