US3697736A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Airfield inset runway light
Assignee: Laur Knudsen Nordisk Elektricitets Selskab AS
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Filing: 1970-11-24
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Granted: 1972-10-10
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Expires: 1990-11-24
Abstract
Abstract In an airfield inset runway light a prism of substantially rhombic cross section is mounted in a housing with the major axis of the rhomb in substantially horizontal position and the prism is illuminated from two sides below the major axis in order to radiate rays from the upper surfaces of the prism so that the radiated rays form a small angle with the horizontal direction.
Inventors
- 👤 Erik Frederiksen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:32
CPC Classifications
B; B64; B64F; B64F1/00; B64F1/18; B64F1/20; B64F1/205
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
59 words
An inset runway light for an airfield comprising: a housing, a prism having a rhombic cross section mounted within said housing with the major axis of the rhomb in a substantially horizontal plane, and means for illuminating the bottom surfaces of said prism whereby light is directed from the upper surfaces of said prism in two substantially opposite directions.
Claim 2
Dependent Claim
59 words
An inset runway light for an airfield comprising: a housing, a prism having a rhombic cross section mounted within said housing with the major axis of the rhomb in a substantially horizontal plane, and means for illuminating the bottom surfaces of said prism whereby light is directed from the upper surfaces of said prism in two substantially opposite directions.
Claim 3
Dependent Claim
62 words
An inset runway light as in claim 1 further comprising a cover mounted over said housing, said cover including an aperture for mounting said prism, a rib member extending transversely across said housing for protecting said prism from wheel pressure, and plane surfaces on each side of said rib member, said surfaces sloping from the circumference of said cover towards said prism.
Claim 4
Dependent Claim
65 words
An inset runway light as in claim 1 wherein the top edge of said prism is chamfered, and said means for illuminating include a light source mounted within each quadrant formed by said chamfered edge and said rib member, and said housing further includes a reflector for each light source mounted to reflect light onto and through a respective one of the lower prism surfaces.
Claim 5
Dependent Claim
30 words
An inset runway light as in claim 3 wherein the light rays emitted from the upper priSm surfaces have an angle of approximately 3.5* with respect to the horizontal plane.
Claim 6
Dependent Claim
26 words
An inset runway light as in claim 2 wherein the upper surfaces of said prism extend above said opening to the under surface of said cover.
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) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |