JPH10175656A - Container lid made of synthetic resin, equipped with tamper evident characteristic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a bridging part from breaking by a method wherein a high strength bridging part is arranged on the upper end of an axial directional breaking means which is constituted of a slit which extends from the upper end of a tamper evident skirt part to the lower end, and the high strength bridging part is extended in the circumferential direction from the axial directional breaking means or one end which is close by. SOLUTION: On the mouth part 42 of a container, a male thread 44 and an annular engaging jaw part 46 are formed. After filling a content in the container, a container lid 2 is fitted on the mouth part 42. The container lid 2 is fitted on the mouth part 42, and a female thread 18 is engaged with the male thread 44, and the container lid 2 is lowered. A flap piece 28 which is formed on a tamper evident skirt part 12 of the container lid 2, is engaged with the engaging jaw part 46. On the tamper evident skirt part 12, a slit which constitutes an axial directional breaking means 34, is expanded. For the container lid 2, a first high strength bridging part 36c is arranged on one side of the slit when seen in the circumferential direction, and a second high strength bridging part 36d is arranged on the other side. By this method, when the container lid 2 is fitted, bridging parts 36a, 36b are surely prevented from breaking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for beverages and the like, in which a male screw and a locking jaw located below the male screw are formed on the outer peripheral surface of the mouth and neck. The present invention relates to a synthetic resin container lid applied to a container, and more particularly, to a synthetic resin container lid having a tamper-evident characteristic (a characteristic in which traces remain when the container lid is operated to add fraud).

[0002]

2. Description of the Related Art As is well known, a male screw and a locking jaw located below the male screw are formed on an outer peripheral surface of a mouth and neck portion. As a container lid applied to a resin container, for example, Japanese Patent Publication No. 58-32
No. 103, Japanese Patent Publication No. Sho 62-18421, Japanese Patent Application Laid-Open No. 4-311461, Japanese Utility Model Application Laid-Open No. 6-54544, and Japanese Patent Application Laid-Open No. 8-80957, having a tamper-evident property. Resin container lids are widely used in practice. Such a container lid has a circular top wall and a skirt wall hanging from the top wall.
The skirt wall is formed with a circumferential breaking means extending in the circumferential direction, and the skirt wall is divided into a main portion above the circumferential breaking means and a tamper-evident hem below the circumferential breaking means. I have. On the inner peripheral surface of the main part of the skirt wall,
A female thread is formed which cooperates with a male thread formed on the mouth and neck of the container. Locking means cooperating with a locking jaw formed on the mouth and neck of the container is formed on the inner peripheral surface of the tamper-evident skirt. The circumferential breaking means includes a plurality of bridging portions which are arranged at intervals in the circumferential direction and connect the tamper-evident hem to the main portion of the skirt wall. One of them is a high-strength bridge having a large cross-sectional area. An axial breaking means is formed at the tamper-evident foot. The axial breaking means may be based on a score formed by reducing the thickness of the material or on a slit containing discontinuities (by completely cutting the material in its thickness direction or by reducing the thickness of the material during molding). Groove formed by not existing in the entire direction.

[0003] When a container lid is attached to the mouth and neck of a container to seal it, the container lid is fitted over the mouth and neck and rotated in the closing direction. Screw the female thread. The container lid is lowered in accordance with the progress of the screwing of the male thread and the female thread, and the locking means of the container lid elastically climbs over the locking jaw of the mouth and neck and locks on the lower surface thereof. I'm sullen. To open the mouth and neck of the container, the container is rotated in the opening direction. Thus, the female thread of the container lid is moved along the male thread of the mouth and neck, and the screwing of both is released, so that the container lid is raised in accordance with the rotation in the opening direction. However, since the locking means formed on the tamper-evidence hem is locked to the locking jaw of the mouth and neck, the tamper-evidence hem is prevented from rising, and as a result, A stress is generated in the breaking means, and the bridging part in the circumferential breaking means is broken except for one high-strength bridging part. Furthermore, it is intended that the following behavior is generated: That is, the score in the axial breaking means formed on the tamper-evidence hem is broken, or the discontinuous portion of the slit is ruptured, and thus the tamper-evidence hem is unfolded in a band shape, thereby the locking jaw. Then, the locking of the locking means is released, and after that, the entire container lid is raised in accordance with the rotation in the opening direction and detached from the mouth and neck.

[0004]

According to the experience of the present inventors, the following problems exist in the conventional container lid as described above. That is, when opening the mouth and neck of the container, the score in the axial breaking means formed on the tamper-evidence hem is broken, or the discontinuous portion of the slit is broken, and the tamper-evidence hem is broken. Are intended to be deployed in a strip, but instead of breaking the score or discontinuous part of the slit in the axial breaking means, one high strength bridge in the circumferential breaking means is broken, thus The endless annular tamper is completely separated from the main part of the skirt wall because the discontinuous portion of the score or slit remains without being broken, and the endless annular tamper is attached to the mouth and neck of the container. The rest of the container lid is removed from the mouth and neck, leaving the evidence hem behind. When such a situation occurs, from the viewpoint of so-called material collection of waste or in order to reuse the container, the annular endless tamper-evident hem is developed in a belt shape with an appropriate cutting tool. It is necessary to perform the operation of removing from the mouth and neck of the container separately.

In order to solve the above-mentioned problem in the conventional container lid, the axial breaking means provided on the tamper-edent hem portion extends continuously from the upper end of the tamper-evidence hem portion to the substantially lower end. It is intended to consist of a slit. Thus, when the bridging portion in the circumferential breaking means is broken except for one high-strength bridging portion when opening the mouth and neck of the container, the tamper-evident hem is inevitably formed into a belt-like shape. The container is deployed, and thus ensures that the entire container lid is released from the mouth and neck of the container. However, simply
When the axial breaking means disposed on the tamper-evident hem is constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper-evidence hem, when attaching the container lid to the mouth and neck of the container, In particular, when the locking means of the container lid elastically crosses over the locking jaw of the mouth and neck, the tamper-evident hem is expanded at the portion where the axial breaking means exists, and as a result, There is a tendency for an unacceptable situation in which at least some of the plurality of bridges in the breaking means are broken.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and its main technical problem is that an axial breaking means provided on a tamper-edent hem is substantially vertically moved from the upper end of the tamper-evidence hem. It is composed of slits extending continuously to the end, so that if the bridging part in the circumferential breaking means is broken except for one high-strength bridging part, the tamper-evident hem will necessarily be strip-shaped. Despite the deployed form, when the container lid is attached to the mouth and neck of the container, the tamper-evident hem is expanded at the portion where the axial breaking means is present, and as a result, An object of the present invention is to provide a new and improved synthetic resin container lid in which at least some of the plurality of bridge portions in the direction breaking means are sufficiently reliably prevented from being broken.

[0007]

In order to solve the above-mentioned main technical problems, according to the present invention, two of a plurality of bridging portions are made into high-strength bridging portions having a large cross-sectional area. The two high-strength bridging portions are disposed on both sides of the upper end of the axial breaking means constituted by a slit extending from the upper end of the tamper-evident hem to the substantially lower end, and one of the high-strength bridging portions is The high-strength bridging portion extends from the upper end of the axial breaking means to one end in the circumferential direction, and the other high-strength bridging portion extends from the upper end of the axial breaking means to the other end in the circumferential direction. .

That is, according to the present invention, as a synthetic resin container lid for solving the above-mentioned main technical problems, a male screw and a member located below the male screw are provided on the outer peripheral surface of the mouth and neck. A synthetic resin container lid having a tamper-evident property, which is applied to a container having a tongue portion, comprising a top wall and a skirt wall hanging down from the top wall. Is formed with a circumferential breaking means extending in the circumferential direction, and the skirt wall has a main portion above the circumferential breaking means and a tamper-evident hem below the circumferential breaking means. A female thread cooperating with the male thread of the mouth and neck is formed on the inner peripheral surface of the main part of the skirt wall, and the inner peripheral surface of the tamper evidence hem is formed on the inner peripheral surface of the skirt wall. A locking means cooperating with the locking jaw of the mouth and neck is formed, and the circumferential breaking means is circumferential. A plurality of bridging portions, spaced apart from each other, connecting the tamper-evident skirt to the main portion of the skirt wall, one of the bridging portions having a large cross-sectional area A first high-strength bridging portion, wherein the axial rupture means is disposed on the tamper-evident skirt; and the axial rupture means is an upper end of the tamper-evident hem. A plurality of bridging portions extending from the first high-strength bridging portion to the second high-strength bridging portion having a large cross-sectional area in addition to the first high-strength bridging portion. The first high-strength bridging portion and the second high-strength bridging portion are disposed on both sides of the axial breaking means as viewed in the circumferential direction, and include the first high-strength bridging portion; The strength bridging portion extends circumferentially from the upper end of the axial breaking means or from one end close to the upper end, The second high-strength bridging portion extends circumferentially from the upper end of the axial breaking means or from one end adjacent thereto in the other circumferential direction. The female screw is screwed to the male screw to lock the locking means. When the female thread and the male thread are disengaged from the mouth and neck by being engaged with the mouth and neck by being locked to the locking jaw, the first Wherein at least one of the high-strength bridging portion and the second high-strength bridging portion is broken.

[0009] The cross-sectional area of the first high-strength bridge is larger than the cross-sectional area of the second high-strength bridge. When disengaging from the mouth and neck, the second high-strength bridge is broken, but the first high-strength bridge remains without breaking, and the tamper-evident hem is strip-shaped. And the locking means is released from the locking jaw, and the entire container lid including the tamper-evident hem is detached from the mouth and neck. The cross-sectional area of the first high-strength bridge is from 1.50 to 4.50 mm ² , and the cross-sectional area of the second high-strength bridge is from 0.80 to 2.20 mm ^2. It is suitable.
Preferably, the first high-strength bridging portion is formed in the axial direction when viewed in the container cover rotating direction when the female screw and the male screw are unscrewed and detached from the mouth and neck. Located in front of the breaking means, the second high-strength bridge is located behind the axial breaking means. The one end of the first high-strength bridge and the one end of the second high-strength bridge are located at a distance of 1.00 to 3.00 mm from an upper end of the axial breaking means. Is preferred. In a preferred embodiment, the tamper-evident hem is provided with a thin curl extending from the lower end thereof, and the slit constituting the axial breaking means extends only partially or completely into the thin curl. Not.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a synthetic resin container lid constructed in accordance with the present invention will be described below in more detail with reference to the accompanying drawings.

FIG. 1 illustrates a preferred embodiment of a synthetic resin container lid constructed in accordance with the present invention. A container lid, generally designated by the reference numeral 2, which can be formed of a suitable synthetic resin such as polypropylene or hard polyethylene, has a circular top wall 4 and a substantially cylindrical skirt wall 6 hanging from the periphery of the top wall 4. I have it. The skirt wall 6 is formed with a circumferential breaking means 8 (the circumferential breaking means 8 will be described in more detail later). It is divided into a tamper-evident foot portion 12 below the direction breaking means 8.

On the outer peripheral surface of the main portion 10 of the skirt wall 6, a conical portion 14 whose outer diameter gradually increases downward is formed near the lower end thereof. Main part 1 of skirt wall 4
The lower end of the zero, that is, the portion below the truncated cone-shaped portion 14 and the outer peripheral surface of the tamper-evident hem portion 12 following this are also made to have a conical shape whose outer diameter is slightly increased gradually but gradually downward. I have. In a portion above the conical portion 14 on the outer peripheral surface of the main portion 10, a concavo-convex shape 16 for preventing a finger hung thereon from slipping is formed. A female thread 18 is formed on the inner peripheral surface of the main part 10. The female thread 18 is formed with a notch 20 extending in the axial direction at intervals in the circumferential direction. Notch 2
0 constitutes a so-called air passage when the mouth and neck of the container is opened. On the inner peripheral surface of the main portion 10, an annular ridge 22 is further formed at the upper end thereof. And such annular ridge 22
A sealing liner 24 formed separately from the main body of the container lid 2 is provided in a space defined by the inner wall of the top wall 4. The sealing liner 24 can be conveniently formed by supplying a softened and molten synthetic resin material to the inner surface of the top wall 4 and compressing the synthetic resin material with a pressing tool. The synthetic resin material for the sealing liner 24 is preferably a relatively soft synthetic resin such as soft polyethylene.

An upper portion of the inner peripheral surface of the tamper-evident hem portion 12 has an annular shoulder surface 26 facing downward. Below the annular shoulder surface 26, a plurality of flap pieces 28 are formed on the inner peripheral surface of the tamper-evident hem portion 12 at equal intervals in the circumferential direction. As will be apparent from the following description, the flap piece 28 constitutes a locking means which is locked to a locking jaw formed on the mouth and neck of the container. Each of the flap pieces 28
From the base edge 30 connected to the inner peripheral surface of the tamper-evident hem portion 12, the direction of closing rotation of the container lid when the container lid 2 is mounted on the mouth and neck of the container, that is, clockwise as viewed from above in FIG. , And project inward in the radial direction while being inclined in the opposite direction. Each base edge 30 itself of the flap piece 28 also extends downward while being inclined in a direction opposite to the closing rotation direction of the container lid 2. At the lower end of the tamper-evident hem portion 12, a thin curl 32 extending in an arc shape inward in the radial direction is attached.

Referring to FIG. 2 in conjunction with FIG. 1, the tamper-evident skirt portion 12 is provided with an axial breaking means 34. This axial breaking means 34
It is important that the tamper-evident hem 12 is formed of a slit extending continuously from the upper end to the substantially lower end. In the illustrated embodiment, the slits forming the axial breaking means 34 are tamper-evident hem portions 1.
2 extends downward from the upper end of the thin curl 32 to the upper end of the thin curl 32, but does not extend at all or only partially extends to the thin curl 32. Depending on the cutting error in the forming operation, the slit may be partially extended into the thin curl 32 or not extended at all). If desired, a slit constituting the axial breaking means 34 can be extended to the tip of the thin curl 32.
The slit constituting the axial breaking means 34 is located between the flap pieces 28 without intersecting with the base edge 30 of the flap piece 28 formed on the inner peripheral surface of the tamper-evident hem portion 12. Is preferred. If desired, instead of extending substantially vertically (ie, substantially parallel to the central axis), the slits forming the axial breaking means 34 may be somewhat inclined, for example as shown in FIG. The flap piece 28 may extend substantially parallel to the base edge 30.

As can be clearly understood by referring to FIG. 2, the above-mentioned circumferential breaking means 8 comprises a plurality of bridging portions 36a, 36b, 3
6c and 36d. In the cross-sectional view in which the circumferential breaking means 8 is provided, the bridging portions 36a, 3b
In regions other than 6b, 36c and 36d, the main portion 10 of the skirt wall 6 and the tamper-evident hem 12 are preferably separated from each other by cutting.
Therefore, the tamper-evident hem 12 has a bridging portion 36a,
It is connected to the main part 10 via 36b, 36c and 36d. A plurality of the bridging portions 36a are arranged at equal intervals in the circumferential direction (except for a region where the first high-strength bridging portion 36c mentioned later is arranged), and have substantially the same cross-sectional shape. Having. A plurality of bridging portions 36b are also arranged at equal intervals in the circumferential direction (except for a region where the first high-strength bridging portion 36c mentioned later is arranged), and have substantially the same cross-sectional shape. Having. Bridge 36a and Bridge 36b
Are arranged in the same number, and each of the bridging portions 36b is located in the middle of the adjacent bridging portion 36a. The cross-sectional area of each of the bridging portions 36a is sufficiently small, and the cross-sectional area of each of the bridging portions 36b is slightly larger than the cross-sectional area of the bridging portion 356a but sufficiently small. It can be easily broken. Bridge 3
6c is a first high-strength bridge having a large cross-sectional area. The bridging portion 36d is also a second high-strength bridging portion having a relatively large cross-sectional area. In FIG. 2, the first high-strength bridge 3
6c extends counterclockwise from one end located at an interval L1 in the counterclockwise direction (one in the circumferential direction) from the upper end of the axial breaking means 34, and the second high-strength bridging portion 36d is connected to the axial breaking means 36d. 34 extends clockwise from one end at an interval L2 in the clockwise direction (the other direction in the circumferential direction) from the upper end of 34. When attaching the container lid 2 to the mouth and neck of the container and when detaching the container lid 2 from the mouth and neck of the container, in order to ensure that the behavior described below is generated in the container lid 2 The cross-sectional area A1 of the first high-strength bridge portion 36c is 1.50 to 4.5.
A 0 mm ² mm, the cross-sectional area A2 of the second high strength bridging portion 36d is smaller (A2 <A1) 0.80 to 2.20 mm ² approximately than the cross-sectional area of the first high strength bridging portion 36c It is preferred that Further, the distances L1 and L2 are preferably about 1.00 to 3.00 mm.

An example of a procedure for manufacturing the container lid 2 as described above will be described as follows. First, the main body of the container lid 2 (that is, the portion excluding the sealing liner 24) is molded from an appropriate synthetic resin by compression molding or injection molding. In the molded container lid main body, the circumferential breaking means 8 is not yet formed, and the main portion 10 of the skirt wall 6 and the tamper-evident hem portion 12 at the portion of the circumferential breaking means 8 have the entire cross section. Connected in the area.
In addition, the thin curl 32 has not been curled yet, and FIG.
As shown by the two-dot chain line in FIG.

Thereafter, the following cutting step is performed to form the circumferential breaking means 8. As can be clearly understood with reference to FIG. 1, the inner peripheral surface of the skirt wall 6 also has an annular shoulder surface 38 which is oriented somewhat above and below the annular shoulder surface 26 described above. Protrusions 40a and 40b are formed below the annular shoulder surface 38 to extend slightly above the annular shoulder surface 26. A plurality of ridges 40a are arranged at equal intervals in the circumferential direction, and have substantially the same shape. The ridges 40b are also arranged at equal intervals in the circumferential direction, and have substantially the same shape. The number of the ridges 40a and the number of the ridges 40b are the same, and each of the ridges 40b is located in the middle of the adjacent ridge 40a. The ridge 40a (except for the ridge 40a located in the region of the first high-strength bridge 36c) defines the bridge 36a, and the ridge 40b (of the first high-strength bridge 36c). Excluding the ridge 40a located in the area)
Defines the bridging portion 36b. Therefore, the cross-sectional shape of the ridge 40a corresponds to the cross-sectional shape of the bridging portion 36a, and the cross-sectional shape of the ridge 40b corresponds to the cross-sectional shape of the bridging portion 36b. In the cutting step for forming the circumferential breaking means 8, first, leaving only the angle region where the first high-strength bridging portion 36c and the second high-strength bridging portion 36d are present,
The skirt wall 6 is gradually cut in the circumferential direction from its outer peripheral surface to its inner peripheral surface. The cutting blade used for such cutting is a ridge 40a.
And 40b do not substantially act on each other.
The radially outer portions of a and 40b can be partially cut, but the main portions of the ridges 40a and 40b are left without being cut, thus creating bridge portions 36a and 36b. Next, in the angle region where the first high-strength bridging portion 36c and the second high-strength bridging portion 36d exist, from the outer peripheral surface of the skirt wall 6 to a predetermined depth in the thickness direction of the skirt wall 6 (the illustrated embodiment). In this case, the skirt wall 6 is partially cut by the action of a cutting blade, thereby forming the first high-strength bridging portion 36c and the second high-strength bridging portion 36d. I do. As can be clearly understood by referring to FIG. 2, in the illustrated embodiment, one ridge 40a and one ridge 40b define a part of the first high-strength bridge 36c. ing. Next, a cutting blade extending in the axial direction is caused to act on the tamper-evident skirt portion 12, and is cut in the axial direction over the entire thickness direction up to substantially the lower end of the tamper-evident skirt portion 12. Forming the constituent slits.

