JP2015077999A - Resin cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin cap which can maintain sufficient intensity, and has high quality guarantee capable of surely preventing mischief.SOLUTION: Plural bridges 11 for coupling a cap body 2 and a tamper-evidence band 3 comprise a preceding breakage bridge group B1 formed of plural slender bridges 19 continuously arranged, and a cross sectional area s1 of a slender coupling part 17 between the respective slender bridges 19 is set to become 0.06 mmto 0.14 mm, and the number of slender bridges 19 is limited. Therefore, sufficient intensity is maintained, and the preceding breakage bridge group B1 is broken preceding to the plural base bridges 18, and difference between a bridge brake angle and a leak angle is expanded, for securing sufficient performance in quality guarantee.

Description

  The present invention relates to a resin cap that is attached to seal a resin bottle or the like for beverages.

  As a resin cap attached to a resin bottle for beverages, one having a tamper evidence performance capable of confirming the presence or absence of unauthorized opening is widely used. If the consumer can confirm that the product has not been opened before purchasing the beverage, damage caused by mischief can be prevented and the quality of the contents can be guaranteed. Such a resin cap includes a cap body attached to the container mouth portion, and a tamper evidence band connected to the open end of the cap body via a plurality of breakable bridges.

  In the above-mentioned resin cap, a plurality of bridges are broken by the opening operation from the mounted state, the plurality of bridges are broken, and the cap body and the tamper evidence band are separated from each other. Therefore, when the break of the bridge is confirmed, it is recognized that the bridge is opened.

  Even if a pulling force begins to act on the bridge after opening the cap, the resin bridge does not break immediately, and the cap body is stretched as the cap body rotates until the cap body rises above the specified amount. . In recent years, interest in quality has been increasing, and therefore further improvement in tamper evidence performance is desired, and characteristics that allow the bridge to be quickly broken when the opening operation is started are required. For example, Patent Document 1 describes a resin cap in which the bridge is ruptured quickly by making the circumferential dimension of the bridge larger than usual and reducing the number thereof.

JP 2010-76797 A

  Even if the opening operation is performed as described above and a tensile force starts to act on the bridge, the resin bridge expands as the cap body rotates. For this reason, there is a concern that the opening operation is suppressed to a certain amount and that the outside air is introduced into the container without breaking the bridge. This occurs because the bridge break angle at which the bridge starts to break is larger than the leak angle at which outside air is introduced. In order to reduce the bridge break angle, it is not possible to obtain sufficient strength with respect to the force acting on the plurality of bridges when the plurality of bridges are narrowed to facilitate breakage. In the resin cap of Patent Document 1, it has been studied to quickly break the bridge, but the difference between the bridge break angle and the leak angle is small, and there is a possibility that sufficient performance cannot be ensured from the viewpoint of quality assurance.

  Therefore, in view of the problems of the prior art, an object of the present invention is to provide a resin cap having high quality assurance that can reliably prevent mischief while maintaining sufficient strength.

In order to achieve the above objective, the following technical measures were taken. That is, the present invention relates to a resin cap comprising a cap body attached to a container mouth portion, and a tamper evidence band connected to the opening end of the cap body through a plurality of bridges that can be broken by a plugging operation. in the plurality of bridges includes preceding break bridge group including a plurality of thin bridges which are successively arranged, wherein the cross-sectional area of the connecting portion of the narrow bridge is a 0.06mm ² ~0.14mm ² And the number of the fine bridges is ½ or less of the number of the plurality of bridges.

In the present invention has been preceding break bridge group is provided comprising a plurality of thin bridges cross-sectional area of the connecting portion is 0.06mm ² ~0.14mm ^2, these fine bridge is easily broken. When a plurality of fine bridges break before other bridges, the bridge break angle becomes very small, and the difference between the bridge break angle and the leak angle can be further widened. In addition, since the number of fine bridges is 1/2 or less than the number of all bridges, a sufficient strength against the force acting on each bridge is maintained. Thereby, sufficient performance can be secured from the aspect of quality assurance while maintaining the strength.

  Although the form of the plurality of bridges is not limited, for example, when the radial dimensions of the connecting portions of the plurality of bridges are the same, the connecting portions of the fine bridges have a width in the circumferential direction: 0.30 mm to 0.55 mm. What is necessary is just to form narrowly. If the circumferential dimension of the connecting portion of each fine bridge is 0.30 mm to 0.55 mm, a good balance between the strength and breakability of each fine bridge can be obtained.

  It is preferable that a plurality of the preceding break bridge groups are provided, and the plurality of preceding break bridges are arranged symmetrically with respect to the midpoint of the cap body. If the plurality of preceding fractured bridge groups are arranged symmetrically with respect to the midpoint of the cap body, the cap body is less likely to twist when the resin cap is gripped and rotated. Therefore, rapid breakage of a plurality of bridges can always be performed stably.

  For example, there are two groups of the preceding break bridges, and each of the preceding break bridge groups includes a resin cap made of the two thin bridges.

  The plurality of bridges may be in any form, for example, forming a plurality of rectangular inner ribs crossing between the cap main body and the tamper evidence band at the boundary between the plurality of bridges. What is necessary is just to let the remaining allowance which put the slit in the inner rib be the connection part of a some bridge | bridging.

  According to the present invention, a narrow bridge having a predetermined cross-sectional area breaks prior to other bridges, so that the bridge break angle is very small, and the difference between the bridge break angle and the leak angle is further widened. Yes. Since the number of fine bridges is ½ or less of the number of the plurality of bridges, a sufficient strength against the force acting on each bridge is maintained. Thereby, it is possible to obtain high quality assurance that can reliably prevent mischief while maintaining sufficient strength.

It is sectional drawing of the resin-made caps which concern on 1st Embodiment of this invention. It is the sectional view on the AA line of FIG. 1 which is the part in which the slit was formed, and the principal part enlarged view. It is the principal part perspective view which looked at the some bridge | bridging and its periphery from the inner side. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a figure corresponding to sectional drawing of FIG. 2 of the resin-made caps concerning 2nd Embodiment of this invention. It is a figure corresponding to sectional drawing of FIG. 2 of the resin-made caps concerning 3rd Embodiment of this invention. It is a figure corresponding to sectional drawing of FIG. 2 of the resin-made caps concerning 4th Embodiment of this invention. It is sectional drawing of the resin caps which show other embodiment.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a resin cap 1 according to a first embodiment of the present invention. 2 is a cross-sectional view taken along the line AA of FIG. 1, which is a portion where a slit is formed. In the following description, the direction corresponding to the top and bottom of FIG. The resin cap 1 is used by being attached to a container mouth portion of a plastic bottle, and is integrally formed of polypropylene by compression molding or injection molding. The material for forming the resin cap 1 is not particularly limited, and polyethylene, polylactic acid, and the like are suitably used in addition to the polypropylene used in the present embodiment.

  The resin cap 1 is composed of a cap main body 2 positioned at the upper portion and a tamper evidence band 3 connected to the lower end of the cap main body 2 and is configured as a one-piece cap having no separate packing. A container mouth portion (not shown) to which the resin cap 1 is attached includes a cylindrical main body portion having a male screw on the outside, a bulging portion whose diameter is expanded below the male screw, a support ring, and the like. The cap body 2 includes a top plate 4 positioned at the uppermost portion, and a side wall portion 5 extending downward from an outer edge 4a of the top plate 4. The top plate 4 is formed in a disk shape. The top plate 4 includes an annular middle leg 6 that is in close contact with the inner peripheral surface of the container mouth portion, and an annular rib 7 that is in contact with the upper end surface of the container mouth portion. The outer legs 8 that are in close contact with the outer peripheral surface of the container mouth are integrally formed. The multiple sealing structure by these seals the container mouth part well, so that the airtightness inside the container is kept high.

  The side wall part 5 of the cap body 2 is formed in a cylindrical shape, and an internal thread 9 is formed on the inner peripheral side thereof to be engaged with the external thread of the container mouth part. The female screw 9 is composed of a plurality of protruding portions 9A provided continuously at a predetermined interval in the circumferential direction, and allows liquid material to pass in the vertical direction. A knurl 10 extending in the vertical direction is formed on the outer peripheral side of the side wall 5.

  A plurality of bridges 11 are formed at predetermined intervals in the circumferential direction at the boundary between the side wall 5 and the tamper evidence band 3. Each of these bridges 11 connects the cap body 2 and the tamper evidence band 3 to each other, and breaks when pulled by a predetermined force. The tamper evidence band 3 is formed in a cylindrical shape whose diameter is slightly increased as it goes downward. On the inner side of the tamper evidence band 3, locking portions 12 extending obliquely upward and inward from the lower end portion 3a are formed at regular intervals in the circumferential direction.

  The locking portion 12 has a substantially square shape in plan view and can be elastically deformed radially inward and radially outward. The locking portion 12 is positioned directly below the bulging portion while being attached to the container mouth portion, and is locked to the bulging portion by the opening operation.

  FIG. 3 is a perspective view of a main part of the plurality of bridges 11 and the periphery thereof viewed from the inside. As shown in FIGS. 2 and 3, 20 first inner ribs 13 and four second inner ribs 14 smaller than the first inner ribs 13 are formed inside the cap body 2. A process of forming the resin cap 1 will be described. First, using a molding machine, the cap body 2 and the tamper evidence band 3 are integrally formed, and a plurality of first inner ribs 13 and a plurality of second inner ribs 14 having a rectangular cross section are formed at a boundary between them. A formed product is obtained. The radial dimension and the circumferential dimension of each first inner rib 13 and each second inner rib 14 are adjusted by setting the mold dimensions. Thereafter, the slit 15 is formed by the slit blade 50 into the portions corresponding to the first inner ribs 13 and the second inner ribs 14 from the radially outer side toward the radially inner side. The slit 15 is inserted in the middle of each first inner rib 13 and each second inner rib 14, and the remaining portion is connected to each base connecting portion (connecting portion) 16 that connects the cap body 2 and the tamper evidence band 3 and each finely connected portion. A plurality of bridges 11 are formed by using the portion (connecting portion) 17.

  Each base connecting portion 16 and each thin connecting portion 17 which are the remaining margins of the slits 15 that have entered the first inner ribs 13 and the second inner ribs 14 have a lateral cross-sectional shape. As shown in FIG. 2, the resin cap 1 of the present embodiment is provided with 24 bridges 11 at equal intervals. Therefore, the angle θ1 formed by two adjacent bridges 11 is 15 °. The number of bridges 11 is not limited, and is, for example, 12 to 30 at regular intervals, and preferably 18 to 25. Therefore, the angle between two adjacent bridges is 30 ° to 12 °.

  A plurality of base bridges 18 are configured by forming each base connecting portion 16 on each first inner rib 13. The number of base bridges 18 in this embodiment is twenty. A plurality of fine bridges 19 are formed by forming each thin coupling portion 17 on each second inner rib 14. The number of fine bridges 19 in this embodiment is four. It is important that the plurality of bridges 11 include a plurality of fine bridges 19 formed in a size different from the others, and the plurality of thin bridges 19 are continuously arranged to form the preceding fracture bridge group B1. ing.

  The pre-breaking bridge group B1 of the present embodiment is composed of two thin bridges 19 and breaks prior to the other base bridges 18 at the time of opening. Each base bridge 18 is a normal bridge larger than each fine bridge 19. The resin cap 1 of the present embodiment is provided with two preceding fracture bridge groups B1 provided symmetrically with respect to the midpoint 30 of the cap body 2. Accordingly, the plurality of bridges 11 of the resin cap 1 are constituted by each preceding fracture bridge group B1 composed of two thin bridges 19 and other normal base bridges 18.

  The number of the pre-breaking bridge group B1 is not limited, and the number of fine bridges 19 constituting the pre-breaking bridge group B1 is not limited as long as it is two or more. The number of fine bridges 19 is less than or equal to the number of all the plurality of bridges 11. The reason is that when the number of the fine bridges 19 exceeds 1/2 with respect to the number of all the plurality of bridges 11, the strength is insufficient with respect to the tensile force acting on the plurality of bridges 11.

FIG. 4 is an enlarged view of a main part of FIG. Cross-sectional area s1 fine connecting portions 17 of the respective fine bridge 19 is 0.06mm ² ~0.14mm ^2, more preferably 0.08mm ² ~0.12mm ^2. Cross-sectional area s2 of the base connection portion 16 of the base bridge 18 is 0.15mm ² ~0.30mm ² about. The cross-sectional area s1 of the thin connecting portion 17 of each thin bridge 19 is set to be about half of the cross-sectional area s2 of the base connecting portion 16 of each base bridge 18. As a result, the plurality of fine bridges 19 are broken prior to the plurality of base bridges 18 during opening. When the cross-sectional area s1 fine connecting portions 17 of the respective fine bridge 19 is less than 0.06 mm ^2, there is a risk that too much off quickly during unplugging, prior to be greater than 0.14 mm ² to a plurality of base bridge 18 This is because it cannot be broken.

  Although the cross-sectional shape of the thin connection part 17 of each thin bridge 19 is not limited, the example formed in the rectangular shape like this embodiment is a representative example. In this embodiment, as shown in FIG. 2, the inner ends 11a of the plurality of bridges 11 are concentric, and the radial dimension r1 of each base connecting portion 16 and each thin connecting portion 17 is 0.20 mm to 0.25 mm and the same. Has been. The circumferential dimension c1 of the base connecting portion 16 of each base bridge 18 is 0.60 mm to 1.10 mm. On the other hand, the circumferential dimension c2 of the thin connecting portion 17 of each narrow bridge 19 is set to 0.30 mm to 0.55 mm, and the width is formed to be about half the circumferential dimension c1 of each base bridge 18. .

  The form of the plurality of bridges is not limited, and may be a type in which the inner ribs are not provided in addition to the inner ribs as in this embodiment. For this purpose, after obtaining a molded product in which the cap main body and the tamper evidence band are integrally molded, a slit that enters radially inward from the outer wall surface may be formed by a slit blade provided with irregularities in the radial direction.

  The operation of each part when the resin cap 1 is attached to the container mouth and the cap body 2 is separated from the tamper evidence band 3 by the opening operation will be described. At the time of closing in the manufacturing process, when the resin cap 1 is turned in the closing direction, it sinks by the action of the screw, and at the same time, the locking portion 12 is elastically deformed from the lower side to the upper side while being closed. Get over the male screw and the bulge. The locking portion 12 elastically returns to its original shape when it has passed over the bulging portion, and is fitted into the lower side of the bulging portion, whereby the mounting of the resin cap 1 is completed.

  At the time of opening, when the resin cap 1 is turned in the opening direction and starts to rise upward by the action of a screw, the locking portion 12 is locked to the bulging portion of the container mouth portion. The tamper evidence band 3 cannot move upward any more, and a tensile force starts to act on the plurality of bridges 11. When the resin cap 1 is further rotated, the plurality of bridges 11 are further pulled as the cap body 2 rises. When the cap main body 2 is raised by a required amount, the plurality of bridges 11 are pulled greatly to be broken. As a result, the cap body 2 is separated from the tamper evidence band 3 and the opening operation is completed.

  In the resin cap 1, the plurality of bridges 11 include a preceding fracture bridge group B <b> 1 including a plurality of thin bridges 19 that are continuously arranged and have a small cross-sectional area. When the resin cap 1 starts to rise upward and a tensile force begins to act on each base bridge 18 and each fine bridge 19 constituting each preceding fracture bridge group B1, each base bridge 18 and each fine bridge 19 are Start to stretch. Each fine bridge 19 is broken before each base bridge 18. After some of the plurality of fine bridges 19 are broken or all of the plurality of fine bridges 19 are broken, the plurality of base bridges 18 are further extended, and all the bridges 18 and 19 are broken. Thus, a part or all of the preceding fracture bridge group B1 can be broken at an early point in time when the opening operation of the resin cap 1 is performed.

If resin cap 1 of the present embodiment, preceding break bridge group B1 comprising a plurality of thin bridges 19 are provided a cross-sectional area s1 is 0.06mm ² ~0.14mm ² fine connecting portion 17, These fine bridges 19 are easier to break than the plurality of base bridges 18. Since each fine bridge 19 is broken before each other base bridge 18, the bridge break angle becomes very small, and the difference between the bridge break angle and the leak angle can be further widened. Further, since the number of the plurality of fine bridges 19 is ½ or less of the number of all the bridges 18, 19, sufficient strength is maintained with respect to the force acting on each bridge 18, 19. Thereby, it is possible to ensure high quality assurance that can reliably prevent mischief while maintaining sufficient strength. In addition, since the circumferential dimension c2 of the thin connecting portion 17 of each fine bridge 19 is 0.30 mm to 0.55 mm, a good balance between the strength and breakability of each fine bridge 19 can be obtained.

  Further, when a plurality of preceding break bridge groups B1 are provided as in the present embodiment, the plurality of preceding break bridges B1 are provided symmetrically with respect to the midpoint 30 of the cap main body 2, so that the resin The cap body 2 is less likely to twist when the cap 1 is gripped and rotated. Therefore, the quick breakage of the plurality of bridges 11 can always be performed stably.

  Other forms of the preceding fracture bridge group are illustrated in FIGS. FIG. 5 is a view corresponding to the cross-sectional view of FIG. 2 of the resin cap 20 according to the second embodiment of the present invention. In the present embodiment, only one preceding break bridge group B2 is provided. This pre-breaking bridge group B <b> 2 includes two thin bridges 19. The number of all the plurality of bridges 11, the shapes and dimensions of the narrow bridges 19 and the base bridges 18, and the shapes and dimensions of the cap body 2 and the tamper evidence band 3 are the same as those in the first embodiment. In the present embodiment, the number of fine bridges 19 is smaller than that in the first embodiment, and the strength is more emphasized.

  FIG. 6 is a view corresponding to the cross-sectional view of FIG. 2 of the resin cap 21 according to the third embodiment of the present invention. In the present embodiment, two preceding fracture bridge groups B3 are provided, and each preceding fracture bridge group B3 is constituted by four thin bridges 19. The number of all the plurality of bridges 11, the shapes and dimensions of the narrow bridges 19 and the base bridges 18, and the shapes and dimensions of the cap body 2 and the tamper evidence band 3 are the same as those in the first embodiment. The two preceding break bridge groups B3 are provided symmetrically with respect to the midpoint 30 of the cap body 2. In the present embodiment, the number of fine bridges 19 is larger than in the first embodiment, and the bridge break angle is further reduced. This widens the difference between the bridge break angle and the leak angle, ensuring higher performance from the standpoint of quality assurance.

  FIG. 7 is a view corresponding to the cross-sectional view of FIG. 2 of the resin cap 22 according to the fourth embodiment of the present invention. In the present embodiment, four preceding fracture bridge groups are provided. The four preceding fracture bridge groups include a first preceding fracture bridge group B41 including three thin bridges 19 and a second preceding fracture bridge group B42 including two narrow bridges 19. The number of all the plurality of bridges 11, the shapes and dimensions of the narrow bridges 19 and the base bridges 18, and the shapes and dimensions of the cap body 2 and the tamper evidence band 3 are the same as those in the first embodiment.

  The two first preceding break bridge groups B41 and the two second preceding break bridge groups B42 are provided symmetrically with respect to the midpoint 30 of the cap body 2, respectively. In the present embodiment, the number of fine bridges 19 is not only larger than that in the first embodiment, but each of the preceding fracture bridge groups B41 and B42 is arranged at four locations every 90 ° along the circumferential direction. . As a result, the bridge break angle is further reduced to ensure higher performance in terms of quality assurance. At the same time, a good balance of the tensile force acting when each preceding break bridge group B41, B42 breaks is obtained, and each preceding break bridge group B41, B42 can be reliably and quickly broken. In addition, since a good balance of tensile force can be obtained, the cap body 2 can be prevented from being twisted, and the user's sense of opening operation can be improved.

  The resin cap of each embodiment exemplifies the resin cap according to the present invention, and the shape, dimensions, constituent resin, molding method and the like of each part may be appropriately changed. For example, the present invention may be applied to the resin cap 23 shown in FIG. 8 provided with a separate packing. In this example, a packing 24 for sealing the container is provided inside the top plate 4. The packing 24 includes a disk-like plate-like portion 25 along the lower surface 4 b of the top plate 4, an annular side seal 26 that bends downward from the outer peripheral portion 25 a of the plate-like portion 25, and a lower surface from the lower surface 25 b of the plate-like portion 25. It has a cylindrical middle leg 27 extending toward it. The side seal 26 enters between the upper end portion of the container mouth portion and the side wall portion 5 of the cap body 2, and the middle foot 27 is in close contact with the inner surface of the upper end portion of the container mouth portion. The multiple sealing structure by these seals the container mouth part well, so that the airtightness inside the container is kept high.

  The number of the pre-breaking bridge groups, the arrangement, and the number of fine bridges may be changed. The shape of each bridge is not limited to a square cross section, and may be a triangular cross section, another polygonal cross section, or a circular cross section. In these cases, the degree of penetration of the slit is adjusted according to each shape so that the required strength can be maintained, and the circumferential dimension and the radial dimension of the thin coupling part and the base coupling part are determined. The cross-sectional shapes of the fine connecting portion of the fine bridge and the base connecting portion of the base bridge may be different. For example, the circumferential dimension and the radial dimension of the thin coupling parts of the plurality of fine bridges are made different from each other, and the circumferential dimension and the radial dimension of the thin coupling parts of the plurality of thin bridges and the base coupling part of the plurality of base bridges. And making them different from each other. The container to which the resin cap of the present invention is applied is not limited, and the shape of the container mouth is not limited.

DESCRIPTION OF SYMBOLS 1, 20, 21, 22, 23 Resin cap 2 Cap body 3 Tamper evidence band 4 Top plate 5 Side wall part 6 Middle foot 7 Annular rib 8 Outer foot 9 Female screw 11 All several bridges 12 Locking part 13 In 1st Rib 14 Second inner rib 15 Slit 16 Base connecting part 17 Thin connecting part 18 Base bridge 19 Fine bridge B1, B2, B3 Pre-breaking bridge group B41 First pre-breaking bridge group B42 Second pre-breaking bridge group

Claims (5)

In a resin cap comprising a cap body attached to the container mouth portion, and a tamper evidence band connected to the open end of the cap body via a plurality of bridges that can be broken by an opening operation,
Wherein the plurality of bridges includes preceding break bridge group including a plurality of thin bridges which are successively arranged, wherein the cross-sectional area of the connecting portion of the narrow bridge are a 0.06mm ² ~0.14mm ^2, The resin cap, wherein the number of the fine bridges is ½ or less of the number of the plurality of bridges.   The radial direction dimensions of the connecting portions of the plurality of bridges are the same, and the connecting portions of the thin bridges are formed to be narrow with a circumferential dimension of 0.30 mm to 0.55 mm. Item 2. A resin cap according to Item 1.   The resin according to claim 1 or 2, wherein a plurality of the preceding break bridge groups are provided, and the plurality of preceding break bridge groups are arranged symmetrically with respect to a midpoint of the cap body. Made of cap.   4. The resin cap according to claim 3, wherein there are two groups of the preceding fracture bridges, and each of the preceding fracture bridge groups is composed of the two thin bridges.   The plurality of bridges are formed with a plurality of rectangular inner ribs crossing between the cap main body and the tamper evidence band, and a remaining margin obtained by slitting the plurality of inner ribs. It is comprised by setting it as a connection part, The resin-made caps in any one of Claims 1-5 characterized by the above-mentioned.

Images