1. Field of the Invention
The invention relates generally to can ends and, more particularly, to a can end scoring method. The invention also relates to tooling assemblies for scoring can ends. The invention further relates to conversion presses for providing scored can ends.
2. Background Information
Metallic containers (e.g., cans) for holding products such as, for example, food and beverages, are typically provided with an easy open can end on which a pull tab is attached (e.g., without limitation, riveted) to a tear strip or severable panel. The severable panel is defined by a scoreline in the exterior surface (e.g., public side) of the can end. 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 can.
When the can end is made, it originates as a can end shell, which is formed from a sheet metal product (e.g., without limitation, sheet aluminum; sheet steel). The shell is then conveyed to a conversion press, which 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, tab securing and tab staking, are performed until the shell is fully converted into the desired can end and is discharged from the press. Typically, each tool station of the conversion press includes an upper tool member, which is structured to be advanced towards a lower tool member upon actuation of a press ram. The shell is received between the upper and lower tool members. Thus, as the upper tool member engages the shell, the upper and/or lower tool members respectively act upon the public and/or product (e.g., interior side, which faces the can body) sides of the shell, in order to perform a number of the aforementioned conversion operations. Upon completion of a given operation, the press ram retracts the upper tool member and the partially converted shell is moved to the next successive tool station, or the tooling is changed within the same station, to perform the next conversion operation.
As shown in
There is, therefore, room for improvement in can end scoring methods, and in tooling assemblies and conversion presses for providing scored can ends.
These needs and others are met by embodiments of the invention, which are directed to a tooling assembly and an associated method for substantially simultaneously forming a depression (e.g., recessed area; channel; indentation) in a can end, and a scoreline within the depression. As a result of the scoreline being disposed in the depression, the scoreline can be effectively and efficiently completely coated by a suitable post score sealant or repair agent, which may be applied to the can end.
As one aspect of the invention, a tooling assembly is provided for scoring a can end. The can end comprises a scoreline defining a severable panel. The tooling assembly comprises: a first tool member; and a second tool member disposed opposite the first tool member, the second tool member being structured to cooperate with the first tool member in order to create a depression in the can end and to form the scoreline within the depression.
The first tool member may be a score knife, and the second tool member may be a score anvil. The can end may further comprise a first portion, a second portion and a third portion, and the score anvil may include a first support surface structured to support the first portion of the can end, a second support surface structured to support the second portion of the can end, and a cavity disposed between the first support surface and the second support surface beneath the third portion of the can end. The score knife may be structured to depress the third portion of the can end into the cavity of the score anvil in order to form the depression of the can end. The can end may further comprise a periphery, wherein the depression comprises a channel extending around the can end proximate the periphery, and wherein the scoreline is a peripheral scoreline extending around the can end within the channel. The can end may further comprise a first side and a second side disposed opposite the first side. The cavity of the score anvil may have a base, wherein the score knife is structured to engage the first side of the can end and to depress the can end into the cavity of the score anvil until the second side of the can end engages the base of the cavity. When the second side of the can end engages the base of the cavity, the score knife may be structured to score the first side of the can end, thereby forming the scoreline. The score knife may have a vertical axis, and the base of the cavity of the score anvil may have a center, wherein the vertical axis of the score knife is aligned with the center of the base of the cavity.
The scoreline of the can end may include an apex, a first edge and a second edge, wherein the apex of the scoreline is disposed between the first side of the can end and the second side of the can end, and wherein the first edge of the scoreline and the second edge of the scoreline are disposed at the first side of the can end. The first side of the first portion of the can end and the first side of the second portion of the can end may be disposed in a common plane, wherein the first edge of the scoreline and the second edge of the scoreline are disposed within the depression of the can end and below such common plane.
As another aspect of the invention, a conversion press is provided. The conversion press is structured to convert a can end shell into a can end. The can end comprises a scoreline defining a severable panel. The conversion press comprises: a press ram; at least one tool station; and a tooling assembly coupled to a corresponding one of the at least one tool station, the tooling assembly comprising: a first tool member, and a second tool member disposed opposite the first tool member. The press ram is structured to advance at least one of the first tool member and the second tool member toward the other of the first tool member and the second tool member. Responsive to the press ram advancing the at least one of the first tool member and the second tool member toward the other of the first tool member and the second tool member, the first tool member is structured to cooperate with the second tool member in order to create a depression in the can end and to form the scoreline within the depression.
The at least one tool station may be a first tool station and at least a second tool station. The first tool member and the second tool member may be coupled to the tooling assembly of the first tool station. The tooling assembly of the first tool station may be structured to substantially simultaneously form the depression in the can end and to form the scoreline within the depression.
As another aspect of the invention, a method of scoring a can end comprises: inserting a can end shell between opposing tool members of a tooling assembly within a tool station of a conversion press; advancing at least one of a first tool member and a second tool member toward the other of the first tool member and the second tool member, in order to at least partially convert the can end shell into a can end; forming a depression in the can end; and forming a scoreline within the depression of the can end.
The method may further comprise: engaging a first side of the can end with the score knife, supporting at least a portion of a second side of the can end with the score anvil, depressing the can end into a cavity of the score anvil in order to form the depression of the can end, and scoring the first side of the can end within the depression to form the scoreline of the can end. Forming the depression and forming the scoreline may be performed substantially simultaneous within the same tool station of the conversion press.
The method may further comprise: applying a sealant to the scoreline. The sealant may form a pool within the depression of the can end, thereby completely covering the scoreline disposed within the depression.
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:
For purposes of illustration, embodiments of the invention will be shown and described as applied to the peripheral scoreline that defines the severable panel of a circular can end having a safety fold, although it will be appreciated that they could also be applied to provide any known or suitable scoreline other than the peripheral scoreline (e.g., without limitation, a mustache scoreline; a tear strip scoreline) for circular or non-circular can ends, with or without a suitable configuration of safety folds.
Directional phrases used herein such as, for example, upper, lower, above, below 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 employed herein, the statement that two or more parts are “coupled” together shall mean that the parts are joined together either directly or joined through one or more intermediate parts.
As employed herein, the term “can” refers to any known or suitable container, which is structured to contain a substance (e.g., without limitation, liquid; food; any other suitable substance), and expressly includes, but is not limited to, food cans, such as easy open food cans.
As employed herein, the term “can end” refers to the closure that is structured to be coupled to the can, in order to seal the can.
As employed herein, the term “can end shell” is used substantially interchangeably with the term “can end.” The “can end shell” or simply the “shell” is the member that is acted upon and is converted by the disclosed tooling assembly and conversion press to provide the desired can end.
As employed herein, the term “sealant” refers to any known or suitable liquid, lacquer or other suitable coating (e.g., without limitation, repair agent), which is applied to the can end after it has been scored, in order to cover and protect (e.g., seal) the scoreline of the can end.
As employed herein, the term “depression” shall mean a recessed area (e.g., without limitation, channel; indentation) in the can end within which the scoreline is made, wherein the depression is structured to hold (e.g., pool; collect) sealant so that the sealant completely covers the scoreline.
As employed herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).
Continuing to refer to
Accordingly, among other benefits, the disclosed depression 118 collects sealant 119 such that it covers not only the first and second edges 121,123 of the scoreline 117, but also a corresponding portion of the public side 113 of the can end 101 adjacent each of the scoreline edges 121,123. In addition, the resultant pool of sealant 119 is substantially flush with respect to the common plane 147 of the first and second portions 125,127 of the can end 101, as shown. In other words, the undesirable protruding and unsightly volume of sealant (see, for example, the convex shape of the excessive volume of sealant 19′ in
The scoreline 117 in the example of
Having now described an illustrative example of the can end 101, which is formed in accordance with an embodiment of the invention,
A conversion press 200, which is utilized to perform the conversion operations is partially shown in
Movement of the first (e.g., upper from the perspective of
Accordingly, it will be appreciated that the conversion press 200 may have any known or suitable number and/or configuration of tool stations (e.g., 107) structured to perform any variety of desired operations such as, for example and without limitation, rivet forming, panel forming, scoring, embossing and/or final staking. The rivet forming operation, for example, and the corresponding tooling to effectuate the same, may utilize integral rivet development technology similar to that which is shown and described in U.S. Pat. Nos. 5,749,257; 5,755,134; and 5,851,685, which are hereby incorporated herein by reference. Additional non-limiting examples of tool stations (not shown), which could be employed to perform the foregoing operations are described, for example, in U.S. Pat. No. 7,270,246, which has been incorporated herein. It will also be appreciated that such tooling operations can be performed within a single conversion press (e.g., 200), wherein the upper and lower tooling 205,207 of the conversion press 200 is interchanged between conversion operations, or as separate portions or tool stations of the same press 200. Alternatively, any suitable number and/or configuration of separate presses (not shown) could be employed, one for each tool station.
As will now be described with reference to
The score knife 109 is structured to depress the third portion 129 of the can end shell 101′ into the cavity 135 of the score anvil 111, in order to form the depression 118 of the can end 101. More specifically, when the upper tool member 103 is advanced towards the lower tool member 105, as indicated by arrow 108 of
More specifically, a conversion operation such as the one employed to form (e.g., bend the shell 101′) the exemplary depression 118 would typically be performed in another, different tool station (not shown), which is separate from the scoring operation. However, in accordance with the invention, both operations are performed in the same tool station 107 (
It will be appreciated that the particular shape of the score knife 109 is not intended to be a limiting aspect of the invention. For example and without limitation, a generally right-angled triangular score knife (not shown) could be employed. Such a score knife is disclosed, for example, in U.S. Pat. No. 5,462,396, which is hereby incorporated herein by reference. It will also be appreciated that the cavity 135 of the score anvil 111 could have any known or suitable alternative shape and/or configuration other than that which is shown and described, in order to provide the desired can end depression (e.g., 118). Specifically, although the first and second support surfaces 131,133 of the example score anvil 111 are disposed in a common plane 139, this need not necessarily be the case. Additionally, the score anvil cavity 135 has a depth 141 measured between the common plane 139 and the base 134 of the cavity. The particular shape and dimensions (e.g., without limitation, depth 141) of the cavity 135 are not meant to be limiting aspects of the invention. It is the precise alignment of the score knife 109 with the desired portion (e.g., center 145) of the score anvil cavity 135, as well as the fact that the scoreline 117 and depression 118 of the can end shell 101′ are formed substantially simultaneously, which is advantageous. Specifically, these aspects of the invention decrease the likelihood of undesirable excessive strain on the product side 115 of the can end shell 101′ during the formation of the depression 118 and the scoreline 117, which is disposed therein. Accordingly, an additional benefit of the disclosed tooling assembly 100 and associated method is that the potential for undesirable strain-induced metal exposure on the product side 115 of the can end shell 101′ is substantially eliminated.
In view of the foregoing, it will be appreciated that the disclosed conversion press (
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 the invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.