US3674171A

US3674171A - Fully opening cover of sheet metal for cans

Info

Publication number: US3674171A
Application number: US95551A
Authority: US
Inventors: Hans Joachim Fahlbusch
Original assignee: Schmalback Lubeca AG
Current assignee: Ardagh Metal Beverage Germany GmbH
Priority date: 1969-12-08
Filing date: 1970-12-07
Publication date: 1972-07-04
Anticipated expiration: 1989-07-04
Also published as: DE6947543U; SE360835B; DK133332C; CA936815A; FR2070760B1; DK133332B; FR2070760A1

Abstract

This disclosure relates to a full opening easy opening closure which has an end panel with a graduated spring profile which facilitates expansion and contraction as may occur during the sterilization of a product within a closed container. In order that this spring profile may have no undesirable action which may cause premature opening of the container, the end panel is provided with a shock absorbing bead adjacent the chuck wall and the pull tab is mounted on a platform which extends radially into the spring profile areas, but is not affected thereby.

Description

U United States Patent [151 3,674,171 Fahlbusch July 4, 1972 [54] FULLY OPENING COVER OF SHEET [56] References Cited METAL FOR CANS UNITED STATES PATENTS [72] inventor: Hans Joachim Fahlbusch, Vechelde, Ger- 3,400,853 9/1968 Jacobsen ..220/66 many 3,501,046 3/1970 Jasper et al. ..220/54 [73] Assignee: schmusaltllzag-Lubeca-werke Alrtien- Primary Emminer George "an AttorneyDiller, Brown, Ramik & l-lolt 22 Filed: Dec. 7, 1970 [57] ABSTRACT [21] Appl. No.: 95,551

This disclosure relates to a full opening easy opening closure which has an end panel with a graduated spring profile which Foreign Application Dill I facilitates expansion and contraction as may occur during the 8 1969 Germany G 69 47 543 0 sterilization of a product within a closed container. In order that this spring profile may have no undesirable action which may cause premature opening of the container, the end panel Sil. is provided with a Shock absorbing bead adjacent the chuck [58] Field 0 Search 220/59 48 66 wall and the pull tab is mounted on a platform which extends radially into the spring profile areas, but is not affected thereby.

7 Claims, 3 Drawing Figures PA'TENTEDJIIH m2 3. 674, 17 1 I INVENTDR HANS Joncmm FQHLBUSCH ATTORNEYS FULLY OPENING COVER OF SHEET METAL FOR CANS The invention concerns a fully rip-open cover of sheet metal for cans or similar containers with a score or indented line running near the chuck wall of the cover and concentrically to it, and a pull tab attached by means of a rivet to the cover surface, which lies above a sector of the score line with one break-open edge.

BACKGROUND OF THE INVENTION Full opening covers for cans are known, where a single score line runs close to the chuck wall of the cover and concentrically to it. It has furthermore been known to attach a pull tab to the area which can be torn open in such a way that a rupture initiating edge will lie above the score line, while the tab extends radially to said score line and constitutes a rigid lever which at its free end has a section of a handle.

Furthermore, containers which can be opened easily, have been known, especially for drinks, where a radial tear strip is limited in the cover surface by score lines. There a pull tab has likewise been attached. In order to keep the chuck wall of the cover as free as possible of outside forces, it has been known to provide a concentric dampening or shock absorbing bead projecting to the inside immediately succeeding the chuck wall in the case of these cans, which elastically absorbs the movements of the cover surface under the influence of outside or inside forces.

It has furthermore been known in the case of standard cans for canned goods to provide a graduated profile in the closure, which serves to increase the absorption of volume changes during sterilization by allowing the closure to assume a position arched to the outside.

SUMMARY OF THE INVENTION It is the purpose of the present invention to continue to develop a full opening cover of the type designated in more detail initially in such a manner, that on the one hand the cover will show a good capacity for absorption of volume changes during sterilization, without increasing the danger of a premature ripping open of the cover along the score line, and on the other hand makes possible an attachment of the required tab, without the movements of the cover surface leading to a premature breaking open of the cover along the score line via the pull tab.

According to the invention this problem will be solved through the combination of the following characteristics, namely:

a. that the score line runs closely along the place of transition between a dampening bead limited on the outside by the chuck wall and the cover surface on end panel,

b. the cover surface at a radial distance from the score line has in its cross section a spring profile graduated from the outside to the inside in the manner of terraces defined by several concentric beads or shoulders, and

c. a platform for the attachment of the pull tab which projects from the edge area of the cover surface containing the score line and extending radially inwardly and at the same level as said edge area.

Profiling of the cover surfaces like terraces does not only fulfill the known purpose of absorbing volume, but, in conjunction with the reinforcement of the area receiving the score line by the dampening bead will lead to the surprising consequence that the intended spring movements of the cover surface remain restricted largely to the central area of the cover surface, so that as a result the metal of the cover along the score line is not put under stress. To this must be added that as a result of the dampening bead, the spring movements, insofar as they do continue to the edge area, are absorbed by the dampening bead, without there being any mechanical load on the score line at all.

The reinforcement of the edge area in which the score line is located is increased further by the radially extending platform, which serves for the attachment of the pull tab. This platform pennits a secure and reliable attachment of the tab, and this is accomplished in such a way that it will remain in parallel to the central area of the cover surface, whereby the end of the handle portion of the tab lies at a slight distance above the deepest part of the cover surface, so that the pull tab can easily be grasped. Surprisingly, it turned out that this platform either does not influence the spring movement of the cover or merely changes its shape and position insignificantly in the case of these spring movements of the cover, so that the spring movements of the cover remain without any influence on the pull tab. Therefore, there is no danger for the spring movements of the cover to lead via the pull tab to a premature ripping open of the cover along the score line.

Advantageously the platform at its end pointing toward the center of the closure extends generally conically into the deepest part of the surface cover, so that this portion of the platform represents practically a continuous prolongation of the slanting shoulder lying the farthest inside.

The invention will be explained in more detail subsequently by way of an embodiment and on the basis of a schematic drawing.

FIG. 1 is a top view of a closure according to the invention prior to the attachment of the pull tab.

FIG. 2 is a vertical sectional view through the lid of FIG. 1 on an enlarged scale.

FIG. 3 is an enlarged partial top view of the closure with a pull tab attached.

With reference to the drawing, a container 1 with a closure 2 connected thereto by a double seam 3 is shown in FIGS. 1 and 2. The closure 2 has a chuck wall 4 forming part of the double seam 3, which has immediately adjacent thereto a dampening bead 5 running concentrically over the entire periphery. Immediately adjacent the place of transition between the dampening bead 5 and the closure end surface on end panel there is a score or indented line 6 disposed in concentric relation to the edge. A first concentric shoulder 9 fol-' lowed by two more shoulders 10 and 1 l at spaced intervals lies inside the cover surface at a noticeable distance from the score or weakening line 6, so that the cover surface viewed in cross section has a terrace shaped profile lowered to the inside, as can be seen best from the right half of FIG. 2.

From the edge area, which is confined between the outside shoulder 9 and the dampening bead 5, a radial platform 12 projects radially inwardly. The platfon-n 12 is at the same level as the edge area in which the score line 6 lies. Means for attachment of the pull tab has been provided in the platform and in the case of the example shown is a rivet 7 which is molded out of the metal of the lid.

The platform 12 ends just in front of the central surface part 8 in a front wall 13, that runs approximately conically and which forms a continuous prolongation of the innermost shoulder 11. The latform is bordered furthermore by lateral slanting shoulders 14, which run generally parallel to a radial line and which on the one hand pass over directly into the outward shoulder 9 and on the other hand end in the last platform between the

shoulders

10 and 11 or the inside shoulder 11, respectively.

The terrace-like area constitutes the spring part of the closure, which can arch outwardly, thereby considerably increasing the volume of the container. The platform 12 practically does not participate in this spring movement, and neither does the outside edge area, which lies between the outside shoulder 9 and dampening bead 5 and in which the score line 6 has been provided. This outside edge area does also remain at the same time essentially free of forces which could lead to a premature ripping open of the score line 6. Any possible forces acting on the edge area are largely absorbed by the dampening bead 5, which leads essentially to the reinforcement of the edge area. On the other hand the platform 12 offers a secure place of attachment for the pull tab, which with its hand end projects radially inwardly beyond the platform according to FIG. 3 and which remains above the central part 8 of the closure surface so that the end of the handle of the tab can be grasped easily.

FIG. 3 is a preferred design of the handle flap, attached to the closure according to the invention. The tab has a ring shaped handle element 16, which is formed in one piece and rigidly with the front part ofthe tab via the proper curlings and reinforcements, such as shoulders. At the front end, the pull tab has a force exerting edge 17, which lies immediately above the score line 16. In the front part there is a reces, designated as 18, in which an attaching lobe has been provided by way of a separating line 19, which lobe is firmly connected via a joint with the pull tab, and which at the same time, has a hole which serves for the reception of the attaching rivet. Therivet is shown in FIG. 3 in its beaded position and is therefore designated 20. The pull tab does not come into contact anywhere with the spring part of the closure and does not therefore participate in the movement of that part. Therefore, the opening line can be immediately above the score line 6 without there being any danger that the closure will be ripped open prematurely. The platform 12 also contributes essentially to the reinforcement of the edge area of the lid in which the score line is formed. The spring movements remain restricted to the center part of the closure. The central part 8 of the closure or lid has a considerable distance from the section 16 ofthe handle ofthe tab, so that the latter can be grasped easily.

What is claimed as new:

1. A full opening my opening closure comprising a seam forming portion including a chuck wall, a shock absorbing bead disposed immediately adjacent said chuck wall and surrounding an end panel, a weakening line in said end panel adjacent said shock absorbing bead defining a removable panel portion, said end panel within and spaced from said weakening line having a graduated spring profile defined by a series of concentric axially sloping shoulders, a pull tab secured to said removable panel portion for facilitating the rupture of said end panel along said weakening line and tearing out said removable panel portion, and said end panel including a substantially level platform extending radially inwardly from the area of said shock absorbing bead in underlying relation to said pull tab, said weakening line extending across said platform and said platform interrupting said concentric shoulders, v

andrneamcarriedbysaidplatforrnsecuringsaidpulltabto said removable panel portion with said platform supporting said pull tab independently of flexure of said end panel due to said spring profile.

2. The closure of claim 1 wherein said platform includes a conical radially innermost portion merging into the central part of said end panel.

3. The closure of claim 2 wherein the radially outermost one of said shoulders has a portion thereof at substantially the same level as said platform at the point of attachment of said pull tab.

4. The closure of claim 3 wherein said radially outermost shoulder terminates into inwardly extending shoulders defining the generally radial sides of said platform.

5. The closure of claim 3 wherein said radially outermost shoulder tenninates into inwardly extending shoulders defining the generally radial sides of said platform, and said inwardly extending shoulders terminate into said conical portion.

6. The closure of claim 1 wherein the radially outermost one of said shoulders has a portion thereof at substantially the same level as said platform at the point of attachment of said pull tab.

7. The closure of claim 6 wherein said radially outennost shoulder temrinates into inwardly extending shoulders defining the generally radial sides of said platfonn.

i l 18 l t

Claims

1. A full opening easy opening closure comprising a seam forming portion including a chuck wall, a shock absorbing bead disposed immediately adjacent said chuck wall and surrounding an end panel, a weakening line in said end panel adjacent said shock absorbing bead defining a removable panel portion, said end panel within and spaced from said weakening line having a graduated spring profile defined by a series of concentric axially sloping shoulders, a pull tab secured to said removable panel portion for facilitating the rupture of said end panel along said weakening line and tearing out said removable panel portion, and said end panel including a substantially level platform extending radially inwardly from the area of said shock absorbing bead in underlying relation to said pull tab, said weakening line extending across said platform and said platform interrupting said concentric shoulders, and means carried by said platform securing said pull tab to said removable panel portion with said platform supporting said pull tab independently of flexure of said end panel due to said spring profile.

5. The closure of claim 3 wherein said radially outermost shoulder terminates into inwardly extending shoulders defining the generally radial sides of said platform, and said inwardly extending shoulders terminate into said conical portion.

7. The closure of claim 6 wherein said radially outermost shoulder terminates into inwardly extending shoulders defining the generally radial sides of said platform.