US3710161A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Quick-heating impregnated planar cathode
Assignee: General Electric Co
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Filing: 1970-10-30
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Granted: 1973-01-09
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Expires: 1990-10-30
Abstract
Abstract A quick-heating planar cathode employs a disk of fine mesh wire of refractory metal around which is bonded or sintered a porous layer of tungsten particles impregnated with electron-emissive material, a layer of inorganic insulation covering one surface of the porous cathode, and a heater on the insulating surface.
Inventors
- 👤 J Beggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:30
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/28; H01J1/14
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
40 words
The cathode of claim 1 in which the wire comprises a metal selected from the group consisting of molybdenum, tungsten, an alloy of molybdenum and rhenium, and an alloy of tungsten and rhenium and the inorganic insulation comprises boron nitride.
Claim 2
Dependent Claim
17 words
The cathode of claim 2 in which the wire consists of an alloy of molybdenum and rhenium.
Claim 3
Dependent Claim
17 words
The cathode of claim 2 in which the wire consists of an alloy of tungsten and rhenium.
Claim 4
Dependent Claim
24 words
The cathode of claim 1 in which a thin layer of metal is positioned between the layer of inorganic insulation and the tungsten particles.
Claim 5
Dependent Claim
12 words
The cathode of claim 5 in which said metal layer comprises molybdenum.
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) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |