US3621322A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-pressure compact arc lamp with electrodes containing tantalum carbide
Assignee: Osram GmbH
•
Filing: 1969-09-02
•
Granted: 1971-11-16
•
Expires: 1989-09-02
Abstract
Abstract A high-pressure compact arc lamp with an envelope which is substantially spherically bulbous where the discharge occurs, and having opposed aligned electrodes therein spaced from each other a distance less than the distance of the bulb wall therefrom at a plane transverse to and between the ends of said electrodes, both of the electrodes comprising sintered bodies composed of from 20 to 90 percent by weight of tantalum carbide and from 80 to 10 percent by weight of at least one metal from the group of tungsten, rhenium, molybdenum and tantalum.
Inventors
- 👤 Manfred Rehmet
- 👤 Jurgen Begemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:01
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/04; H01J61/06; H01J61/073; H01J61/0735
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
31 words
A lamp in accordance with claim 1, wherein said bulbous portion of the envelope contains mercury vaporized in operation of the lamp and producing pressure from 10 up to 100 atmospheres.
Claim 2
Dependent Claim
23 words
A lamp in accordance with claim 1, wherein the bulbous portion of the envelope contains a metal halide for supplying gas filling therefor.
Claim 3
Dependent Claim
33 words
A lamp in accordance with claim 1, wherein said sintered bodies constituting the electrodes are composed of approximately 60 percent by weight of tantalum carbide and approximately 40 percent by weight of tungsten.
Claim 4
Dependent Claim
34 words
A lamp in accordance with claim 1, wherein the dimensions of the electrode bodies and the power input are so coordinated that in the region where the arc strikes a small fusing area forms.
Claim 5
Dependent Claim
29 words
A lamp in accordance with claim 1, wherein said electrodes have cylindrical ends most proximate to said supports and have their other ends tapered where directed toward each other.
Claim 6
Dependent Claim
29 words
A lamp in accordance with claim 1, wherein electrode coils are located on said supports behind said electrode bodies, said electrode coils having an emitter carried between convolutions thereof.
Claim 7
Dependent Claim
29 words
A lamp in accordance with claim 7, wherein a gettering coil of tantalum is provided on one of said supports behind the respective sintered electrode body on that support.
References Cited (Backward Citations)
US2304412A
Cited
US2965790A
Cited
US2697183A
Cited
US2682007A
Cited
US2720474A
Cited
US2896107A
Cited
US3061756A
Cited
US3168668A
Cited
US3232717A
Cited
US3405328A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |