JPS60204468A - Vessel cover made of synthetic resin having pilfer-proof characteristic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a container lid made of synthetic resin, and more specifically, a container lid made of synthetic resin, and more specifically, a container lid having a male thread formed on the outer peripheral surface and a locking jaw portion located below the male thread. The present invention relates to a synthetic resin container lid having pilfer-proof properties for a container having a closed mouth and neck.

Prior Art Recently, synthetic resin container lids have been proposed and put into practical use in place of metal container lids as container lids with pilfer-proof properties for containers such as beverage bottles. It has become. Such a synthetic resin container lid includes a top wall and a cylindrical skirt wall that hangs down from the periphery of the top wall. A circumferential weakening line is formed on the skirt wall, and the skirt wall includes a plurality of slits extending in the local direction at intervals in the circumferential direction and a plurality of bridge portions existing between the slits. It is divided into a main portion above the circumferential weakening line and a pilfer-proof hem below the circumferential weakening line. A female thread is formed on the inner surface of the main portion, and a suitable type of locking means is formed on the inner surface of the pilfer-proof hem. Furthermore, an axial weakened line extending in the axial direction is formed in the pilfer-proof hem.

The above-mentioned continuous synthetic resin container lid is applied to a container having a neck portion in which a male thread and a locking jaw portion located below the male thread are formed on the outer peripheral surface. When closing the mouth and neck of a container with a container lid, the container lid is fitted onto the mouth and neck and rotated in a predetermined direction, that is, the closing direction, and the female thread on the container lid is screwed into the male thread on the mouth and neck. . In this way, as the container lid rotates in the closing direction relative to the mouth and neck and moves downward in the axial direction, the locking means of the container lid crosses over the engaging jaw part of the mouth and neck and engages with the lower surface of the container lid. I am forced to do it.

When opening the neck of the container, the container lid is rotated in the opposite direction to the closing direction, that is, in the opening direction. Thus,
Since the female thread of the container lid is moved along the male thread of the mouth and neck, the container lid rotates in the opening direction and moves upward in the axial direction. However, the pilfer-proof hem of the container lid cannot move upward in the axial direction because the locking means formed on its inner surface engages with the lower surface of the locking jaw of the mouth and neck. , therefore, considerable stress is generated in the axial line of weakness formed in the pilfer-proof hem, which causes the axial weakened line to break and the pilfer-proof hem to change from an endless ring shape to an edged band shape. The locking means is thus disengaged from the locking jaws. Additionally, the circumferential weakened line formed in the skirt wall is also broken due to the stress generated therein, leaving only a portion. After that,
The entire container lid is allowed to freely move upward in the axial direction, and the entire container lid is removed from the mouth and neck to open the mouth.

Therefore, it is important for the above-mentioned continuous synthetic resin container lid to ensure that the following two requirements are satisfied. First, when attaching the container lid to the mouth and neck of the container,
When the locking means of the container lid passes over the locking jaws of the neck and neck, considerable stress is generated in the axial weakened line formed in the pilfer-proof hem; must be maintained reliably without being broken. Secondly, however, it is necessary that the axial line of weakening formed in the pilfer-proof hem be sufficiently easily broken when the container lid is removed from the neck of the container. However, conventional synthetic resin container lids do not reliably satisfy the above two requirements, and when the container lid is attached to the mouth and neck of the container, the axial weakening line is broken, which is unacceptable. In many cases, the axial weakening line is not easily broken when the container lid is removed from the mouth and neck, making it extremely difficult to open the mouth and neck.

<Object of the Invention> The present invention was made in view of the above facts, and its main purpose is to provide an improved synthetic resin container lid that reliably satisfies the above two requirements.

<Summary of the Invention> According to the present invention, there is provided a pilfer-proof coating for a container having a neck portion in which a male thread and a locking jaw portion located below the male thread are formed on the outer peripheral surface. A container lid made of synthetic resin having a characteristic, comprising a top wall and a cylindrical skirt wall hanging from the periphery of the top wall, the skirt wall having a plurality of walls extending in the circumferential direction at intervals in the circumferential direction. A circumferential weakened line is formed consisting of a plurality of slits and a plurality of bridges existing between the slits, and the skirt wall has a main portion above the circumferential weakened line and a circumferential weakened line. The main part is divided into a lower pilfur-proof hem, and a female thread is formed on the inner surface of the main part to be screwed into the male thread of the mouth and neck. A locking means is formed on the inner surface of the portion to be engaged with the locking jaw portion of the mouth and neck portion, and further, an axial weakened line extending in the axial direction is formed on the pilfer-proof hem. In the container lid, the axial weakening is located in alignment with or close to the front end of the bridging portion O when viewed in the direction of rotation of the container lid when the container lid is attached to the mouth and neck. A container lid is provided, which is characterized in that the container lid extends downward in the axial direction from the upper end, inclining rearward as viewed in the container lid closing rotation direction.

DETAILED DESCRIPTION OF THE INVENTION A more detailed description will now be made with reference to the accompanying drawings, which illustrate preferred embodiments of container closures improved in accordance with the present invention.

Referring to FIG. 1, the illustrated container closure comprises a closure body, generally designated 2, which may be molded by compression or injection molding from any suitable synthetic resin material such as polyethylene or polypropylene. There is. This lid body 2
includes a circular top wall 4 and a cylindrical skirt wall 6 that hangs down from the periphery of the top wall 4.

An annular protrusion 8 is formed on the inner surface of the top wall 4, and a sealing liner 10 formed separately from the lid body 2 is disposed within the annular protrusion 8.

The sealing liner 10 can be formed directly at a predetermined position on the inner surface of the top wall 4 by well-known embossing after forming the lid body 2, or it can be formed into a predetermined shape completely separately from the lid body 2. It can be molded and then inserted into the inner surface of the top wall 4 of the lid body 2.

If desired, the sealing liner 10 can be formed integrally with the lid body 2.

The skirt wall 6 has a circumferential weakening line 1 extending in the circumferential direction.
2 is formed, and the skirt wall 6 is divided into a green part 14 above the circumferential weakening line 12 and a pilfer-proof hem 16 below the circumferential weakening line 12. The circumferential weakening line 12 itself is composed of a plurality of slits 18 extending in the circumferential direction at intervals in the circumferential direction, and a plurality of bridging parts 20 located between the slits 18. The proof skirt portion 16 is connected to the main portion 14 by a plurality of bridging portions 20 .

In the illustrated example, a specific one 20A of the plurality of bridging portions 20 in the circumferential weakened line 12 has a circumferential width that is larger than the circumferential width of the other bridging portions 20. ,
Therefore, the strength is greater than that of the other bridge portions 20. The circumferential weakening line 12 itself can be formed when the lid body 2 is molded, or by cutting the slit 18 after molding the lid body 2.

Advantageously, the outer surface of the main portion 14 of the skirt wall 6 is provided with an uneven or knurled shape 22 to prevent fingers from slipping thereon. A female thread 24 is formed on the inner surface of the main portion 14 . Locking means 26 are formed on the inner surface of the pilfer-proof hem 16, which is advantageously thinner than the main portion 14. The locking means 26 in the illustrated example is composed of a plurality of (eight in the illustrated case) protrusions arranged at intervals in the circumferential direction. If desired, a plurality of circumferentially spaced flap pieces projecting radially inwardly from the inner surface of the pilfer-proof hem 16; The locking means 26 can also be constructed from a continuously extending annular protrusion or the like.

The pilfer-proof hem 16 further has an axial weakening life 28 formed therein. Referring to FIG. 2 in conjunction with FIG. 1, in a container lid constructed in accordance with the present invention, the axial line of weakening 28 has its upper end connected to one of the bridges 20, preferably the The direction of the closing rotation of the wide bridging portion 20A as indicated by the arrow 30 of the container lid when the container lid is attached to the mouth and neck of the container as will be described later.
(i.e., clockwise as viewed from above in FIG. 1), and rearwardly from said upper end in the direction of said closing rotation as indicated by arrow 30; It is important that it extends axially downward at an angle of inclination α to the axis of the container lid. Preferably, the inclination angle α is between 20 and 70 degrees, particularly between 30 and 60 degrees. If the inclination angle α is too small, the axial weakening line 28 tends to break when the container lid is attached to the neck of the container, as will be described later, and the container The force required to break the axial weakened line 28 when the container lid is removed from the mouth and neck of the container tends to be relatively large. On the other hand, if the inclination angle α is excessively large, the length of the axial weakening line 28 will inevitably be excessively long, and as a result, as will be described later, the container lid can be removed from the mouth and neck of the container. It tends to be difficult to break the axially weakened life 28 over its entire length when detaching the axially weakened life 28.

The axial weakening line 28 itself may be formed of a so-called perforation, but it is more preferable that at least a large part thereof is formed of a so-called score formed by reducing the thickness of the material. In the illustrated embodiment, the axial line of weakness 28 is defined by a notch 32 located at its upper end and a score 34 extending from the lower end of the notch 32 to the lower end of the pilfer-proof hem 16. It is preferable that the notch 32 has a triangular shape that gradually becomes narrower toward the bottom. The illustrated notch 32 is in the shape of a right triangle, as clearly shown in FIG.
One side 32a extending substantially vertically is substantially aligned with the front end of the wide bridge portion 20A.

The open container lid described above is applied to a container having a neck 36, which is known per se and is in the open form shown in FIG. A male thread 38 and a locking jaw portion 40 located below the male thread 38 are formed on the outer peripheral surface of the mouth portion 36 .

When the container lid is attached to the mouth part 36 to close the mouth and neck part 36, the container lid is fitted to the mouth and neck part 36 and the container lid is moved in the closing direction, ff[I
In Fig. 3, rotate clockwise when viewed from above,
Thus, the female thread 24 on the container lid and the male thread 38 on the neck 36
Screw it together. In this way, the container lid is moved downward as it rotates, and at this time, the locking means 26 of the container lid is elastically displaced or deformed to engage the locking jaw portion 4o of the neck portion 36.
to overcome. When the female thread 24 is fully screwed into the male thread 38, the locking means 26 completely passes through the locking jaw 4° and is elastically restored, as shown in FIG.
It engages with the lower surface of the locking jaw portion 4o. Further, when the female thread 24 is fully screwed into the male thread 38, the sealing liner 10 of the container lid is pressed against the top surface of the neck part 36, as shown in FIG. securely sealed.

When the container lid is attached to the mouth and neck portion 36 of the container as described above, the container lid is rotated in the direction shown by the arrow 30 in FIG. When the locking means 26 passes through the locking jaw 40, a force acts to prevent the locking means 26 from moving downward. Due to the cooperation of the force transmitted to the pilfer-proof hem 16 through the bridging portion 20A and the force transmitted from the locking jaw 40 to the pilfer-proof hem 16 through the locking means 26, the weakened line 28 in the linear direction is A force acts in the direction indicated by arrow 42, ie a force which acts to prevent rupture of axial line of weakness 28.

In this way, breakage of the axial weakened line 28 is prevented with sufficient certainty.

When opening the neck portion 36, the container lid is rotated counterclockwise when viewed from above in FIG. 3, that is, in the opening rotation direction shown by arrow 44 in FIG. In this way, the female thread 24 of the container lid is moved along the male thread 38 of the neck portion 36, so that the container lid is moved upward as it rotates. However, the pilfer-proof hem 16 cannot move upward because the locking means 26 formed on its inner surface engages with the lower surface of the locking jaw 40 of the neck and neck portion 36. Therefore, considerable stress is generated in the bridging portion 2o of the circumferential weakening line 12, which causes the wide
All the bridge parts 20 other than the bridge part 2OA are broken (because the wide bridge part 20A has relatively high strength,
(maintained without being broken). At the same time, significant stress is generated in the axial weakened line 28 formed in the pilfer-proof hem 16, which causes the axial weakened life 28 to rupture.

