Patent US3138878A successfully refreshed from Google Patents.
US3138878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spirit level
Assignee: Individual
•
Filing: 1961-06-26
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Granted: 1964-06-30
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Expires: 1981-06-26
Abstract
No abstract record available.
Inventors
- 👤 Ralph E Mehlman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:32
CPC Classifications
G; G01; G01C; G01C9/00; G01C9/18; G01C9/24; G01C9/34
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
63 words
STRUCTURE SUBSTANTIALLY AS DISCLOSED AND DESCRIBED COMPRISING A SEALED TUBE HAVING A UNIFORM NON-CIRCULAR CROSS-SECTIONAL SHAPE IN A PLANE PERPENDICULAR TO ITS LONGITUDINAL AXIS, SAID UNIFORM CROSS-SECTION DEFINED BY A BOTTOM PORTION THAT IS GENERALLY CIRCULAR AND WHICH APEXES INTO AN UPPER GENERALLY CIRCULAR PORTION, SAID UPPER PORTION HAVING A SMALLER SECTIONAL AREA THAN SAID BOTTOM PORTION, SAID UPPER PORTION HAVING GRADUATIONS THEREON.
Claim 2
Dependent Claim
63 words
STRUCTURE SUBSTANTIALLY AS DISCLOSED AND DESCRIBED COMPRISING A SEALED TUBE HAVING A UNIFORM NON-CIRCULAR CROSS-SECTIONAL SHAPE IN A PLANE PERPENDICULAR TO ITS LONGITUDINAL AXIS, SAID UNIFORM CROSS-SECTION DEFINED BY A BOTTOM PORTION THAT IS GENERALLY CIRCULAR AND WHICH APEXES INTO AN UPPER GENERALLY CIRCULAR PORTION, SAID UPPER PORTION HAVING A SMALLER SECTIONAL AREA THAN SAID BOTTOM PORTION, SAID UPPER PORTION HAVING GRADUATIONS THEREON.
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) | 1967-06-30 | 1967-12-30 | 1968-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-30 | 1971-12-30 | 1972-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-30 | 1975-12-30 | 1976-06-30 | $7700.00 | Window Closed / Lapsed |