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US3222835A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prestressed concrete
Assignee: Individual
•
Filing: 1961-05-29
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Granted: 1965-12-14
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Expires: 1981-05-29
Abstract
No abstract record available.
Inventors
- 👤 Gerald C Francis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:48
CPC Classifications
B; B28; B28B; B28B23/00; B28B23/02; B28B23/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
105 words
A METHOD OF PRESTRESSING A CONCRETE SLAB, COMPRISING: LOCATING AN INNER TENSION MEMBER AND A PERIPHERAL COMPRESSION MEMBER ON A COMMON CENTRAL AXIS WITH THE COMPRESSION MEMBER RADIALLY OUTWARDLY SPACED FROM THE TENSION MEMBER, CONNECTING SAID MEMBERS WITH A PLURALITY OF CABLES EXTENDING IN ANNULARLY SPACED RADIAL LINES, IMMOBILIZING ONE OF SAID MEMBERS, ROTATING THE OTHER OF SAID MEMBERS ABOUT SAID COMMON CENTER WHEREBY TO IMPART TENSION LOADING TO SAID CABLES, IMMOBILIZING SAID ROTATED MEMBER, POURING A SLAB OF CONCRETE BETWEEN SAID MEMBERS AND AROUND SAID CABLES, ALLOWING THE CONCRETE TO SET AND THEN RELEASING SAID MEMBERS WHEREBY CABLE STRESSES ARE IMPARTED TO SAID CONCRETE.
Claim 2
Independent Claim
105 words
A METHOD OF PRESTRESSING A CONCRETE SLAB, COMPRISING: LOCATING AN INNER TENSION MEMBER AND A PERIPHERAL COMPRESSION MEMBER ON A COMMON CENTRAL AXIS WITH THE COMPRESSION MEMBER RADIALLY OUTWARDLY SPACED FROM THE TENSION MEMBER, CONNECTING SAID MEMBERS WITH A PLURALITY OF CABLES EXTENDING IN ANNULARLY SPACED RADIAL LINES, IMMOBILIZING ONE OF SAID MEMBERS, ROTATING THE OTHER OF SAID MEMBERS ABOUT SAID COMMON CENTER WHEREBY TO IMPART TENSION LOADING TO SAID CABLES, IMMOBILIZING SAID ROTATED MEMBER, POURING A SLAB OF CONCRETE BETWEEN SAID MEMBERS AND AROUND SAID CABLES, ALLOWING THE CONCRETE TO SET AND THEN RELEASING SAID MEMBERS WHEREBY CABLE STRESSES ARE IMPARTED TO SAID CONCRETE.
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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) | 1968-12-13 | 1969-06-14 | 1969-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-13 | 1973-06-14 | 1973-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-13 | 1977-06-14 | 1977-12-14 | $7700.00 | Window Closed / Lapsed |