US4023034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light admitting means for photocell-controlled lighting fixture
Assignee: Individual
•
Filing: 1975-09-08
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Granted: 1977-05-10
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Expires: 1995-09-08
Abstract
Abstract Fixed indoor ceiling-mounted lighting fixtures can be inexpensively and simply dimmed automatically in response to natural daylight availability, by photocell-controlled relay. An illustration of the technique is shown for modification of a two-ballast four-lamp fluorescent fixture, to reduce consumption of electrical energy by fifty percent when daylight permits.
Inventors
- 👤 Ezra L. Schacht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:26
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0005; F; F21; F21V; F21V23/00; F21V23/04; F21V23/0442; F21V23/0464
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
50 words
Light-admitting means for recessed-troffer lighting-fixture, comprising: photocell-controlled relay within said lighting fixture compartment; cutting-edged coring tube having driving means for penetrating a ceiling; light-admitting conduit having light-impervious sheath of diameter smaller than inner diameter of said coring tube; and optical coupling means from said light-admitting conduit to said photocell-controlled relay.
Claim 2
Dependent Claim
50 words
Light-admitting means for recessed-troffer lighting-fixture, comprising: photocell-controlled relay within said lighting fixture compartment; cutting-edged coring tube having driving means for penetrating a ceiling; light-admitting conduit having light-impervious sheath of diameter smaller than inner diameter of said coring tube; and optical coupling means from said light-admitting conduit to said photocell-controlled relay.
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) | 1980-05-09 | 1980-11-08 | 1981-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-09 | 1984-11-08 | 1985-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-09 | 1988-11-08 | 1989-05-10 | $7700.00 | Window Closed / Lapsed |