JP2001206403A - Synthetic resin container cap having tamper-evident characteristic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure at a tamper-evident skirt. SOLUTION: The container cap 100 comprises a top wall 2 and a skirt wall 4, and the tamper-evident skirt is arranged at the lower end of the skirt wall 4. The tamper-evident skirt is formed of a plurality of temper-evident pieces 10 connected respectively with breakable bridging parts 12 to the lower end of the skirt wall 4. Each of the tamper-evident pieces 10 is in a arcuate shape and positioned so as to extend in the tangential direction at the outside in the radial direction of the skirt wall 4 with its top positioned at the upside thereof. A projected part 20 for engagement is provided at one end in the longitudinal direction of each of the tamper-evident pieces 10, while an engagement groove 30 is provided at the underside at the other end in the longitudinal direction of the tamper-evident piece, and a protuberance 40 for enagement is formed in the radial direction at the underside at the outer edge of the tamper-evident piece.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin container having a male screw and a locking jaw located below the male screw formed on the outer peripheral surface of an opening. More particularly, the present invention relates to a synthetic resin container lid having a tamper-evident characteristic (a characteristic in which traces remain when the container lid is operated to apply fraud).

[0002]

2. Description of the Related Art A container cover for a glass or synthetic resin container for accommodating a soft drink or the like, in which a male screw and a locking jaw located below the male screw are formed on the outer peripheral surface of an opening. For example, Japanese Patent Publication No. Sho 62-184
No. 20, a synthetic resin container lid having tamper-evident properties has been put to practical use.
The container lid of such a form includes a circular top wall and a skirt wall hanging from the top wall. A circumferential weakening line extending in the circumferential direction is formed on the skirt wall,
The skirt wall is divided into a main portion above the circumferential weakening line and a tamper-evident hem below the circumferential weakening line. The circumferential weakening line is constituted by a plurality of slits extending in the circumferential direction at intervals in the circumferential direction, and a plurality of bridging portions left between the slits,
The tamper-evident foot is connected to the main part via a plurality of bridges. On the inner peripheral surface of the main part of the skirt wall, a female screw is formed to engage with a male screw formed in the container opening. On the inner surface of the tamper-evident hem,
Locked means is provided which is locked by a locking jaw formed in the container opening. This locked means is constituted by a plurality of flap pieces formed at intervals in the circumferential direction.

The container lid is attached to the container opening by fitting the container lid into the container opening and rotating the container in the closing direction, and engaging the female screw of the container lid with the external thread of the container opening. Each of the flap pieces formed on the inner peripheral surface of the tamper-evident hem of the container lid elastically rides over the locking jaw of the container opening and is locked to the lower side. When the container lid is attached to the container opening, the sealing means provided on the inner surface of the top wall of the container lid is brought into close contact with the upper end of the container opening, and the container opening is sealed. To open the container opening, the container is rotated in the opening direction. Due to this rotation, the female screw of the container lid is moved along the male screw of the opening and the engagement between them is released, so that the container lid is raised in accordance with the rotation in the opening direction. Each of the flap pieces formed on the tamper-evidence hem is locked to the locking jaw of the container opening, so that the tamper-evidence hem is prevented from rising, resulting in circumferential weakening Stress is created in the line and all or at least most of the bridge breaks. After this, the tamper-evident hem is left at the container opening, and the other parts of the container lid, or the entire container lid including the tamper-evident hem is raised in accordance with the rotation in the opening direction. It is separated from the opening.

As described above, the conventional synthetic resin container lid having tamper-evident characteristics is, for example, compression-molded by cooperation of an upper die provided with a core portion and a lower die provided with a concave portion. Formed by That is, after a predetermined amount of the synthetic resin material is injected into the concave portion of the lower die, the lower die is raised in a direction approaching the upper die, and a molding space is formed between the concave portion of the lower die and the core portion of the upper die. It is formed. The synthetic resin material injected into the concave portion of the lower mold is filled in the molding space, whereby the container lid is molded. The lower mold is lowered for release,
It is released from the outside of the container lid. Next, the core portion of the upper mold is forcibly pulled out from the inside of the container lid to be completely released from the upper mold, and the container lid is detached from the upper mold.

[0005]

As described above, when the conventional mold release of the synthetic resin container lid having the tamper-evident property is performed in the axially downward direction after the compression molding, the forcible removal is performed. You. This forced removal is a part that becomes an undercut at the time of molding the container lid, for example, a female screw formed on the inner peripheral surface of the main portion of the skirt wall, a plurality of formed on the inner peripheral surface of the tamper evidence hem. This is performed due to the presence of flap pieces and the like. When the container lid of the above-mentioned form is formed from a relatively soft synthetic resin such as polyethylene, for example, it is possible to relatively easily perform the forcible removal during molding. However,
In the container lid of the above-described embodiment, the structure of the inner peripheral surface of the tamper-evident hem is significantly complicated due to the presence of the flap pieces and the like. As a result, the structure of the mold for molding is complicated, so that the production cost of the mold is high and the production speed is reduced. Further, in order to simplify the configuration of the inner peripheral surface of the tamper-evident hem, a container lid in which a locked means formed on the inner peripheral surface of the tamper-evident hem is formed from a locked projection is also proposed. However, in consideration of the releasability, the angle between the inner peripheral surface of the tamper-evident hem and the locked side of the locked projection cannot be formed to be an acute angle. As a result, in this container lid,
It becomes difficult to ensure the engagement between the tamper-evident hem and the locking jaw of the container opening, and a problem remains in practical use.

On the other hand, when the container lid of the above-described embodiment is formed of a relatively hard synthetic resin such as polyethylene terephthalate (PET), the underside of the tamper-evident bottom part has a complicated shape. Since it becomes a cut portion, it is extremely difficult to forcibly remove the container. If the forcible removal is forcibly performed, there is a high possibility that the container lid is damaged or broken. As a result, it is considered that it is impossible to mold the container lid of the above-mentioned form with a relatively hard synthetic resin. In the case of a container lid having no tamper-evident hem portion, the female screw formed on the inner peripheral surface of the main portion of the skirt wall becomes an undercut portion. Even if the container lid is made of a relatively hard synthetic resin, the molding is possible.

