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Patent US2853873A successfully refreshed from Google Patents.
US2853873A
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Field calibrator for combustible gas analyzer
Assignee: MSA Safety Inc
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Filing: 1955-10-14
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Granted: 1958-09-30
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Expires: 1975-10-14
Abstract
No abstract record available.
Inventors
- 👤 Robert C Hollobaugh
- 👤 John P Strange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:24
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/0004; G01N33/0006; H; H04; H04R; H04R3/00; H04R3/002
Claims Analysis
Total Claims: 0
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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) | 1961-09-29 | 1962-03-31 | 1962-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-29 | 1966-03-31 | 1966-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-29 | 1970-03-31 | 1970-09-30 | $7700.00 | Window Closed / Lapsed |