Method and apparatus for can expansion
11253904 · 2022-02-22
Assignee
Inventors
Cpc classification
International classification
Abstract
An expansion tool for expanding an article. The expansion tool includes a lead-in portion extending outwardly from a first end of the expansion tool and a first pilot portion extending from the lead-in portion. The first pilot portion has a first diameter. The expansion tool further includes a second pilot portion being generally parallel with the first pilot portion. The second pilot portion has a second diameter larger than the first diameter. The expansion tool further includes a forming portion bridging the first pilot portion and the second pilot portion. The forming portion is generally sloped. The expansion tool further includes an expansion portion extending from the second pilot portion toward a second end of the expansion tool. The expansion portion has a third diameter larger than the second diameter.
Claims
1. An expansion tool for expanding an article, the expansion tool comprising: a lead-in portion extending outwardly from a first extreme end of the expansion tool; a first pilot portion extending from the lead-in portion, the first pilot portion having a first diameter; a second pilot portion being generally parallel with the first pilot portion, the second pilot portion having a second diameter larger than the first diameter; a forming portion bridging the first pilot portion and the second pilot portion, the forming portion being generally sloped; a first expansion portion extending from the second pilot portion toward a second extreme end of the expansion tool, the first expansion portion having a third diameter larger than the second diameter, the second extreme end being generally opposite the first extreme end; a second expansion portion having a fourth diameter larger than the third diameter; a sloped relief portion extending from the first expansion portion, the relief portion having a fifth diameter smaller than the third diameter; a generally inclined land bridging the relief portion and the second expansion portion; and a second sloped relief portion extending from the second expansion portion, the second relief portion having a sixth diameter smaller than the fourth diameter.
2. The expansion tool of claim 1, wherein the expansion tool is for expanding an article to form a contoured outer surface.
3. The expansion tool of claim 1, wherein the lead-in portion is generally sloped.
4. The expansion tool of claim 1, wherein the second relief portion is positioned at the second extreme end of the expansion tool.
5. An expansion mechanism for expanding an article, the expansion mechanism comprising: a first expansion tool including a first lead-in portion extending outwardly from a first end of the first expansion tool, a first pilot portion extending from the first lead-in portion, the first pilot portion having a first diameter, a first expansion portion, the first expansion portion having a second diameter, the second diameter being larger than the first diameter, and a first land bridging the first pilot portion and the first expansion portion and configured to form a deformity in a sidewall of the article; and a second expansion tool configured to be used subsequent to the first expansion tool, the second expansion tool including a second lead-in portion extending outwardly from a first end of the second expansion tool, a second pilot portion extending from the second lead-in portion, the second pilot portion having a third diameter, the third diameter being generally equal to the first diameter, a third pilot portion being generally parallel to the second pilot portion, the third pilot portion having a fourth diameter, the fourth diameter being generally equal to the second diameter, a forming portion bridging the second pilot portion and the third pilot portion, a second expansion portion having a fifth diameter, the fifth diameter being larger than the third diameter, and a second land bridging the third pilot portion and the second expansion portion, wherein the axial distance from the first end of the first expansion tool to the first land is generally the same as the axial distance from the first end of the second expansion tool to the forming portion such that the forming portion is configured to contact and smoothen the deformity formed by the first land of the first expansion tool.
6. The expansion mechanism of claim 5, wherein the first diameter is generally equal to an initial diameter of the article.
7. The expansion mechanism of claim 5, wherein the first and second lead-in portions are generally sloped.
8. The expansion mechanism of claim 5, wherein the forming portion is generally sloped.
9. A method of expanding an article, the method comprising: inserting a first end of a first expansion tool into an open end of the article, the first expansion tool having a first pilot portion followed by a first expansion portion, the first pilot portion having a first diameter generally equal to an initial diameter of the article, the first expansion portion having a second diameter, the second diameter being greater than the first diameter, the first expansion portion forming a partially expanded article having an expanded portion, the first expansion portion forming at least one deformity in the expanded portion of the article; and inserting a first end of a second expansion tool into the open end of the partially expanded article, the second expansion tool including a second pilot portion having a third diameter, a third pilot portion having a fourth diameter, the fourth diameter being generally equal to the second diameter and greater than the third diameter, a first forming portion bridging the second and third pilot portions, the first forming portion being generally sloped, and a second expansion portion extending from the third pilot portion, the second expansion portion having a fifth diameter, the fifth diameter being greater than the second diameter, the first forming portion smoothing the at least one deformity formed in the expanded portion of the article.
10. The method of claim 9, wherein the first expansion tool includes a land bridging the first pilot portion and the first expansion portion, the at least one deformity having generally the same shape as the land.
11. The method of claim 10, wherein the first expansion tool and the second expansion tool are inserted generally the same distance into the article.
12. The method of claim 11, wherein the distance from the first end of the first expansion tool to the land is generally the same as the distance from the first end of the second expansion tool to the first forming portion.
13. The method of claim 9, wherein the second expansion portion forms a second at least one deformity in the expanded portion of the article, the method further comprising, after inserting the second expansion tool, inserting a first end of a third expansion tool into the open end of the article, the third expansion tool including a fourth pilot portion having a sixth diameter, a fifth pilot portion having a seventh diameter, the seventh diameter being generally equal to the fifth diameter and greater than the sixth diameter, a second forming portion bridging the fourth and fifth pilot portion, the second forming portion being generally sloped, and a third expansion portion extending from the fifth pilot portion, the third expansion portion having an eighth diameter greater than the seventh diameter, the second forming portion smoothing the second at least one deformity.
14. The method of claim 13, wherein the second expansion tool includes a second land bridging the third pilot portion and the second expansion portion, the second at least one deformity having generally the same shape as the second land.
15. The method of claim 14, wherein the second expansion tool and the third expansion tool are inserted generally the same distance into the article.
16. The method of claim 15, wherein the distance between the first end of the second expansion tool and the second land is generally the same as the distance between the first end of the third expansion tool and the second forming portion.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Exemplary embodiments are illustrated in referenced figures. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.
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(13) While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DESCRIPTION OF ILLUSTRATED EMBODIMENTS
(14) Existing expansion processes and apparatus suffer from a number of significant limitations. In particular, for example, expansion tools used in conventional expansion processes often have limited piloting. Lack of sufficient piloting often provides inadequate guiding of an article or container during expansion operations, thereby causing the container to be off-center relative to the expansion tool, which may lead to uneven forming, undesirable thinning or even splitting of a portion of the container material, or the like.
(15) According to aspects of the present disclosure, apparatus and methods are described for improving article (e.g., container) expansion processes. Articles formed using the embodiments described herein may have an expanded portion formed by an expanded portion of an expansion tool. The expanded portion may have a greater diameter than, e.g, the unexpanded portion of the article.
(16) The articles described herein may be a can, any suitable food or beverage container, jar, bottle or any other suitable article. The article has an open end opposite a closed end and a sidewall extending from the closed end. Alternatively, the article may be open at both ends. A top, lid, or other closure can be added to the article after the expansion process.
(17) For exemplary purposes only, the below description will describe the expansion apparatus and methods for use on a container. It will be recognized that the methods and apparatus described herein may be used with any suitable article.
(18) According to the embodiments described herein, an expansion mechanism includes two or more expansion tools in which there is constant piloting, or guiding, during each expansion such that the expansion tool remains generally centralized within the container. As such, uneven expansion/forming, undesirable/uneven thinning, splitting, bulges, and the like may be minimized.
(19) According to one embodiment, an expansion tool for expanding an article includes a lead-in portion extending outwardly from a first end of the expansion tool and a first pilot portion extending from the lead-in portion. The first pilot portion has a first diameter. The expansion tool further includes a second pilot portion being generally parallel with the first pilot portion. The second pilot portion has a second diameter larger than the first diameter. The expansion tool further includes a forming portion bridging the first pilot portion and the second pilot portion. The forming portion is generally sloped. The expansion tool further includes an expansion portion extending from the second pilot portion toward a second end of the expansion tool. The expansion portion has a third diameter larger than the second diameter.
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(21) The expansion process shown in
(22) When the first expansion tool 12 is inserted a predetermined distance into the interior of the container in the direction of Arrow A, the expansion portion 22 contacts and expands the interior sidewall of container. The expansion diameter 28 of the expansion portion 22 is greater than the initial diameter 26 of the container 18, thereby dictating and forming the first expanded diameter (diameter 40 of
(23) As shown in
(24) Following the first expansion process of
(25) The second pilot diameter 40 is generally equal to the diameter 26 of the expanded portion 30 of the container 18b. As such, the second pilot portion 38 fits generally snugly therein, thereby axially guiding the container 18b and maintaining it in a generally central position with respect to the second expansion tool 38. Once the second expansion tool 14 has been inserted a predetermined distance into the container 18b at the end of an expansion stroke, the first pilot portion 34 contacts the downstream, generally unexpanded portion 31 of the container 18b. During this axial movement, the forming portion 42 contacts the deformity 33 formed during the first expansion (see
(26) In one embodiment, the second expansion tool 14 may be inserted generally the same predetermined distance relative to the distal end 50 of the container 18c (see
(27) It is contemplated that the second expansion tool 14 may be inserted a greater or a smaller distance relative to the distal end 50 of the container 18c than the first expansion tool 12. In such embodiments, the axial distance from the first end 32 of the second expansion tool 14 to the forming portion 42 should be such that the forming portion 42 may contact and smoothen the deformity 38 formed by the first expansion tool 12 in the previous expansion process. For example, if the second expansion tool 14 is to be inserted a smaller distance into the container 18c (farther from the distal end 50 of the container), the forming portion 42 should be positioned a shorter distance from the first end 32 of the second expansion tool 14.
(28) As described above, a subsequent expansion operation utilizes an expansion tool that includes a secondary pilot portion (e.g., second pilot portion 38 of
(29) During the expansion operation, the container is located by the second pilot portion and expanded by the geometry of the expansion portion located behind the second pilot portion. As the expansion tool nears the end of the expansion stroke, the bump or deformity created during the prior expansion operation is smoothened by the forming portion. Thus, the expansion operations and tools of the embodiments described herein perform two operations at once—smoothening and further expanding.
(30) This may be repeated throughout the remaining expansion process until the desired container shape is achieved. As such, the next expansion operation may repeat the process of blending/smoothing and expanding.
(31) It is contemplated that any number of expansion operations utilizing a respective number of expansion tools may be used to form a desired shape of a final container. Optionally, at the end of an expansion operation, a final expander (see final expander 102 of
(32) The ratio of expanding and blending operations may be varied based on the desired shape of the finished container. For example, the container may be subjected to multiple expansion operations (thereby creating multiple deformities or bumps) before being subjected to smoothening (or multiple smoothening processes).
(33) According to one embodiment, an expansion mechanism for expanding an article includes a first expansion tool and a second expansion tool. The first expansion tool includes a first lead-in portion extending outwardly from a first end of the first expansion tool and a first pilot portion extending from the first lead-in portion. The first pilot portion has a first diameter. The first expansion tool further includes a first expansion portion having a second diameter that is larger than the first diameter. The first expansion tool further includes a first land bridging the first pilot portion and the first expansion portion. The second expansion tool includes a second lead-in portion extending outwardly from a first end of the second expansion tool and a second pilot portion extending from the second lead-in portion. The second pilot portion has a third diameter. The second expansion tool further includes a third pilot portion being generally parallel to the second pilot portion. The third pilot portion has a fourth diameter that is larger than the third diameter. The second expansion tool further includes a forming portion bridging the second pilot portion and the third pilot portion and a second expansion portion having a fifth diameter. The fifth diameter is larger than the third diameter. The second expansion tool further includes a second land bridging the forming portion and the second expansion portion. The axial distance from the first end of the first expansion tool to the first land is generally the same as the axial distance from the first end of the second expansion tool to the forming portion, the second expansion tool being configured to be used subsequent to the first expansion tool.
