US3404799A

US3404799A - Container

Info

Publication number: US3404799A
Application number: US448596A
Authority: US
Inventors: John J Mcnamara
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1965-04-16
Filing date: 1965-04-16
Publication date: 1968-10-08
Anticipated expiration: 1985-10-08

Description

Oct. 8, 1968 J, MCNAMAR'A 3,404,799

CONTAINER Filed April 16, 1965 JOHN J. McNAMARA ATTORNEYS United States Patent 3,404,799 CONTAINER John J. McNamara, Chicago, Ill., assignor to Continental Can Company, Inc., New York, N.Y., a corporation of New York Filed Apr. 16, 1965, Ser. No. 448,596 8 Claims. (Cl. 220-54) ABSTRACT OF THE DISCLOSURE This disclosure has to do with an easy opening can end wherein the opening of the can is facilitated by shearing the metal of the can entirely through along a starting end portion of a tear strip defined therein primarily by score lines. The sheared through opening in the end is sealed by an extension of a rivet utilized for attaching a pull tab to the tear strip and the pull tab overlies the sheared area to cooperate with the rivet extension.

This invention relates in general to new and useful improvements in containers of the easy opening type, and more particularly relates to a novel container end construction.

This invention particularly relates to easy opening containers of the type wherein a panel of a container is provided with a removable tear strip portion which is torn from the container panel in the opening of the container. Easy opening containers of this general type normally have two major deficiencies. First, inasmuch as rupture of the metal is necessary to eifect the opening of the container, and since very little space is available for the necessary pull tab, it is quite difiicult to open such containers. Secondly, because the pull tabs are normally formed of metal by means of a punching operation, the pull tabs have raw edges on which ones fingers may be readily out should slippage occur during an opening process. This invention proposes to eliminate both of these disadvantages.

In accordance with this invention, it is proposed to form a container panel with a removable tear strip portion by means of a weakening line and a cut line, the cut line defining the starting end of the tear strip. The tear strip is then provided with a pull tab which is capable of sealing the container panel along the cut line and which is preferably formed of a resilient plastic material so as to eliminate the undesired raw edges.

Another object of this invention is to provide a novel easy opening container wherein the pull tab is formed of a resilient plastic material and the problem of sealing the pull tab to the tear strip is eliminated by forming on the inner end of the pull tab a sealing disc which readily seals an aperture in the tear strip through which a portion of the pull tab extends.

A further object of this invention is to provide an easy opening container of the type including a panel in which a tear strip portion is defined by weakening lines, one of the weakening lines being in the form of a cut entirely through the container panel, and a resilient plastic pull tab secured to the tear strip, the pull tab extending through an aperture in the tear strip and having an enlargement on the inner end thereof with the enlargement being of a size to project beyond the tear strip and to seal the out line in the panel, the inner end of the pull tab being of sufficient resiliency so not to unduly resist the tearing out of the tear strip.

With the above and other objects in view that will hereinafter app-ear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

3,404,799 Patented Oct. 8, 1968 In the drawing:

FIGURE 1 is a fragmentary top perspective view of a container formed in accordance with this invention.

FIGURE 2 is an enlarged horizontal sectional view taken along the line 22 of FIGURE 1 and shows more clearly the details of the container end.

FIGURE 3 is an enlarged fragmentary vertical sectional view taken along the line 33 of FIGURE 1 and shows specifically the relationship of the pull tab with respect to the tear strip.

FIGURE 4 is an enlarged fragmentary horizontal sectional view taken along the line 4-4 of FIGURE 3 and shows further the details of the tear strip and the relationship of the pull tab with respect thereto.

FIGURE 5 is a sectional view similar to FIGURE 4 and shows a slightly modified form of the invention.

Referring now to the drawings in detail, it will be seen that there is illustrated a container in the form of a can which is generally referred to by the numeral 10. The can It is formed of a conventional can body 11 which has the bottom end (not shown) closed in a conventional manner. The upper end of the can body 11 is closed by means of a can end, which is formed in accordance with this invention, the can end being generally referred to by the numeral 12. The can end 12 includes a recessed end panel 13 and an outer seam structure which is secured to the can body 11 by means of a conventional double seam 14. The can thus described, is a conventional can.

This invention has to do with the formation of the can 10 so that it may be easily opened. Although reference will be made to an easy opening feature carried by the end panel 13, it is to be understood that the easy opening feature could easily as well be formed in the can body 11 if it is so desired.

The end panel 13 has a first weakening line 15 and a second weakening line 16 formed therein with the weakening line 16 being a continuation of the weakening line 15. The weakening

lines

15 and 16 define a removable tear strip 17. It is pointed out at this time that the illustrated weakening line 15 is in the form of a score line and that the weakening line 16 is in the form of a out line entirely through the end panel 13. v

In order to both seal the end panel 13 along the out line 16 and to facilitate the removal of the tear strip 17, there is provided a pull tab which is generally referred to by the numeral 18. The pull tab 18 includes a generally circular strap portion 19 having a cut out 20 for the reception of ones finger. The pull tab 18 also includes a rivet or plug formation 21 which depends therefrom remote from the cut out 20. When the pull tab 18 is installed with respect to the end panel 13, the rivet portion 21 has a sealing disc 22 at the inner or lower end thereof.

It .is to be noted that the tear strip 17 is provided adjacent the starting end thereof which is defined by the cut line 16 with an aperture 23. The rivet or plug portion 21 passes through and is snugly received within the aperture 23 to effectively seal the same. The sealing disc 22 also aids in the sealing of the aperture 23 in that it is tightly pressed against the underside of the end panel 13 and tightly bears against the underside of the tear strip 17 surrounding the aperture 23.

The sealing disc 22 not only serves to connect the pull tab 18 to the can end panel, but also aids in sealing the aperture 23 and the cut line 16. It will be readily ap parent that since the sealing disc 22 is formed of a resilient material, and is drawn tightly against the underside of the panel 13, it will normally seal the out line 16. However, in order to more positively seal the slit or out line beneath the disc and thereby the end panel 13 a layer of adhesive 24 is placed on the end panel 13 over the area to be covered by the disc 22 before the disc is applied to the end panel. When the disc is formed or 3 placed on the complementary surface of the end panel, the unapertured portion of the strap 19 overlies the cut line 16 and the adhesive 24 is forced into the slit for sealing it. The pressure applied to the disc forces the adhesive 24 through the slit for further bonding the disc to the portion 19 of the tab without bonding the tab to the end panel, thereby providing a unitary sealed structure. Applying the disc to the can end also squeezes the excess adhesive from the space therebetween which provides a supplemental sealing ring of adhesive 25. The strap portion 19 and the sealing disc 22 thereby coperate to reinforce the end panel against accidental rupture thereof at the starting end of the tear strip portion 17.

An alternative procedure that may be preferred eliminates the ring of adhesive 25, as is shown in FIGURE 5. In this embodiment of the invention, the disc 22 may be heat sealed to the surface of the can end. One method of accomplishing this is to form the pull tab from a plastisol, chlorinated polyethylene or other suitable material and cover the surface of the can end with a suitable vinyl coating 26 to which the plastic disc may be bonded by heat.

When it is desired to open the container, it is merely necessary to pass ones finger under the strap portion 19 and to lift the same until ones finger can pass into the cut out 20, An upwardly directed pull may be readily exerted on the pull tab 18 at this time without any danger of ones finger slipping with respect to the pull tab and without any danger of ones finger being cut. When a sufiicient pull is exerted, which pull is less than that which is normally required where rupture of the metal is necessary, that portion of the sealing disc 22 which projects beyond the tear strip 17 and underlies the end panel 13 will deflect sufiiciently to permit the upward movement of the sealing disc 22 together with the starting end portion of the tear strip 17. Once this has been accomplished, the initial seal of the container is broken, and if products are packaged within the container either under pressure or under a vacuum, then venting will take place. A further pull on the pull tab 18 will result in the opening of the container 10 by the removal of the tear strip 17.

At this time it is pointed out that the preferred embodiment of the pull tab is of a one-piece construction with the sealing disc 22 being formed from a part of the rivet or plug portion 21 which projects below the end panel 13 by an application of heat and pressure. However, it is also feasible that the pull tab 18 may be of a two piece construction with either the sealing disc 22 being bonded to the rivet or plug portion 21 or the rivet or plug portion 21 being an integral part of the sealing disc 22 and bonded to the underside of the strap portion 19.

Although only a preferred embodiment of the invention has been specifically illustrated herein, it is to be understood that minor variations may be made in the easy opening container construction without departing from the spirit and scope of the invention, as defined by the appended claims.

I claim:

1. An easy opening container member having a panel, a removable tear strip in said panel, said tear strip being defined in part by a weakening line in said panel and in part by a cut line through said panel, said cut line being a continuation of said weakening line and defining a starting end of said tear strip, a pull tab secured to said tear strip adjacent said starting end and sealing means underlying said cut line and sealed to said panel around said cut line said tear strip being perforated adjacent said starting end and said pull tab having a fastening portion extending through said tear strip and connected to said sealing means with said sealing means aiding in the retention of said pull tab.

2. The container member of claim 1 wherein said sealing means are in the form of a resilient disc and sealing compound between said disc and said panel.

3. The container member of claim 1 wherein said pull tab overlies and protects said tear strip along said cut line.

4. An easy opening container member having a panel, a removable tear strip in said panel, said tear strip being defined in part by a weakening line in said panel and in part by a cut line through said panel, said cut line being a continuation of said weakening line and defining a starting end of said tear strip, an aperture through said tear strip adjacent said starting end, a pull tab secured to said tear strip and having a rivet portion extending through said aperture, and a disc on said rivet portion underlying said out line and sealing said panel.

5. The container member of claim 4 wherein said pull tab is formed of a resilient plastic material.

6. The container of claim 1 wherein said sealing means are in the form of a resilient disc underlying said panel, and means sealing said disc to said panel, said sealing means including adhesive intermediate said disc and said panel.

7. The container of claim 1 wherein said sealing means are in the form of a resilient disc underlying said panel, and means sealing said disc to said panel, said sealing means including a ring of adhesive around said disc.

8. The container of claim 1 wherein said sealing means are in the form of a resilient disc underlying said panel and means sealing .said disc to said panel, said sealing means including a plastic coating on said panel and said disc being formed of a plastic directly bonded to said coating.

References Cited UNITED STATES PATENTS 2,870,935 1/1959 Houghtelling 220--53 3,187,932 6/1965 Cheeley 22054 3,283,945 11/1966 Close 22054 3,151,766 10/1964 Henchert 22054 3,182,852 5/1965 Wilkinson 22054 THERON E. CONDON, Primary Examiner.

G. T. HALL, Assistant Examiner.