US3889916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastic threaded insert for forming voids in concrete products
Assignee: FOSROC Inc
•
Filing: 1973-03-26
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Granted: 1975-06-17
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Expires: 1993-03-26
Abstract
Abstract A protective plug for a concrete coil insert or the like. The plug consists of a monolithic plastic unit including a tapered head and a threaded cylindrical portion extending therefrom in concentric relationship thereto. The head is hollow and has a wall extending diametrally thereacross. The unit is intended to be inserted into a coil insert which is retained within a casting of concrete. The protective plug is nailed or otherwise fastened to a wooden form in which the concrete is to be poured and the coil insert is threaded thereupon. After the concrete is cast, the concrete unit is removed from the form and the protective plug is unscrewed from the coil insert.
Inventors
- 👤 Robert John Ilukowicz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:29
CPC Classifications
B; B29; B29D; B29D1/00; Y; Y10; Y10S; Y10S411/00; Y10S411/904; Y10S411/908
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
58 words
A PROTECTIVE PLUG FOR A CONCRETE COIL INSERT OR THE LIKE, SAID PLUG COMPRISING A MONOLITHIC PLASTIC UNIT INCLUDING A TAPERED HEAD IN THE SHAPE OF A TRUNCATED CONICAL FORM AND A THREADED CYLINDRICAL PORTION EXTENDING THEREFROM IN CONCENTRIC RELATION THERETO, SAID PLASTIC BEING A HIGH DENSITY POLYETHYLENE WITH A DENSITY OF-ABOUT 0.94 TO 0.97, SAID HEAD BEING
Claim 2
Dependent Claim
58 words
A PROTECTIVE PLUG FOR A CONCRETE COIL INSERT OR THE LIKE, SAID PLUG COMPRISING A MONOLITHIC PLASTIC UNIT INCLUDING A TAPERED HEAD IN THE SHAPE OF A TRUNCATED CONICAL FORM AND A THREADED CYLINDRICAL PORTION EXTENDING THEREFROM IN CONCENTRIC RELATION THERETO, SAID PLASTIC BEING A HIGH DENSITY POLYETHYLENE WITH A DENSITY OF-ABOUT 0.94 TO 0.97, SAID HEAD BEING
Claim 3
Dependent Claim
29 words
A plug as claimed in claim 1 wherein said head is at least about one-half inch in thickness and has a taper towards said cylindrical portion of about 15*-30*.
Claim 4
Dependent Claim
30 words
A plug as claimed in claim 2 wherein said cylindrical portion is at least about three inches in length and is threaded along at least substantially the entire extent thereof.
Claim 5
Dependent Claim
20 words
A plug as claimed in claim 3 wherein said portion has a thread of about 4 1/2 turns per inch.
Claim 6
Dependent Claim
30 words
A plug as claimed in claim 4 wherein said thread has a maximum diameter of about 3/4 of an inch and a minimum diameter of about 5/8 of an inch.
Claim 7
Dependent Claim
30 words
A plug as claimed in claim 3 wherein said cylindrical portion has a thread formed of a particular recess having a radius of about 1/16 to 1/8 of an inch.
Claim 8
Dependent Claim
18 words
A plug as claimed in claim 6 wherein the recess is about 40* - 70* of a circle.
Claim 9
Dependent Claim
18 words
A plug as claimed in claim 7 wherein the recess is about 50* - 60* of a circle.
References Cited (Backward Citations)
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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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |