JP2015093704A - Synthetic resin container lid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic resin container lid that reliably prevents a mouth/neck part (44) of a container from being fraudulently opened and that prevents an accidental breakage in a breaking line (18) to the utmost when the container lid (2) is attached to the mouth/neck part.SOLUTION: Each form of a locking protrusion (34) assumes a peculiar form in which a radial extension length (La) of a locking top surface (38) of a circumferential intermediate part (34a) is greater than a radial extension length (Lb) of locking top surfaces (38) of both circumferential side parts (34b).

Description

  The present invention relates to a synthetic resin container lid having tamper-evident characteristics, more specifically, a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall. The skirt wall is partitioned into a main part above the breaking line and a tamper evidence hem below the breaking line, and a female screw is formed on the inner peripheral surface of the main part of the skirt wall. A plurality of locking projections extending in the circumferential direction are arranged on the inner peripheral surface of the tamper evidence skirt at intervals in the circumferential direction, and each of the locking projections is radially inward. The present invention relates to a synthetic resin container lid having a locking upper surface extending to the surface.

  As is well known, a synthetic resin container lid for a beverage container having a cylindrical mouth and neck portion having a male thread and a locking jaw located below the male thread on the outer peripheral surface. For example, as disclosed in Patent Document 1 below, a circular top surface wall and a cylindrical skirt wall hanging from the periphery of the top surface wall are provided, and a rupture line extending in the circumferential direction is formed on the skirt wall. A synthetic resin container lid, in which the skirt wall is divided into a main portion above the breaking line and a tamper evidence skirt below the breaking line, is widely used. Female threads are formed on the inner peripheral surface of the main part of the skirt wall. A plurality of locking projections extending in the circumferential direction are arranged on the inner peripheral surface of the tamper evidence skirt at intervals in the circumferential direction, and each of the locking projections extends radially inward. It has a stop surface.

  The synthetic resin container lid as described above is fitted on the mouth and neck of the container and rotated in the closed rotation direction, that is, clockwise when viewed from above, and the female screw of the container lid is threaded on the male thread of the mouth and neck. It is attached to the mouth and neck by screwing the strips together. The locking protrusion formed on the inner peripheral surface of the tamper evidence skirt is elastically over the locking jaw of the mouth and neck and is positioned below the locking protrusion. When opening the mouth / neck portion of the container to consume the contents of the container, the container lid is rotated in the opening rotation direction, that is, counterclockwise as viewed from above. In this way, the threaded engagement of the female thread with the male thread is gradually released, and the main part of the top wall and the skirt wall of the container lid does not rise with the rotation in the opening direction. The upper surface of the locking projection formed on the peripheral surface is locked to the locking jaw portion of the mouth-neck portion to prevent the rise, thus generating stress in the breaking line and breaking the breaking line. The evidence hem is separated from the main part of the skirt wall. After that, the tamper-evidence hem is left in the mouth and neck, and the main part of the top wall and skirt wall is freely raised along with the rotation in the opening rotation direction and detached from the mouth and neck. Is opened. In the case of a synthetic resin container lid in which a rupture line extending in the axial direction is formed at the skirt of the tamper evidence, the rupture of the rupture line extending in the circumferential direction is broken not in the circumferential direction but in part. The axially extending break line formed in the tamper evidence hem is broken and the tamper evidence hem is changed from an endless annular shape to an end band shape, thereby The locking projection of the locking jaw is released from the locking jaw of the part, and then the entire container lid including the tamper evidence hem is freely raised along with the rotation in the opening rotation direction and detached from the mouth and neck, The mouth and neck are opened.

JP 2011-143942 A

  According to the experience of the present inventor, the conventional synthetic resin container lid of the form as described above has (1) a finger or an appropriate tool engaged with the end of the tamper evidence hem, and outward in the radial direction. By rotating the container lid in the opening rotation direction while displacing it, there is no possibility that the entire mouth of the container lid will be detached from the mouth and neck without breaking the breaking line and the mouth and neck may be illegally opened. (2) When the container lid is attached to the mouth / neck portion of the container, the locking protrusion disposed on the inner peripheral surface of the tamper-evidence hem portion elastically overcomes the locking jaw portion of the mouth / neck portion. At this time, there is a problem to be solved that the break line may be accidentally broken.

  The present invention has been made in view of the above-mentioned facts, and the main technical problem thereof is to reliably prevent the mouth and neck from being tampered with as described above. It is intended to provide a new and improved synthetic resin container lid in which it is possible to prevent as much as possible the accidental breakage of the break line when mounting the container.

