JP2008239185A - Resin-made container lid having tamper-evident property and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a container lid which is sufficiently and firmly fixed to a container mouth while the tamper-evident property is not impaired. <P>SOLUTION: The resin-made container lid having the tamper-evident property comprises a top wall 12 and a cylindrical skirt wall 18 hanging from a circumferential edge of the top wall. A circumferential weakening line 13 extending in the circumferential direction is formed below the skirt wall. The skirt wall is divided into an upper main part 14 the circumferential weakening line and a lower tamper-evident band 16. A female thread line 17 threadedly engaged with a male thread line 76 of a container mouth 70 is provided on an inner circumferential surface of the main part of the skirt wall. A locking means 19 to be locked to a locking projecting part 74 provided below the male thread line of the container mouth is provided on an inner circumferential surface of the tamper-evident band. The locking means cuts a part of the tamper-evident band discontinuously in the circumferential direction, has the tamper evident property formed by deforming an area below the cut position inwardly. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin container lid having tamper evidence characteristics and a method of manufacturing the resin container lid.

  As a container lid applied to a container such as a beverage that can be formed from a synthetic resin, glass, or the like, a resin container lid having tamper evidence characteristics is practically used. As such a resin container lid, Patent Document 1 includes a screw lid screwed into a bottle mouth (container mouth portion) and a ring body (tamper evidence band) located below the ring lid. Describes a pilfer-proof cap connected to the lower end of the screw lid via a plurality of bridge portions along the circumferential direction.

Such a container lid is applied to a container in which a male thread and a container projection located below the male thread are formed on the outer peripheral surface of the container mouth, and the container lid is fitted on the container mouth. Then, the container is rotated in the closing direction, and the female thread of the container lid is screwed into the male thread of the container mouth to seal the container mouth of the container.
The container lid descends with respect to the container mouth as it rotates in the closing direction, and the locking means (protrusions) formed on the tamper-evidence band of the container lid push the locking projections (flange) on the container mouth. Get over it elastically and lock it.
On the contrary, when the container lid is rotated in the opening direction, the screwing of the female thread of the container lid to the male thread of the container mouth portion is released, and the container lid can be opened by raising.
At this time, the tamper-evident band is prevented from rising because the locking means is locked to the locking projection of the container mouth, and as a result, considerable stress is applied to the circumferential weakening line (bridge portion). As a result, the circumferential weakening line is broken, and the container lid can be detached from the container mouth, leaving the tamper evidence band at the container mouth.
JP-A-5-276368

However, the container lid of Patent Document 1 ensures resistance at the time of mold release and tamper evidence when being mounted on the container mouth when molding a tamper-evidence band with a protrusion from the container lid preform. In order to obtain an appropriate rigidity, it was necessary to devise such as thickening the tamper evidence band.
On the other hand, if the tamper evident band is made thin and an undercut is provided on it, it is necessary to taper the upper surface of the undercut to remove the mold, so that the tamper evidence band is opened when the container lid is opened. There was a possibility that troubles such as slipping off would occur.

The present invention has been made in view of the above-mentioned facts, and the main problem is that in addition to being able to be sufficiently firmly fixed to the container mouth with a tamper evidence band, the container mouth of the container is mounted with a container lid. It is an object of the present invention to provide a resin container lid having a tamper evidence characteristic without impairing the appearance of the container lid and without deteriorating the tamper evidence characteristic, and a method for producing the same.
Another object of the present invention is to provide a resin container lid having a light tamper evidence characteristic in which the tamper evidence band is thinned to reduce the amount of resin used in the container lid, and a method for producing the same. .
Furthermore, another object of the present invention is to provide a resin container lid having a tamper evidence characteristic that does not cause problems such as slipping off of the tamper evidence band when the container lid is opened, and a method for manufacturing the same. That is.

The resin container lid provided with the tamper evident characteristics of the present invention is capable of fixing the container lid sufficiently firmly to the container mouth with a tamper evidence band, and the appearance of the container lid with the container lid attached to the container mouth is It is not impaired and also the tamper evidence properties are not impaired.
In addition, it is a lightweight container lid that reduces the amount of resin used for the container lid by reducing the thickness of the tamper evidence band, and does not cause problems such as slipping off of the tamper evidence band when the container lid is opened. .

(1) A resin container lid having tamper evident characteristics of the present invention has a top wall and a cylindrical skirt wall depending from the periphery of the top wall, and a circumferential direction extending in the circumferential direction below the skirt wall A weakening line is provided, and the skirt wall is divided into a main part above the circumferential weakening line and a tamper evidence band below, and is formed on the inner peripheral surface of the main part of the skirt wall. Is provided with a female thread to be engaged with the male thread at the container mouth, and a locking projection provided below the male thread at the container mouth on the inner peripheral surface of the tamper evint band. A resin container lid having tamper evidence characteristics provided with a locking means for locking to a portion, wherein the locking means discontinuously cuts a part of the tamper evidence band in the circumferential direction. In addition, deform the area below the cut position inward Characterized in that it is one that is formed by.
(2) The resin container lid having the tamper-evident characteristic according to the present invention is the resin container lid according to (1), wherein the locking means has an open upper end, and left and right side portions and a bottom portion are connected to a tamper-evident band. It consists of a stop part, The horizontal cross section of this latching | locking part is substantially circular arc shape, and it protrudes and forms in the radial direction, It is characterized by the above-mentioned.
(3) The method for producing a resin container lid having tamper evidence characteristics according to the present invention is a method of molding the resin container lid having tamper evidence characteristics of (1), wherein the locking means is a container. After forming the molded body before the lid, the tamper evidence band is formed by a deformation process in which the tamper evidence band is discontinuously cut and a region below the cut position is deformed inward. The heated punch having a cutting blade that is in contact with the outside is moved relatively inward of the molded body of the container lid, and cutting and deformation are continuously performed.

Hereinafter, an embodiment of a resin container lid having tamper evidence characteristics constructed according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a left half sectional view of a container lid according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 3 is a cross-sectional view showing a state in which the container lid is attached to the container mouth, and the left side shows a cross section and the right side is an external view. FIG. 4 is an enlarged cross-sectional view showing a state in which a portion of the locking means in FIG. 3 is enlarged.
As shown in FIGS. 1 to 4, the container lid 10 includes a disk-shaped top surface wall 12 and a substantially cylindrical skirt wall 18 that hangs down from the periphery of the top surface wall 12. An annular inner ring 22 that extends in the circumferential direction and an outer ring 24 that hangs downward in the radial direction are formed on the lower surface on the inner surface side of the top wall 12. ing.

  In addition, a circumferential weakening line 13 is formed at the lower part of the skirt wall 18, and the skirt wall 18 is partitioned into a main portion 14 above the circumferential weakening line 13 and a lower tamper evidence band 16. ing. The main portion 14 of the skirt wall 18 has a female thread 17 formed on the inner peripheral surface thereof, and a knurled eye 26 for preventing finger slipping at the time of opening the cap is formed on the outer peripheral surface. .

  The tamper evident band 16 is formed of a thin wall extending continuously in the circumferential direction, the outer diameter of which is smaller than the outer diameter of the skirt wall 18. A plurality of locking means 19 for locking to locking protrusions 74 provided below the male thread 76 of the 70 are formed at intervals in the circumferential direction.

The locking means 19 has a part of the tamper-evident band 16 in the circumferential direction so that the locking means 19 is locked to a locking protrusion 74 that protrudes outward in the circumferential direction below the container mouth portion 70. In addition to being cut discontinuously, the region below the cut position is deformed inward in the radial direction.
Such a locking means 19 has a locking portion in which the upper end 19a is opened and the left side portion 19b, the right side portion 19c and the bottom portion 19d are connected to the tamper evident band 16, and the horizontal cross section of the locking portion is substantially circular. It has an arc shape and is formed to protrude radially inward.
Further, such a locking means 19 is formed by, for example, cutting the tamper-evident band 16 discontinuously after forming the container lid pre-formed body 10a, and inward the area below the position cut in the cutting process. It is formed by deforming. This deformation operation can be formed by bringing the heated punch 50 with a cutting blade into contact with the outside of the tamper-evidence band 16 and moving it radially inward to continuously perform the cutting step and the deformation step. In addition, the punch 50 with a cutting blade can also be made to deform | transform at the predetermined temperature which controlled the tamper evident band 16 by incorporating punch heating means 52, such as a heater.

Examples of the container to which the container lid 10 is applied include a general container that can be molded from glass or an appropriate synthetic resin. As such a container, the container mouth portion 70 has a substantially cylindrical shape. The outer peripheral surface is formed with two-stage male threads 76 spaced apart in the axial direction and a locking projection 74 for locking the locking means 19.
In addition, as a raw material which comprises the container cover 10, suitable synthetic resins, such as a polypropylene or polyethylene, are mentioned.

FIG. 4 is an enlarged cross-sectional view of the locking means 19. As shown in FIG. 4, the locking means 19 formed on the inner peripheral surface of the tamper evident band 16 has a part of the tamper evidence band 16 cut off, the upper end 19a opened, and below the cut position. The upper end 19 a is opened and is in contact with the lower side of the locking projection 74.
The inclination angle θ1 is an angle formed by the outer surface of the locking means 19 with the axial direction of the container lid 10, and the inclination angle θ1 is preferably formed at a small angle (preferably 30 to 40 degrees). . By setting the inclination angle θ1 to such an angle, when the container lid 10 is attached to the container mouth portion 70, it is easy to get over the locking projection 74, and once it gets over the locking projection 74, it is fitted. It is possible to make it difficult for the container lid 10 thus removed to come out of the container mouth portion 70.

Next, the manufacturing method of the latching means provided in the container lid according to the embodiment of the present invention will be described in detail with reference to FIGS.
FIG. 5 is a left half sectional view of the container lid pre-formed body showing a state before the locking means is formed on the container lid of FIG. 1. FIG. 6 is a partial cross-sectional view of the container lid preform, showing a state in which a punch with a cutting blade is brought into contact with the outside of the tamper evidence band in order to form a locking means on the container lid preform. FIG. 7 shows a state in which a punch with a cutting blade is brought into contact with the outside of the tamper evidence band, a part of the tamper evidence band is discontinuously cut and pushed inward and deformed to form a locking means. It is a partial cross section figure of a molded object. FIG. 8 is a partial cross-sectional view of the container lid pre-formed body showing a state before the circumferential weakening line is formed on the container lid of FIG. 1. FIG. 9 is a partial cross-sectional view of the container lid pre-formed body showing a state where a cutting blade is applied from the outer peripheral surface of the skirt wall to form a circumferential weakening line. FIG. 10 is a partial cross-sectional view of the container lid showing a state in which locking means and a circumferential weakening line are formed in the tamper evident band.

The container lid pre-molded body 10a taken out from the mold after the resin molding has a thin tamper evidence band 16 below as shown in FIG. 5, and a part of the tamper evidence band 16 is contained inside. The locking means 19 is formed by deforming in the direction.
That is, as shown in FIG. 6, a die 55 provided with a gap 56 at a position corresponding to the locking means 19 formed in the tamper evidence band 16 is fitted inside the container lid preform 10a, The lower end of the tamper evidence band 16 is pressed by the skirt pressing member 58, and the punch 50 with the cutting blade provided with the heated cutting blade 51 is brought into contact with the outside of the tamper evidence band 16.
Then, as shown in FIG. 7, the punch 50 with a cutting blade is pushed from the outside of the tamper evidence band 16 into a part of the tamper evidence band 16 inward in the radial direction, and the tamper evidence band 16 is discontinuously cut. Further, the punch 50 with a cutting blade is relatively moved inward of the container lid preform 10a, and the area below the cut position is deformed inward to form the locking means 19. At this time, the die 55 fitted with the container lid preform 10a is rotated about the shaft 57, and the punch 50 with a cutting blade is moved back and forth in the radial direction, so that the tamper evidence band 16 is moved in the circumferential direction. The locking means 19 can be formed discontinuously.
Other methods for forming the locking means 19 include the following method.
For example, while the die 55 fitted with the container lid preform 10a is pushed into the tip of the arc-shaped cutting blade punch 50, the die 55 is rotated (spinned) and along the arc-shaped cutting blade punch 50. Rotating (revolving) to cut and deform, and conversely, the die 55 fitted with the container lid preform 10a is kept stationary, and the rotary punch with cutting blade is tamper-evident band. There are methods of pushing, cutting and deforming while rotating along the outer periphery of 16.

Next, a circumferential weakening line is provided in the circumferential direction below the skirt wall 18 of the container lid preform 10a. That is, as shown in FIG. 8, a circumferential direction weakening line is formed above the tamper evident band 16 in which the locking means 19 is formed.
As shown in FIG. 9, the circumferential weakening line 13 is formed by pushing the cutting blade 53 from the outer peripheral surface of the skirt wall 18 radially inward below the skirt wall 18 to cut into a part of the tamper evidence band 16. To put.
At this time, the circumferential weakening line 13 can be formed on the entire circumference below the skirt wall 18 by rotating the die 55 fitted with the container lid preform 10a about the shaft 57.
In addition, the circumferential direction weakening line 13 which cut | disconnected the perforation shape can also be formed by moving the cutting blade 53 back and forth in radial direction.
In addition, as a method of forming the circumferential weakening line 13, there is the following method.
For example, while the die 55 fitted with the container lid preform 10a is brought into contact with the tip of the arc-shaped cutting blade 53, the die 55 is rotated (rotated) and rotated along the arc-shaped cutting blade 53 (revolution). ). In this case, a perforated cut can be efficiently formed by making the portion where the blade is formed convex and making the portion not formed concave.

  FIG. 10 is a partial cross-sectional view of the container lid showing a state in which the locking means and the circumferential weakening line 13 are formed on the container lid. That is, a plurality of locking means 19 in FIG. 10 are formed discontinuously in the circumferential direction of the container lid 10. A plurality of such discontinuously formed locking means 19 are locked to locking protrusions 74 provided below the male thread 76 of the container mouth portion 70, so that the container mouth portion 70 can be sealed by the container lid 10 (see FIG. 3).

Next, mounting (capping) and removing (opening) of the container lid of the container lid from the container mouth will be described.
First, when the container lid 10 is attached to the container mouth portion 70 of the container filled with the contents, the container lid 10 is fitted on the container mouth portion 70 of the container, and the container lid 10 is rotated in the closed rotation direction, that is, In FIG. 1, it is rotated clockwise as viewed from above. In this way, the male thread 76 of the container mouth part 70 is screwed with the female thread 17 provided on the inner peripheral surface of the skirt wall 18, and the container lid 10 follows the container mouth part 70 according to the rotation. And descend.
Then, the locking means 19 formed on the inner peripheral surface of the tamper evident band 16 in the skirt wall 18 of the container lid 10 makes the locking projection 74 formed on the outer peripheral surface of the container mouth portion 70 elastic. And is locked below the locking projection 74.
At this time, since the inclination angle θ1 of the locking means 19 is formed to be loose, the locking projection 74 can be easily overcome.

On the other hand, the cutting surface on the opposite side to the inclination angle θ1 of the locking means 19 is formed to protrude inward in the radial direction and is positioned below the locking projection 74 provided at the container mouth portion. The container lid 10 once fitted over the locking protrusion 74 is difficult to be removed from the container opening 70.
In the container lid 10 of the present invention, since the thin tamper-evidence band 16 extends continuously in the circumferential direction, the tamper-evidence band is attached when the container lid 10 is attached to the container mouth portion 70 of the container. 16 can be easily deformed and can easily get over the locking projection 74. Therefore, when the container lid 10 is attached to the container mouth, the appearance of the container lid 10 is not impaired and the tamper evidence characteristics are not impaired.

On the other hand, in order to remove the container lid 10 from the container mouth portion 70 of the container, the container lid 10 is rotated in the opening rotation direction, that is, counterclockwise as viewed from above in FIG. The screwing of the container mouth portion 70 with the male thread 76 is gradually released.
In this way, the skirt wall 18 of the container lid 10 is not raised, but the tamper-evidence band 16 of the skirt wall 18 has a locking means 19 formed on the inner peripheral surface thereof so that the container mouth portion 70 is engaged. Since it is engaged below the stop protrusion 74, the ascent is prevented, so that a considerable stress is generated in the circumferential weakening line 13 formed in the skirt wall 18 and the circumferential weakening line 13 is broken. .
As a result, the tamper evident band 16 is completely separated from the main portion 14 of the skirt wall 18, and the tamper evidence band 16 remains in the container mouth portion 70 without being detached from the container mouth portion 70.
On the other hand, the main portion 14 of the container lid 10 from which the tamper evidence band 16 has been separated is raised along the container mouth portion 70 and detached from the container mouth portion 70. As a result, the container mouth portion 70 is exposed.

The resin container lid having tamper evident characteristics of the present invention can be fixed firmly to the container mouth with a tamper evidence band, and in addition, the appearance of the container lid with the container lid attached to the container mouth of the container Has a tamper-evidence characteristic that is not damaged, and that the tamper-evidence characteristic is not damaged.
It is a lightweight container lid with a thin tamper-evidence band that reduces the amount of resin used in the container lid, and there are no problems such as slipping off the tamper-evidence band when opening the container lid. High availability on.

It is a left half sectional view of the container lid of one embodiment of the present invention. It is AA sectional drawing of FIG. It is sectional drawing which shows the state which mounted | wore the container opening | mouth part with the container lid, the left side shows a cross section, and the right side is an external view. It is an expanded sectional view which shows the state which expanded the part of the latching means of FIG. FIG. 2 is a left half sectional view of a container lid pre-formed body showing a state before the locking means is formed on the container lid of FIG. 1. It is a partial cross section figure of a container lid which shows the state which a punch with a cutting blade is made to contact | abut on the outer side of a tamper evidence band in order to form a latching means in a container lid preform. One of the container lid preforms showing a state in which a punch with a cutting blade is brought into contact with the outside of the tamper evidence band and a part of the tamper evidence band is cut discontinuously and pushed inward to form a locking means. FIG. FIG. 2 is a partial cross-sectional view of a container lid pre-formed body showing a state before a circumferential weakening line is formed on the container lid of FIG. It is a partial cross-sectional view of the container lid pre-formed body showing a state in which a cutting blade is applied from the outer peripheral surface of the skirt wall to form a circumferential weakening line. It is a partial cross section figure of the container lid which shows the state which formed the latching means and the circumferential direction weakening line in the tamper evident band.

Explanation of symbols

10: Container lid 10a: Container lid preform 12: Top wall 14: Main portion 16: Tamper evidence band 17: Female thread 18: Skirt wall 19: Locking means 13: Circumferential weakening line 22: Inner ring 24 : Outer ring 26: Knurled eye 50: Punch with cutting blade 52: Punch heating means 53: Cutting blade 55: Die 56: Recess 57: Shaft 58: Bottom holding member 70: Container mouth 74: Locking protrusion 76: Male Thread

Claims (3)

A top wall and a cylindrical skirt wall depending from the periphery of the top wall;
A circumferential weakening line extending in the circumferential direction is provided below the skirt wall,
The skirt wall is partitioned into a main part above the circumferential weakening line and a tamper evidence band below.
An internal thread of the main part of the skirt wall is provided with a female thread that engages with a male thread of the container mouth part, and a male thread of the container mouth part is disposed on the inner peripheral surface of the tamper evident band. A resin container lid having tamper evidence characteristics provided with a locking means for locking to a locking projection provided below the thread,
The locking means is formed by cutting a part of the tamper evidence band discontinuously in the circumferential direction and deforming a region below the cut position inward. A resin container lid having tamper evidence characteristics. The locking means includes a locking portion having an open upper end, a left side portion, a right side portion, and a bottom portion connected to a tamper evidence band, and the horizontal cross section of the locking portion has a substantially arc shape, The resin container lid having tamper-evidence characteristics according to claim 1, wherein the resin container lid has a tamper-evidence characteristic. A method for molding a resin container lid having tamper evidence characteristics according to claim 1,
The locking means is formed by a cutting deformation process in which after the container lid preform is molded, the tamper evidence band is discontinuously cut, and a region below the cut position is deformed inward. Yes, the heated punch with a cutting blade in contact with the outside of the tamper-evidence band is moved relatively inward of the container lid preform to continuously perform cutting and deformation. A method for producing a resin container lid.

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