US3959682A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric lamp
Assignee: US Philips Corp
•
Filing: 1975-02-27
•
Granted: 1976-05-25
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Expires: 1995-02-27
Abstract
Abstract Electric lamp having a hermetically sealed gas-filled hard-glass or vitreous-silica lamp envelope provided with a current lead-in which is sealed into a portion of the lamp envelope and comprises a foil mainly consisting of molybdenum and a current supply lead mainly consisting of tungsten which is secured to the foil by a welded joint and extends into the lamp envelope. The welded joint contains iron or an alloy of at least 50% by weight of iron and one or more of the elements scandium, titanium, vanadium, chromium, manganese, cobalt, nickel and copper as the welding agent.
Inventors
- 👤 Gustaaf Adolf Wesselink
- 👤 Arie Koelewijn
- 👤 Hendrik Roelofs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:12
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/36; H01J61/366; H01J61/368; H01J5/00; H01J5/32; H01J5/34
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
99 words
Electric lamp having a hermetically sealed gas-filled hard-glass or vitreous-silica lamp envelope provided with a current lead-in which is sealed into a portion of the lamp envelope and comprises a foil mainly consisting of molybdenum and a current supply lead mainly consisting of tungsten which is secured to the foil by a welded joint and extends into the lamp envelope, characterized in that the welded joint contains iron or an alloy of at least 50% by weight of iron and one or more of the elements scandium, titanium, vanadium chromium, manganese, cobalt, nickel and copper as the welding agent.
Claim 2
Dependent Claim
99 words
Electric lamp having a hermetically sealed gas-filled hard-glass or vitreous-silica lamp envelope provided with a current lead-in which is sealed into a portion of the lamp envelope and comprises a foil mainly consisting of molybdenum and a current supply lead mainly consisting of tungsten which is secured to the foil by a welded joint and extends into the lamp envelope, characterized in that the welded joint contains iron or an alloy of at least 50% by weight of iron and one or more of the elements scandium, titanium, vanadium chromium, manganese, cobalt, nickel and copper as the welding agent.
Claim 3
Dependent Claim
16 words
Electric lamp as claimed in claim 1, characterized in that the welding agent is stainless steel.
Claim 4
Dependent Claim
28 words
Electric lamp as claimed in claim 2, characterized in that the current lead-in is sealed in a portion of the lamp envelope in the form of a pinch.
Claim 5
Dependent Claim
43 words
Gas discharge lamp as claimed in claim 3 provided with at least two electrodes which are disposed within the lamp envelope and each are secured to a current supply lead and between which the discharge is maintained in the operation of the lamp.
Claim 6
Dependent Claim
23 words
Gas discharge lamp as claimed in claim 4 in which the gas-filling contains at least one of the elements mercury, zinc and cadmium.
Claim 7
Dependent Claim
51 words
High pressure mercury-vapour discharge lamp as claimed in claim 5, in which the gas-filling contains, in addition to mercury and cadmium and/or zinc, a calcium halide and a sodium halide and a halide of at least one of the elements lithium, thallium, indium, scandium, yttrium, lanthanum and the rare earth metals.
References Cited (Backward Citations)
US3582704A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-25 | 1979-11-24 | 1980-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-25 | 1983-11-24 | 1984-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-25 | 1987-11-24 | 1988-05-25 | $7700.00 | Window Closed / Lapsed |