JP7294831B2 - Method for manufacturing a container lid with a metal shell provided with decorative embossments - Google Patents

Description

The present invention relates to a method for manufacturing a container lid with a metal shell, the top wall of which is provided with decorative embossments consisting of letters and/or figures.

As disclosed in Patent Documents 1 and 2 below, as an easy-to-open container lid for a container made of glass, synthetic resin, or metal for soft drinks or alcoholic beverages, a circular top wall, the top wall It includes a skirt wall hanging down from the peripheral edge and an extension piece extending from the lower end of the skirt wall. A container lid having a metal shell in which a pair of arcuately extending scores are formed in a boundary region between a skirt wall and a skirt wall is widely used. As disclosed in Patent Document 2 below, a synthetic resin liner is normally provided on the inner surface of the top wall, and a synthetic resin grip ring is connected to the extending piece. Patent Document 2 below further discloses a method for manufacturing a container lid as described above, in which a pair of scores is formed at a predetermined portion of a thin metal plate, and then punching and drawing are applied to the thin metal plate to form a metal shell. After completion, the extension piece of the metal shell is insert-molded as a so-called core to form a synthetic resin holding ring, which is connected to the extension piece, and further synthesized with the inner surface of the top wall of the metal shell. Forming a resin liner is also disclosed.

JP-A-64-53724 JP 2011-173594 A

Recently, therefore, in order to make the appearance of the container lid more attractive and also to prevent counterfeiting of the container lid for counterfeit products, the top wall of the metal shell has letters and letters. There is a demand to form decorative embossments (ie decorative recesses and/or protrusions) that are/or consist of graphics. However, it is not always easy to form decorative embossing on the top wall of the metal shell in response to such a request. (2) the formed decorative embossing is damaged during the formation of the synthetic resin liner or during the transportation of the container lid; It is important to solve problems such as the deterioration of the sealing properties of synthetic resin liners due to their presence.

The present invention has been made in view of the above facts, and its main technical problem is to be able to form a desired decorative embossment on the top wall of a metal shell without abusing and degrading the score. , to provide a new and improved method for manufacturing a container lid having a metal shell with decorative embossments made up of letters and/or graphics on the top wall.

In addition to solving the above main technical problems, another technical problem of the present invention is to prevent the decorative embossing formed on the top wall of the metal shell from being damaged during the formation of the synthetic resin liner. To provide a new and improved method for manufacturing a container lid provided with a metal shell having decorative embossments composed of letters and/or figures on the top wall.

Still another technical object of the present invention, in addition to solving the main technical object described above, is to prevent deterioration of the sealing properties of the synthetic resin liner due to the existence of the decorative embossment, and to prevent the deterioration of the sealing characteristics of the synthetic resin liner, and and/or to provide a new and improved method of manufacturing a container closure having a metal shell in which a decorative embossment composed of graphics is disposed.

As a result of intensive studies and experiments, the present inventors formed a pair of scores at predetermined positions on the thin metal plate after forming decorative embossing at predetermined positions on the thin metal plate, and then performed stamping and drawing on the thin metal plate. In addition, the inventors have found that the above main technical object can be achieved by completing the metal shell.

In addition, the above other technical problems can be achieved by forming the decorative embossing by forming recesses instead of protrusions in the portion of the thin metal plate that defines the outer surface of the top wall, and that the liner is In the case of a form having a central portion and a peripheral seal portion, a recess having a depth smaller than the thickness of the central portion of the liner at a portion defining the outer surface of the top wall of the thin metal plate and corresponding to the central portion of the liner. It has been found that the above still another technical object can be achieved by forming a decorative embossment by forming a.

That is, according to the present invention, as a method for achieving the above main technical problems,
It includes a circular top wall, a skirt wall hanging down from the peripheral edge of the top wall, and an extension piece extending from the bottom end of the skirt wall, and the top wall is provided with decorative embossed letters and/or figures. In the top wall and the skirt wall, the skirt wall extends upward from both sides of the extension piece, and then extends in an arc from the peripheral edge region of the top wall to the boundary region between the top wall and the skirt wall. A method of manufacturing a container lid having a metallic shell having a pair of scores formed thereon, comprising:
an embossing step of forming the decorative embossing at a predetermined position of the thin metal plate;
After the embossing step, a score forming step of forming the pair of scores at predetermined positions on the metal sheet, and after the score forming step, punching and drawing are applied to the metal sheet to complete the shell. punching and drawing process,
A method is provided comprising:

The container lid comprises a synthetic resin liner disposed on the inner surface of the top wall of the shell, and includes a liner forming step of forming the liner on the inner surface of the top wall after the punching and drawing steps. is convenient. In a preferred form, the container lid comprises a synthetic resin gripping ring connected to the extension piece, and after the liner forming step, or after the stamping and drawing step and before the liner forming step. A ring forming step for forming a gripping ring is included. The above-mentioned other technical object is achieved by forming the decorative embossing in the embossing step by forming recesses in the portion of the thin metal plate that defines the outer surface of the top wall. Still another technical problem is that the liner has a central portion and a peripheral seal portion, and in the embossing step, a portion of the thin metal plate defining the outer surface of the top wall and the central portion of the liner. This is achieved by forming the decorative embossing by forming a recess having a depth smaller than the thickness of the central portion of the liner at a portion corresponding to the portion.

In the method of the present invention, since a pair of scores are formed at predetermined positions on the thin metal plate after the decorative embossing is formed at predetermined positions on the thin metal plate, the scores on the top surface wall of the metal shell are not abused and deteriorated. , can form the required decorative embossing.

Furthermore, since the decorative embossing is formed by forming recesses in the metal thin plate at the portion that defines the outer surface of the top wall, the decorative embossing formed on the top wall of the metal shell may be used when forming the synthetic resin liner or The container lid is not damaged during transportation (in the case of forming a decorative embossment by forming a convex portion on a thin metal plate that defines the outer surface of the top wall, when forming a synthetic resin liner In addition, the convex portion defining the decorative embossing may be pressed against the base supporting the top wall, or the convex portion defining the decorative embossing may rub against the conveying guide when the container lid is conveyed, and the decorative embossing may be damaged. ). Furthermore, in the case where the liner has a central portion and a peripheral seal portion, in the embossing step, the central portion of the liner is placed in a portion corresponding to the central portion of the liner and which defines the outer surface of the top wall of the thin metal plate. Since the decorative embossment is formed by forming a recess having a depth smaller than the thickness of the liner, the peripheral seal portion of the liner may be adversely affected by the formation of the decorative embossment, degrading the sealing properties of the synthetic resin liner. do not have.

The top view which shows the typical example of the container lid manufactured by the method of this invention. 2 is a cross-sectional view along line II-II of FIG. 1; FIG. FIG. 2 is a cross-sectional view along line III-III of FIG. 1; A simplified diagram for explaining the hole forming step in a preferred embodiment of the method of the present invention. A simplified diagram for explaining the embossing step in a preferred embodiment of the method of the present invention. A simplified diagram for explaining the score formation step in a preferred embodiment of the method of the present invention. 1 is a simplified diagram for explaining the stamping and drawing steps in a preferred embodiment of the method of the present invention; FIG. 4 is a simplified diagram illustrating the liner forming step in a preferred embodiment of the method of the present invention; FIG. 4 is a simplified diagram illustrating the gripping ring forming step in a preferred embodiment of the method of the present invention; FIG.

Preferred embodiments of the method of the present invention will now be described in detail with reference to the accompanying drawings.

First, a typical example of a container lid manufactured by the method of the present invention will be described with reference to FIGS. 1 to 3. FIG. The container lid, generally designated 2, includes a metal shell 4 formed from a suitable sheet metal such as an aluminum-based alloy sheet, a chromated steel sheet or a tinplate sheet. The shell 4 includes a circular top wall 6, a skirt wall 8 hanging down from the periphery of the top wall 6, and an extension piece 10 (see FIG. 7) extending from the lower end of the skirt wall 6 at a specific portion in the circumferential direction. I'm in. Approximately triangular cutouts 12a and 12b are formed in the lower end portion of the skirt wall 8 on both sides of the extending piece 10 in the circumferential direction. The shell 4 is also formed with a pair of scores 14a and 14b. Each of the scores 14a and 14b extends upward through the skirt wall 8 from the cutouts 12a and 12b (that is, from both sides of the extension piece 10), and then extends from the peripheral area of the top wall 6 to the area between the top wall 6 and the skirt wall 8. Extends in an arc across the boundary area. The scores 14a and 14b can also be formed by applying a tool to the outer surface of the shell 4 to locally reduce the wall thickness, or by applying a tool to the inner surface of the shell 4 (thus, the inner surface of the shell 4). Advantageously, it is formed by locally reducing the wall thickness (by forming grooves on the sides). A pair of holes 16 are formed at the tip of the extension piece 10 (see FIG. 7).

