US20260176018A1
CAN SHELL, AND ASSOCIATED TOOLING AND METHOD
Publication
Application
Classifications
IPC Classifications
CPC Classifications
Applicants
Stolle Machinery Company, LLC
Inventors
Steven Todd Albright, Dennis Cornelius Stammen, Ian Kenneth Scholey
Abstract
A can shell includes a center panel, an inclined panel wall extending at a downward angle from the center panel, and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall.
Figures
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001]This application claims priority to U.S. Provisional Patent Application Ser. No. 63/736,773, filed Dec. 20, 2024, entitled Can Shell.
FIELD OF THE INVENTION
[0002]The disclosed and claimed concept relates to can shells. The disclosed concept also relates to tooling and associated methods for providing such can shells.
BACKGROUND OF THE INVENTION
[0003]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.
[0004]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.
[0005]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.
[0006]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.
[0007]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.
[0008]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.
[0009]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.
[0010]There is, therefore, a need for improvement in can ends and shells.
SUMMARY OF THE INVENTIONS
[0011]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; and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall.
[0012]In accordance with another aspect of the disclosed concept, a method of forming a can shell comprises: forming a preform shell; and reforming the preform shell into a can shell, wherein the can shell includes a center panel, an inclined panel wall extending at a downward angle from the center panel, and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall.
[0013]In accordance with another aspect of the disclosed concept, tooling for forming a can shell including a center panel, an inclined panel wall extending at a downward angle from the center panel, and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall, the tooling comprises: first tooling structured to reform a preform shell into the can shell, the first tooling including: upper tooling having an upper die center and an upper die ring; and lower tooling having a lower die center and a lower die ring, wherein the upper tooling and the lower tooling are structured to be brought together to reform a preform shell into the can shell, wherein the upper die center includes a central portion corresponding in shape to an upper surface of the center panel and an outer portion corresponding in shape to an upper surface of the inclined panel wall, wherein the lower die center includes an upper surface corresponding in shape to a lower surface of the center panel, and wherein the lower outer die ring includes an inner portion shaped to accommodate the inclined panel wall and the looped countersink.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:
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DETAILED DESCRIPTION OF THE INVENTION
[0038]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.
[0039]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.
[0040]As used herein, the singular form of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
[0041]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].”
[0042]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.
[0043]As used herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).
[0044]
[0045]The can shell 10 includes a center panel 12 and an inclined panel wall 13. The center panel 12 extends radially outward from the center of the can shell 10. The inclined panel wall 13 extends from the outer end of the center panel 12 at a downward angle to an inverted point 19. From the inverted point 19, an inner countersink wall 17 extends downward and inward to an annular countersink 14. The annular countersink 14 loops around to an outer countersink wall 16 which extends upwardly. A chuck wall including a kick portion 20 extends outwardly and upwardly from the outer countersink wall 16. In some example embodiments, the kick portion 20 may have a curved shape. A radiused portion 21 is disposed at the end of the kick portion 20, which turns outwardly to form a flatter shoulder portion 22. A curl 18 is formed at the end of the shoulder portion 22.
[0046]The inclined panel wall 13 inverting at the inverted point 19 into the inner countersink wall 17 provides additional strength and buckle resistance. Further, the annular countersink 14 being formed as a closed loop due to the inverted point 19 being proximate the outer countersink wall 16 also adds strength and buckle resistance. The kick portion 20 additionally provides strength and buckle resistance. Further, the reduced centerline of the annular countersink 14 diameter provides additional strength and buckle resistance.
[0047]
[0048]The preform shell 60 includes a center panel 62 and a curved panel wall 63. The center panel 62 extends radially outward from the center of the preform shell 60. The curved panel wall 63 extends from the outer end of the center panel 62 in a downward curve to an inner countersink wall 64. The inner countersink wall 64 extends substantially straight downward and then curves around to an outer countersink wall 66 which extends substantially straight upward to form an annular countersink 65. A chuck wall including a kick portion 70 extends outwardly and upwardly from the outer countersink wall 66. In some example embodiments, the kick portion 70 may have a curved shape. A radiused portion 71 is disposed at the end of the kick portion 70, which turns outwardly to form a flatter shoulder portion 72. A curl 68 is formed at the end of the shoulder portion 72.
[0049]It will be appreciated that some elements of the preform shell 60 in some example embodiments of the disclosed concept are not subjected to reforming and thus may remain substantially the same as corresponding elements of the can shell 10. For example, the outer countersink wall 16, the kick portion 70, the radiused portion 71, the shoulder portion 72, and the curl 68 of the preform shell 60 may be substantially the same as the outer countersink wall 16, the kick portion 20, the radiused portion 21, the shoulder portion 22, and the curl 18 of the can shell 10 in some example embodiments of the disclosed concept.
[0050]
[0051]The following discussion of dimensions are non-limiting examples. It will be appreciated that dimensions may be varied without departing from the scope of the disclosed concept. Referring to
[0052]A radius R1 of the curl 68 may be about 0.060-0.080 inches, and for example about 0.070 inches. A radius R2 of the shoulder portion 72 may be about 0.010-0.030 inches, and for example about 0.020 inches. A radius R3 of the radiused portion 71 may be about 0.020-0.050 inches, and for example about 0.035 inches. A distance L1 from the top of the curl 68 to the upper surface of the bottom of the annular countersink 65 may be greater than 0.250 inches, or for example about 0.270-0.290 inches, and as a non-limiting example about 0.280 inches. A distance L2 from a bottom surface of the center panel 62 to a bottom surface of the annular countersink 65 may be about 0.120-0.150 inches, and for example about 0.137 inches. A distance L3 from a top to a bottom of the curl 68 may be about 0.060-0.090 inches, and for example about 0.082 inches.
[0053]Referring to
[0054]A distance L4 from a bottom of the annular countersink 65 to the top of the outer countersink wall 66 may be about 0.05-0.06 inches, and for example about 0.055 inches. A distance L6 from a bottom of the annular countersink 65 to the top of the inner countersink wall 64 may be about 0.05-0.06 inches, and for example about 0.057 inches. A distance L5 between the inner countersink wall 64 and the outer countersink wall 66 may be about 0.015-0.050 inches, and for example about 0.019 inches.
[0055]As previously discussed, the dimensions discussed herein are non-limiting examples of dimensions that may be varied without departing from the scope of the disclosed concept.
[0056]
[0057]Referring to
[0058]A radius R9 of the curl 18 may be about 0.060-0.080 inches, and for example about 0.070 inches. A radius R10 of the shoulder portion 22 may be about 0.010-0.030 inches, and for example about 0.020 inches. A radius R11 of the radiused portion 21 may be about 0.020-0.050 inches, and for example about 0.035 inches. A distance L7 from the top of the curl 18 to the upper surface of the bottom of the annular countersink 14 may be greater than 0.250 inches, or for example about 0.270-0.290 inches, and in a non-limiting example about 0.280 inches. A distance L9 from a top to a bottom of the curl 18 may be about 0.060-0.090 inches, and for example about 0.082 inches. In some example embodiments, the radii R9, R10, and R11 and distances L7 and L9 of the can shell 10 may be substantially the same as the corresponding radii R1, R2, and R3 and distances L1 and L3 of the preform shell 60. A distance L8 from a bottom surface of the center panel 62 to a bottom surface of the annular countersink 65 may be about 0.09-0.12 inches, and for example about 0.108 inches.
[0059]Referring to
[0060]A distance L10 from an outer surface of the outer countersink wall 16 to an outer surface of the inverted point 19 may be about 0.010-0.025 inches, and for example about 0.017 inches. A distance L11 from the inverted point 19 to a bottom of the annular countersink 14 may be about 0.030-0.060 inches, and for example about 0.042 inches. A distance L12 from an outer surface of the outer countersink wall 16 to an outer surface of the inner countersink wall 17 may be about 0.025-0.050 inches, and for example about 0.035 inches.
