US4349116A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic screw-threaded closure cap
Assignee: Crown Cork and Seal Co Inc
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Filing: 1979-07-25
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Granted: 1982-09-14
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Expires: 1999-07-25
Abstract
Abstract A thermoplastic cap having improved anti-backoff characteristics features a primary helical thread and a coaxial secondary thread. The cap is of a thermoplastic material having an elastic modulus in flexure within the range of from about 0.2×10 5 to about 10 6 pounds per square inch so that the secondary helical thread will flex in response to tightening torque.
Inventors
- 👤 Werner R. Luenser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:38
CPC Classifications
B; B65; B65D; B65D41/00; B65D41/02; B65D41/04; B65D41/0471; B65D41/0407; B65D41/0428
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
139 words
A thermoplastic cap having an elastic modulus in flexure within the range of from about 0.2×10 5 to about 10 6 pounds per square inch and comprising: a. a top wall; b. an annular sidewall integrally formed with and downwardly depending from the top wall; c. an inwardly extending primary helical thread about the inside surface of said sidewall for cooperation with a container helical thread; and d. an inwardly extending secondary helical thread i. about the inside surface of said sidewall, ii. coaxial with said primary thread, iii. displaced upwardly within the range of from about 0.010 to about 0.030 inches above said primary thread, iv. having a vertical width within the range of from about 0.010 to about 0.030 inches, and v. having a horizontal width within the range of from about 0.015 to about 0.035 inches.
Claim 2
Dependent Claim
139 words
A thermoplastic cap having an elastic modulus in flexure within the range of from about 0.2×10 5 to about 10 6 pounds per square inch and comprising: a. a top wall; b. an annular sidewall integrally formed with and downwardly depending from the top wall; c. an inwardly extending primary helical thread about the inside surface of said sidewall for cooperation with a container helical thread; and d. an inwardly extending secondary helical thread i. about the inside surface of said sidewall, ii. coaxial with said primary thread, iii. displaced upwardly within the range of from about 0.010 to about 0.030 inches above said primary thread, iv. having a vertical width within the range of from about 0.010 to about 0.030 inches, and v. having a horizontal width within the range of from about 0.015 to about 0.035 inches.
Claim 3
Dependent Claim
11 words
The cap of claim 1 wherein said top wall is circular.
Claim 4
Dependent Claim
28 words
The cap of claim 1 wherein said elastic modulus in flexure is within the range of from about 1×10 5 to about 5×10 5 pounds per square inch.
Claim 5
Dependent Claim
11 words
The cap of claim 1 wherein said cap is of polypropylene.
Claim 6
Dependent Claim
38 words
The cap of claim 4 wherein said vertical width is within the range of from about 0.015 to about 0.020 inches, and wherein said horizontal width is within the range of from about 0.020 to about 0.025 inches.
Claim 7
Dependent Claim
11 words
The cap of claim 1 wherein said cap is of polyethylene.
Claim 8
Dependent Claim
38 words
The cap of claim 6 wherein said vertical width is within the range of from about 0.015 to about 0.020 inches, and wherein said horizontal width is within the range of from about 0.020 to about 0.025 inches.
Claim 9
Dependent Claim
125 words
A thermoplastic cap comprising: a. a top wall; b. an annular sidewall integrally formed and downwardly depending from said top wall; c. an inwardly extending primary helical thread about the inside surface of said sidewall for cooperation with a container helical thread; and d. an inwardly extending secondary helical thread, i. about the inside surface of said sidewall, ii. coaxial with said primary thread, iii. having a horizontal and vertical width less than the horizontal and vertical width of said primary thread, iv. displaced upwardly above said primary thread whereby said secondary thread comes into resilient engagement with the underside of the container helical thread when said cap is screwed to the container, said engagement affecting resistance to loosening of the cap from the container.
Claim 10
Dependent Claim
125 words
A thermoplastic cap comprising: a. a top wall; b. an annular sidewall integrally formed and downwardly depending from said top wall; c. an inwardly extending primary helical thread about the inside surface of said sidewall for cooperation with a container helical thread; and d. an inwardly extending secondary helical thread, i. about the inside surface of said sidewall, ii. coaxial with said primary thread, iii. having a horizontal and vertical width less than the horizontal and vertical width of said primary thread, iv. displaced upwardly above said primary thread whereby said secondary thread comes into resilient engagement with the underside of the container helical thread when said cap is screwed to the container, said engagement affecting resistance to loosening of the cap from the container.
Claim 11
Dependent Claim
11 words
The cap of claim 8 wherein said top wall is circular.
Claim 12
Dependent Claim
30 words
The cap of claim 8 wherein said cap has an elastic modulus in flexure within a range of from about 0.2×10 5 to about 0.2×10 6 pounds per square inch.
Claim 13
Dependent Claim
28 words
The cap of claim 10 wherein said elastic modulus in flexure is within the range of from about 1×10 5 to about 5×10 5 pounds per square inch.
Claim 14
Dependent Claim
10 words
The cap of claim 8 wherein said cap is polypropylene.
Claim 15
Dependent Claim
10 words
The cap of claim 8 wherein said cap is polyethylene.
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) | 1985-09-13 | 1986-03-15 | 1986-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-13 | 1990-03-15 | 1990-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-13 | 1994-03-15 | 1994-09-14 | $7700.00 | Window Closed / Lapsed |