US3619683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arc tubes
Assignee: British Lighting Industries Ltd
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Filing: 1969-05-23
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Granted: 1971-11-09
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Expires: 1989-05-23
Abstract
Abstract A high-pressure mercury vapor lamp with a fused silica pinch sealed arc tube containing metallic additions in halide form is provided with ceramic screens mounted on the pinch seals to cover parts of the envelope of the tube behind the electrodes to reduce the heat loss from these parts.
Inventors
- 👤 Robert Frederick Weston
- 👤 Kenneth Frederick Furmidge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:09
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/52; H01J61/523
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
122 words
A sealed vapor-filled arc tube, having end portions, comprising: pinch seals, having parallel edges, sealing each end portion of said arc tube; lead assemblies sealed through said pinch seals; arc-sustaining electrodes in said arc tube, said electrodes being supported in said arc tube by said lead assemblies; ceramic shields disposed about and spaced from said end portions and supported from and held in contact with said pinch seals, said parallel edges of said pinch seals being substantially uncovered by said ceramic shields, each ceramic shield comprising two separate ceramic pieces mounted opposite each other, whereby heat loss from the end portions of said arc tube during operation is reduced and cooling of the pinch seals occurs through the uncovered parallel edges thereof.
Claim 2
Dependent Claim
122 words
A sealed vapor-filled arc tube, having end portions, comprising: pinch seals, having parallel edges, sealing each end portion of said arc tube; lead assemblies sealed through said pinch seals; arc-sustaining electrodes in said arc tube, said electrodes being supported in said arc tube by said lead assemblies; ceramic shields disposed about and spaced from said end portions and supported from and held in contact with said pinch seals, said parallel edges of said pinch seals being substantially uncovered by said ceramic shields, each ceramic shield comprising two separate ceramic pieces mounted opposite each other, whereby heat loss from the end portions of said arc tube during operation is reduced and cooling of the pinch seals occurs through the uncovered parallel edges thereof.
Claim 3
Dependent Claim
20 words
The arc tube of claim 1 including a resilient holding means for holding said two separate ceramic pieces in position.
Claim 4
Dependent Claim
12 words
The arc tube of claim 1 containing metallic additions in halide form.
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) | 1974-11-08 | 1975-05-10 | 1975-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-08 | 1979-05-10 | 1979-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-08 | 1983-05-10 | 1983-11-09 | $7700.00 | Window Closed / Lapsed |