Claims
- 1. A method of making a double fold in sheet material, which double fold is formed on the center panel of an easy opening container and which panel with the double fold thereon is removed by rupture of a scoreline, comprising:
- providing a piece of sheet material having first and second axially offset radial sections integrally joined by a connecting wall;
- said first radial section being vertically above said second section;
- expansion bead means located radially inwardly of said second radial section
- collapsing said expansion bead whereby said first and second radial sections and said connecting wall are formed to a configuration which is generally Z-shaped in cross-section with the first and second sections forming the top and bottom legs of said Z respectively, and the connecting wall forming the connecting leg thereof,
- providing first and second tools, said second tool having a recess therein;
- relatively positioning the tools and the sheet material so that the tools are on opposite sides of the radial sections and said recess confronts the second radial section adjacent the connecting wall; and
- applying an axial compressive force to said radial sections with said tools to collapse said connecting wall thereby to form a first fold between the connecting wall and the first radial section and a second fold between the connecting wall and the second radial section with the connecting wall connecting said folds and to force at least a portion of the second fold into said recess whereby the connecting wall is spaced from at least a portion of said first radial section.
- 2. A method of making an easy opening container wall comprising:
- providing a piece of sheet material having first and second axially offset radial sections integrally joined by a generally axial connecting wall and with said second radial section having a rib formed thereon adjacent said connecting wall;
- scoring said first radial section to define a panel at least partially removable from the piece of sheet material with the line of score being adjacent the connecting wall;
- applying an axially directed compressive force to said rib to reduce the axial dimension of the rib and radially spread the rib to thereby tend to incline the connecting wall in a direction so that it extends outwardly as it projects axially inwardly whereby said connecting wall forms with said first and second radial sections a generally Z-shaped cross-section with the first and second sections forming the top and bottom legs of said Z, respectively, and the connecting wall forming the connecting leg thereof;
- applying an axial compressive force to said radial sections to thereby at least substantially collapse said connecting wall and to form a first fold between the connecting wall and the first radial section and a second fold between the connecting wall and said second radial section with said connecting wall connecting said sections;
- providing a space forming a recess along at least a region of the second radial section adjacent the connecting wall and on the side of the second radial section remote from the first radial section during said step of applying so that the portion of said second fold containing said region is urged into said recess during said step of applying and the connecting wall is spaced from said first radial section adjacent said region; and
- attaching a tab to the panel whereby said panel can be at least partially removed from the piece of sheet material.
- 3. A method as defined in claim 2 wherein said rib is completely flattened during said step of applying an axially directed compressive force to said rib.
- 4. A method of forming an end structure for a container wherein an end blank is successively formed into an end structure which includes an integrally formed rivet for securing a tab to a central panel, a scoreline rupturable to form an opening in the central panel and protective fold means which extends radially outwardly of the scoreline, comprising the steps of:
- providing an end blank which includes an attaching flange for connecting the end structure to the wall of a container, the flange peripherally extending around said blank and spaced radially outwardly and vertically above the central panel, said flange being connected to said central panel by a wall portion including first and second axially spaced wall segments, the first of said segments being axially spaced above a second wall segment and joined thereto by a connecting wall thereby forming a first pivot region at the upper end of the connecting wall segment and a second pivot region at the lower end of the connecting wall segment,
- reforming said end blank with a cooperative die and punch assembly to move said pivot regions relative to each other while forming the scoreline in said first wall segment thereby so reforming the first wall segment such that the latter extends radially of the first pivot region to position the second pivot region radially outward of the first, the first pivot region extending radially inwardly of the second pivot region and being interconnected therewith through the connecting wall segment, the first and second wall segments and said connecting wall segment being generally Z-shaped in cross-section with the first and second wall segments forming the top and bottom legs of said Z, respectively, and the connecting wall forming the connecting leg thereof, the first and second pivot regions defining the portions of the end structure which form the folds of the protective fold means; and
- axially advancing one of the said first and second wall segments toward the other to axially collapse said connecting wall segment whereby said first pivot region is radially inward of said second pivot region and said scoreline is radially inward of said second pivot region, the line of score defining a segment of said central panel removable therefrom by rupture of said scoreline.
- 5. A method as set forth in claim 4 wherein during said reforming step includes moving said second pivot region radially outwardly of said first pivot region.
- 6. A method as set forth in claim 4 wherein said reforming step includes moving said second pivot region radially outwardly of the first pivot region and wherein said step of axially advancing said first and second wall segments includes the use of a first and second tools, said second tool having a recess therein, said tools being so positioned as to be on opposite sides of said first and second wall segments, and
- said axial advancing step being operative to collapse said connecting wall and to force a portion of said second pivot region into said recess whereby an arcuate portion of said second wall segment is spaced vertically below said first wall segment and said second pivot region is radially outwardly of said first pivot region.
- 7. A method of forming an end structure for a container wherein an end blank is formed into an end structure which includes means for securing a tab thereto, a scoreline for severance of a central panel from the end wall and protective fold means on said central panel which extends radially outwardly of the scoreline, the improvement which comprises the steps of:
- providing an end blank which includes a wall means for attachment to a container body, said wall means being vertically above and radially outwardly of a radially extending central wall which includes first and second axially spaced radial sections integrally joined by a connecting wall which extends axially between said first and second wall sections;
- the junction of the first wall section and the upper portion of the connecting wall forming a first pivot region and the junction between the second wall section and the lower portion of the connecting wall forming a second pivot region;
- working the end blank between a cooperating die and punch assembly to form a scoreline and to effect movement of at least one of said pivot regions relative to the other whereby said first pivot region is radially inwardly of said second pivot region thereby forming said first wall section and said first pivot region and said connecting wall and said second wall section and said second pivot region into a generally Z-shaped cross-section in which the first and second wall sections form the top and bottom legs of said Z, respectively, and the connecting wall forming the connecting leg thereof; and
- applying an axial compressive force to said first and second wall sections to collapse said connecting wall whereby said first pivot region is radially inwardly of said second pivot region and said scoreline is radially inwardly of said second pivot region.
- 8. A method of forming an end structure for a container wherein an end blank is successively formed into an end structure which includes an integrally formed rivet for securing a tab thereto, a scoreline for severance of a central panel from the end wall and protective fold means which extends radially outwardly of the scoreline, said protective fold including a top layer interconnected to a lower layer by an intermediate layer, said intermediate and lower layer forming the protective fold and said scoreline being in the top layer and radially inwardly of the protective fold, comprising the steps of:
- providing an end blank which includes a curled peripheral wall for attachment to a container body, the curled peripheral wall being vertically above and radially outwardly of a radially extending central wall which includes first and second axially spaced radial sections integrally joined by a connecting wall which extends between said first and second wall sections;
- the junction of the first wall section and the upper portion of the connecting wall forming a first pivot region and the junction between the second wall section and the lower portion of the connecting wall forming a second pivot region;
- working the end blank between a cooperating die and punch assembly to form said scoreline and to effect movement of at least one of said pivot regions relative to the other whereby said first pivot region is radially inwardly of said second pivot region thereby forming said first wall section and said first pivot region and said connecting wall and said second wall section and said second pivot region into a generally Z-shaped cross-section in which the first and second wall sections form the top and bottom legs of said Z, respectively, and the connecting wall forming the connecting leg thereof, the scoreline being in said first wall section and radially outwardly of said second pivot region,
- applying an axial compressive force to said first and second wall sections to collapse said connecting wall whereby said first pivot region is radially inwardly of the second pivot region and said scoreline is radially inwardly of said second pivot region; and
- staking a tab to said central wall.
- 9. A method of forming an end structure for a container wherein an end blank is successively formed through an intermediate stage including a Z-shaped fold which is converted to a generally S-shaped protective fold on an end structure which includes an integrally formed rivet for securing a tab thereto, a scoreline for severance of a central panel from the end wall, the S-shaped protective fold being in the central panel and including a top layer interconnected at one end to a flange and at the other end to a lower layer by an intermediate layer, said scoreline being in the top layer of the protective fold formed by the lower and intermediate layer of said S-shaped fold, comprising the steps of:
- providing an end blank having a curled peripheral wall for attachment to a container body and including a first radial section connected to and adjacent to and vertically below said peripheral wall and a second radial section axially spaced below said first section, said radial sections being interconnected by a connecting wall located between said radial sections;
- the junction of said first radial section and said connecting wall forming a first pivot region and the junction of said second radial section and said connecting wall forming a second pivot region;
- working said end blank to form a scoreline in said first radial section and to effect movement of one of said pivot regions relative to the other thereby forming
- an intermediate stage end blank which includes first and second axially offset radial sections joined by a connecting wall which extends axially, said first and second radial sections and said connecting wall being generally Z-shaped in cross-section with the first and second sections forming the top and bottom legs of said Z, respectively and the connecting wall forming the connecting leg thereof, said intermediate stage end blank including a scoreline in the first wall section, and
- applying an axially compressive force to said first and second wall sections to collapse said connecting wall thereby converting the Z-shaped fold to a generally S-shaped fold including a radially inwardly projecting bend section and a radially outwardly projecting bend section under said inwardly projecting bend section.
CROSS REFERENCE TO RELATED APPLICATION
This is an divisional application of application Ser. No. 336,404, filed on Feb. 28, 1973 for EASY OPENING CONTAINER WALL, now U.S. Pat. No. 3,837,524, and a continuation-in-part of Ser. No. 238,187 filed Mar. 27, 1972, now U.S. Pat. No. 3,765,352.
US Referenced Citations (7)
Divisions (1)
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Number |
Date |
Country |
Parent |
336404 |
Feb 1973 |
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