  As a result of intensive studies, the present inventor has ensured that the neck and neck portion are illegally opened as described above when the radially extending length of the locking upper surface of each locking projection is relatively long. In view of the fact that when the container lid is attached to the mouth and neck, the tendency of the break line to be accidentally broken increases, the shape of each of the locking projections is related to the middle of the circumferential direction. It has been found that the above-mentioned main technical problem can be achieved by making the extending length of the stop surface in the radial direction have a unique shape larger than the extending length of the locking upper surface in the circumferential direction on both sides.

That is, according to the present invention, the synthetic resin container lid for achieving the main technical problem includes a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall, and the skirt wall has a circumferential direction. The skirt wall is partitioned into a main portion above the break line and a tamper evidence skirt below the break line, and the main portion of the skirt wall. A female thread is formed on the inner peripheral surface of the tamper-evident skirt, and a plurality of locking projections extending in the circumferential direction are arranged on the inner peripheral surface of the tamper evidence skirt at intervals in the circumferential direction. Each of the locking projections is a synthetic resin container lid having a locking upper surface extending radially inward,
A radial extension length of the locking upper surface of the circumferential intermediate portion in each of the locking projections is set to be greater than a radial extension length of the locking upper surface on both sides in the circumferential direction. A synthetic resin container lid is provided.

  Preferably, the locking projections are arranged in an odd number, particularly five, at equal intervals in the circumferential direction, and the circumferential lengths of the locking projections are the same. A locking projection non-existing portion where the locking projection does not exist is located at a portion of each circumferential intermediate portion opposite to the diameter direction. It is advantageous that the extension length of the circumferential intermediate portion of each of the locking projections inward in the radial direction is gradually reduced from the circumferential middle toward both sides in the circumferential direction. Each of the locking projections has a guide lower surface extending obliquely outward in a radial direction downward, and a lower edge of the guide lower surface extends from a circumferential middle portion to at least a part of both circumferential side portions. It is preferred to extend horizontally across.

  In the synthetic resin container lid of the present invention, the radially extending length of the locking upper surface of the circumferential intermediate portion in each locking projection is larger than the radially extending length of the locking upper surface on both circumferential sides. Therefore, it is effectively prevented that the finger or an appropriate tool is locked at the end of the tamper evidence skirt and displaced radially outward to damage the locking. On the other hand, since the extending length in the radial direction of the locking upper surface is set to be large only in the circumferential intermediate portion of each locking protrusion, particularly when the container lid is attached to the mouth and neck of the container, the tamper evidence It is avoided as much as possible that the breaking line is accidentally broken when the locking projections arranged on the inner peripheral surface of the hem elastically cross the locking jaw of the mouth and neck. The

The front view which shows a suitable embodiment of the synthetic resin container lid comprised according to this invention in part in a cross section. The bottom view of the container lid of FIG. The fragmentary sectional view which shows the latching protrusion in the container lid shown in FIG.

  Hereinafter, a preferred embodiment of a synthetic resin container lid constructed according to the present invention will be described in more detail with reference to the accompanying drawings.

  Referring to FIG. 1, a container lid 2 that can be injection-molded or compression-molded from a suitable synthetic resin such as polyethylene or polypropylene includes a circular top wall 4 and a cylindrical skirt depending from the periphery of the top wall 4. Wall 6. A relatively short cylindrical outer seal piece 10 that hangs downward is formed on the outer peripheral edge of the inner surface of the top wall 4 together with a relatively long cylindrical inner seal piece 8 that hangs downward. An annular protrusion 12 is formed at the outer peripheral surface proximal end portion of the inner seal piece 8.

  The skirt wall 6 has a relatively thick thick upper portion 14 and a relatively thin thin thin portion 16. A rupture line 18 extending in the circumferential direction is formed at the upper end of the thin lower portion 16, and the skirt wall 6 is divided into a main portion 20 above the rupture line 18 and a tamper evidence skirt 22 below the rupture line 18. Has been. In the illustrated embodiment, the breaking line 18 includes a plurality of circumferentially extending slits (cut grooves) 24 and a plurality of bridging portions 26 that remain between the slits 24. The dent skirt 22 is connected to the main portion 20 via a plurality of bridging portions 26.

  On the outer peripheral surface of the main portion 20 of the skirt wall 6, anti-skid knurls 28 are formed which are formed of uneven shapes alternately present in the circumferential direction. On the inner peripheral surface of the main portion 20 of the skirt wall 6, a plurality of notches 32 extending in the axial direction together with the female threads 30 are formed.

  A plurality of locking protrusions 34 are disposed on the inner peripheral surface of the tamper evidence skirt 22 at intervals in the circumferential direction. In a preferred embodiment, an odd number of locking projections 34 are arranged at equal intervals in the circumferential direction, and the circumferential lengths of the locking projections 34 are substantially the same. A locking protrusion non-existing portion 36 where no locking protrusion exists is located on the opposite side in the diameter direction of each circumferential intermediate portion 34a. In the illustrated embodiment, five locking projections 34 are arranged at equal intervals in the circumferential direction, and the circumferential lengths of the locking projections 34 are substantially the same. There is a locking protrusion non-existing portion 36 on the opposite side in the diameter direction of each circumferential intermediate portion 34 a of 34.

  2 and FIG. 3 together with FIG. 1, each of the locking projections 34 has a locking upper surface 38 extending radially inward, and a tip surface having a substantially semicircular arc shape in a longitudinal sectional view. 40 and a lower guide surface 42 that extends downwardly and radially outwardly. In the container lid 2 configured according to the present invention, the length of the locking upper surface 38 extending inward in the radial direction is not the same in the entire circumferential direction in each of the locking projections 34. It is important that the extension length La at the intermediate portion 34a is set to be larger than the extension length Lb at both sides in the circumferential direction. In the illustrated embodiment, the extension length La at the circumferential intermediate portion 34a of the locking upper surface 38 is gradually reduced from the middle in the circumferential direction to the extension length Lb toward both sides in the circumferential direction. The length Lb of the locking upper surface 38 extending inward in the radial direction at both circumferential side portions 34b is constant. The extended lengths La and Lb of the locking upper surface 38 are the hardness of the synthetic resin material forming the container lid 2, the circumferential length of the locking protrusion non-existing portion 36, and the thickness of the tamper evidence skirt 22. Now, it can be set as appropriate based on the shape of the locking jaw in the mouth and neck of the container to which the container lid 2 is applied. In the illustrated embodiment, the lower edge of each guide lower surface 42 of the locking projection 34 extends substantially horizontally from the circumferential intermediate portion 34a to a part of the side portions 34b (ie, the inner half). (See FIG. 1). In the outer half of the circumferential side portions 34b, the lower edge of the guide lower surface 42 is inclined upward in the axial direction toward the outer circumferential end.

  FIG. 1 also shows the mouth / neck portion 44 of the container together with the container lid 2. The mouth and neck portion 44 of a container which can be formed from an appropriate synthetic resin such as polyethylene terephthalate, glass or a metal thin plate has a cylindrical shape as a whole, and a male screw 46 and a male screw are formed on the outer peripheral surface of the mouth and neck portion 44. A locking jaw portion 48 located below 46 is formed. The locking jaw portion 48 has an arcuate upper surface whose outer diameter gradually increases downward and a lower surface extending substantially horizontally. Further provided on the outer peripheral surface of the mouth / neck portion 44 is a support ring 50 located below the locking jaw portion 48 (the support ring 50 is used for transporting containers as is well known to those skilled in the art). ing.

  When the container lid 2 is attached to the mouth and neck portion 44 after the contents are filled in the container and the mouth and neck portion 44 is sealed, the container lid 2 is fitted on the mouth and neck portion 44 and the container lid 2 is closed. 1, the female screw 30 of the container lid 2 is screwed to the male screw 46 of the mouth-and-neck portion 44. When the female thread 30 is screwed onto the male thread 46 until the state shown in FIG. 1, the inner seal piece 8 of the container lid 2 enters the mouth neck part 44 and is brought into close contact with the inner peripheral surface of the mouth neck part 44. The annular protrusion 12 is brought into close contact with the top surface of the mouth-and-neck portion 44, and the outer seal piece 10 is brought into intimate contact with or close to the outer peripheral surface of the mouth-and-neck portion 44, thus sealing the mouth-and-neck portion 44.

  When the description is continued with reference to FIG. 1, when the container lid 2 is attached to the mouth / neck portion 44 and the mouth / neck portion 44 is sealed, the tamper-evidence hem portion 22 is disposed on the inner peripheral surface. The locking projection 34 elastically climbs over the locking jaw 48 of the mouth / neck 44 and is positioned below the locking jaw 48. At this time, the locking projection 34 is gradually displaced outward in the radial direction by the guiding action of the guide lower surface 42 of the locking projection 34, so that the locking jaw 48 is smoothly moved over. Further, the extending length La inwardly in the radial direction of the locking upper surface 38 is set large not only in the entire circumferential direction of the locking upper surface 38 of each locking projection 34 but only in the circumferential intermediate portion 34a. When the locking projection 34 elastically climbs over the locking jaw 48, it is avoided as much as possible that the breaking line 18 is accidentally broken.

  When opening the mouth-and-neck portion 44 to consume the contents, the container lid 2 is rotated in the opening direction, that is, counterclockwise as viewed from above in FIG. Thus, the screwing of the male thread 46 and the female thread 30 is gradually released, and the main portion 20 of the skirt wall 6 is moved upward in the axial direction along with the rotation. On the other hand, the tamper evidence skirt 22 is prevented from moving upward in the axial direction because the locking projection 34 is locked to the locking jaw 48, and thus stress is generated in the bridging portion 26 of the breaking line 18. The bridging portion 26 is broken, and the tamper evidence skirt 22 is separated from the main portion 20 of the skirt wall 6. After the breaking line 18 is broken, the tamper evidence skirt 22 is left on the mouth and neck portion 44, and the top wall 4 of the container lid 2 and the main portion 20 of the skirt wall 6 are free to move upward in the axial direction along with the rotation. Is moved away from the mouth / neck 44 and thus the mouth / neck 44 is opened. If desired, an axial break line is formed in the tamper evidence skirt 22 and when the container neck 44 is opened, the axial break line is broken, while the break line 18 extends in the circumferential direction. One end of the container lid 2 is maintained without being broken, and the tamper evidence skirt 22 is expanded from the endless ring to the end ring, and the entire container lid 2 is detached from the mouth and neck 44 together with the tamper evidence skirt 22. It can also be done.

  In the container lid 2 configured according to the present invention, the length of the locking upper surface 38 extending inward in the radial direction is not the same over the entire circumferential direction in each of the locking projections 34, and the circumferential intermediate portion 34a (therefore, in the illustrated embodiment, the extension length La is set to be larger than the extension length Lb on both sides in the circumferential direction). Has been. Therefore, the break line 18 is broken by rotating the container lid 2 in the opening rotation direction while engaging a finger or an appropriate tool at the end of the tamper evidence skirt 22 and displacing it radially outward. The entire container lid 2 can be removed from the mouth / neck portion 44 without being opened, and the mouth / neck portion 44 can be prevented from being opened illegally.

2: Container lid 4: Top wall 6: Skirt wall 18: Break line 20: Main part 22: Tamper evidence hem part 26: Bridge part 30: Female thread 34: Locking protrusion 34a: Circumferential direction of the locking protrusion Intermediate portion 34b: Both sides in the circumferential direction of the locking projection 36: Locking projection non-existing portion 38: Locking upper surface of the locking projection 40: Tip surface of the locking projection 42: Guide lower surface of the locking projection 44: Mouth and neck 46: Male thread 48: Locking jaw

Claims (5)

A circular skirt wall and a cylindrical skirt wall depending from the peripheral edge of the top wall. A rupture line extending in the circumferential direction is formed in the skirt wall, and the skirt wall is a main skirt wall above the rupture line. And a tamper evidence hem below the break line, and an internal thread is formed on the inner peripheral surface of the main part of the skirt wall, and an inner periphery of the tamper evidence hem The surface is provided with a plurality of locking projections extending in the circumferential direction at intervals in the circumferential direction, and each of the locking projections is made of a synthetic resin having a locking upper surface extending inward in the radial direction. In the container lid,
A radial extension length of the locking upper surface of the circumferential intermediate portion in each of the locking projections is set to be greater than a radial extension length of the locking upper surface on both sides in the circumferential direction. A synthetic resin container lid.   An odd number of the locking projections are arranged at equal intervals in the circumferential direction, and the circumferential length of each of the locking projections is the same, and the diameter of the circumferential intermediate portion of each of the locking projections The synthetic resin container lid according to claim 1, wherein a locking protrusion non-existing portion where the locking protrusion does not exist is located at a position opposite to the direction.   The synthetic resin container lid according to claim 2, wherein five locking protrusions are arranged at equal intervals in the circumferential direction.   The length of the radially inward extension of each of the locking protrusions in each of the locking projections is gradually reduced from the middle in the circumferential direction to both sides in the circumferential direction. The synthetic resin container lid as described.   Each of the locking projections has a guide lower surface extending obliquely outward in a radial direction downward, and a lower edge of the guide lower surface extends from a circumferential middle portion to at least a part of both circumferential side portions. The synthetic resin container lid according to claim 4, which extends horizontally across the container.

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