Can Shell, and Associated Tooling and Method

This application is non-provisional utility application of and claims priority to U.S. Provisional Patent Application Ser. No. 63/651,063, May 23, 2024, entitled, “Can Shell, And Associated Tooling And Method.”

The disclosed and claimed concept relates to can shells. The disclosed concept also relates to tooling and associated methods for providing such can shells.

Metallic containers (e.g., cans) are structured to hold products such as, but not limited to, food and beverages. Generally, a metallic container includes a can body and a can end. The can body, in an exemplary embodiment, includes a base and a depending sidewall. The can body defines a generally enclosed space that is open at one end. The can body is filled with product and the can end is then coupled to the can body at the open end.

A “can end,” as used herein, is the element coupled to a can body to form a container. The “can end” includes a tab or similar device structured to open the container. As discussed below, “can end” is, typically, formed from a “shell.” That is, a shell is formed from a generally planar blank cut from sheet material. The blank is formed to include an annular countersink, a chuck wall, and other constructs.

A container is exposed to pressures during processing. For example, some food items are cooked and/or sterilized while in the container. Such a container is exposed to both internal pressure, also identified herein as “buckle” or “buckle pressure,” as well as external pressure, also identified herein as “reverse buckle” or “reverse buckle pressure.” A container, that is the can body and the can end, must have the strength to resist deformation due to buckle pressure and/or reverse buckle pressure.

Generally, the strength of the container is related to the thickness of the metal from which the can body and the can end is formed, as well as the shape of these elements. This application primarily addresses the can ends rather than the can bodies. The can ends are either a “sanitary” can end or an “easy open” end. As used herein, a “sanitary” end is a can end that does not have a tab or score profile to open and would have to be opened by use of a can opener or other device. As used herein, an “easy open” can end includes a tear panel and a tab. The tear panel is defined by a score profile, or scoreline, on the exterior surface (identified herein as the “public side”) of the can end. The tab is attached (e.g., without limitation, riveted) adjacent the tear panel. The pull tab is structured to be lifted and/or pulled to sever the scoreline and deflect and/or remove the severable panel, thereby creating an opening for dispensing the contents of the container. The following addresses an “easy open” can end but is also applicable to a “sanitary” can end. That is, a “sanitary” can end is produced in a similar manner, and coupled to a can body in a similar manner. Thus, as used herein, a can end is further defined as including constructs that are used for both “sanitary” can ends and “easy open” ends.

When the can end is made, it originates as a blank, which is cut from a sheet metal product (e.g., without limitation, sheet aluminum; sheet steel). In an exemplary embodiment, the blank is then formed into a “shell” in a shell press. As used herein, a “shell” is a construct that started as a generally planar blank and which has been subjected to forming operations other than rivet forming and tab staking. The shell press includes a number of tool stations where each station performs a forming operation (or which may include a null station that does not perform a forming operation). The blank moves through successive stations and is formed into the “shell.” A shell is, in an exemplary embodiment, a “sanitary” can end that is structured to be coupled to a can body.

For an “easy open” end, a shell is further conveyed to a conversion press, which also has a number of successive tool stations. As the shell advances from one tool station to the next, conversion operations such as, for example and without limitation, rivet forming, paneling, scoring, embossing, and tab staking, are performed until the shell is fully converted into the desired can end and is discharged from the press. Thus, as used herein, a “can end” includes a “shell” as well as a construct including a tab and a score line.

In the can making industry, large volumes of metal are required in order to manufacture a considerable number of cans. An ongoing objective in the industry is to reduce the amount of metal that is consumed. Efforts are constantly being made, therefore, to reduce the thickness or gauge (sometimes referred to as “down-gauging”) of the stock material from which can ends, tabs, and can bodies are made. However, as less material (e.g., thinner gauge) is used, problems arise that require the development of unique solutions. When the base gauge of the metal is too thin, the can end can have insufficient buckle resistance and can deform.

There is, therefore, a need for improvement in can ends and shells.

In accordance with an aspect of the disclosed concept, a can shell comprises: a center panel; an inclined panel wall extending at a downward angle from the center panel; an annular countersink formed around the inclined panel wall, the annular countersink including an inner countersink wall and an outer countersink wall; a chuck wall extending from the outer countersink wall, the chuck wall including a kick portion having a curved shape beginning at a point lower than a lowest point of the inclined panel wall; and a curl extending radially outwardly from the chuck wall.

In accordance with another aspect of the disclosed concept, tooling for forming a can shell comprises: an upper tool assembly; and a lower tool assembly, said upper tool assembly and said lower tool assembly are structured to cooperate and to form a can shell, said can shell including a center panel, an inclined panel wall extending at a downward angle from the center panel, an annular countersink formed around the inclined panel wall, the annular countersink including an inner countersink wall and an outer countersink wall, a chuck wall extending from the outer countersink wall, the chuck wall including a kick portion having a curved shape beginning at a point lower than a lowest point of the inclined panel wall, and a curl extending radially outwardly from the chuck wall.

In accordance with another aspect of the disclosed concept, a method of forming a can shell comprises: providing a blank; providing a tooling with an upper tool assembly and a lower tool assembly; introducing the blank between the upper tool assembly and the lower tool assembly; forming the blank to include a center panel, an inclined panel wall extending at a downward angle from the center panel, an annular countersink formed around the inclined panel wall, the annular countersink including an inner countersink wall and an outer countersink wall, a chuck wall extending from the outer countersink wall, the chuck wall including a kick portion having a curved shape beginning at a point lower than a lowest point of the inclined panel wall, and a curl extending radially outwardly from the chuck wall.

It will be appreciated that the specific elements illustrated in the figures herein and described in the following specification are simply exemplary embodiments of the disclosed concept, which are provided as non-limiting examples solely for the purpose of illustration. Therefore, specific dimensions, orientations, assembly, number of components used, embodiment configurations and other physical characteristics related to the embodiments disclosed herein are not to be considered limiting on the scope of the disclosed concept.

Directional phrases used herein, such as, for example, clockwise, counterclockwise, left, right, top, bottom, upwards, downwards and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein.

As used herein, the singular form of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.

As used herein, “structured to [verb]” means that the identified element or assembly has a structure that is shaped, sized, disposed, coupled and/or configured to perform the identified verb. For example, a member that is “structured to move” is movably coupled to another element and includes elements that cause the member to move or the member is otherwise configured to move in response to other elements or assemblies. As such, as used herein, “structured to [verb]” recites structure and not function. Further, as used herein, “structured to [verb]” means that the identified element or assembly is intended to, and is designed to, perform the identified verb. Thus, an element that is merely capable of performing the identified verb but which is not intended to, and is not designed to, perform the identified verb is not “structured to [verb].”

As used herein, “associated” means that the elements are part of the same assembly and/or operate together, or, act upon/with each other in some manner. For example, an automobile has four tires and four hub caps. While all the elements are coupled as part of the automobile, it is understood that each hubcap is “associated” with a specific tire.

As used herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).

are various views of a can shellin accordance with an example embodiment of the disclosed concept.is a top isometric view of the can shellin accordance with an example embodiment of the disclosed concept.is a bottom isometric view of the can shell.is a side view of the can shell.is a cross-sectional side view of the can shell.is an enlarged detail view of the can shelltaken from calloutinand linein.is a top plan view of the can shell.is a bottom plan view of the can shell.

are various comparison views of the can shellin accordance with an example embodiment of the disclosed concept with respect to an existing can shell.is a cross-sectional comparison of the can shellwith the existing can shell.is a cross-sectional comparison of the can shellattached to a can body with the existing can shell.is an overlay comparison of the can shellwith the existing can shell.

The can shellincludes a center panel, an inclined panel wall, an annular countersink, a chuck wall, and a curl. The center panelextends radially outward from the center of the can shell. The inclined panel wallextends from the outer end of the center panelat a downward angle to the annular countersink. The annular countersinkincludes an inner countersink walland an outer countersink wall. The chuck wallextends upward from the outer countersink wallto the curl. The can shellmay be formed from a substantially planar blank. The can shellmay be converted into a can end in a subsequent conversion process, which may include forming a rivet in the can shell, scoring a tab opening in the can shell, and staking a tab to the can shell.

The can shellin accordance with an example embodiment of the disclosed concept includes a kick portionin the chuck wall. The kick portionhas a curved shape which has a radius Rwith respect to a point on an exterior of the can shell. That is, the kick portionhas a concave shape with respect to an exterior of the can shell. In some example embodiments, the kick portionmay extend from the outer countersink wallto an inner wallof the curl. In some example embodiments, the kick portionmay comprise the entire chuck wall. In some example embodiments, the kick portionmay comprise a portion of the chuck wall. For example, the kick portionmay extend from the outer countersink wallto an upper chuck wall portion. The upper chuck wall portionmay extend from the kick portionto the inner wallof the curl. Similarly, in some example embodiments, a lower chuck wall portion may be disposed between the outer countersink walland the kick portion. In some example embodiments, the kick portionbegins in a plane below the lowest point of the inclined panel wall. That is, the curved shape of the kick portionof the chuck wallbegins at a lower point of the chuck wallbelow the lowest point of the inclined panel wall.

The can shellin accordance with example embodiments of the disclosed concept provides increased resistance to buckle pressure than the existing can shell. Further, the can shellis interchangeable with the existing can shell. That is, the can shellmay be converted into a can end and attached to the same can bodies as the existing can shell. Further, the can shellcan utilize the same size blank and same amount of metal as the existing can shell. In some example embodiments, as the can shellprovides increased resistance to buckle pressure with respect to the existing can shell, the can shellmay use a lower gauge of metal, and thus reduce metal usage while still providing adequate resistance to buckle pressure.

