Patent US4961028A successfully refreshed from Google Patents.
US4961028A
Expired / Lapsed
US
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Lighting equipment
Assignee: HAYASHI TOKEI KOGYO A CORP OF JAPAN KK
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Filing: 1988-11-10
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Granted: 1990-10-02
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Expires: 2008-11-10
Abstract
Abstract Equipment for lighting a work area has a plurality of light sources, at least one of which is usually lighted; the others are spare light sources and are usually turned off. The equipment has means such as an optical fiber to conduct light from the light source to the work area. Converting means is provided with the equipment to distribute electric power selectively to the light sources. Detecting means is also installed in the equipment to detect cutting off of the light source which is in the lighted condition. The converting means changes the distribution of the output from the power supply to a light source other than the light source which was cut off.
Inventors
- 👤 Hiroaki Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:27
CPC Classifications
H; H05; H05B; H05B47/00; H05B47/20; H05B47/29
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A lighting equipment having automatic lamp substitution comprising; a plurality of light sources, means for leading the light from the plurality of light sources to an appropriate portion, switching means for selectively distributing power to at least one of the plurality of light sources in order to activate it, means for adjusting the volume of said power, detecting and comparing means for distinguishing between failure of the activated light source and the minimum volume of the power to the activated light source so as to detect only failure of the activated light source; and said switching means changes the power supply from the failed light source to at least another one of the plurality of light sources responding to a signal from said detecting means.
Claim 2
Dependent Claim
125 words
A lighting equipment having automatic lamp substitution comprising; a plurality of light sources, means for leading the light from the plurality of light sources to an appropriate portion, switching means for selectively distributing power to at least one of the plurality of light sources in order to activate it, means for adjusting the volume of said power, detecting and comparing means for distinguishing between failure of the activated light source and the minimum volume of the power to the activated light source so as to detect only failure of the activated light source; and said switching means changes the power supply from the failed light source to at least another one of the plurality of light sources responding to a signal from said detecting means.
Claim 3
Dependent Claim
28 words
The lighting equipment of claim 1 wherein; p1 said detecting and comparing means detects the failure of the light source by detecting current flow to the light source.
Claim 4
Dependent Claim
44 words
The lighting equipment having automatic lamp substitution of claim 1 wherein; said detecting and comparing means detects the failure of the light source by detecting current flow of the circuit of said power at least at two positions in the circuit of said power.
Claim 5
Dependent Claim
35 words
The lighting equipment having automatic lamp substitution of claim 1 further including means for turning on any one of the plurality of light sources for predetermined period to check if the light source is operable.
Claim 6
Dependent Claim
17 words
The lighting equipment of claim 1 including means for warning of the failure of the light source.
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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) | 1993-10-01 | 1994-04-02 | 1994-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-01 | 1998-04-02 | 1998-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-01 | 2002-04-02 | 2002-10-02 | $7700.00 | Window Closed / Lapsed |