Thus, in the event of rupture of the axial line of weakening 28, the container lid is rotated in the direction indicated by arrow 44 in FIG. Since upward movement is prevented, the forces transmitted to the pilfer-proof hem 16 through the wide bridging portion 20A and the forces transmitted from the locking jaws 40 to the pilfer-proof hem 16 through the locking means 26 cooperate. As a result, the axial line of weakening 28 is subjected to a force in the direction indicated by arrow 46, ie, a force in a direction effective to rupture the axial line of weakening 28. Thus, the axial line of weakness 2
8 is sufficiently easily broken from the top end to the bottom end.

When the axial weakening line 28 is broken, the pilfer-proof hem 16 is opened from an endless ring shape to an edged band shape.
The engagement between the locking means 26 formed on the inner surface of the pilfer-proof hem 16 and the locking jaws 40 of the neck and neck portion 36 is released. After that, the entire container lid can freely move upwards as it rotates, and thus the entire container lid is separated from the neck part 36 and the neck part 36 is opened.

In the illustrated embodiment, the pilfer-proof hem 16
Although only one axial weakened line 28 is formed on the pilfer-proof hem 16, if desired, a plurality of axial weakened lines 28 may be formed on the pilfer-proof hem 16 at appropriate intervals in the circumferential direction. can. In this case, when the opening portion 36 is opened, none of the bridging portions 20 in the circumferential weakened line 12 may be broken and maintained.

[Brief explanation of the drawing]

FIG. 1 is a side view, partially in section, of a specific example of a container lid improved according to the present invention. 2 is a partial side view showing an axial weakening line in the container lid of FIG. 1; FIG. FIG. 3 is a side view, partially in cross section, of the container lid shown in FIG. 1 attached to the mouth and neck of the container. 2...Lid body 4...Top wall 6...Skirt wall 12...Circumferential weakening line 14...Main part of skirt wall 16...Pilfur-proof hem 18...Slit 20 ... Bridge portion 20A... Wide bridge portion 24... Female thread 26... Locking means 28... Axial direction weakening line 32... Notch 34... Score 36...・Mouth and neck part 38... Male thread 40... Locking jaw part Fig. 1 9 Fig. 3

Claims (1)

[Scope of Claims] 1. Having pilfer-proof characteristics for a container having a mouth part in which a male thread and a locking jaw part located below the male thread are formed on the outer peripheral surface. A container lid made of synthetic resin, comprising a top wall and a cylindrical skirt wall hanging from the periphery of the top wall, the skirt wall having a plurality of slits extending in the circumferential direction at intervals in the circumferential direction. and a plurality of bridges existing between the slits, and the skirt wall has a main portion above the circumferential weakening line and a main portion below the circumferential weakening line. A female thread is formed on the inner surface of the main part to be screwed into the male thread of the mouth and neck part, and the inner surface of the pilfur-proof hem part is divided into a is formed with a locking means that engages with the locking jaw of the mouth and neck, and further has an axially weakened line extending in the axial direction formed in the hem of the Bilfer pull. In the container lid where the bridge is located; the axial weakening line extends from the upper end of the bridge section that is aligned with or close to the front end when viewed in the direction of rotation of the container lid when the container lid is attached to the mouth and neck. A container lid, characterized in that the container lid is inclined rearward and extends downward in the axial direction when viewed in the container lid closing rotation direction. 2. At least one of the skeleton bridge parts is a wide bridge part whose circumferential width is larger than the circumferential width of the other bridge parts, and the upper end of the axial direction weakening line is the wide bridge part. 2. A container lid according to claim 1, wherein the container lid is located in alignment with or close to the front end of the container lid when viewed in the direction of rotation of the container lid. 3. The axial weakening line is 2o to 70o with respect to the axis.
3. A container lid according to claim 1, wherein the container lid extends at an angle of inclination a of degrees. 4. The container lid according to claim 3, wherein the inclination angle α is 3o to 60 degrees. 5. A container lid according to any one of claims 1 to 4, wherein at least a large portion of the axial line of weakening is comprised of a score with reduced material thickness. 6. The container lid according to claim 5, wherein a notch is formed at the upper end of the axial weakening line. 7. The container lid according to claim 6, wherein the notch has a triangular shape whose width becomes gradually narrower toward the bottom. 8. The container lid according to claim 7, wherein the side edge of the notch located on the bridge portion side extends substantially vertically in the axial direction following the front end of the bridge portion.