As shown in, the existing can shellincludes a center panel, an inclined panel wall, an annular countersink, and a curlsimilar to the can shellin accordance with an example embodiment of the disclosed concept. However, the chuck wallin the existing can shelldoes not include the kick portionof the can shell. Rather, the chuck wallextends linearly from an outer countersink wallto an upper chuck wall portion. That is, the chuck wallof the existing can shellhas a linear shape that extends directly in a linear path from the outer countersink wallto a point above the lowest point of the inclined panel wall.

As noted above, the can shellin accordance with example embodiments of the disclosed concept provides increased resistance to buckle pressure over the existing can shellby providing the kick portionin the chuck wall. It will be appreciated that in some example embodiments of the disclosed concept, the kick portionbegins at a point lower than the lowest point of the inclined panel wall. In addition to increased resistance to buckle pressure, the can shellis interchangeable with the existing can shell, thus allowing the can shellto be used with existing tooling for converting can shells into can ends as well as with existing tooling for attaching can ends to can bodies. Further, the can shellcan use the same size blanks and amount of metal used to form the existing can shell, thus allowing a current supply of blanks to form the can shellin accordance with an example embodiment of the disclosed concept. Additionally, the can shellcan use a lower gauge blank than the existing can shell, thus reducing metal usage.

is an overlay comparison of the can shelland the existing can shell. It will be appreciated that in some example embodiments, the existing can shellcan be converted into the can shellin accordance with an example embodiment of the disclosed concept. That is, the kick portioncan be formed in the chuck wallof the existing can shellin order to form the can shellin accordance with an example embodiment of the disclosed concept. It will be appreciated that the conversion may be performed as an addition to the shell forming process or as part of the process of converting the can shell to a can end.

Whileis described in reference to converting the existing can shellto the can shellin accordance with an example embodiment of the disclosed concept, it will also be appreciated that the can shellmay be formed from a blank where the kick portionis formed directly rather than forming a linear chuck wall first and them forming the kick portionin the linear chuck wall.

is a cross-sectional view of tooling for forming the can shellandare cross-sectional views of tooling for forming the existing can shell. The tooling for forming the can shellincludes upper tooling and lower tooling. The upper tooling includes an inner pressure sleeveand die center, and the lower tooling includes a die core ring. A blank is disposed between the upper tooling and the lower tooling, and the upper tooling is pressed onto the lower tooling to form the can shell. In the process of pressing the upper tooling onto the lower tooling, the inner pressure sleeveis pressed onto the die core ringto form the chuck wallincluding the kick portionof the can shell. The shape of the inner pressure sleeveand die core ringcorresponds to the shape of the chuck wallincluding the kick portionso as to form the chuck wallincluding the kick portion.

show the tooling to form the existing can shell. The tooling included upper tooling and lower tooling. However, the tooling inincludes an inner pressure sleeve, die core ring, and die centerhaving a different shape than the inner pressure sleeve, die core ring, and die centerfor forming the can shellin accordance with example embodiments of the disclosed concept. For example, the inner pressure sleeveincludes a deeper countersink forming portion and the die core ringhas a corresponding shape. Additionally, the die centerdoes not include a notched edge. In some example embodiments, the tooling for forming the existing can shellcan be retrofitted to form the can shellby replacing the inner pressure sleeve, die core ring, and die centerwith the inner pressure sleeve, die core ring, and die centerof.

It will be appreciated that the disclosed concept also covers methods of forming the can shell. The disclosed concept covers methods of forming the can shellfrom a blank as well as methods of forming the can shellfrom the existing can shell. It will also be appreciated that the disclosed concept also covers forming the can shellin the shell forming process, as well as forming the can shellin the conversion process, such as in a conversion press.

Market demands have increased the desire of can manufacturers to use recycled and/or recyclable materials for multiple reasons, including considerations of both cost and environmental impacts. In addition, the inclusion of recycled and/or recyclable materials is a desirable marketing concept that is attractive to both product vendors and end consumers. However, some recycled and/or recyclable materials may have less strength than common materials used in existing can shells. For example, the existing can shellmay be formed of one type of aluminum, but if the existing can shellwas formed of a recycled and/or recyclable type of aluminum with less strength or different properties, the existing can shellmay not be able to provide sufficient resistance to buckle pressure and may have to result to using a thicker gauge, and thus more material, to compensate. The can shellin accordance with example embodiments of the disclosed concept provides an increased resistance to buckle pressure, and thus may be formed of materials having less strength, such as for example and without limitation, recycled and/or recyclable materials having less strength than standard materials, and still provide sufficient resistance to buckle pressure without using an increased gauge or more material. It will be appreciated that in some embodiments, the can shellis composed of aluminum and in some embodiments the can shell is composed of a recycled and/or recyclable type of aluminum that has less strength than type of aluminum commonly used for existing can shells.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of disclosed concept which is to be given the full breadth of the claims appended and any and all equivalents thereof.