Claims
- 1. In a can end having a retained tear strip extending radially from approximately the center of the can end to near the can end rim, said tear strip being defined by a score line of keyhole shape having a rounded portion adjacent the can end rim, and a relatively narrow portion defined by two portions of the score line terminating in spaced relation to each other so as to make said tear strip captive when torn open, said score line becoming shallower as it approaches the end of said portions, and disappearing entirely at the said ends, a pull tab secured to said tear strip by means of a rivet or the like adjacent the rounded end thereof within said score line, and having a nose to initiate a tear along said score line upon lifting of said pull tab, said pull tab, when raised, causing said tear strip to bend downwardly along a transverse line behind said rivet, initiating a tear in said score line and forming a first bend in said tear strip, said pull tab, when retracted, completing the opening of the end and forming a reverse bend in said tear strip adjacent said end, and said pull tab, if desired, when depressed against the top of said can end, causing said first bend to be flattened, and causing said second bend to form a third bend extending below the surface of the can end and having a radius of curvature greater than that of said second bend, said third bend providing a relief for said second bend to prevent breaking of said tear strip when flexed.
- 2. The can end according to claim 1 wherein said relatively narrow portion is defined by two generally parallel portions of the score line.
- 3. The can end according to claim 1 wherein said relatively narrow portion is defined by two portions of the score line skew to each other and forming an acute angle as they progress to the center of said can end.
- 4. The can end according to claim 1 wherein said retracted and depressed pull tab is held in close overlying relationship with said can end.
- 5. The can end according to claim 1 wherein said third bend is formed in said relatively narrow portion of said tear strip.
- 6. The can end according to claim 1 wherein said relatively narrow portion of said tear strip defined by said two portions comprises about 22% of the total length of said tear strip.
- 7. The can end according to claim 1, including means associated with said can end for elevating the pull tab above the surface thereof to facilitate grasping the tab and for masking the opening so formed in the end.
- 8. The can end according to claim 1 wherein said elevated means comprises a raised bead disposed outwardly of the score line along both sides of the tear strip and serving to support the pull tab.
- 9. The can end according to claim 1 wherein said tear strip extends about half way across the can end.
- 10. The can end according to claim 1 wherein said first and second bends are of opposite curvature so that the pull tab may be pressed flat against the can end.
- 11. The can end according to claim 1 wherein said score line is provided with less score residual portions extending from said bend line toward the center of said can end, whereby said pull tab will more easily cam upwardly, relieve the strain on said rivet, and/or reduce the effort required to initially pull said tear strip toward the center of said can end.
- 12. The can end according to claim 11 wherein said score line residual portions extend toward the center of said can end a sufficient distant to assure a weakened area along said score line but not a distance so great as to detrimentally affect the pressure retention capability of the can end.
- 13. The can end according to claim 1 wherein said pull tab is provided with a pair of fulcrum elements, one on each side of the center line of said tear strip, said fulcrum elements being disposed between said bend line and said nose, and serving to pull said tear strip upward behind said rivet and facilitate removal thereof.
- 14. The can end according to claim 13 wherein said fulcrum elements are disposed nearer said bend line than said nose.
- 15. The can end according to claim 13 wherein said fulcrum elements are constituted by off-sets in said pull tab extending outwardly beyond said score line.
- 16. The can end according to claim 13 including means associated with said can end for elevating the pull tab above the surface thereof to facilitate grasping the tab and for masking the opening so formed in the end, said elevated means being interrupted to accommodate said fulcrum elements.
- 17. The can end according to claim 16 wherein said elevated means comprises a raised bead disposed outwardly of the score line along both sides of the tear strip and serving to support the pull tab.
- 18. The can end according to any one of claims 13 through 17 wherein said score line is provided with less score residual portions extending from about said bend line toward the center of said can end, whereby said pull tab will more easily cam upwardly, relieve the strain on said rivet, and/or reduce the effort required to initially pull said tear strip toward the center of said can end.
- 19. The can end according to any one of claims 13 through 17 wherein said score line is provided with less score line residual portion extending from about said bend line toward the center of said can end a sufficient distance to assure a weakened area along said score line, but not a distance so great as to detrimentally affect the pressure retention capability of said can end, whereby said pull tab will more easily cam upwardly, relieve the strain on said rivet, and/or reduce the effort required to initially pull said tear strip toward the center of said can end.
REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 298,924, filed Sept. 3, 1981 in the name of Ralph J. Stolle, entitled "Easy Open Can End Pull Tab Having Retained Tear Strip With Stress Relief Means"; now abandoned.
US Referenced Citations (4)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
298924 |
Sep 1981 |
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