JP5501398B2 - Manufacturing method of cap with inner plug - Google Patents

Description

  The present invention relates to a method of manufacturing a cap having an inner plug, and more specifically, a method of manufacturing a cap that can smoothly insert the inner plug into the cap shell and reliably prevent the inserted inner plug from being detached. About.

In general, metal caps obtained by molding and processing metal thin plates such as aluminum and tin have much better gas barrier properties than plastic caps, and are firmly fixed to the container mouth by screw engagement. Therefore, it is widely used as a cap for containers such as carbonated drinks.
Conventionally, as a metal cap, by supplying molten resin directly into the metal cap shell and compression molding, a one-piece cap etc. that is molded by simultaneously forming and arranging the liner in the cap shell is practical. It is provided.

  However, in the one-piece type metal cap, when the tamper evidence band is formed, the sealing performance of the cap may be released before the bridge connecting the tamper evidence band is broken, and this Such a one-piece type metal cap has a problem that the opening torque is larger than that of the two-piece cap, and the unsealing property is inferior.

As a solution to such a problem, a sheet metal body having a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall, a sheet metal reinforcing member, and a synthetic resin liner are provided. The reinforcing member has a circular wall, the liner is disposed on the lower surface of the circular wall, and the skirt wall of the main body is formed with an inner protrusion protruding inward in the radial direction. The free end of the reinforcing member is engaged with the inner projecting portion so that the circular wall of the reinforcing member is positioned facing the inner surface of the top wall of the main body. A container lid characterized by being constrained inside has been proposed (Patent Document 1).
This container lid integrates a metal panel (reinforcing member) and liner and inserts it into a metal cap shell (main body), or supplies molten resin after inserting the metal panel into the cap shell. However, it is formed by a method of embossing this.

Japanese Patent No. 4585126

Although the said container lid solves the problem of the conventional metal cap mentioned above, it has the following problems.
That is, when placing the metal panel in the metal cap shell, if the outer diameter of the metal panel is reduced in order to facilitate the insertion of the metal panel, the inner plug will be metal when the container is decompressed. If the outer diameter of the metal panel is increased in order to prevent the inner plug from being detached from the cap shell and remaining in the container mouth portion or being unable to be resealed, There is a risk that the metal panel or the metal cap shell may be deformed when the is inserted into a predetermined position in the upper part of the metal cap shell.
Accordingly, an object of the present invention is to easily insert the inner plug (reinforcing member) at a predetermined position in the upper part of the cap shell without causing deformation of the inner plug or the cap shell, and the container is in a decompressed state. It is also an object of the present invention to provide a method of manufacturing a cap having an inner plug with an outer diameter that does not leave the predetermined position above the cap shell.

According to the present invention, a cap shell comprising a top plate portion and a skirt portion, and a screw forming region formed in the skirt portion, a metal panel, and an inner plug having a resin liner on the inner surface side of the metal panel, In the method of manufacturing the cap with an inner plug, the inner plug is placed inside the upper part of the skirt by expanding the outer peripheral edge of the metal panel after the metal panel is inserted into the cap shell. Provided is a method of manufacturing a cap with an inside plug, which is held by a formed support portion so that it cannot be detached from the cap shell and is movable up and down at a predetermined position above the support portion.
In addition, according to the present invention, a cap shell comprising a top plate portion and a skirt portion, and having a screw forming region formed in the skirt portion, a metal panel, and a resin liner on the inner surface side of the metal panel are provided. In the manufacturing method of the cap with an inner plug comprising the plug, the inner plug is inserted into the cap shell of the metal panel at the same time as the outer peripheral edge of the metal panel is expanded, so that the inner plug There is provided a method for manufacturing a cap with an inside plug, which is held by a support portion formed on the inner side so as not to be detached from the cap shell and movable up and down at a predetermined position above the support portion.

According to the manufacturing method of the cap of the present invention,
1. When the inner plug integrally molds the resin liner and the metal panel by compressing the molten resin on the inner surface side of the metal panel, the outer peripheral edge of the metal panel is expanded.
2. Expanding the metal panel at the same time as inserting the metal panel into the cap shell,
3. The cap shell is made of metal, and a plurality of openings are formed in the upper end portion of the skirt portion at intervals in the circumferential direction. A radius of a lower region along a cutting line engraved in the skirt portion is formed in the opening. The support part is formed by protruding inward in the direction;
4). The shape of the tip surface of the pressing sleeve that presses the outer peripheral edge of the metal panel is the same shape as the shape of the metal panel at the portion where the metal panel after being expanded and the tip surface abuts. Being
Is preferred.

In the manufacturing method of the cap with an inner cap of the present invention, the metal panel can be inserted and arranged at a predetermined position in the upper part of the cap shell without being deformed, and then expanded to increase the outer diameter. Even if the inside of the container is in a reduced pressure state, the inner stopper does not come off from a predetermined position in the cap shell.
In the manufacturing method of the present invention, the outer diameter of the metal panel can be increased simultaneously with the insertion of the metal panel into the cap shell or simultaneously with the molding of the liner. Also excellent.
Furthermore, depending on the manufacturing method of the present invention, the metal panel shape of the portion where the metal panel after the shape of the front end surface of the pressing sleeve pressing the outer peripheral edge of the metal panel is expanded and the front end surface abuts is formed. The shape after the metal panel is expanded can be stably formed.
The cap having a metal panel obtained by the production method of the present invention has a separate metal panel on the top plate portion, so that it is possible to reduce the opening torque required for opening, even for elderly people and female children. Can be easily opened with light force.
The cap having a metal panel obtained by the production method of the present invention has a metal panel on the top plate part, and thus has excellent gas barrier properties. Gas content such as alteration of contents due to oxygen permeation or carbonated beverages is outside the container. Escape is effectively prevented.

It is a figure which shows an example of the metal cap which has an inner stopper shape | molded by the manufacturing method of this invention. It is a figure for demonstrating the manufacturing method of this invention. It is a figure which expands and shows the principal part of the metal caps shown in FIG. 2B. It is a figure explaining an opening process in the state where the metal cap shown in FIG. 1 was applied to the container. It is a figure which shows an example of the resin caps with an inner cap shape | molded by the manufacturing method of this invention.

The present invention will be described with reference to the accompanying drawings.
In FIG. 1 showing an example of a cap having an inner plug manufactured by the manufacturing method of the present invention, the metal cap represented as a whole by 1 is an inner plug composed of a metal cap shell 2, a metal panel 3 and a liner 4. It consists of five.
Generally speaking, the metal cap shell 2 includes a circular top plate portion 20 and a substantially cylindrical skirt portion 21, and the skirt portion 21 includes an upper main portion and a weakened portion 22 formed at the lower end of the main portion. The lower tamper evidence band 23 is formed integrally therewith.
In the central portion of the top plate portion 20, a recess 24 that is recessed toward the container is formed for positioning with the inner plug 5. The main part of the skirt portion 21 has a screw forming region. Above that, a plurality of openings 25, 25... Are formed at intervals in the circumferential direction, and a cutting line 26 engraved in the skirt portion 21 when the openings 25, 25. , 26... Are projected inward in the radial direction, and the opening edge 28 (upper side of the lower area 27) serves as a support portion and the outer edge of the metal panel 3. 33 is locked and the metal panel 3 can be held in the cap shell 2 so as not to be detached.

