Patent US3290840A successfully refreshed from Google Patents.
US3290840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and means for chemically prestressing concrete
Assignee: Prescon Corp
•
Filing: 1962-07-20
•
Granted: 1966-12-13
•
Expires: 1982-07-20
Abstract
No abstract record available.
Inventors
- 👤 Karl H Middendorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:16
CPC Classifications
E; E04; E04G; E04G21/00; E04G21/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
IN A CONCRETE STRUCTURE, A BODY PORTION OF CHEMICALLY EXPANDED CONCRETE AND MEANS FOR PUTTING SAID BODYPORTION UNDER COMPRESSION COMPRISING SPACED FLAT FACED BEARING PLATES EMBEDDED IN SAID BODY PORTION IN SPACED RELATION TO EACH OTHER, A SMOOTH SURFACED HIGH TENSILE STRENGTH STEEL TENSION MEMBER HAVING A LUBRICATING COAT ING THEREON EMBEDDED IN SAID BODY PORITION AND EXTENDING BETWEEN SAID BEARING PLATES, SAID BEARING PLATES HAVING OPENINGS THEREIN THROUGH WHICH SAID TENSION MEMBER EXTENDS, SAID TENSION MEMBER HAVING AN ENLARGEMENT THEREON AT EACH END THEREOF AND MEANS SECURING SAID ENLARGEMENTS SNUGLY IN FIXED POSITION TO THE SIDES OF SAID
Claim 2
Dependent Claim
99 words
IN A CONCRETE STRUCTURE, A BODY PORTION OF CHEMICALLY EXPANDED CONCRETE AND MEANS FOR PUTTING SAID BODYPORTION UNDER COMPRESSION COMPRISING SPACED FLAT FACED BEARING PLATES EMBEDDED IN SAID BODY PORTION IN SPACED RELATION TO EACH OTHER, A SMOOTH SURFACED HIGH TENSILE STRENGTH STEEL TENSION MEMBER HAVING A LUBRICATING COAT ING THEREON EMBEDDED IN SAID BODY PORITION AND EXTENDING BETWEEN SAID BEARING PLATES, SAID BEARING PLATES HAVING OPENINGS THEREIN THROUGH WHICH SAID TENSION MEMBER EXTENDS, SAID TENSION MEMBER HAVING AN ENLARGEMENT THEREON AT EACH END THEREOF AND MEANS SECURING SAID ENLARGEMENTS SNUGLY IN FIXED POSITION TO THE SIDES OF SAID
References Cited (Backward Citations)
US724500A
Cited
US2376414A
Cited
US2522116A
Cited
GB665855A
Cited
US2683915A
Cited
GB660438A
Cited
GB694596A
Cited
US2827770A
Cited
GB721198A
Cited
US2755657A
Cited
US2948995A
Cited
US2941394A
Cited
US3066581A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-12-12 | 1970-06-13 | 1970-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-12 | 1974-06-13 | 1974-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-12 | 1978-06-13 | 1978-12-13 | $7700.00 | Window Closed / Lapsed |