US3900128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Easy open can end resistant to pressure
Assignee: Dayton Reliable Tool and Manufacturing Co
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Filing: 1973-03-30
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Granted: 1975-08-19
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Expires: 1993-03-30
Abstract
Abstract An easy-open can end includes a tear strip defined by a score line which is preferably non-continuous, a pull tab being attached to the tear strip by a rivet such that the free end of the pull tab overlies the score line. A generally triangular depression is positioned in that portion of the tear strip adjacent to the rivet and operates to prevent the can end from assuming a permanently domed configuration in response to pressure within the can, the doming tending to bulge the end of the can causing the free end of the pull tab to rise above the chime. The triangular depression also assists in maintaining the free end of the tab below the chime at moderate residual pressures. In another embodiment, depression ridges are used, adjacent to but spaced from the score line and cooperate with the triangular depression to increase the resistance to permanent deformation of the can end in response to increases in pressure. Blow-off is reduced by increasing score line integrity, as described, which also assures the integrity of any protective coating on the underside of the can end. In one embodiment, the portion of the pull tab overlying the can end in the area of the depression ridges is reduced in crosssection to keep the tab close to the end, which may be enhanced by a tail on the tab which resiliently urges the tab against the end, as described hereafter. A method of forming such a can end is also described.
Inventors
- 👤 Omar L Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:53
CPC Classifications
B; B21; B21D; B21D51/00; B21D51/16; B21D51/38; B21D51/383; B65; B65D; B65D17/00; B65D17/28; B65D17/401; B65D17/4012
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
208 words
An easy-open can end comprising: an end wall surrounded by a peripheral wall which defines the can chime, a score line in said end wall defining a tear strip, teaR strip being in said end wall and including a portion adjacent to said peripheral wall, a tab means including a free end for pulling said tear strip away from said end wall by severing along said score line to form an opening which is larger adjacent said chime than in the center of said end wall, a means affixing said tab means to said tear strip, said free end of said tab means being positioned to overlie at least a portion the score line of said tear strip, means in said tear strip of said can end for preventing said can end from assuming a permanently domed configuration when exposed to pressure from within said can tending to bulge said can end and permanently raising the free end of said tab means above said chime, said means in said tear strip being a depression adjacent to said means for affixing said tab means, and said depression having a depth in the portion thereof adjacent to said affixing means which is greater than the remaining depth of said depression.
Claim 2
Dependent Claim
208 words
An easy-open can end comprising: an end wall surrounded by a peripheral wall which defines the can chime, a score line in said end wall defining a tear strip, teaR strip being in said end wall and including a portion adjacent to said peripheral wall, a tab means including a free end for pulling said tear strip away from said end wall by severing along said score line to form an opening which is larger adjacent said chime than in the center of said end wall, a means affixing said tab means to said tear strip, said free end of said tab means being positioned to overlie at least a portion the score line of said tear strip, means in said tear strip of said can end for preventing said can end from assuming a permanently domed configuration when exposed to pressure from within said can tending to bulge said can end and permanently raising the free end of said tab means above said chime, said means in said tear strip being a depression adjacent to said means for affixing said tab means, and said depression having a depth in the portion thereof adjacent to said affixing means which is greater than the remaining depth of said depression.
Claim 3
Dependent Claim
66 words
The can of claim 1 wherein said depression is generally triangular in shape and of unequal depth, said depression being oriented such that one leg of the triangle is adjacent to said affixing means and the remaining two legs extend away from said affixing means, and the portion of said depression defined by the said one leg being deeper than the remaining portion of said depression.
Claim 4
Dependent Claim
34 words
The can of claim 1 wherein said score line includes predetermined configurations therein for preventing the complete severance of said score line, thereby preventing complete detachment of said tear strip from said end wall.
Claim 5
Dependent Claim
73 words
The can end of claim 1 further including means defining an offset formed within said tear strip, said offset extending substantially perpendicular to the major portion of said tear strip and being positioned immediately adjacent to said score line and defining the means for substantially reducing penetration of a consumer''s skin by the edges of said score line on said tear strip and said end wall when these edges contact the consumer''s skin.
Claim 6
Dependent Claim
29 words
The can end of claim 1 wherein said depression is generally triangular in shape and positioned between said means affixing said tab and the free end of said tab.