The metal panel 3 constituting the inner plug 5 is made of a metal flat plate, but the central portion 31 is recessed toward the container side in the same manner as the shape of the top plate portion 20 of the cap shell 2. That is, the metal panel 3 can be positioned in the cap shell 2 by this similar shape, and the liner 4 and the metal panel 3 can be easily formed and expanded later. The outer peripheral edge 32 has a shape curved downward so that the outer edge 33 faces downward, and the lower surface of the metal panel 3 is the inner surface.
As described above, the metal panel 3 is supported so as not to be detached from the cap shell 2 by locking the outer edge 33 with the opening edge (that is, the support portion) 28 of the opening 25 of the cap shell 2 as described above. Yes.
Further, a liner 4 is integrally formed on the inner surface (side surface of the container) of the metal panel 3, and the liner 4 is positioned on the inner side of the seal portion 42, the inner ring 41, and the inner ring 41 that are in contact with the container mouth. It consists of a thin-walled portion 43.

In the present invention, when the metal cap 1 having the above-described basic configuration is manufactured, after the metal panel 3 is inserted into a predetermined position in the cap shell 2, the curved outer peripheral edge 32 of the metal panel 3 is formed. It is an important feature that the metal panel 3 is expanded to increase the outer diameter.
FIG. 2 is a view for explaining the manufacturing method of the present invention, in which the top plate portion 20 is placed on the forming table 60 and the opening edge of the skirt portion 21 is installed in the upward direction. The metal panel 3 is inserted into the metal cap shell 2 having the above. As apparent from FIG. 2A, the outer diameter of the metal panel 3 inserted into the metal cap shell 2 is equal to or slightly larger than the inner diameter of the support portion 28 that supports the metal panel 3. The metal panel 3 is inserted into a predetermined position in the metal cap shell 2 without plastic deformation.

Next, a molten resin (not shown) supplied onto the metal panel 3 is embossed with the forming tool 6 to integrally form a liner on the metal panel 3. The forming tool 6 includes a center punch 61, a center pushing 62, and a locating sleeve 63. First, an outer peripheral edge 44 of the liner is defined by the locating sleeve 63 so that the molten resin does not protrude outside. The liner 61 having the inner ring 41, the seal portion 42, and the thin portion 43 is formed by the 61 and the center pushing 62.
As is clear from FIG. 2B, the forming tool 6 descends to form the liner 4, and at the same time, the locating sleeve 63 presses the outer peripheral edge 32 of the metal panel 3 from above, so that the curved portion is obtained. Will be expanded. That is, the outer peripheral edge portion 32 is in a state before being expanded as indicated by a two-dot chain line in FIG. 2B and a state after being expanded as indicated by a solid line. Thereby, the metal panel 3 (inner plug 5) on which the liner 4 is formed is securely held between the top plate portion 20 and the support portion 28 of the metal cap shell 2.

  Further, in the manufacturing method of the present invention, as is apparent from FIG. 3, the shape of the front end surface of the pressing sleeve that presses the outer peripheral edge of the metal panel is expanded and the front end surface of the metal panel is expanded. Since it is formed in the same shape as the metal panel shape of the part which contacts, the shape after the metal panel is expanded can be formed stably.

  FIG. 4A is a diagram showing a state in which the metal cap 1 shown in FIG. 1 is applied to the metal container 7. After the metal cap 1 shown in FIG. 1 is put on the mouth portion of the metal container 7, the corner portion of the boundary region between the top plate portion 20 and the skirt portion 21 is placed on the outer peripheral surface of the curl portion of the container with a tool (not shown). By pressing, the seal part 42 of the liner 4 is brought into close contact with the curl part 71 of the container mouth part, and the screw part engaged with the screw part 72 of the container mouth part in the thread forming region of the skirt part 21 by another tool (not shown). 29 is formed and the tamper evident band 23 is shaped to engage the bead 73 at the container mouth. In this state, the metal container 7 is securely sealed by the inner ring 41 and the seal portion 42 of the liner 4. In this state, the outer peripheral edge 33 and the support portion 28 are separated from each other.