After the above cutting step, a thin curl 34 is formed by applying a heating curl tool to the thin portion extending substantially vertically without being curled, so that the thin curl 34 is formed as shown by the solid line in FIG. . Next, the sealing liner is formed by the above-described molding process using a pressing tool, and thus the container lid 2 is completed.

FIG. 4 shows a state where the container lid 2 is attached to the mouth and neck portion 42 of the container as required. The mouth and neck portion 42 of the container, which can be formed from a suitable synthetic resin such as glass or polyethylene terephthalate, has a cylindrical shape as a whole, and has an outer thread 44 and a lower portion under the outer thread 44 on its outer peripheral surface. A positioned annular locking jaw 46 is formed. After filling the container with appropriate contents such as soft drinks, the container lid 2 is attached to the mouth and neck portion 42. At this time, the container lid 2 is fitted over the mouth and neck portion 42, and the container lid 2 is rotated in the closing rotation direction, that is, clockwise as viewed from above in FIG. The container cover 2 is screwed onto the male thread 44 of the mouth and neck 42, and the container lid 2 is lowered in accordance with the rotation. The flap piece 28 formed on the tamper-evident hem portion 12 of the container lid 2 is elastically deformed and passes through the locking jaw 46 of the mouth and neck portion 42, and then elastically recovers and engages. Locked to the jaw portion 46. When the flap piece 28 passes through the locking jaw 46, a radially outward force acts on the tamper-evident hem 12, and the tamper-evident hem 12 is broken in the axial direction due to the force. It is assumed that the slit constituting the means 34 is not expanded. However, in the container lid 2 constructed according to the present invention, a first high-strength bridging portion 36c (FIG. 2) exists on one side of the slit when viewed in the circumferential direction, and a second high-strength bridge exists on the other side. The presence of the entanglement 36d (FIG. 2) ensures that the undesired expansion of the slit is sufficiently prevented by the retaining action of the first high-strength bridge 36c and the second high-strength bridge 36d, and thus the container Breakage of the bridging portions 36a and 36b (FIG. 2) when the lid 2 is attached is sufficiently reliably prevented. The sealing liner 24 disposed on the inner surface of the top wall 4 of the container lid 2 is brought into close contact with the top surface of the mouth-neck portion 42, whereby the mouth-neck portion 42 is sealed.

When opening the mouth and neck portion 42 of the container, the container lid 2 is rotated in the opening rotation direction, that is, counterclockwise as viewed from above in FIG. As a result, the female thread 18 formed on the main part 10 of the skirt wall 6 of the container lid 2 is moved along the male thread 44 formed on the mouth and neck portion 42 of the container. Is raised with rotation. However, the tamper-evident hem portion 12 of the container lid 2 moves upward because the flap piece 28 formed on the inner peripheral surface thereof is locked to the locking jaw portion 46 of the mouth and neck portion 46. Is blocked. Therefore, the skirt wall 6
Bridging part 36 in the circumferential breaking means 8
a, 36b, 36c and 36d (FIG. 2) generate substantial stresses, which cause the bridging portions 36a and 36b to have a sufficiently small cross section to break, and also a second high strength bridging. The portion 36d is also broken. Furthermore, a thin curl 32 attached to the tamper-evident hem 12 is
It is broken along the extension of the slit (constituting the axial breaking means 34) formed in the tamper-evident foot 12. Such breakage of the thin curl 32 is sufficiently easily and reliably realized because the thickness is extremely thin. When the rupture is performed as described above, the skirt wall 6 is formed by the first high-strength bridging portion 36c remaining without being ruptured.
The tamper-evident hem portion 12 continued to be connected to the main portion 10 is deformed into a form extending in an arc shape from the portion where the first high-strength bridging portion 36c is present, and the locking jaw portion of the mouth and neck portion 42 is formed. The lock of the flap piece 28 with respect to 46 is released. After a while, tamper-evident hem 12
Of the container lid 2 is rotated with rotation, and thus the entire container lid 2 is detached from the mouth and neck portion 42. In the course of such opening operation, when the container liner 2 is raised slightly and the sealing liner 24 is separated from the top surface of the mouth-neck portion 42, the inside of the mouth-neck portion 42 becomes inside the mouth-neck portion 42. Between the top surface of the container lid 2 and the sealing liner 24, and through a notch 20 (FIG. 1) formed in the female thread 18 of the container lid 2.

If the first high-strength bridging portion 36d is accidentally broken during the opening operation as described above, the tamper-evident hem portion 12 is detached from the main portion 10 of the skirt wall 6, and Therefore, except for the tamper-evident hem 12 of the container lid 2, the tamper-evident hem 12 is left on the mouth and neck 42 while being removed from the mouth and neck 42. However, since the axial breaking means 34 formed on the tamper-evident skirt 12 is constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper-evident hem 12, a cutting knife or the like is required. If the thin curl 32 is not broken along the extension of the slit without breaking, the tamper-evident hem 12 that has been left sufficiently easily is detached from the mouth and neck 42. Can be.

FIG. 5 shows a modification of the first high-strength bridge. In the modified example illustrated in FIG. 5, in order to increase the cross-sectional area of the first high-strength bridging portion 136c and increase its strength, in the left end portion of the first high-strength bridging portion 136c in FIG. The tamper-evident foot portion 112 is not cut at all, and the first high-strength bridging portion 136c is located at the left end in FIG.
2 exists over the entire thickness direction from the outer peripheral surface to the inner peripheral surface.

FIG. 6 shows a modification of the first high-strength bridge and the second high-strength bridge. In the embodiment illustrated in FIG. 6, the tamper-evident foot 212 is not cut at all in the region of both the first high-strength bridging portion 236c and the second high-strength bridging portion 236d. Both the high-strength bridging portion 236c and the second high-strength bridging portion 236d exist in the entire thickness direction from the outer peripheral surface to the inner peripheral surface of the tamper-evident hem portion 112 in the entire circumferential direction. ing. On the other hand, the first high-strength bridging portion 236c
The circumferential length of the second high-strength bridging portion 236d is shorter than the circumferential length of the first high-strength bridging portion 36c and the second high-strength bridging portion 36d shown in FIG. Kai The one ridge 240b defines the first high-strength bridging portion 236c, and the ridge 240a located adjacent to and on the right side of the one ridge 240b has the first high-strength strength. Bridge 236
a is not specified, but a normal bridging portion 236a is specified.

FIG. 7 shows another modification of the first high-strength bridge and the second high-strength bridge. In the embodiment illustrated in FIG. 7, the first high-strength bridge 336c
Are separated from the upper end of the slit constituting the axial breaking means 334 without any space.
7, and the second high-strength bridging portion 336d is similarly spaced apart from the upper end of the slit forming the axial breaking means 334. However, the first high-strength bridging portion 336c and the second high-strength bridging portion 336d extend from the upper end of the slit constituting the axial breaking means 334 to the left in FIG. Are adjacent to each other.

FIG. 8 shows still another modification of the first high-strength bridge and the second high-strength bridge. The first high-strength bridging portion 436c of the embodiment shown in FIG. 8 is separated from the slit forming the axial breaking means 434 by a right One ridge 44
Ob defines the first high-strength bridging portion 436c, but the ridge 4 is located adjacent to and on the right side of the ridge 440b.
40a does not define the first high-strength bridging portion 436c but defines the normal bridging portion 436a, and the first high-strength bridging portion in the embodiment shown in FIGS. 36c. Further, the second high-strength bridging portion 436d illustrated in FIG. 8 is located leftward of the slit forming the axial breaking means 434 without leaving an interval from the upper end of the slit forming the axial breaking means 434. And one ridge 440a is connected to the second high-strength bridge 4
36d is different from the second high-strength bridging portion 36d in the embodiment shown in FIGS.

FIGS. 9 and 10 illustrate another preferred embodiment of a container lid constructed in accordance with the present invention. In the container lid 502 shown in FIG. 9 and FIG.
A sealing liner 524 is integrally formed on the inner surface of the cover 04. The sealing liner 524 includes an inner annular seal ridge 525 that enters the mouth and neck of the container and is closely contacted with the inner peripheral surface, and an outer annular seal ridge that is closely contacted with the upper surface and the outer peripheral surface of the mouth and neck of the container. 527. The locking means provided on the inner peripheral surface of the tamper-evident hem portion 512 includes an annular projecting piece 52 extending continuously in the circumferential direction.
8. The annular protruding piece 528 extends obliquely upward inward in the radial direction from a base edge 530 connected to the inner peripheral surface of the tamper-evident foot portion 512. The annular protruding piece 528 has slits 529 extending from the distal end to the vicinity of the base edge at intervals in the circumferential direction. When molding the container lid 502 from an appropriate synthetic resin, the annular projecting piece 528 extends downward inward in the radial direction as shown by a two-dot chain line in FIG. It is expedient to mold it into a form and to deform it into the state shown by the solid line after detaching it from the mold. An annular projecting piece 5 whose locking means extends continuously in the circumferential direction
In the embodiment consisting of 28, as will be understood by reference to FIG. 10, the annular projecting piece 528 is also aligned with the slit forming the axial breaking means 534 in the tamper-evident foot 512. It is preferable to form a slit extending continuously from the base edge to the tip. Such a slit in the annular protruding piece 528 is formed by the tamper-evidence hem 512
Can be conveniently formed by cutting the annular protruding piece 528 at the same time as forming the slit constituting the axial breaking means 534. FIG.
The configuration of the container lid 502 shown in FIG. 10 is substantially the same as that of the container lid 2 shown in FIGS. If desired, the circumferentially extending annular protruding piece 528 (or a plurality of circumferentially spaced flap pieces 28) may be replaced by a ratchet piece or the like well known to those skilled in the art. May be provided on the inner peripheral surface of the tamper-evident hem portion 512.

[0027]

In the container lid of the present invention, the axial breaking means provided on the tamper-edent hem is constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper-evidence hem. Therefore, when the bridging portion in the circumferential breaking means is broken except for one high-strength bridging portion when the container lid is detached from the mouth and neck of the container, the tamper-evident hem is inevitable. And the entire container lid is detached from the mouth and neck of the container. All bridges, including the high-strength bridge, are broken, so that even if the tamper-evident hem remains on the mouth and neck and the rest of the container lid is removed from the mouth and neck, Since the tamper-evident hem portion is formed with a slit extending continuously from the upper end to the substantially lower end, a complicated operation such as cutting the tamper-evidence hem portion with a cutting tool is required. In addition, the tamper-evident hem can be removed from the mouth and neck sufficiently easily. On the other hand, when attaching the container lid to the mouth and neck of the container, the holding action of the first and second high-strength bridging portions provided on both sides of the axial breaking means causes a tamper-evident hem portion. Is sufficiently suppressed from being expanded at the portion where the axial breaking means exists, and therefore, it is sufficiently ensured that at least some of the plurality of bridge portions in the circumferential breaking means are broken. Is prevented.

[Brief description of the drawings]

FIG. 1 is a front view, partially in section, of a preferred embodiment of a container lid constructed in accordance with the present invention.

FIG. 2 is a cross-sectional view taken along line AA in FIG.

FIG. 3 is a partial front view showing a modification of the axial breaking means.

FIG. 4 is a front view, partially in section, showing a state in which the container lid shown in FIG. 1 is attached to the mouth and neck of the container.

FIG. 5 is a partial cross-sectional view showing a modification of the first high-strength bridging portion.

FIG. 6 is a partial cross-sectional view showing a modified example of a first high-strength bridge portion and a second high-strength bridge portion.

FIG. 7 is a partial cross-sectional view showing another modified example of the first high-strength bridge portion and the second high-strength bridge portion.

FIG. 8 is a partial cross-sectional view showing still another modified example of the first high-strength bridge portion and the second high-strength bridge portion.

FIG. 9 is a front view, partially in section, of another preferred embodiment of a container lid constructed in accordance with the present invention.

FIG. 10 is a partial cross-sectional view taken along line BB in FIG. 10;

[Explanation of symbols]

 2: Container lid 4: Top wall 6: Skirt wall 8: Circumferential breaking means 10: Main part of skirt wall 12: Tamper evidence bottom 18: Female thread 28: Flap piece (locking means) 32: Thin curl 34: axial breaking means 36a: bridging portion 36b: bridging portion 36c: first high-strength bridging portion 36d: second high-strength bridging portion 42: mouth and neck portion of container 44: male thread 46: Locking jaw 112: tamper-evident hem 136c: first high-strength bridging portion 212: tamper-evident hem 236a: bridging portion 236c: first high-strength bridging portion 236d: second high-strength Bridge 334: Axial breaking means 336c: First high-strength bridging section 336d: Second high-strength bridging section 434: Axial breaking means 436a: Bridge section 436c: First high-strength bridging section 436d: Second high-strength bridge 50 : Lid 504: the top panel wall 512: tamper evident bottom portion 528: annular projection piece (engaging means) 534: axial breakage means

[Procedure amendment]

[Submission date] April 23, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction contents]

Thereafter, the following cutting step is performed to form the circumferential breaking means 8. As can be clearly understood with reference to FIG. 1, the inner peripheral surface of the skirt wall 6 also has an annular shoulder surface 38 which is oriented somewhat above and below the annular shoulder surface 26 described above. Protrusions 40a and 40b are formed below the annular shoulder surface 38 to extend slightly above the annular shoulder surface 26. A plurality of ridges 40a are arranged at equal intervals in the circumferential direction, and have substantially the same shape. The ridges 40b are also arranged at equal intervals in the circumferential direction, and have substantially the same shape. The number of the ridges 40a and the number of the ridges 40b are the same, and each of the ridges 40b is located in the middle of the adjacent ridge 40a. The ridge 40a (except for the ridge 40a located in the region of the first high-strength bridge 36c) defines the bridge 36a, and the ridge 40b (of the first high-strength bridge 36c). excluding protrusions 40 b located in the area)
Defines the bridging portion 36b. Therefore, the cross-sectional shape of the ridge 40a corresponds to the cross-sectional shape of the bridging portion 36a, and the cross-sectional shape of the ridge 40b corresponds to the cross-sectional shape of the bridging portion 36b. In the cutting step for forming the circumferential breaking means 8, first, leaving only the angle region where the first high-strength bridging portion 36c and the second high-strength bridging portion 36d are present,
The skirt wall 6 is gradually cut in the circumferential direction from its outer peripheral surface to its inner peripheral surface. The cutting blade used for such cutting is a ridge 40a.
And 40b do not substantially act on each other.
The radially outer portions of a and 40b can be partially cut, but the main portions of the ridges 40a and 40b are left without being cut, thus creating bridge portions 36a and 36b. Next, in the angle region where the first high-strength bridging portion 36c and the second high-strength bridging portion 36d exist, from the outer peripheral surface of the skirt wall 6 to a predetermined depth in the thickness direction of the skirt wall 6 (the illustrated embodiment). In this case, the skirt wall 6 is partially cut by the action of a cutting blade, thereby forming the first high-strength bridging portion 36c and the second high-strength bridging portion 36d. I do. As can be clearly understood by referring to FIG. 2, in the illustrated embodiment, one ridge 40a and one ridge 40b define a part of the first high-strength bridge 36c. ing. Next, a cutting blade extending in the axial direction is caused to act on the tamper-evident skirt portion 12, and is cut in the axial direction over the entire thickness direction up to substantially the lower end of the tamper-evident skirt portion 12. Forming the constituent slits.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 10 is a partial cross-sectional view taken along line BB in FIG. 9 ;

[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 10

Claims (6)

[Claims] 1. A synthetic material having tamper-evident characteristics, which is applied to a container having an external thread formed on an outer peripheral surface of a mouth and neck and a locking jaw located below the external thread. A resin container lid, comprising: a top wall and a skirt wall hanging down from the top wall,
The skirt wall is formed with a circumferential breaking means extending in a circumferential direction, and the skirt wall has a main portion above the circumferential breaking means and a tamper-evident hem below the circumferential breaking means. And a female thread cooperating with the male thread of the mouth-neck portion is formed on an inner peripheral surface of the main part of the skirt wall, and an inner peripheral face of the tamper evidence hem is formed. A locking means cooperating with the locking jaw of the mouth and neck portion is formed on the face, and the circumferential breaking means is disposed at a circumferential interval, and the tamper-evident hem is connected to the skirt wall. A plurality of bridging portions connected to the main portion, one of the bridging portions is a first high-strength bridging portion having a large cross-sectional area, and Is a synthetic resin container lid provided with axial breaking means, wherein said axial breaking means is And a plurality of bridging portions, each of which has a large cross-sectional area in addition to the first high-strength bridging portion. A second high-strength bridging portion, wherein the first high-strength bridging portion and the second high-strength bridging portion are disposed on both sides of the axial breaking means when viewed in the circumferential direction, The first high-strength bridge extends circumferentially from one end from or near an upper end of the axial breaking means, and the second high-strength bridge extends from an upper end of the axial breaking means or The female thread is attached to the mouth and neck by screwing the female screw to the male screw and locking the locking means to the locking jaw. ,
When the female thread and the male thread are released from the mouth and neck part by releasing the screw engagement, at least the first high-strength bridge part and the second high-strength bridge part are separated. One side is broken, A synthetic resin container lid characterized by the above-mentioned. 2. A cross-sectional area of the first high-strength bridging portion is larger than a cross-sectional area of the second high-strength bridging portion, and the union between the female screw and the male screw is released. When detached from the mouth and neck, the second high-strength bridging portion is broken, but the first high-strength bridging portion remains without being broken, and the tamper-evident hem portion 2. The web is deployed in a belt shape, the locking of the locking means to the locking jaw is released, and the entire container lid including the tamper-evident hem is detached from the mouth and neck.
The container lid made of the synthetic resin described in the above. 3. The cross-sectional area of the first high-strength bridge is 1.
A 50 to 4.50 mm ^2, the cross-sectional area of the second high strength bridging portion is 0.80 to 2.20 mm ^2, claim 2
The container lid made of the synthetic resin described in the above. 4. When viewed from the direction of rotation of the container lid when the female screw and the male screw are unscrewed and separated from the mouth and neck,
4. The composite of claim 2 or 3, wherein the first high strength bridge is located in front of the axial breaking means and the second high strength bridge is located behind the axial breaking means. Resin container lid. 5. The distance between the one end of the first high-strength bridge and the one end of the second high-strength bridge is 1.00 to 3.00 mm from the upper end of the axial breaking means. Located in
A synthetic resin container lid according to any one of claims 1 to 4. 6. A thin-walled curl extending from a lower end of the tamper-evident hem portion, and the slit constituting the axial breaking means extends only partially or completely into the thin-walled curl. A synthetic resin container lid according to any one of claims 1 to 5.