Claim 7
Dependent Claim
43 words
The can end of claim 1 wherein said affixing means is positioned between the center of said can and said peripheral wall, and the free end of said tab means being located between the center of said can end and said peripheral wall.
Claim 8
Dependent Claim
18 words
The can end of claim 1 further including depression ridges adjacent to but spaced from said score line.
Claim 9
Dependent Claim
53 words
The can end of claim wherein said tab means includes a tail extending inwardly of said tab means, said affixing means being a rivet intergral with said can end and affixed to said tail and said tail being inclined toward said can end to maintain said tab resiliently urged toward said can end.
Claim 10
Dependent Claim
17 words
The can end of claim 7 wherein said depression ridges include bottom portions which are essentially flat.
Claim 11
Dependent Claim
20 words
The can end of claim 1 wherein said tear strip includes means to prevent complete severance of said score line.
Claim 12
Dependent Claim
29 words
The can end of claim 1 further including means forming a ledge intermediate the end wall and the tear strip, and said score line being located on said ledge.
Claim 13
Dependent Claim
65 words
The can end of claim 1 further including means forming a ledge intermediate the end wall and the tear strip, said ledge being continuous and including a pair of reversing curves, each of said reversing curves terminating in a second reversing curve, and the portion of said ledge between said second reversing curves forming V-shaped curve, the apex of which is directed toward said tab.
Claim 14
Dependent Claim
31 words
The can end of claim 12 wherein said score line is located on said ledge and terminates short of said second reversing curve to prevent complete severance of said tear strip.
Claim 15
Dependent Claim
22 words
The can end of claim 12 wherein the portion of said ledge adjaCent to said score line is of reduced cross-sectional thickness.
Claim 16
Dependent Claim
25 words
The can end of claim 12 further including means forming a depression between the apex of said V-shaped curve and the chime of said can.
Claim 17
Dependent Claim
19 words
The can end of claim 13 further including means forming depression ridges adjacent to but spaced from said ledge.
Claim 18
Dependent Claim
64 words
The can end of claim 16 wherein said tab overlies a portion of said depression ridges and the portion of said can end between said ledge and the depression ridges, and the portion of said tab overlying the portion of said can end between said ledge and depression ridges being flattened to maintain the free end of said tab close to said can end.
Claim 19
Dependent Claim
205 words
An easy-open can end comprising an end wall and a chime, a tear strip in said wall, a score line in said end wall defining said tear strip, tab means attached to said tear strip and having a free end extending toward the center of the can end, said score line having force reversing curves formed therein to prevent complete removal of said tear strip from said end wall when said score line is severed, means in said tear strip closely adjacent to said score line for preventing penetration of user''s skin by the edge of said score line remaining on said tear strip when said score line is severed by pulling said tear strip away from said end wall, means in said tear strip of said can end for preventing the free end of said tab means from extending above said chime in response to pressure within said can tending to bulge said end wall, said means in said tear strip being a depression adjacent to the location of attachment to said tab means, and said depression having a depth in the portion thereof adjacent to the location of attachment to said tab means which is greater than the remaining depth of said depression.
Claim 20
Dependent Claim
205 words
An easy-open can end comprising an end wall and a chime, a tear strip in said wall, a score line in said end wall defining said tear strip, tab means attached to said tear strip and having a free end extending toward the center of the can end, said score line having force reversing curves formed therein to prevent complete removal of said tear strip from said end wall when said score line is severed, means in said tear strip closely adjacent to said score line for preventing penetration of user''s skin by the edge of said score line remaining on said tear strip when said score line is severed by pulling said tear strip away from said end wall, means in said tear strip of said can end for preventing the free end of said tab means from extending above said chime in response to pressure within said can tending to bulge said end wall, said means in said tear strip being a depression adjacent to the location of attachment to said tab means, and said depression having a depth in the portion thereof adjacent to the location of attachment to said tab means which is greater than the remaining depth of said depression.
Claim 21
Dependent Claim
22 words
The can end of claim 18 wherein said means in said can end further includes depression ridges adjacent to said score line.
Claim 22
Dependent Claim
14 words
The can end of claim 18 wherein said depression is generally triangular in shape.
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) | 1978-08-18 | 1979-02-17 | 1979-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-18 | 1983-02-17 | 1983-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-18 | 1987-02-17 | 1987-08-19 | $7700.00 | Window Closed / Lapsed |