(34) The process shown in
(35) As shown in the illustrated embodiments of
(36) Notably, the second and third expansion tools 14 and 106 include a first pilot portion 34, 112 and a second pilot portion 38, 138 that are substantially parallel to one another and to the main sidewalls of the container. The first pilot portion 34, 112 has generally the same diameter as the initial diameter 26 of the container 18a (e.g., the unexpanded portion 114 of the final container 18e) such that, when the first pilot portion 34, 112 is inserted into the container, it guides, but does not further expand the container near the end of the expansion stroke. The second pilot portion 38, 138 has generally the same diameter as the expanded portion 30 formed during the preceding process step by the preceding expansion tool. As such, the container is maintained in a generally centralized position throughout the expansion process.
(37) In the embodiment of
(38) The embodiments described herein provide various advantages over conventional expansion processes and apparatus. For example, in conventional expansion processes and apparatus, the pilot portion of a subsequent expansion tool does not provide any benefit to a previously partially expanded container until the pilot portion comes into contact with the interior of the container that has not been expanded. In the embodiments described herein, on the other hand, the second pilot portion positioned just prior to the expansion portion provides for constant piloting and guidance of the container such that the container is not positioned off center with respect to the expansion tool during the expansion operation. Thus, improved concentricity is achieved between expansion operations, especially for deep forming in which the forming process is performed over generally the entire length of the container (or from as close to the bottom as possible up through or near the top of the container). As such, the container sidewall material is less likely to undesirably thin or thicken, which may lessen defects or splitting of the material. Moreover, the resulting surface of the expanded container is generally smoother and includes fewer (if any) visual defects. The embodiments described herein also provide the ability to use an expansion portion having a smaller diameter compared with a larger finishing diameter, which may allow for a larger rate of expansion that applies less stress to the container material.
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(40) The articles described herein may be processed through any number of stages, one or more of which may be a diameter expansion stage. When all process/forming stages are complete, the article is discharged from the machine. The expansion mechanisms described herein may be part of a machine line such as a recirculated machine line or any other type of machine line.
(41) An expansion mechanism may be a separate machine, or the expansion mechanism may be one machine in a machine line. One example of a machine line that may be used with the embodiments described herein is described in U.S. Pat. No. 7,963,139, which is hereby incorporated by reference in its entirety. Referring to the machine line 250 of
(42) According to one embodiment, an expansion process includes feeding an article into a continuously rotating turret, as disclosed in U.S. Pat. No. 7,963,139. The article is loaded into a forming station, and an expansion tool is inserted into an open end of the article. The expanding tool is withdrawn, and the article is transferred to another turret, discharge track, or to another apparatus. As described in detail above, a portion of the expanding tool has a diameter greater than the diameter of at least a portion of the article.
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(44) Referring back to
(45) The cans 205 may be held in position on this first transfer star wheel using a pneumatic pressure differential or “suction” as it will be referred to.
(46) The cans are then passed from the first transfer star wheel to a first turret star wheel and enter into the can expansion forming process on the can expansion machine. While the invention is not so limited, embodiments of the invention may comprise expansion machines constructed as modules. The use of can expansion modules allows for the machine line 250 to be assembled/changed to provide as many can expansion stages as is required and to allow for the addition of additional stages such as flanging, necking, trimming, curling, threading, and/or base reforming/reprofiling, which may be added/removed as desired.
(47) While the invention is susceptible to various modifications and alternative forms, specific embodiments and methods thereof have been shown by way of example in the drawings and are described in detail herein. It should be understood, however, that it is not intended to limit the invention to the particular forms or methods disclosed, but, to the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention.