JP6534501B2 - Plastic container lid - Google Patents

Description

  The present invention comprises a synthetic resin container lid having tamper-evident properties, more specifically, a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall, and a circumferentially extending fracture in the skirt wall A line is formed, and the skirt wall is divided into a main part above the breaking line and a tamper-evidence foot below the breaking line, and a female screw is formed on the inner circumferential surface of the main part of the skirt wall A strip is formed, and on the inner circumferential surface of the tamper evident foot portion, a plurality of locking projections extending circumferentially at intervals in the circumferential direction are disposed, each of the locking projections being radially inward The present invention relates to a synthetic resin container lid having a locking upper surface extending therefrom.

  As is well known, a synthetic resin container lid for a container for a beverage having a cylindrical neck and neck on which an external thread and a locking jaw located below the external thread are disposed. For example, as disclosed in Patent Document 1 below, a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall are provided, and the skirt wall is formed with a circumferentially extending breaking line. The synthetic resin container lid, in which the skirt wall is divided into a main part above the breaking line and a tamper evidence part below the breaking line, is widely put to practical use. An internal thread is formed on the inner peripheral surface of the main portion of the skirt wall. A plurality of locking projections extending in the circumferential direction at intervals in the circumferential direction are disposed on the inner peripheral surface of the tamper evident foot, and the locking projections extend 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 closing rotation direction, that is, clockwise as viewed from above, and the female thread of the container lid is screwed on the male screw of the mouth and neck. It is worn on the neck and neck by screwing the strip. The locking projection formed on the inner circumferential surface of the tamper-evident foot portion is elastically passed over the locking jaw portion of the neck and is positioned therebelow. When opening the neck of the container in order to consume the contents of the container, the container lid is rotated in the opening rotational direction, that is, counterclockwise as viewed from above. As a result, the screwing of the female screw to the male screw is gradually released, and the top wall of the container lid and the main part of the skirt wall do not rise with the rotation in the opening direction, but the tamper evident skirt By locking the locking upper surface of the locking projection formed on the circumferential surface to the locking jaw of the neck and neck, the rise is blocked, thus generating stress in the breaking line and breaking the breaking line, tampering The evident foot is separated from the main part of the skirt wall. After that, the tamper evident's skirt is left on the neck, and the top wall and the main part of the skirt wall are freely lifted with the rotation in the opening rotational direction and disengaged from the neck. Will be opened. In the synthetic resin container lid in which the fracture line extending in the axial direction is formed in the bottom portion of the tamper evident, the fracture line of the fracture line extending in the circumferential direction is broken not partially along the circumferential direction but partially Without breaking, the axially extending break line formed in the tamper evident skirt is broken so that the tamper evident skirt is converted from an endless annular form to an endless belt form, thereby causing the oral cervix The locking projections are released from the locking jaws of the head, and thereafter the entire container lid including the tamper evident foot is freely lifted with rotation in the opening rotational direction and is released from the neck The mouth and neck are opened.

JP, 2011-143942, A

  According to the inventor's experience, according to the conventional synthetic resin container lid as described above, (1) a finger or an appropriate tool is locked at the end of the tamper-evident skirt to radially outward By rotating the container lid in the opening and rotating direction while displacing it, there is no risk that the entire container lid can be detached from the mouth and neck without opening the fracture line and the mouth and neck being unfairly opened. (2) When attaching the container lid to the mouth and neck of the container, the locking projections disposed on the inner circumferential surface of the tamper evident's foot, in particular, resiliently ride over the locking jaw of the mouth and neck At the same time, there is a problem to be solved that the break line may be broken accidentally.

  The present invention has been made in view of the above-mentioned facts, and the main technical problem thereof is to reliably prevent the opening of the mouth and neck from being illegally opened as described above, and to prevent the container lid from covering the mouth and neck It is an object of the present invention to provide a new and improved synthetic resin container lid in which the breakage line is prevented as much as possible from being broken accidentally when mounting the container.

As a result of intensive investigations, the inventors of the present invention found that if the radial inward extension length of the locking upper surface in each of the locking protrusions is relatively long, the mouth and neck is unfairly opened as described above. However, in view of the fact that the tendency of the broken line to be broken accidentally increases when attaching the container lid to the mouth and neck, each form of the locking means is circumferentially intermediate with not greater than the extension length of the radially inward engaging the upper surface in extending length of the section to the locking top radially inward of the circumferential sides, circumferential in each of the locking projections direction extending end of the intermediate portion to the locking top radially inward of a convex arc, extending length of the radially inward is caused to gradually decrease toward the circumferential center in the circumferential direction on both sides It is seen that it is possible to achieve the principal object by a unique form and It was.

That is, according to the present invention, as a synthetic resin container lid which achieves the above-mentioned main technical problems,
It has a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall, and the skirt wall is formed with a circumferentially extending breaking line, the skirt wall being a main line above the breaking line Section and a tamper-evident skirt below the breaking line, and a female screw is formed on the inner circumferential surface of the main section of the skirt wall, the inner periphery of the tamper-evident skirt The surface is provided with three or more odd number of locking projections extending in the circumferential direction at equal intervals in the circumferential direction, and each of the locking projections has a locking upper surface extending radially inward. A locking projection non-presence portion in which the circumferential length of each of the locking projections is the same, and the locking projection does not exist at a diametrically opposite portion of a circumferential intermediate portion of each of the locking projections There located, in the diametrically opposite portion of the circumferential side portions of the respective engaging projections, respectively, engaging projections Circumferential both sides of the locking projection positioned on both sides in the peripheral direction of the missing portion, in plastic container closure which one is located adjacent to the engaging projection absence unit,
The radially inward extending length of the locking upper surface of the circumferential middle portion in each of the locking projections is greater than the radially inward extending length of the locking upper surface in both circumferential side portions Is set,
The radially inward extending end edge of the locking upper surface of the circumferential middle portion of each of the locking projections is a convex arc, and the locking upper surface of the circumferential middle portion of each of the locking protrusions is The radially inward extension length is gradually reduced from the circumferential center to both circumferential directions,
Each of the locking projections has a guiding lower surface which extends downwardly and radially outward and inclined, and the lower edge of the guiding lower surface extends from the circumferential middle to at least a part of the circumferential sides. Extend horizontally across,
A container made of synthetic resin is provided.

Preferably, five of the locking projections are arranged at equal intervals in the circumferential direction .

In plastic container closure of the present invention, the radial lock top extending the length of the radially inward locking the upper surface of the circumferential direction intermediate portion of each of the locking projections in the circumferential direction both side portions inward Since it is set to be larger than the extension length, it is effective to lock a finger or an appropriate tool at the end of the tamper-evident skirt to displace it radially outward to break the lock. To prevent. On the other hand, the radially inward extension length of the locking upper surface is set large only at the circumferential middle portion of each of the locking protrusions, and the locking upper surface of the circumferential middle portion of each of the locking protrusions is The radially inward extending end edge is a convex arc, and the radially inward extending length of the locking upper surface of the circumferential middle portion in each of the locking projections is circumferentially from the circumferential center to both sides in the circumferential direction Since the locking projection non-presence portion in which the locking projection is not present is located at the diametrically opposite portion of the circumferential middle portion of each of the locking projections which is gradually reduced toward the container lid, the container lid is The breaking line is broken by accident when attaching, especially when the locking projections disposed on the inner circumferential surface of the tamper-evident foot part elastically ride over the locking jaw part of the neck and neck. It is avoided as much as possible.

BRIEF DESCRIPTION OF THE DRAWINGS The front view which shows a preferable embodiment of the synthetic resin container lid comprised according to this invention in the cross section in part. 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.

  The preferred embodiments of the synthetic resin container lid constructed in accordance with the present invention will be described in more detail with reference to the accompanying drawings.

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

  The skirt wall 6 has a relatively thick upper portion 14 and a relatively thin lower portion 16. The fracture 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 the main portion 20 above the fracture line 18 and the tamper-evidence foot 22 below the fracture line 18. It is done. In the illustrated embodiment, the breaking line 18 comprises a plurality of circumferentially extending slits 24 and a plurality of bridges 26 remaining between the slits 24 and the tamper shrimp Dent foot 22 is connected to main part 20 via a plurality of bridges 26.

  On the outer peripheral surface of the main portion 20 of the skirt wall 6, a non-slip knurling 28 is formed which has an uneven shape alternately seen in the circumferential direction. The inner circumferential surface of the main portion 20 of the skirt wall 6 is formed with a plurality of notches 32 extending in the axial direction together with the female thread 30.

Five locking projections 34 are disposed at equal intervals in the circumferential direction on the inner circumferential surface of the tamper-evident foot portion 22, and the circumferential length of each locking projection 34 is substantially the same. The locking projection non-existing portion 36 exists on the diametrically opposite side of the circumferential intermediate portion 34 a of each locking projection 34.

Continuing with reference to FIGS. 2 and 3 in conjunction with FIG. 1, each of the locking projections 34 has a radially inward extending locking upper surface 38, and a tip surface which is generally semi-circular in longitudinal cross section. 40 and a downwardly directed guiding lower surface 42 extending radially outwardly. Further, in the container lid 2 configured according to the present invention, in each of the locking projections 34, the radially inward extension length of the locking upper surface 38 is not the same over the entire circumferential direction, but the circumferential direction extension length La in the intermediate portion 34a, together are greater than the extension length Lb in the circumferential direction both side portions, extending length La in the circumferential direction intermediate portion 34a of the locking top 38, the circumferential direction It is important to be gradually reduced from the middle to both circumferential directions. Extending length Lb of the radially inwardly of the locking top 38 in the circumferential direction sides 34b are gradually being brought reduced with distance from the circumferential direction intermediate portion 34a in the circumferential direction, the circumferential outer side end (circumferential direction intermediate In the unconnected end with the part 34, it is substantially zero. Radial extension of the locking upper surface at both circumferential ends of the circumferential intermediate portion 34a and radial extension of the locking upper surface at the circumferential inner end of the circumferential side portions 34b (connection end with the circumferential intermediate portion 34a) The lengths are identical. In the illustrated embodiment, the lower edge of the guiding lower surface 42 of each of the locking projections 34 extends substantially horizontally from the circumferential middle portion 34a to a portion (i.e., the inner half) of the side portions 34b. (See Figure 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 circumferential outer end.

  The mouth and neck 44 of the container is also shown in FIG. The mouth and neck 44 of the container, which can be made of a suitable synthetic resin such as polyethylene terephthalate, glass or sheet metal, is generally cylindrical in shape and male screw 46 and male screw on the outer peripheral surface of the mouth neck 44 A locking jaw 48 located below 46 is formed. The locking jaws 48 have an arcuate upper surface with a gradually increasing outer diameter downwardly and a lower surface extending substantially horizontally. Also disposed on the outer peripheral surface of the neck and neck portion 44 is a support ring 50 located below the locking jaws 48 (the support ring 50 is used to convey the container as is well known to those skilled in the art) ing.

  When the container lid 2 is attached to the mouth and neck 44 after the contents are filled in the container and the mouth and neck 44 is sealed, the container lid 2 is fitted on the mouth and neck 44 and the container lid 2 is closed. The female screw 30 of the container lid 2 is screwed onto the male screw 46 of the mouth and neck 44 by rotating in the direction of rotation, clockwise as viewed from above in FIG. When the female screw 30 is screwed to the male screw 46 until the state shown in FIG. 1, the inner seal piece 8 of the container lid 2 intrudes into the mouth and neck 44 and closely contacts the inner circumferential surface of the mouth and neck 44 The annular projection 12 is brought into close contact with the top surface of the neck 44, and the outer seal piece 10 is brought into close contact with the outer circumferential surface of the neck 44, thus sealing the neck 44.

If description is continued with reference to FIG. 1, when attaching the container lid 2 to the opening and neck 44 and sealing the opening and neck 44, it is arrange | positioned by the inner peripheral surface of the tamper evidend part 22 The locking projection 34 resiliently rides over the locking jaw 48 of the neck 44 and is positioned below the locking jaw 48. At this time, the locking projection 34 is gradually displaced radially outward by the guiding action of the guide lower surface 42 of the locking projection 34 and smoothly rides over the locking jaw 48. Further, the radially inward extension length La of the locking upper surface 38 is set to be large not only in the entire circumferential direction of each locking upper surface 38 of each locking projection 34 but only in the circumferential intermediate portion 34 a , Since the radially inward extension length La of the circumferential intermediate portion 34a is gradually reduced from the circumferential center toward both circumferential directions , the locking projections 34 elastically lock the locking jaws 48. It is avoided as much as possible that the break line 18 is broken accidentally when crossing over.

  When opening the neck 44 in order to consume the contents, the container lid 2 is rotated in the opening direction, that is, counterclockwise as viewed from above in FIG. As a result, the screwing between the male screw 46 and the female screw 30 is gradually released, and the main portion 20 of the skirt wall 6 is moved axially upward with rotation. On the other hand, the tamper-evidence foot 22 is prevented from moving upward in the axial direction because the locking projection 34 is locked to the locking jaw 48, thus generating stress in the bridge 26 of the breaking line 18 The bridge 26 is broken, and the tamper evident foot 22 is separated from the main portion 20 of the skirt wall 6. After the breaking line 18 is broken, the tamper evident foot 22 is left on the neck 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 with rotation. To be removed from the neck 44 and thus the neck 44 is opened. If desired, an axial break line is formed in the tamper-evidence foot 22 and when opening the neck 44 of the container the break line is broken and the break line 18 extends in the circumferential direction. Is maintained without breaking at one end thereof, the tamper evident eaves portion 22 is expanded from an endless annular shape to an endless annular shape, and the entire container lid 2 together with the tamper evident formed portion 22 is released from the neck 44 You can do it as well.

In the container lid 2 configured in accordance with the present invention, in each of the locking projections 34, the radially inward extension length of the locking upper surface 38 is not the same over the entire circumferential direction, 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 on the portion located on the diametrically opposite side to the locking projection non-existing portion 36) The radially inward extension length La of the circumferential intermediate portion 34a is gradually reduced from the circumferential center to both circumferential sides . Therefore, the breaking line 18 is broken by rotating the container lid 2 in the opening rotational direction while displacing the finger or an appropriate tool at the end of the tamper evident foot 22 and displacing it radially outward. It is sufficiently reliably prevented that the whole of the container lid 2 is detached from the mouth and neck 44 and the mouth and neck 44 is unfairly opened.

2: Container lid 4: Top wall 6: Skirt wall 18: Broken line 20: Main part 22: Tamper evident foot 26: Bridge 30: Female thread 34: Locking projection 34a: Circumferential direction of locking projection Middle part 34b: circumferentially opposite side parts of the locking projection 36: locking projection non-existing section 38: locking top surface of the locking projection 40: tip surface of the locking projection 42: guiding lower surface of the locking projection 44: mouth and neck 46: Male thread 48: Locking jaw

Claims (2)

It has a circular top wall and a cylindrical skirt wall depending from the periphery of the top wall, and the skirt wall is formed with a circumferentially extending breaking line, the skirt wall being a main line above the breaking line Section and a tamper-evident skirt below the breaking line, and a female screw is formed on the inner circumferential surface of the main section of the skirt wall, the inner periphery of the tamper-evident skirt The surface is provided with three or more odd number of locking projections extending in the circumferential direction at equal intervals in the circumferential direction, and each of the locking projections has a locking upper surface extending radially inward. A locking projection non-presence portion in which the circumferential length of each of the locking projections is the same, and the locking projection does not exist at a diametrically opposite portion of a circumferential intermediate portion of each of the locking projections There located, in the diametrically opposite portion of the circumferential side portions of the respective engaging projections, respectively, engaging projections Circumferential both sides of the locking projection positioned on both sides in the peripheral direction of the missing portion, in plastic container closure which one is located adjacent to the engaging projection absence unit,
The radially inward extending length of the locking upper surface of the circumferential middle portion in each of the locking projections is greater than the radially inward extending length of the locking upper surface in both circumferential side portions Is set,
The radially inward extending end edge of the locking upper surface of the circumferential middle portion of each of the locking projections is a convex arc, and the locking upper surface of the circumferential middle portion of each of the locking protrusions is The radially inward extension length is gradually reduced from the circumferential center to both circumferential directions,
Each of the locking projections has a guiding lower surface which extends downwardly and radially outward and inclined, and the lower edge of the guiding lower surface extends from the circumferential middle to at least a part of the circumferential sides. Extend horizontally across,
Container lid made of synthetic resin. The synthetic resin container lid according to claim 1, wherein five locking projections are arranged at equal intervals in the circumferential direction.

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