  Next, as shown in FIG. 4B, by rotating the metal cap 1 in the opening direction, the metal cap shell 2 excluding the tamper evidence band 23 rises, and the cap shell 2 and the tamper evidence are removed. The weakened portion 22 connecting the band 23 is broken. However, since the separate inner stopper closely attached to the container mouth portion does not need to rotate, the rotational torque required for opening can be reduced. At this time, the metal container 7 has the inner ring 41 and The seal portion 42 is securely sealed. Thereafter, the support portion 28 of the metal cap shell 2 is engaged with the outer edge 33 of the metal panel 3.

As shown in FIG. 4 (C), when the metal cap 1 continues to turn, the outer peripheral edge 33 of the metal panel 3 is securely locked to the support portion 28 of the metal cap shell 2. The metal cap shell 2 is lifted without leaving the predetermined position, and the metal cap 1 is removed from the container mouth portion, leaving only the tamper evidence band at the container mouth portion.
Therefore, in the metal cap obtained by the present invention, before the weakened part connecting the lower end of the main part of the skirt part 21 and the tamper evidence band is broken and shown once opened, the sealing performance of the container is shown. Will not be released.

In the manufacturing method of this invention, it is not limited to the specific example mentioned above, A various change is possible.
For example, in the manufacturing method shown in FIG. 2, the outer peripheral edge of the metal panel is pushed and expanded simultaneously with the molding of the liner. However, the molding of the liner is not limited to this timing, and the metal panel is first placed in the cap shell. After inserting the outer peripheral edge of the metal panel and expanding the outer peripheral edge of the metal panel, it is possible to supply the molten resin to form the liner and integrate it with the metal panel. Of course, after the stopper is formed, the inner stopper is inserted into the cap shell and the outer peripheral edge of the metal panel can be expanded.

In the example shown in FIGS. 1 to 4, the inner cap is combined with the metal cap shell. However, the combination of the resin cap shell and the inner plug can be similarly manufactured.
That is, as shown in FIG. 5, the resin cap shell 8 comprises a top plate portion 82 having an opening 81 formed in the center portion and a skirt portion 84 having a screw portion 83 on the inner surface. The skirt portion 84 is composed of an upper main portion and a main portion. A tamper evidence band 86 formed integrally with the weakened portion 85 is provided at the lower end of the portion. The bottom surface of the side end portion of the opening 81 of the top plate portion 82 is inclined downward inward in the radial direction, and has a shape that matches the concave portion of the metal panel 3, and has a cap with an inner cap of a metal cap shell. As in the case of, the inner plug can be positioned with respect to the cap shell. The cap with the inner cap of the resin cap shell is configured by inserting the inner cap 5 in which the annular liner 4 is integrally formed on the metal panel 3 into the resin cap shell 8.
A curled portion 35 is formed at the outer peripheral end of the metal panel 3. As shown in FIG. 5, the inner plug can be efficiently installed in the same manner as in FIGS. 1 to 4 by expanding the inner side from the center of the curl of the curled portion 35 with the annular sleeve 64. .

In this aspect, when the resin cap mounted on the container is turned in the opening direction, the cap starts to rise along the screw, while the locking means inside the tamper-evidence band is not shown in the container mouth portion (not shown). Since the tamper evidence band is locked by being locked to the locked means, the weakened portion 85 that connects the skirt main portion and the tamper evidence band is broken. Subsequently, when the cap shell 8 continues to rise, the curled portion of the inner plug 5 engages with the uppermost end surface of the screw portion 83, so that the inner plug 5 rises together with the cap shell 8 and is detached from the cap shell 8. Without removing from the container mouth.
In this embodiment, an opening 81 is formed in the top plate portion 82 of the cap shell 8 and the inner plug 5 covers the opening. Needless to say, the top plate portion may have no opening. . Further, it is of course possible to separately form a support portion made of an annular protrusion or the like for locking with the inner plug above the screw portion and holding the inner plug in the cap shell.

