Can End With Removable Tab Closure

Abstract

A can end has a pouring aperture and a smaller venting aperture both of which are covered and sealed by an elongated removable tab having integral rivet portions corresponding to the size and configuration of the apertures in the can and positioned within the apertures. The integral rivet portions are riveted to compress a gasket between the tab and the top of the can but the formation of the rivet is incomplete so that the tab may be manually removed from the can end by pulling the rivet portions of the tab out of engagement with the apertures in the can end. A finger grip is provided on the tab remote from the pouring aperture, and the tab is constructed to bend along a line transverse to and between the rivet portions so that the rivet engaged within the vent aperture is withdrawn from the vent aperture before the other rivet portion is withdrawn from the pouring aperture. A portion of the can end at the side of each aperture closest to the finger grip is weakened by the score lines permitting the can to distend upon upward displacement of the finger grip to reduce the pulling force required to remove the integral rivets from the apertures.

Description

The present invention relates to can ends of the type having removable tab openers.

At present there are available can ends having integral tear strips for permitting a large opening to be made in the can end without the necessity of employing conventional can opening means. Containers having the aforementioned type of can ends have found wide acceptance. However, it is known that the depth of the score lines along the tear strip must be controlled accurately in the manufacturing process in order to ensure removal of the strip with a minimum of effort. Because of the lower strength of aluminum, the depth of the score lines is not as critical in aluminum as in steel and aluminum has been the choice of container manufacturers for tear strip closures. However, aluminum can ends when used on cans fabricated of other metals such as steel create other problems which make them less desirable than steel can ends. In addition, aluminum is more costly than steel. Thus, can ends which are fabricated of steel are desirable.

With the foregoing in mind, it is a primary object of the present invention to provide a novel container closure having a removable tab opener.

It is another object of the present invention to provide an improved steel can end which may be mated with a container of like material and which may be easily opened to permit access to the product within the container.

As a further object, the present invention provides a new can end having a removable tab opener which is capable of being removed with a minimum of effort and which is economical to fabricate.

It is a still further object of the present invention to provide an improved can end having a relatively large pouring aperture and a smaller venting aperture and having a removable tab which is constructed to uncover the venting aperture prior to uncovering the pouring aperture.

More specifically, the present invention provides a can end shaped to mount on the open end of a container and having an elongated, removable tab means with one partial rivet snugly engaged in a pouring aperture and another partial rivet snugly engaged in a smaller venting aperture in the can end. Gasket means is provided between the underside of the tab means and the top of the can end around each aperture, and each partial rivet has a rim engaging the underside of the member to compress the gasket and effect an air and fluid tight seal. Grip means is provided on the tab means at a location remote from the pouring aperture and to one side of the venting aperture, and the tab means has a transverse zone which is weak in bending between its rivet portions so that the grip may be pivoted to cause uncovering of the venting aperture prior to the pouring aperture for equalizing the pressure inside the container. It addition, means is provided to weaken the portion of each aperture which is closest to the grip means to enable the can end to distend along a portion of each aperture for reducing the force required to effect disengagement of the tab from the can end.

These and other objects, features and advantages of the present invention should become apparent from the following description when taken in conjunction with the accompanying drawing in which:

FIG. 1 is a plan view of a can end embodying the present invention;

FIG. 1a is an exploded perspective view showing the can end of the present invention with its tab means separated from the can end;

FIG. 2 is an enlarged fragmentary view of the can end of FIG. 1;

FIG. 3 is an enlarged sectional view taken along line 3--3, FIG. 2, and illustrating the downwardly concave configuration of the depressed portions of the tab means before they are partially riveted to secure the tab to the can end;

FIG. 4 is an enlarged fragmentary longitudinal sectional view of the partially riveted portions of the tab means, the view illustrating a rim formed around each riveted portion upon compression between die members;

FIG. 5 is an enlarged fragmentary sectional view illustrating compressed gasket means located between the tab means and the can end, the compression resulting from the formation of the rims around the partially riveted portions; and

FIG. 6 is a perspective view of a form of gasket employed in the present invention.

Referring now to the drawing, there is illustrated in FIG. 1 a can end 10 embodying the present invention. As illustrated therein, the can end is shaped to engage the open end of a cylindrical container body 12 and includes a circular pouring aperture 13 located adjacent its periphery and a smaller circular venting aperture 14 located centrally of the can end. The apertures 13 and 14 are covered and sealed by a tab 15 positioned on the top of the can end and which is removable to uncover the apertures preparatory to the pouring of contents from the container 12. In the present instance, both the can end 10 and tab 15 are fabricated from steel.

As noted heretofore, aluminum has been the choice of container manufacturers for tab-type can ends because its relatively low strength permits fabrication of can ends having removable tabs which are capable of being opened with a minimum of effort. Although steel is economically more desirable for can ends than aluminum its strength has presented a drawback to the production of can ends which are capable of being opened with substantially the same effort as required for aluminum closures. Accordingly, a can end which is relatively easy to open and which is economical to produce is highly desirable.