[0061]As previously discussed, the dimensions discussed herein are non-limiting examples of dimensions that may be varied without departing from the scope of the disclosed concept.
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[0063]Both the preform shell 60 and the can shell 10 facilitate easy stacking.
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[0065]In some example embodiments, the can shell 10 is formed from a two-step manufacturing process. In the first step, the preform shell 60 is formed. In the second step, the preform shell 60 is reformed to form the can shell 10. For example, the preform shell 60 is reformed in a conversion press, for example and without limitation, by pressing down on the center panel, causing the inclined panel wall to invert into the inner countersink wall and causing the countersink to become a looped countersink. An example embodiment of tooling to form the preform shell 60 and tooling to reform the preform shell 60 into the can shell 10 will be described with respect to
[0066]
[0067]
[0068]In an example embodiment, the upper die center 212 includes an angled forming surface corresponding in shape to the inclined panel wall 13 of the can shell 10. In an example embodiment the upper outer die ring 214 has a forming surface corresponding to the shape of an upper surface of the can shell 10 from the kick portion 20 to the shoulder portion 22. In some example embodiments, the kick portion 20 to the shoulder portion 22 of the can shell 10 corresponds in shape to the kick portion 70 to the shoulder portion 72 of the preform shell 60 and the upper outer die ring 214 will not reform that area. An upper surface of the lower outer die ring 224 may have an inner portion shaped to accommodate the shape and size of the inclined panel wall 13 and closed loop of the annular countersink 14. That is, an inner portion of the upper surface of the lower outer die ring 224 may accommodate without exerting pressure or forming in this area. The inner portion of the upper surface of the lower outer die ring 224 may include a channel shaped and sized to accommodate the closed loop of the annular countersink 14. The channel serves as a brace for the preform shell 60 while being reformed. An outer portion of the upper surface of the lower outer die ring 224 may include a forming surface with a shape corresponding to a lower surface of the can shell 10 from the kick portion 20 to the shoulder portion 22. In some example embodiments, the kick portion 20 to the shoulder portion 22 of the can shell 10 corresponds in shape to the kick portion 70 to the shoulder portion 72 of the preform shell 60 and the upper pressure pad 214 will have a correspondingly shaped surface and will not reform that area. Accordingly, in some example embodiments, the upper pressure pad 214 and the lower outer die ring 224 may grasp, but not form or reform, the corresponding area of the preform shell 60.
[0069]A lower surface of the upper die center 212 may have a shape corresponding to the can shell 10 from the center of the can shell 10 to an outer edge of the inclined panel wall 13. An upper surface of the lower pressure pad 222 may have a shape and diameter corresponding to the center panel 12 of the can shell 10. When the upper and lower tooling 210,220 are brought together, the upper die center 212 presses the center panel against the lower pressure pad 222. The outer portions of the upper die center 212 corresponding to the shape of the inclined panel wall 13 reforms the curved panel wall 63 of the preform shell 60 into the shape of the inclined panel wall 13 of the can shell 10. The upper die center 212 also presses down on the lower pressure pad 222, causing the spring backing of the lower pressure pad 222 to compress and the lower pressure pad 222 to move downward. This downward movement presses the center panel of the preform shell 60 to move it downward. The reformation causes the inner countersink wall 64 of the preform shell 60 to buckle outward and thus create the inverted point 19 and closed loop annular countersink 14 of the can shell 10. The reforming process also presses the center panel downward thus reducing the distance between the bottom of the center panel and the bottom of the countersink. The upper surface of the lower outer die ring 224 is shaped to accommodate the inclined panel 13 being formed and to allow the inner countersink wall 64 of the preform shell 60 to buckle outward to create the inverted point 19 and closed loop annular countersink 14 of the can shell 10. The spring backing of the upper pressure pad 214 compresses as the upper pressure pad 214 is moved against the lower outer die ring 224 such that as the upper die center 212 continues moving downward, the upper pressure pad 214 remains in place against the lower outer die ring 224 so as not to reform outer areas of the preform shell 60. The use of pressure pads also assists to prevent wrinkling during reformation. Once the tooling 200 has been closed so as to reform the preform shell 60 into the can shell 10, the tooling 200 may be opened and the can shell 10 removed.