A synthetic resin liner 18 made of an appropriate synthetic resin such as soft polyethylene is disposed on the inner surface of the top wall 6 of the shell 4 . The generally disc-shaped liner 18 has a relatively thin central portion 20 and a relatively thick peripheral seal portion 22 . A pair of downwardly projecting annular seals, that is, an inner annular seal 24 and an outer annular seal 26 are formed in the peripheral edge seal portion 22 . A grip ring 28 made of suitable synthetic resin such as polypropylene or polyethylene is connected to the tip of the extension piece 10 . If desired, the formation of the synthetic resin gripping ring 28 can be omitted and the extension piece 10 of the metal shell 4 itself can be formed in the shape of a gripping ring having the required dimensions.

Since the configuration of the illustrated container lid 2 as described above is well known to those skilled in the art, detailed description thereof will be omitted.

Therefore, in the container lid 2 manufactured by the method of the present invention, the top wall 6 of the shell 4, more specifically, the area inside the pair of scores 14a and 14b on the top wall 6 of the shell 4 is provided with decorative embossments (concave and/or convex portions for decoration) 30 composed of letters and/or graphics. In the illustrated embodiment, the decorative embossment 30 is formed of an N-shaped recess on the outer surface of the top wall 6 . As can be clearly understood by referring to FIG. 2, the outer edge of the concave portion forming the decorative embossment 30 is 30 to 60 degrees with respect to the central axis of the shell 4 in terms of ease of molding and improvement of decorativeness. is preferably inclined at an angle α of In addition, in order to reliably avoid damage to the sealing effect of the synthetic resin liner 18 on the mouth/neck portion of the container due to the formation of the decorative embossments 30, the recesses defining the decorative embossments 30 are synthetically formed in the top wall 6. It is formed at a portion of the resin liner 18 corresponding to the central portion 20 located inside the peripheral seal portion 22, and the depth d of the recess is smaller than the thickness t of the central portion 20 of the synthetic resin liner 18. is preferred. Although the decorative embossments can be formed from the convex portions formed on the outer surface of the top wall 6, in this case, as will be further described later, when the synthetic resin liner 18 is formed on the inner surface of the top wall 6, the decorative embossments 30 are formed. may be damaged.

A preferred embodiment of the method of the invention for manufacturing a container lid 2 as described above will now be described.

Hole Forming Step Referring to FIG. 4, first, a thin metal plate 32 for forming the shell 4 is prepared. The metal sheet 32 may be an aluminum-based alloy sheet, a chromate-treated steel sheet, or a tin plate, and in the case of an aluminum-based alloy sheet, the thickness is preferably about 0.15 to 0.25 mm. The front and back surfaces of the thin metal plate 32 may be coated with a known suitable protective coating or coloring coating. In the illustrated embodiment, a pair of holes 16 are formed in the metal sheet 32 at desired locations. If desired, the formation of such holes 16 can be performed at any time after the embossing steps described below and before the stamping and drawing steps.

Emboss Forming Step Next, as shown in FIG. 5, recesses (and/or protrusions) that constitute the decorative embossments 30 are formed at predetermined positions of the thin metal plate 32 . When the decorative embossing 30 is composed of recesses, a processing tool having a tip shape corresponding to the recesses is applied to the surface of the thin metal plate 32 placed on a support base (not shown) to form the recesses. can be formed.

Score Forming Step After that, as shown in FIG. The formation of the scores 14a and 14b can be accomplished by forming grooves on the back surface (inner surface) or front surface (outer surface) of the metal sheet 32 with a tool. It is convenient to define this by locally reducing the thickness by forming grooves in the inner surface of the top wall 6 of the metal shell 4 by applying a tool to the inner surface of the top wall 6 of the metal shell 4 . Therefore, in the method of the present invention, it is important to carry out the score forming step after the embossing step and before the punching and drawing steps described below. According to the experience of the present inventors, when performing the embossing step after forming the scores 14a and 14b, the recesses (and/or protrusions) constituting the decorative embossments 30 are already formed. The scores 14a and 14b that are being treated are abused (in other words, the scores 14a and 14b are adversely affected), the scores 14a and 14b are degraded (i.e. partially damaged or excessively weakened), resulting in As a result, the opening properties of the container lid 2 tend to deteriorate or become unstable, and the sealing properties tend to deteriorate.

Punching and drawing process Following the score forming process, a punching and drawing process is performed. In this punching and drawing process, as shown in FIG. 7, the thin metal plate 32 is punched and drawn to complete the shell 4 . The stamping and drawing can be performed substantially simultaneously, or the stamping can be performed followed by the drawing.

Liner Forming Step Next, as shown in FIG. 8, a liner forming step is performed to form a synthetic resin liner 18 on the inner surface of the top wall 6 of the shell 4 . In this liner forming step, the shell 4 is placed on a support base (not shown) in an inverted state (that is, with the outer surface of the top wall 6 in contact with the support base). Then, it is convenient to supply a softened or molten synthetic resin material to the inner surface of the top wall 6 and apply a stamping tool to the synthetic resin material to stamp the synthetic resin liner 18 . At this time, if the decorative embossing 30 is formed of concave portions, the concave portions do not come into contact with the support base and thus the decorative embossing is not damaged, but the decorative embossing 30 is formed of convex portions. In this case, the molding pressure is applied while the projections are in contact with the support base, so there is a risk that the decorative embossments 30 will be damaged.

Ring Forming Step In the illustrated embodiment, after the liner forming step described above, a ring forming step is performed as shown in FIG. In this ring forming step, the ring is compressed or injection molded using the extended piece 10 of the shell 4 as a core to form the gripping ring 28, and the gripping ring 28 is connected to the tip of the extending piece 10, Thus, the container lid 2 is completed. If desired, a ring forming step can be performed after the stamping and drawing steps and before the liner forming step.

In the above description, the manufacture of one shell 4 has been described, but in actual industrial manufacturing, a relatively large-sized thin metal plate is prepared, and a plurality of holes and embossing steps are performed on the thin metal plate. , the score forming step and the punching and drawing steps can be performed simultaneously in sequence to form a plurality of shells 4 at the same time.

The hole forming process, the score forming process, the punching and drawing process, the liner forming process and the ring forming process per se are well known to those skilled in the art, and therefore detailed descriptions of these processes are omitted in this specification. . Also, the method of using the container lid 2 manufactured by the method of the present invention, that is, the method of attaching it to the mouth and neck of the container to seal the mouth and neck of the container, and the manner of detaching from the mouth and neck of the container to open the mouth and neck of the container. Since the manner of doing so is also a well-known matter, a description thereof will be omitted in the present invention.

2: Container lid 4: Metal shell 6: Top wall 8: Skirt wall 10: Extension piece 12a: Notch 12b: Notch 14a: Score 14b: Score 16: Hole 18: Synthetic resin liner 20: Synthetic resin liner Center Part 22: Peripheral Seal of Synthetic Resin Liner 24: Inner Annular Seal 26: Outer Annular Seal 28: Grip Ring 30: Decorative Embossment 32: Metal Sheet

Claims (5)

It includes a circular top wall, a skirt wall hanging down from the periphery of the top wall, and an extension piece extending from the bottom end of the skirt wall, and the top wall is provided with decorative embossed letters and/or figures. In the top wall and the skirt wall, the skirt wall extends upward from both sides of the extension piece and then extends in an arc from the peripheral edge region of the top wall to the boundary region between the top wall and the skirt wall. A method of manufacturing a container lid having a metallic shell having a pair of scores formed thereon, comprising:
an embossing step of forming the decorative embossing at a predetermined position of the thin metal plate;
After the embossing step, a score forming step of forming the pair of scores at predetermined positions on the metal sheet, and after the score forming step, punching and drawing are applied to the metal sheet to complete the shell. punching and drawing process,
A method comprising: The container lid has a synthetic resin liner provided on the inner surface of the top wall of the shell,
A liner forming step of forming the liner on the inner surface of the top wall after the punching and drawing steps,
The method of claim 1. The container lid comprises a synthetic resin gripping ring connected to the extension piece,
after the liner forming step, or after the stamping and drawing step and before the liner forming step, forming the gripping ring;
3. The method of claim 2. In the embossing step, the decorative embossing is formed by forming a recess in a portion of the thin metal plate that defines the outer surface of the top wall.
4. A method according to any one of claims 1-3. the liner has a central portion and a peripheral seal portion;
In the embossing step, the center portion of the liner is formed in a region inside the pair of scores and corresponding to the center portion of the liner at a portion defining the outer surface of the top wall of the thin metal plate. forming the decorative embossment by forming a recess having a depth less than the thickness of
3. The method of claim 2.

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