Patent US3544315A successfully refreshed from Google Patents.
Patent US4508997A successfully refreshed from Google Patents.
US4508997A
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US
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Lighting control system
Assignee: Delmatic Ltd
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Filing: 1983-04-15
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Granted: 1985-04-02
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Expires: 2003-04-15
Abstract
Abstract Lights (LP) are controlled by a control unit (CU) which, in response to a remotely and/or automatically generated signal (MASTER OFF), interrupts the lighting temporarily (preferably by repeatedly flashing them on and off) to provide a warning and switches off the lighting after a delay period unless inhibited by a local switch (S1).
Inventors
- 👤 John P. Woodnutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:54
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/02; H02M5/04; H02M5/22; H02M5/25; H02M5/257; H02M5/2573; H02M5/2576; H05; H05B; H05B47/00; H05B47/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
104 words
A lighting system comprising a plurality of lighting sub-circuits; a master control; local control units each arranged for operation in response to a signal from the master control to temporarily interrupt the lighting on one or more lighting sub-circuits associated with the respective local control unit during a delay period, to provide a warning, and to switch off the lighting at the end of the delay period; and a manually-operable switch associated with each local control unit, and actuable during the delay period to inhibit the switching off of said one or more lighting sub-circuits under the control of the respective local control unit.
Claim 2
Dependent Claim
104 words
A lighting system comprising a plurality of lighting sub-circuits; a master control; local control units each arranged for operation in response to a signal from the master control to temporarily interrupt the lighting on one or more lighting sub-circuits associated with the respective local control unit during a delay period, to provide a warning, and to switch off the lighting at the end of the delay period; and a manually-operable switch associated with each local control unit, and actuable during the delay period to inhibit the switching off of said one or more lighting sub-circuits under the control of the respective local control unit.
Claim 3
Dependent Claim
44 words
A lighting system according to claim 1 wherein each said local control unit is arranged to provide a warning on the one or more lighting sub-circuits associated with it consisting of repeated interruption of the lighting during some or all of said delay period.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-01 | 1988-10-01 | 1989-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-01 | 1992-10-01 | 1993-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-01 | 1996-10-01 | 1997-04-02 | $7700.00 | Window Closed / Lapsed |