The present invention provides a can end which eliminates the aforementioned limitations of prior art by being economical to manufacture and capable of being opened with a minimum of effort. To this end, the tab 15 has a rivet-like portion 16 matingly engaged in the pouring aperture 13 and another rivet-like portion 17 matingly engaged in the venting aperture 14 (see FIG. 3). The tab 15 has a flat surface 15a confronting the top of the can end 10 and surrounding the rivets 16 and 17; and gasket means, in the present instance a flat, oval, resilient element 20 (FIG. 6) having apertures 21 and 22 for receiving the rivets 16 and 17, respectively, is disposed between the surface 15a and the top of the can end 10 to provide an air and fluid-tight seal therebetween. As may be seen in FIGS. 4 and 5, the tab 15 is removably secured to the can end 10 by means of rims 16a and 17a which engage the underside of the can end around the apertures 13 and 14 and which are formed by partially deforming the rivets 16 and 17, respectively, between dies which engage opposite sides of the rivets 16 and 17 as illustrated in broken lines in FIG. 4. During the riveting operation, as may be seen in FIG. 5, the gasket 20 is compressed slightly around the edges of the apertures 13 and 14 and between the tab 15 and can end 10 to form a fluid and air tight seal at the apertures. As an alternative to having a separate gasket 20, the gasket may be molded directly on the underside of the tab around the rivet portions 16 and 17.

The tab 15 is readily removable from the can end 10. To this end, grip means, in the present instance an elongated opening 25, is provided in the tab 15 at the end of the tab remote from the pouring aperture 13. The opening 25 extends transversely to the longitudinal dimension of the tab 15, and the opening 25 is sized to receive a person's index finger. As may be seen in FIGS. 2 and 3, a flange 26 projects upwardly from the tab 15 around its periphery and surrounds the opening 25, and a slight gap 27 is provided between the top of the can end 10 and the underside of the grip to enable a person to obtain a firm hold on the tab 15 preparatory to its being disengaged from the can end 10.

The tab 15 is disengaged from the can end 10 when the grip 25 is displaced upwardly (see FIG. 1a). It is to be noted, however, that some with certain products, and particularly those which are packaged hot and then cooled, a vacuum may be created in the container. As a result, the pressure differential on opposite sides of the rivets 16 and 17 would normally tend to increase the effort required to disengage the tab 15.

In accordance with the present invention, the tab 15 is constructed in such a manner as to first uncover the venting aperture 17 before disengagement of the tab from the pouring aperture is initiated. For this purpose, means is provided to weaken the tab 15 in a transverse zone between the rivets 16 and 17. In the present instance, the weakened zone is provided by terminating the flange end at abrupt shoulders 30, 30 adjacent opposite sides of the rivet 16. Thus, when the grip 25 is displaced upwardly, the tab 15 bends to enable the grip 25 to be pivoted upwardly to first withdraw the rivet 17 from the venting aperture 14. Further upward movement of the grip 25 permits the rivet 16 to be withdrawn from the pouring aperture 13 with a minimum of effort.

In order further to reduce the effort required to remove the tab 15, means is provided along the portions of the apertures 13 and 14 closest to the grip 25 to enable the can end to distend adjacent the apertures upon withdrawal of the rivet rims 16a and 17a from the apertures 13 and 14, respectively. In the present instance, the distension-providing means includes a series of radially extending score marks 32 and 33 in the top of the can end 10 adjacent the apertures 13 and 14, respectively. Thus, the strength of the can end 10 is reduced in these two zones to enable the tab 15 to be removed with a minimum of effort.

In view of the foregoing, it should be apparent that an improved can end which is economical to manufacture and which may be opened with a minimum of effort has been provided.

While a preferred embodiment of the present invention has been described in detail, various modifications, alterations and changes may be made without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

I claim:

1. In a can end for a container, said can end having means defining a first aperture to permit pouring of contents from the container and a second aperture to permit venting of the container during pouring, a removable elongated tab disposed on one side of said can end, said tab having first and second rivet portions engaging in respective ones of said apertures, each rivet portion having a rim engaging the other side of said can end around its associated aperture to removably secure said tab to said can end, grip means located on said tab a greater spaced distance from said first rivet portion than from said second rivet portion, and means providing at least one weakened zone transversely of said tab to permit bending of said tab between said rivets upon displacement of said grip means away from said can end, so that displacement of the grip means causes the second aperture to be uncovered before the first.

2. Apparatus according to claim 1 wherein said tab has a surface surrounding said rivets and confronting said one side of the can end around said apertures, and including gasket means disposed between said tab surface and said one side of the can end.

3. Apparatus according to claim 1 wherein said apertures are circular with said first aperture having a diameter larger than the diameter of said second aperture and said rivet portions engage snugly in their respective apertures.

4. Apparatus according to claim 1 including means providing distensible zones in said can end adjacent a portion of each aperture located closest to said grip means.

5. Apparatus according to claim 4 wherein said distensible zone-producing means includes a series of score lines in said can end extending outwardly away from each aperture in said one side of said can end.

6. Apparatus according to claim 1 wherein said closure means and said tab are each of steel construction.

7. Apparatus according to claim 1 wherein said tab has a peripheral flange projecting away from said can end and said means providing said weakened zone include abrupt shoulder portions formed on said flange.