[0070]In some example embodiments, a rivet button may be formed in the center of the center panel as part of the process of reforming the preform shell into the can shell 10. For example, the lower pressure pad 222 may include a protruding punch 226 in its center and the upper die center 212 may include a recess 216 in its center. When the tooling 200 is closed, the protruding punch 226 will press a center of the center panel upward into the recess 216 to form a rivet button in the center of the center panel. The rivet button may be used or be further reformed to be used as a rivet to be staked to attach a tab to the can shell 10.
[0071]It will be appreciated that the tooling 100 for forming the preform shell 60 and the tooling 200 for reforming the preform shell 60 into the can shell 10 may be included as part of the same line of machinery. For example, preform shells 60 formed by the tooling 100 may be conveyed to the tooling 200 to be reformed into can shells 10. It will also be appreciated that the tooling 100 and tooling 200 may be independent of each other. For example, preform shells 60 formed by tooling 100 may be packaged or stored and shipped to a different location where they are then reformed into can shells 10 by tooling 200.
[0072]It will be appreciated that can shells as described herein may be subjected to further processing, often referred to as conversion, such as scoring and staking in order to form the can shell into a can end.
[0073]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, an existing can shell (e.g., can shell 50) may be formed of one type of aluminum, but if the existing can shell was formed of a recycled and/or recyclable type of aluminum with less strength or different properties, the existing can shell may 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 shell 10 in 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 shell 10 is 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.
[0074]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.
Claims
What is claimed is:
1. A can shell comprising:
a center panel;
an inclined panel wall extending at a downward angle from the center panel; and
a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall.
2. The can shell of
a chuck wall including a kick portion extending from the outer countersink wall; and
a curl extending radially outwardly from the chuck wall.
3. The can shell of
4. The can shell of
5. The can shell of
6. The can shell of
7. The can shell of
8. The can shell of
9. The can shell of
10. The can shell of
11. The can shell of
12. The can shell of
13. A method of forming a can shell, the method comprising:
forming a preform shell; and
reforming the preform shell into a can shell,
wherein the can shell includes a center panel, an inclined panel wall extending at a downward angle from the center panel, and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall.
14. The method of
15. The method of
16. The method of
17. The method of
18. The method of
19. Tooling for forming a can shell including a center panel, an inclined panel wall extending at a downward angle from the center panel, and a looped countersink formed around the inclined panel wall, the looped countersink starting at an inverted point of the inclined panel wall and looping around to an outer countersink wall, wherein the inverted point is proximate to the outer countersink wall, the tooling comprising:
first tooling structured to reform a preform shell into the can shell, the first tooling including:
upper tooling having an upper die center and an upper pressure pad; and
lower tooling having a lower pressure pad and a lower die ring,
wherein the upper tooling and the lower tooling are structured to be brought together to reform a preform shell into the can shell,
wherein the upper die center includes a central portion corresponding in shape to an upper surface of the center panel and an outer portion corresponding in shape to an upper surface of the inclined panel wall,
wherein the lower pressure pad is spring back and includes an upper surface corresponding in shape to a lower surface of the center panel, and
wherein the lower outer die ring includes an inner portion shaped to accommodate the inclined panel wall and the looped countersink.
20. The tooling of
second tooling structured to form the preform shell, wherein the preform shell includes a center panel, a curved panel wall extending in a downward curve to an inner countersink wall, the inner countersink wall extending substantially straight downward and curving to an outer countersink wall extending substantially straight upward to form an annular countersink, a chuck wall including a kick portion extending from the outer countersink wall, and a curl extending radially outwardly from the chuck wall, the second tooling including:
upper tooling having an upper die center and a number of upper die rings; and
lower tooling having a lower die center and a number of lower die rings,
wherein the upper tooling and the lower tooling are structured to be brought together to form a blank into the preform shell.