  In the metal cap shell shown in FIG. 1, by utilizing the opening 25 for introducing the washing water, the lower region 27 of the opening 25 is projected inward in the radial direction, whereby the inner plug 5 is connected to the cap shell 2. As in the case of the resin cap shell described above, the upper end surface of the screw may be used in the metal cap shell, or an annular shape protruding radially inward above the screw portion. A support part for holding the inner plug in the cap shell, such as forming a protrusion, may be formed separately.

The outer edge of the metal panel 3 does not need to be curled particularly when the metal panel is made of an aluminum plate. However, when the metal panel is made of a steel plate such as tin-free steel or tinplate, rusting occurs. From the viewpoint of prevention, it is desirable that curling is performed for edge protection.
In addition, the concave portion formed in the central portion of the metal panel is effective for positioning to the metal cap shell as shown in FIG. 1, but it is not always necessary to form it if positioning by other means is possible. .
Furthermore, the liner is not limited to molding by pressing a molten resin on a metal panel, and can be molded by a conventionally known method such as spin lining.

According to the method of manufacturing a cap having an inner plug of the present invention, when the inner plug is installed in the cap shell, the metal panel can be easily inserted into the cap shell without causing deformation of the inner plug, and the cap shell is detached. It is possible to use an inner plug having an outer diameter without any problem, and it can be suitably used for manufacturing a cap with an inner plug used in a container in which the inside of the container is depressurized by hot filling or the like.
Further, since the outer diameter of the metal panel can be increased simultaneously with the molding of the liner material, the number of processes is small, and the productivity and economy are excellent. Therefore, it can be suitably used for general-purpose caps that require mass production.
Furthermore, since the cap manufactured by the method of the present invention has a metal panel on the top plate portion, the torque required for opening is small, the gas barrier property is excellent, and the container is filled with contents and the like that are greatly affected by oxygen It can use suitably for manufacture of the cap used for.

  DESCRIPTION OF SYMBOLS 1 Metal cap, 2 Metal cap shell, 3 Metal panel, 4 Liner, 5 Inside plug, 6 Molding tool, 7 Metal container, 8 Resin cap shell, 28 Support part (opening edge), 32 Outer periphery Part, 33 outer edge

Claims (5)

With an inner plug comprising a cap shell comprising a top plate portion and a skirt portion, and having a thread forming region formed on the skirt portion, and an inner plug having a metal panel and a resin liner on the inner surface side of the metal panel. In the method of manufacturing a cap,
After inserting the metal panel into the cap shell, the inner plug can be removed from the cap shell by a support part formed inside the upper part of the skirt part by expanding the outer peripheral edge of the metal panel. And the manufacturing method of the cap with an inside plug characterized by hold | maintaining so that an up-down movement is possible in the predetermined position above a support part.   The manufacturing method according to claim 1, wherein when the molten resin is compressed on the inner surface side of the metal panel of the inner plug and the resin liner and the metal panel are integrally formed, the outer peripheral edge of the metal panel is expanded. With an inner plug comprising a cap shell comprising a top plate portion and a skirt portion, and having a thread forming region formed on the skirt portion, and an inner plug having a metal panel and a resin liner on the inner surface side of the metal panel. In the method of manufacturing a cap,
By simultaneously expanding the outer peripheral edge of the metal panel while inserting the metal panel into the cap shell, the inner plug cannot be detached from the cap shell by the support part formed inside the upper part of the skirt part. And the manufacturing method of the cap with an inside plug characterized by hold | maintaining so that an up-down movement is possible in the predetermined position above a support part.   The cap shell is made of metal, and a plurality of openings are formed in the upper end portion of the skirt portion at intervals in the circumferential direction. A lower region along a cutting line engraved in the skirt portion is formed in the opening. The manufacturing method according to claim 1, wherein the support portion is formed by protruding inward in the radial direction.   The shape of the tip surface of the pressing sleeve that presses the outer peripheral edge of the metal panel is formed to be the same shape as the shape of the metal panel at the portion where the metal panel after being expanded and the tip surface abuts. The manufacturing method of the cap with an inside stopper in any one of Claim 1 thru | or 4.

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