Patent US3173443A successfully refreshed from Google Patents.
US2848635A
Expired / Lapsed
US
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Ionization gauges
Assignee: Vacuum Electronic Engineering Co
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Filing: 1954-11-16
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Granted: 1958-08-19
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Expires: 1974-11-16
Abstract
No abstract record available.
Inventors
- 👤 Raible Frank
- 👤 Peters John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:45
CPC Classifications
H; H01; H01J; H01J41/00; H01J41/02; H01J41/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
AN IONIZATION GAUGE FOR MEASURING GAS PRESSURES COMPRISING AN ENVELOPE, A HELICAL POSITIVE GRID ELECTRODE POSITIONED WITHIN SAID ENVELOP, A NEGATIVE RECTILINEAR WIRE COLLECTOR ELECTRODE LOCATED AXIALLY WITHIN SAID POSITIVE ELECTRODE, AND ELECTRON EMISSIVE MEANS POSITION ADJACENT SAID POSITIVE ELECTRODE, SAID MEANS COMPRISING A FILAMENT BASE SELECTED FROM THE GROUP CONSISTING OF IRIDIUM, RHODIUM AND PLATINUM-IRIDIUM ALLOY AND BEING UNAFFECTED BY EXPOSURE TO ATMOSPHERIC PRESSURE AND ELEVATED TEMPERATURE AND A COATING OF ELECTRON EMISSIVE MATERIAL SELECTED FROM THE GROUP CONSISTING OF THORIUM
Claim 2
Dependent Claim
82 words
AN IONIZATION GAUGE FOR MEASURING GAS PRESSURES COMPRISING AN ENVELOPE, A HELICAL POSITIVE GRID ELECTRODE POSITIONED WITHIN SAID ENVELOP, A NEGATIVE RECTILINEAR WIRE COLLECTOR ELECTRODE LOCATED AXIALLY WITHIN SAID POSITIVE ELECTRODE, AND ELECTRON EMISSIVE MEANS POSITION ADJACENT SAID POSITIVE ELECTRODE, SAID MEANS COMPRISING A FILAMENT BASE SELECTED FROM THE GROUP CONSISTING OF IRIDIUM, RHODIUM AND PLATINUM-IRIDIUM ALLOY AND BEING UNAFFECTED BY EXPOSURE TO ATMOSPHERIC PRESSURE AND ELEVATED TEMPERATURE AND A COATING OF ELECTRON EMISSIVE MATERIAL SELECTED FROM THE GROUP CONSISTING OF THORIUM
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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) | 1961-08-18 | 1962-02-17 | 1962-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-08-18 | 1966-02-17 | 1966-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-08-18 | 1970-02-17 | 1970-08-19 | $7700.00 | Window Closed / Lapsed |