US4217989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tamper-proof closure
Assignee: Silgan Containers LLC
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Filing: 1978-12-01
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Granted: 1980-08-19
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Expires: 1998-12-01
Abstract
Abstract A new tamper-proof closure includes a cap having a plurality of circumferentially spaced slits separated by bridges with a plurality of lines of weakness extending perpendicular to the slits and aligned with the respective bridges. The lines of weakness have a residual thickness which varies between opposite ends.
Inventors
- 👤 Robert W. George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:11
CPC Classifications
B; B23; B23D; B23D31/00; B23D31/001; B21; B21D; B21D51/00; B21D51/16; B21D51/38; B21D51/44; B21D51/50; B65; B65D; B65D41/00; B65D41/32; B65D41/34; B65D41/348; B65D2401/00; B65D2401/15; B65D2401/35
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
74 words
A tamper-proof closure having a substantially flat top and a generally cylindrical skirt extending from the perimeter of said substantially flat top with said skirt having a free edge, a plurality of circumferentially spaced lines of weakness extending generally parallel to the axis of said skirt, each of said lines of weakness having a thickness at its end closest to said free edge which is greater than the thickness at an opposite end thereof.
Claim 2
Dependent Claim
74 words
A tamper-proof closure having a substantially flat top and a generally cylindrical skirt extending from the perimeter of said substantially flat top with said skirt having a free edge, a plurality of circumferentially spaced lines of weakness extending generally parallel to the axis of said skirt, each of said lines of weakness having a thickness at its end closest to said free edge which is greater than the thickness at an opposite end thereof.
Claim 3
Dependent Claim
52 words
A tamper-proof closure as defined in claim 1, in which each line of weakness has a portion adjacent said free end which is equal to the thickness of said cylindrical skirt and the remainder of each line of weakness has a constant thickness substantially less than the thickness of said cylindrical skirt.
Claim 4
Dependent Claim
33 words
A tamper-proof closure as defined in claim 2, in which said portion of each line of weakness has a dimension axially of said skirt which is greater than the thickness of said skirt.
Claim 5
Dependent Claim
26 words
A tamper-proof closure as defined in claim 1, in which each line of weakness has a constantly reducing thickness from said end to said opposite end.
Claim 6
Dependent Claim
23 words
A tamper-proof closure as defined in claim 1, in which each line of weakness includes a slot in said skirt free edge end.
Claim 7
Dependent Claim
86 words
A tamper-proof metal closure including a circular top wall and a generally cylindrical side wall extending from the periphery of said top wall and terminating in a free edge with a plurality of circumferentially spaced slits extending perpendicular to the axis of said side wall at a location to define a band, and a plurality of lines of weakness extending axially in said band, each of said lines of weakness having a maximum thickness at said free edge and a minimum thickness at the opposite end.
Claim 8
Dependent Claim
86 words
A tamper-proof metal closure including a circular top wall and a generally cylindrical side wall extending from the periphery of said top wall and terminating in a free edge with a plurality of circumferentially spaced slits extending perpendicular to the axis of said side wall at a location to define a band, and a plurality of lines of weakness extending axially in said band, each of said lines of weakness having a maximum thickness at said free edge and a minimum thickness at the opposite end.
Claim 9
Dependent Claim
23 words
A closure as defined in claim 6, in which each of said lines of weakness has an unscored portion at said free edge.
Claim 10
Dependent Claim
34 words
A closure as defined in claim 7, in which the remainder of each of said lines of weakness has a substantially constant thickness which is substantially less than the thickness of said side wall.
References Cited (Backward Citations)
US3861551A
Cited
US3837519A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-19 | 1984-02-18 | 1984-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-19 | 1988-02-18 | 1988-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-19 | 1992-02-18 | 1992-08-19 | $7700.00 | Window Closed / Lapsed |