In recent years, containers for soft drinks and the like
Although PET bottles, so-called PET bottles, are widely used in practice, the above-mentioned container lid attached to the PET bottle cannot be made of PET for the above-mentioned molding reasons. Is used. Therefore, when the container lid is of a form that can be opened with the tamper-evident hem remaining at the container opening, and when the container is made of PET, the tamper-evident remaining at the container opening is used. Hem is PE
Since it is made of a synthetic resin other than T, in order to perform the above-mentioned separate collection, it is necessary to separate the tamper-evident hem from the container by breaking the hem of the tamper-evidence using a knife or the like. The work of separate collection (collection by material) becomes extremely complicated. This fact is extremely inconvenient from the viewpoint of separate collection, and improvement is demanded. On the other hand, a container lid of a form in which the tamper-evident hem is broken off in the axial direction at the same time as opening and removed from the container integrally with the container lid has been proposed, but when the tamper-evident hem remains in the container opening. For that reason, the function has not been able to be surely performed yet, and improvement is demanded.

[0008] The present invention has been made based on the above fact, and an object of the present invention is to make it possible to simplify the configuration of the tamper-evident hem portion, and as a result, to simplify the structure of a mold for molding. It is an object of the present invention to provide a synthetic resin container lid with a novel tamper-evident property, which enables the production cost of the mold to be reduced and the production speed to be increased.

Another object of the present invention is to make it easy to forcibly remove the tamper-evident foot from the skirt of the tamper-evident body even when using a relatively hard synthetic resin such as PET. It is an object of the present invention to provide a synthetic resin container lid with novel tamper-evident properties.

Another object of the present invention is to provide a container lid made of a synthetic resin having a novel tamper-evident property, which makes it possible to remarkably facilitate the separate collection operation even when applied to a so-called PET bottle. It is to be.

Other objects and features of the present invention will become apparent from the following description of embodiments of a synthetic resin container lid having tamper-evident properties according to the present invention with reference to the accompanying drawings. There will be.

[0012]

According to one aspect of the present invention, a tamper evidence is applied to a container having an external thread formed on an outer peripheral surface of an opening and a locking jaw located below the external thread. A synthetic resin container lid having characteristics, comprising a top wall and a skirt wall hanging down from the top wall, a female screw engaging with the male screw is formed on an inner peripheral surface of the skirt wall, and a skirt wall is formed. In a synthetic resin container lid having tamper-evident characteristics, in which a tamper-evidence hem is disposed at a lower end, the tamper-evidence hem has a plurality of breakable bridges spaced apart in a circumferential direction. A plurality of tamper-evident pieces having substantially the same configuration are connected to the lower end of the skirt wall via the entanglement, and each of the tamper-evident pieces is formed to have a substantially arc shape. With In the shape state, the skirt wall is positioned so as to extend tangentially outside in the radial direction and has a top portion on the upper surface side, and each of the tamper evidence pieces has a locked projection at one longitudinal end thereof. A locking groove is formed on the lower surface of the other end in the longitudinal direction, and a locked projection is formed on the lower surface of the outer edge in the radial direction. Each of the tamper evidence pieces is forced downward in the axial direction to simultaneously bridge the bridge. When swiveled around each of the entangled portions, each locked projection of the tamper-evident piece is locked in the opposite locking groove, and the tamper-evident hem is substantially below the lower end of the skirt wall. The tamper-evident piece is formed so as to be continuous in the upper circumferential direction, and is locked to the locking jaw of the container opening at the radially inner side of the tamper-evident hem by each of the locked projections. A locked ridge is formed. Plastic container closure having a tamper evident properties which is characterized in, is provided.

According to another aspect of the present invention, a composite having tamper-evident characteristics, which is applied to a container having a male screw and a locking jaw located below the male screw formed on the outer peripheral surface of the opening. A lid made of a resin, comprising a top wall and a skirt wall hanging down from the top wall, a female screw engaging with the male screw is formed on an inner peripheral surface of the skirt wall, and a tamper shrimp is formed at a lower end of the skirt wall. In the synthetic resin container lid having tamper-evident characteristics, in which the dent hem is disposed, the tamper-evident hem is spaced apart in the circumferential direction, via a plurality of breakable bridging portions. A plurality of tamper-evident pieces having substantially the same configuration are connected to the lower end of the skirt wall, and each of the tamper-evident pieces is formed so as to have a substantially arc shape and is in a state at the time of molding. To The skirt wall is positioned so that it extends tangentially outside the skirt wall in the tangential direction and has an apex on the upper surface side. Each of the tamper evidence pieces has a locked projection at one longitudinal end and a longitudinal other end. A locking groove on the lower surface of the portion, and a locked projection formed on the lower surface of the radially outer edge, respectively, a synthetic resin container lid having tamper-evident characteristics, Is provided.
In each of the container lids according to one aspect and another aspect of the present invention, the locked projection formed at one end of each of the tamper-evident pieces has a base end extending at a constant width and a base end extending from the base end. A leading end portion, the leading end portion protruding on both sides in the width direction, forming a locked portion having a pair of locked steps, and a locking groove formed at the other end of each of the tamper evidence pieces. Are a pair of guides extending at a predetermined depth from the other end toward the one end on the lower surface of the tamper-evident piece and having a width smaller than the maximum width of the locked portion of the corresponding locked projection. A receiving portion having a pair of receiving surfaces and a pair of receiving steps each having a width wider than the introducing portion and having a width capable of receiving the locked step of the locked projection. Each locked step of the locked projection is locked to the locking step of the corresponding locking groove. By being tamper evident bottom portion which is continuous in substantially the circumferential direction is formed, it is preferable. In the container lid, in a state at the time of molding,
Each of the introduction surfaces in the introduction portion of the locking groove formed in each of the tamper evidence pieces, and the base end portion of the locked projection and both side surfaces in the locked portion are separated from each other as going upward. Formed so as to be gently inclined, each locked step of the locked projection is locked to the locking step of the corresponding locking groove, forming a tamper-evident hem substantially continuous in the circumferential direction. In this state, it is preferable that both side surfaces of the base end portion of the locked projection are engaged with the corresponding introduction surface of the introduction portion of the engagement groove so as to be substantially aligned. In the container lid, the synthetic resin is preferably polyethylene terephthalate.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a synthetic resin container lid having tamper-evident characteristics constituted according to the present invention will be described below in detail with reference to the accompanying drawings.

Referring to FIG. 1 to FIG.
Is a circular top wall 2 that covers the top of the opening (container opening) 202 of the container 200 (see FIGS. 9 and 10).
And a substantially cylindrical skirt wall 4 hanging down from the periphery of the top wall 2. On the inner peripheral surface of the skirt wall 4, a male screw 20 formed on the outer peripheral surface of the container opening 202 is provided.
A female screw 5 to be engaged with 4 is formed. At the upper end of the inner peripheral surface of the skirt wall 4, a small diameter portion 6 slightly smaller than the inner diameter of the female screw 5 is formed. A sealing liner 7 formed separately from the container lid 100 is provided in close contact with the inner peripheral surface of the small diameter portion 6 and the inner peripheral surface of the top wall 4. The container lid 100 can be integrally formed from a relatively soft synthetic resin such as polyethylene or polypropylene, or a relatively hard synthetic resin such as polyethylene terephthalate (PET). , Made of polyethylene, which is a relatively soft synthetic resin. In the following description of the present specification, “upper” in terms such as “upper”, “upper”, “upper”,... Means the side where the top wall 2 exists in the axial direction of the container lid 100, "Lower" in terms such as lower, lower, lower end, etc., in the axial direction of the container lid 100,
It means the side opposite to the top wall 2. The term “axis” or “axis” means the axis or axis of the container lid 100 which is common to the axis or axis of the top wall 2 and the skirt wall 4. Furthermore, the “tangential direction” means the tangential direction of the skirt wall 4.

At the lower end, which is the open end of the skirt wall 4, a plurality of, in the embodiment, six tamper-evident pieces 10, each having a substantially identical configuration, are provided with a plurality, respectively, in the embodiment. They are connected via breakable thin bridging portions 12. Tamper Evidence Piece 1
Each of the zeros constitutes a tamper-evident hem disposed at the lower end of the skirt wall 4. As will be described later, the tamper-evident skirt portion is deformed so as to be substantially continuous in the circumferential direction. However, in the state at the time of molding, the tamper-evident hem portion is discontinuous in the circumferential direction as illustrated. Make the hem. Each of the tamper-evident pieces 10 is disposed at substantially equal intervals in the circumferential direction, and each of the bridging portions 12 connecting each of the tamper-evident pieces 10 to the lower end of the skirt wall 4 is provided with a respective tamper-evident piece. The dent pieces 10 are arranged at intervals in the circumferential direction. Since the configuration of each of the tamper-evidence pieces 10 and each of the bridging portions 12 and the form of attachment to the lower end of the skirt wall 4 are substantially the same, one representative tamper-evidence piece will be described below. 10 will be described.

The tamper-evident piece 10 is disposed so as to extend tangentially at a position near the radially outer end of the lower end of the skirt wall 4. The tamper-evident piece 10 has both widthwise side surfaces extending in a tangential direction parallel to each other, and one end surface and the other end surface in the longitudinal direction extending perpendicular to the both side surfaces, and is shown in FIG. When viewed in the axial direction, the profile is an elongated band shape or an elongated rectangular shape that extends linearly in the tangential direction, and has an arc shape centered downward in the axial direction when viewed from the radial outside of the skirt wall 4. (See FIG. 4). Therefore, an arc-shaped apex exists at the center in the longitudinal direction on the upper surface side of the tamper-evident piece 10. The tamper-evident piece 10 is also positioned such that, when viewed tangentially, it extends further radially outwardly from near the radially outer side of the skirt wall 4 and in a direction substantially orthogonal to the axis, and the top of its top surface is Are positioned on or near a plane that is orthogonal to the axis and substantially coincides with a plane that coincides with the lower end surface of the skirt wall 4 (see FIG. 4). The bridging portions 12 are arranged at intervals in the longitudinal direction of the tamper-evident piece 10, and the bridging portions 12
Is integrally connected to a radially outer end of the lower end of the skirt wall 4, and the other end is integrally connected to an upper end of the widthwise inner surface of the tamper-evident piece 10. Each of the bridging portions 12 extends downwardly and radially outward from the radially outer end at the lower end of the skirt wall 4 (see FIG. 4). Bridge 12
Each also have a longitudinal center of the tamper-evident piece 10 and a container lid 10 viewed axially as shown in FIG.
They are arranged at equal intervals with a virtual straight line L connecting the zero axis O interposed therebetween, and are formed so as to extend in parallel with the straight line.

Referring mainly to FIGS. 4 to 6, a locked projection 20 is formed on one end in the longitudinal direction of the tamper-evident piece 10, and a locking groove 30 is formed on the lower surface of the other end in the longitudinal direction. The lower jaw 206 of the container 200 (see FIG.
(See FIG. 3) is formed.
The locked projection 20 is formed to protrude in the longitudinal direction from the axial lower end of one end surface defining one longitudinal end of the tamper evidence piece 10. The locked projection 20 is formed so as to have a certain thickness in the axial direction as a whole, and its lower surface is positioned on the same arc surface as the lower surface of the tamper-evident piece 10 (the lower surface excluding a locked projection 40 described later). Have been. The locked projection 20 has a base end 21 extending at a constant width.
And a distal end following the proximal end 21. Base 2
The lengths of the two side surfaces 21a are equally defined. The distal end portion of the locked projection 20 forms a locked portion 22 protruding to both sides in the width direction with respect to the base end portion 21. Locked part 22
At the boundary with the base end 21, a pair of locked steps 23 are formed from both sides in the width direction of the base end 21, each having the same length and extending substantially at right angles. The distal end of the locked portion 22 is formed to be orthogonal to both sides in the width direction of the base end portion 21. In addition, it defines both sides of the locked portion 22,
Each of the widthwise side surfaces 22a between both ends in the width direction of the locked stepped portion 23 and the tip end approach each other in the width direction from both ends in the widthwise direction of the locked stepped portion 23 toward the tip end. (See FIG. 6).

The locking groove 30 is provided with the tamper-evident piece 10.
Is formed so as to extend with a certain depth as a whole from the other end in the longitudinal direction to one end on the lower surface of the. This depth is substantially the same as or slightly larger than the thickness of the locked projection 20. The locking groove 30 includes an introduction portion 31 having a pair of introduction surfaces 31a that extend in parallel to the one end at a fixed distance from the other end and extend by the same length, and an introduction portion 31.
The receiving part 32 formed on the one end side and the receiving part 3
2 and a tip portion 33 formed on the one end side. The distal end portion 33 is positioned between the receiving portion 32 and the introduction portion 31.
And a side surface 33a formed on the extension of the introduction portion 31 and present on each extension of the introduction surface 31a of the introduction portion 31.
And a tip surface 33b extending orthogonally to each of them. The receiving portion 32 includes a pair of receiving surfaces 32a having a width larger than the width of the introducing portion 31 defined by the respective intervals of the introducing surfaces 31a. Each of the receiving surfaces 32a is equidistantly spaced radially outside of each of the virtual lines connecting the introduction surfaces 31a of the introduction portion 31 and the corresponding side surfaces 33a of the distal end portion 33, respectively. Are formed so as to extend in parallel with each other. Receiving department 3
2, a pair of locking steps 34 is formed at the boundary with the introduction section 31. Each of the locking step portions 34 is the same between the one end of the introduction surface 31a of the introduction portion 31 and the corresponding one end of the reception surface 32a of the reception portion 32 in the width direction orthogonal to the respective ends. It is provided to extend in length.
The width of the introduction portion 31 is formed to be smaller than the maximum width of the locked portion 22 of the locked projection 20 (the maximum width defined by both ends in the width direction of the locked step portion 23). The width of the receiving portion 32 defined by each interval of the receiving surfaces 32 a is formed to be large enough to receive the locked step portion 23 of the locked portion 22 of the locked projection 20. In the illustrated embodiment, the width of the receiving portion 32 is formed slightly larger than the maximum width of the locked portion 22 of the locked projection 20.

The locked protrusion 40 formed on the lower surface of the outer edge of the tamper evidence piece 10 in the radial direction (width direction)
A width-direction outer surface extending downwardly from the width-direction outer upper end of the tamper-evidence piece 10 with a gentle curved surface toward the axis; and a predetermined width than the width-direction outer end surface, extending axially downward from the width-direction inner lower surface. It is formed from an inner surface in the width direction to be protruded, and a round surface connecting the lower ends of the surfaces.
Tamper-evident fragment 1 configured as described above
0 has a rectangular shape elongated in the width direction except for a portion where the locked projection 40 is formed, and is substantially the same as a whole from one end to the other end in the longitudinal direction. Since the locking groove 30 is formed on the lower surface of the portion, only the region of the other end where the locking groove 30 is formed has a different cross-sectional shape.

When the container lid 100 is formed (see FIG. 4), the locking grooves 30 formed in each of the tamper-evident pieces 10 are not clearly shown in FIGS.
Each of the introduction surfaces 31a in the introduction portion 31 and each of the both side surfaces 21a of the base end portion 21 of the locked projection 20 and the both side surfaces 22a in the locked portion 22 are gently moved away from each other upward. It is preferable to be formed so as to be inclined (formed so as to form an inclined surface). As will be further described below, each of the tamper-evident pieces 10 is forced downward in the axial direction and simultaneously pivoted about each of the bridging portions 12, and the locked projections 20 on each of the tamper-evident pieces 10 are rotated. A state in which each of the locked step portions 23 is locked by the locking step portion 34 of the corresponding locking groove 30 to form a tamper-evident hem portion 50 (see FIG. 7) substantially continuous in the circumferential direction. In the above, both side surfaces 21 a of the base end portion 21 of the locked projection 20 are engaged with the corresponding introduction surfaces 31 a of the introduction portion 31 of the engagement groove 30 substantially in alignment. As described above, each of the introduction surfaces 31a of the introduction portions 31 of the engagement grooves 30 formed in each of the tamper evidence pieces 10 and each of the both side surfaces 21a of the base end portion 21 of the engagement projection 20 and the The side surfaces 22a of the locking portion 22 are formed as inclined surfaces that are gently inclined in a direction away from each other as going upward, and the degree of inclination (inclination angle) of these inclined surfaces is determined at the time of molding. It is preferable that the width is set to such an extent that the die can be cut downward in the axial direction. Since the illustrated container lid 100 is made of polyethylene which is a relatively soft synthetic resin, the inclination angle of the inclined surface from which the mold can be cut can be made relatively large. On the other hand, when the container lid 100 is formed of PET, which is a relatively hard synthetic resin, the inclination angle of the inclined surface from which the mold can be cut is set to polyethylene, which is a relatively soft synthetic resin as in the above embodiment. It is significantly smaller than when formed from the like. However, as described above, the configuration of the tamper-evident pieces 10 is significantly simpler, and thus each of the tamper-evident pieces 10 can be a circumferentially continuous tamper-evident foot 50 as described below. It is possible to form, on each of the above surfaces, an inclined surface that is gently inclined to the extent that it can be die-cut. In the above-described embodiment, the widthwise outer surface of the tamper-evident piece 10 and the widthwise outer surface of the locked projection 40 following the outer surface are formed so as to extend downward in the axial direction with a gentle curved surface in the axial direction. It is easy to remove the mold regardless of the material.

At least one location at the lower end of the skirt wall 4,
In this embodiment, two ratchet pawls 4a are formed (see FIG. 7). Each of the ratchet pawls 4a is formed substantially diametrically opposite to each other with the axis O interposed therebetween. Each of the ratchet pawls 4a is composed of an end surface on the plugging direction side extending parallel to the axial direction, and an inclined surface inclined from the tip of the end surface toward the opening direction. Also, a ratchet claw 10a is formed on at least one tamper-evident piece 10, in this embodiment, on the radially inner side face of each of the two tamper-evident pieces 10 corresponding to each of the ratchet claws 4a. (See FIG. 1). Each of the ratchet pawls 10a is composed of an end surface on the opening direction that extends at right angles from the corresponding side surface toward the skirt wall 4, and an inclined surface that is inclined from the tip of the end surface in the closing direction. Each of the ratchet pawls 4a and 10a may use a known configuration.

Referring to FIG. 7 and FIG. 8, the tamper-evident piece 1 of the container lid 100 formed as described above
Each of the zeros can force them axially downward, causing each of the tamper-evident pieces 10 to simultaneously pivot radially inward approximately 90 degrees about each of the bridges 12 as pivot points. . This forcing operation is performed, for example, by fitting the inside of the skirt wall 4 of the container lid 100 before disposing the sealing liner 7 to a substantially cylindrical receiving jig (not shown) and supporting the same. This can be easily achieved by moving the inner peripheral surface of the cylindrical forcing jig (not shown) axially downward along the outer peripheral surface of the skirt wall 4. As one embodiment of the receiving jig, a receiving jig including a plurality of receiving members arranged in a substantially cylindrical shape at intervals in a circumferential direction can be cited. Each of the receiving members in the receiving jig of this form is elongated in the axial direction and has an arc-shaped cross section, and moves to a forced working position and a non-working position moved radially inward from the forced working position. It can be configured freely. The corner at the upper end of each of the receiving members may be formed in a round shape or an appropriate curved surface, or may be formed so as to be inclined upward and inward in the radial direction so that the container lid 100 can be smoothly placed. It is preferable to be fitted to the surface. A container 200 is provided on the radially outer surface of each of the receiving members.
It is preferable to form a ridge (not shown) having a shape matching the locked jaw 206 at a position matching the position where the locked jaw 206 (see FIG. 10) exists. On the other hand, the cylindrical forcing jig is provided with a container lid 10.
The skirt wall 4 preferably has an inner diameter slightly larger than the maximum outer diameter. Then, each of the tamper-evident pieces 10 smoothly turns around each of the bridging portions 12 so as not to be damaged when being pressed against the upper surface of each of the tamper-evident pieces 10 and forced downward in the axial direction. In order to allow the forcing jig to be formed, the circular lower end surface of the forcing jig may have a round shape or an appropriate curved surface, or the inner peripheral surface of the lower end portion may be formed in a flared shape in which the inner diameter is increased downward. preferable.

The inside of the skirt wall 4 of the container lid 100 is fitted and supported on the receiving jig (each of the receiving members is positioned at the forcible operation position), and then the cylindrical forcing jig of the forcing jig is formed. By moving the inner peripheral surface axially downward along the outer peripheral surface of the skirt wall 4, each of the tamper-evident pieces 10 is forced downward in the axial direction, and each of them is simultaneously pivoted about each of the bridging portions 12. When turned,
Each locked projection 20 of the tamper-evident piece 10 is locked in the locking groove 30 opposed thereto. The tamper-evident hem that is discontinuous in the circumferential direction in the state at the time of molding,
The lower part of the skirt wall 4 is deformed into a tamper-evident hem 50 substantially continuous in the circumferential direction. The operation in which each of the locked projections 20 is locked in the opposite locking groove 30 is automatically performed in a process in which each of the tamper evidence pieces 10 is simultaneously turned around each of the bridging portions 12 as the turning center. Is done.

More specifically, as each of the tamper-evident pieces 10 is simultaneously swung about each of the bridging portions 12 as the center of rotation, the respective tamper-evident pieces 10 are circumferentially opposed to each other. Since the one end face and the other end face in the longitudinal direction approach each other in the circumferential direction, the locked projections 20 and the locking grooves 30 facing each other in the circumferential direction gradually approach in the circumferential direction. The distal end of the locked portion 22 is relatively inserted into the introduction portion 31 of the locking groove 30.
The inclined side surfaces 22a of the locked portion 22 smoothly guide the insertion. By further turning, the distal end of the locked portion 22 is relatively moved in the circumferential direction along the introduction portion 31,
Then, it is fitted into the receiving portion 32 of the locking groove 30. Each inner surface of the tamper-evident piece 10 is pressed against the radially outer surface of the ridge portion of each of the receiving members positioned at the forced operation position, thereby turning each of the tamper-evident pieces 10. Is completed, the locked step portion 23 of the locked portion 22 of the locked projection 20 is moved to the locking groove 30.
Locking step 3 of the receiving part 32 relatively beyond the introduction part 31
4 (see FIG. 8), and the tamper-evident piece 10
Are locked in the direction in which they are separated in the circumferential direction. Each of the tamper-evident pieces 10 is formed into a substantially continuous ring shape in the circumferential direction to form a tamper-evident foot 50. Further, as described above, in the state at the time of molding the container lid 100 (see FIG. 4), each of the introduction surfaces 31a of the introduction portions 31 of the locking grooves 30 formed in each of the tamper-evident pieces 10 is in contact with each other. , Locked projection 2
0 and each of the side surfaces 21 a of the base end portion 21 and the locked portion 22.
Are formed so as to be gently inclined in a direction away from each other as going upward.
In addition, in the state where the tamper-evident hem portion 50 is formed as described above, both side surfaces 21a of the base end portion 21 of the locked projection 20 correspond to the corresponding introduction surfaces 31a of the introduction portion 31 of the locking groove 30. Are substantially aligned with each other. As a result, even if the tamper-evident hem portion 50 receives a force directed outward in the radial direction, the introduction portion 31
Locked projection 2 of each of the inclined introduction surfaces 31a at
The corresponding inclined sides 21 at the base end 21 of the zero
Since the relative movement in the radial direction with respect to a is prevented, the tamper-evident piece 10 is prevented from being unlocked.

At the same time as the formation of the tamper-evident foot 50, each of the locked projections 40 allows the container opening 20 to be opened.
The locked ridge 60 locked to the second locking jaw 206 is formed. The locked ridge 60 is formed to extend substantially annularly. By performing the above-described forced operation, the container lid 100 having the tamper-evident hem portion 50, that is, the container lid 100 having the tamper-evident characteristic is formed. Each end face of the ratchet pawl 4a formed at the lower end of the skirt wall 4 on the closing direction side, and the ratchet pawl 10 formed on each side face of the tamper evidence piece 10
The respective end faces on the opening direction side of a are positioned so as to face each other at intervals in the circumferential direction (see FIG. 7). As can be easily understood from the above description, the radius of the arc of the lower surface in the axial direction of each tamper-evident piece 10 in the state at the time of molding is determined by the inner circumference of the tamper-evident foot 50 formed after the forcing operation. It is formed substantially the same as the radius of the surface. Further, the circumferential length of each of the tamper-evident pieces 10 in the state at the time of molding is formed to be approximately 円 of the circle formed by the tamper-evident foot 50.

After the tamper-evident hem portion 50 is formed on the container lid 100 by performing the above-mentioned forced operation,
The forcing jig is moved axially upward along the outer peripheral surface of the skirt wall 4 and detached above the container lid 100. Next, each of the receiving members constituting the receiving jig is moved radially inward from the forced operation position to be positioned at the non-operation position. The circumferential spacing between each of the receiving members is defined to at least allow the movement. Thereby, since the outer peripheral surface of each of the receiving members is positioned inside the inner peripheral surface of the locked ridge 60 formed inside the tamper-evident hem portion 50, the container lid 100 is separated from each of the receiving members. It can be easily removed in the axial direction. The tamper-evident hem 50 is added to the container lid 100 as described above.
Is formed, the sealing liner 7 is formed in the container lid 100 using, for example, compression molding. The forcing operation can be performed after the sealing liner 7 is provided. In this case, however, it is necessary to prevent the receiving jig from contacting the sealing portion of the sealing liner 7 (as described above). This can be achieved by forming a round shape or forming an inclined surface at a corner at the upper end of each of the receiving members.)

In the above embodiment, the jig for forming the tamper-evident hem 50 on the container lid 100 by forcing each of the tamper-evident pieces 10 downward in the axial direction is substantially spaced apart in the circumferential direction. A jig combined with a receiving jig composed of a plurality of receiving members arranged to form an upper cylindrical shape and a forcing jig having a cylindrical shape is used, but is of course limited to these configurations. For example, a receiving jig having a cylindrical shape,
Other embodiments use a jig that is combined with a forcing jig of substantially the same form as described above. Hereinafter, another embodiment of the jig will be described.

The corner at the upper end of the cylindrical receiving jig may be formed in a round shape or an appropriate curved surface, or may be formed so as to be inclined upward and radially inward. This is preferable for smoothly fitting the container lid 100. Before or after disposing the sealing liner 7, the inside of the skirt wall 4 of the container lid 100 is fitted to and supported by the receiving jig, and then the inner peripheral surface of the cylindrical forcing jig is formed. By moving axially downward along the outer peripheral surface of the skirt wall 4, each of the tamper-evident pieces 10 is transformed into a substantially circumferentially continuous tamper-evident hem 50 in the same manner as described above. Let me do. When the forcing operation is performed after the sealing liner 7 is provided, it is necessary to prevent the receiving jig from contacting the sealing portion of the sealing liner 7 as described above. In the process in which each of the tamper-evident pieces 10 is simultaneously swung about each of the bridging portions 12 as the center of rotation, the inner surface of each of the locked projections 40 of the tamper-evident piece 10 is attached to the receiving jig. By being pressed against the outer peripheral surface, each turning of the tamper-evident piece 10 is completed, and at the same time, each of the tamper-evident pieces 10 is formed into a ring shape substantially continuous in the circumferential direction in the same manner as described above. Tamper-evident hem 50
Is formed. Simultaneously with the formation of the tamper-evident hem 50, each of the locked projections 40 allows the container opening 202
The locked ridge 60 locked by the locking jaw 206 is formed. The locked ridge 60 is formed to extend substantially annularly. As will be easily understood from the above description, the outer diameter of the outer peripheral surface of the cylindrical receiving jig is formed to be substantially the same as the minimum inner diameter portion of the inner peripheral surface of the locked ridge 60. I have. By performing the above compulsory work,
Container lid 100 with tamper-evident hem 50, and thus container lid 100 with tamper-evident properties
Is formed. After the tamper-evident hem portion 50 is formed on the container lid 100, the forcing jig is moved axially upward along the outer peripheral surface of the skirt wall 4 to be separated from the container lid 100. Next, the lower end of the tamper-evident hem portion 50 is supported by a proper jig (not shown) so as not to move downward, and in this state, the cylindrical receiving jig is moved axially downward with respect to the container lid 100. By doing so, it can be easily detached from the container lid 100.

Referring to FIGS. 9 and 10, container lid 100 having tamper-evident hem 50 has female screw 5 formed on the inner peripheral surface of skirt wall 4 and outer peripheral portion of opening 202 of container 200. It is attached to the opening 202 by being locked to a male screw 204 formed on the surface and rotating in the closing direction. In this embodiment, the container 200 is a container formed of polyethylene terephthalate (PET), that is, a so-called PET bottle.
The container 200 contains contents such as soft drinks. The sealing liner 7 arranged at the upper end in the skirt wall 4 is pressed against the upper end surface of the opening 202, and the opening 202 is sealed. The locked ridge 60 of the tamper-evident hem 50 is locked to the locking jaw 206 of the container opening 202 (located below the locking jaw 206).

At the time of closing the container lid 100, the end faces of the ratchet pawls 4a formed at the lower end of the skirt wall 4 in the capping direction are respectively connected to the ratchet pawls 10a formed on the respective side faces of the tamper-evident piece 10. By contacting the respective end surfaces on the opening direction side, relative rotation between the skirt wall 4 and the tamper-evident hem portion 50 is prevented, so that each of the bridging portions 12 is not broken. Also,
When the inner tip of the locked ridge 60 gets over the locked jaw 206 of the container 200, the entire tamper-evident hem 50 has a slight pivoting motion about each of the bridging portions 12 and its elasticity. Both actions of the deformation are performed, and the overcoming operation is smoothly performed without any trouble. The above-described elastic deformation of the entire tamper-evident foot portion 50 is allowed by the fact that the container lid 100 is formed of polyethylene, which is a relatively soft synthetic resin. Furthermore, even when the tamper-evident hem 50 receives a tensile force in the circumferential direction at the time of overcoming, each of the locked projections 20 of the tamper-evident piece 10 forming the tamper-evident hem 50 faces each other. The locking of the tamper-evident piece 10 does not come off due to being locked in the locking groove 30 and the circumferential elastic deformation of each of the locked projections 20. Furthermore, even if the tamper-evident hem portion 50 receives a force directed outward in the radial direction, the tamper-evident piece 1
0 on both sides 21a, 22 of the locked projection 20
The tamper-evident piece 10 does not come off the lock due to the gentle inclination formed on both the introduction surfaces 31a of the lock groove 30 and the lock groove 30.

In order to use the contents contained in the container 200, the container lid 100 attached to the opening 202 of the container 200 is first opened by the user's hand (rotated in the opening direction). When this is done, the locked ridges 60 of the tamper-evident hem 50 are prevented from moving upward in the axial direction by the lower surface of the locking jaw 206, so that each of the bridging portions 12 is broken. . Each of the tamper-evident pieces 10 forming the tamper-evidence skirt 50,
Due to the fact that the locked ridge 60 of the tamper-evident hem portion 50 is forced upward in the axial direction on the lower surface of the locking jaw portion 206, a force for circumferentially separating acts. The locked step portion 23 of the locked projection 20 of one of the tamper evidence pieces 10 adjacent to each other in the circumferential direction is
Since the tamper-evident piece 10 is locked in the locking step 34 of the locking groove 30 in the other tamper-evidence piece 10, the tamper-evidence hem 50 substantially continuous in the circumferential direction is not released, and the ring shape is reduced. Will be retained. As a result, the tamper-evident hem 50 is detached from the lower end of the skirt wall 4 of the container lid 100 and remains in the opening 202 of the container 200. Therefore, the container lid 100 is removed from the opening 202 of the container 200. (Opened). The tamper-evident property of the container lid 100 is ensured. Since the container 200 is opened, the user can ingest the contents in the container 200, for example, a beverage. When the container lid 100 is opened, each of the ratchet claws 4 a formed at the lower end of the skirt wall 4 on the closing direction side has a ratchet claw 10 a formed on each side surface of the tamper-evident piece 10. Of the skirt wall 4 and the tamper-evident hem 50 are allowed to rotate relative to each other in a direction away from the end face on the opening direction side of the bridge.
The breaking of each of the two is easily accomplished.

As another embodiment of the closure of the container lid 100, each of the tamper-evident pieces 10 is shown in FIGS.
While maintaining the state at the time of molding shown in FIG.
Female screw 5 formed on the inner peripheral surface of
02 is locked in a male screw 204 formed on the outer peripheral surface of the container 2 and rotated in the closing direction so that the container lid 100 is opened.
02 can also be attached. In this embodiment, the container lid 10 attached to the container opening 202 is next.
The tamper-evident pieces 10, which are arranged in a substantially flat attitude and in a mutually discontinuous manner, around the lower end of the skirt wall 4 in the radial direction, respectively, are placed axially downward, that is, Opening 202
Of the tamper-evidence pieces 10 at the same time, and each of the bridging portions 12 is turned around the turning center. This forcing operation can be easily performed by using the same forcing jig as described above.

When each of the tamper-evident pieces 10 is forced downward in the axial direction as described above, and is simultaneously turned around each of the bridging portions 12 as described above, the tamper-evident pieces 10 are engaged in the same manner as described above. The leading end of the stop portion 22 is the introduction portion 31.
And is fitted in the receiving portion 32 of the locking groove 30. When the turning of each of the tamper-evident pieces 10 is completed, each of the tamper-evident pieces 10 is formed into a ring shape that is substantially continuous in the circumferential direction. The turning of each of the tamper-evident pieces 10 ends (stops) when the radially inner side (the lower surface before the start of turning) of each of the tamper-evident pieces 10 comes into contact with the outer peripheral surface of the locking jaw 206 of the container 200. ). At the same time, the locked step portion 23 of the locked portion 22 of the locked projection 20 is locked to the locking step portion 34 of the receiving portion 32 relatively beyond the introduction portion 31 of the locking groove 30. . As a result, the movement of each of the tamper-evident pieces 10 in the direction apart from each other in the circumferential direction is locked. Each of the tamper-evident pieces 10 is formed into a substantially continuous ring shape in the circumferential direction to form a tamper-evident foot 50.

At the same time as the formation of the tamper-evident hem 50, each of the locked projections 40 allows the container opening 20 to be opened.
The locked ridge 60 locked to the second locking jaw 206 is formed. The locked ridge 60 is formed to extend substantially annularly. Since the above-described forced operation is performed with the container lid 100 closed, the locked projections 60 are formed by each of the locked projections 40, and at the same time, the locked projections 60 are (Located below the locking jaw 206). Container lid 100
By performing the above-mentioned forced work in a state where the container 200 is closed (attached) to the container 200, the tamper-evident hem 5
Thus, a container lid 100 with zeros, and thus a container lid 100 with tamper-evident properties, will be formed.
At the time of opening, each of the tamper-evident hem pieces 50 forming the tamper-evident hem section 50 has the locked ridge 60 of the tamper-evident hem section 50 on the lower surface of the locking jaw 206 in the axially upward direction. The tamper-evident hem 50 receives a radially outward force due to being forced toward it. However, as described above, each of the introduction surfaces 31 a in the introduction portion 31 of the locking groove 30 formed in each of the tamper evidence pieces 10 and the both side surfaces 21 a of the base end portion 21 of the locked projection 20. Each and the locked part 2
2 are formed so as to be gently inclined in a direction away from each other as they go upward, and furthermore, as described above, the tamper-evident foot portion 50a.
Is formed, the base end 2 of the locked projection 20 is formed.
1 are engaged with the corresponding introduction surfaces 31a of the introduction portion 31 of the engagement groove 30 in a substantially aligned manner, so that the engagement of each of the tamper-evident pieces 10 is prevented from being released. You.

In the container lid 100 according to the present invention, the tamper-evident skirt portion is connected to the lower end of the skirt wall 4 via a plurality of breakable bridging portions 12 at circumferential intervals. A plurality of tamper-evident pieces 10 having substantially the same configuration. Each of the tamper-evident pieces 10 is formed so as to have a substantially circular arc shape, and is formed in the radial direction of the skirt wall 4 in a molding state. The tamper-evident piece 10 is positioned so that it extends tangentially on the outside and has a top on the top side. A locking groove 30 is formed on the lower surface, and a locked projection 40 is formed on the lower surface of the outer edge in the radial direction. The above-described basic configuration of the tamper-evident hem portion has a simple form in which circular arc-shaped plate members are arrayed in a ring shape. Since only the groove 30 and the locked projection 40 are formed, the configuration of the tamper-evident hem can be significantly simplified. as a result,
The structure of the mold for molding can be simplified, so that the production cost of the mold can be reduced and the production speed can be increased.

In the container lid 100 according to the present invention, when each of the tamper-evident pieces 10 is forced downward in the axial direction and is simultaneously turned around each of the bridging portions 12, the tamper-evident pieces 10 Each of the locked projections 20 is locked in the corresponding locking groove 30, and the tamper-evident hem is formed to be substantially continuous in the circumferential direction below the lower end of the skirt wall 4, and the tamper-evident hem is formed. The locked ridges 60 locked by the locking jaws 206 of the container opening 202 radially inside the tamper-evident hem 50 by each of the locked projections 40 of the piece 10.
Is formed. Therefore, while being discontinuous in the circumferential direction in the state at the time of molding, the forcing is performed while the skirt wall 4 is attached to the opening 202 of the container 200, so that the skirt wall 4 is easily formed substantially continuous in the circumferential direction. The tamper-evident foot 50 can be provided, and tamper-evident characteristics can be secured.

In the container lid 100 according to the present invention, the tamper-evident piece 10 in the molded state that is discontinuous in the circumferential direction in each of the state where the tamper-evident piece 10 is not mounted on the opening 202 of the container 200 and the state where it is mounted. Can be deformed into a tamper-evident hem 50 having a ring shape substantially continuous in the circumferential direction. Therefore, the completed container lid 100 and the intermediate container lid 100
In any form, it can be supplied to a maker of contents.

In the container lid 100 according to the present invention, the locked projection 20 formed at one end of each of the tamper-evident pieces 10 has a base end 21 extending at a constant width.
And a distal end portion following the base end portion 21. The distal end portion constitutes a locked portion 22 having a pair of locked step portions 23 protruding to both sides in the width direction, and each of the tamper evidence pieces 10 The locking groove 30 formed at the other end of the tamper-evident piece 10 extends from the other end toward the one end at a predetermined depth on the lower surface of the tamper-evident piece 10, and has a corresponding locking projection 20. An introduction portion 31 having a pair of introduction surfaces 31 a having a width smaller than the maximum width of the engagement portion 22, and receiving the locked step portion 23 of the engagement protrusion 20 which is wider than the introduction portion 31. The receiving projection 32 includes a pair of receiving surfaces 32a having a width capable of forming the receiving portion 32 and a receiving portion 32 having a locking step portion 34.
0 is locked to the locking step 34 of the corresponding locking groove 30 so that the tamper-evident foot 50 substantially continuous in the circumferential direction is formed. Have been. According to this configuration, as described above, before the container lid 100 is attached to the container 200,
In any case, the work of forming the tamper-evident hem portion 50 can be easily and practically performed. Further, a significantly simplified configuration of the tamper-evident foot portion can be easily realized in practical use.

In the container lid 100 according to the present invention, the tamper-evident piece 10
Each of the introduction surfaces 31a in the introduction portion 31 of the engagement groove 30 formed in each of the above, and both the side surfaces 21a and 22a in the base end portion 21 and the engagement portion 22 of the locked projection 20 face upward. Is formed so as to be gently inclined in a direction away from each other in accordance with the following formula. Therefore, not only when a relatively soft synthetic resin such as polyethylene is used as a material, but also a hard synthetic resin such as PET is used as a material. Even in this case, it is possible to easily perform the forcible removal from the tamper-evident foot portion during molding. On the other hand, in the container lid 100, each locked step portion 23 of the locked projection 20 corresponds to the locking step portion 34 of the locking groove 30.
In the state where the tamper-evident hem 50 substantially continuous in the circumferential direction is formed by being locked to the
The two side surfaces 21a of the base end portion 21 are configured to be substantially aligned with and engaged with the corresponding introduction surfaces 31a of the introduction portion 31 of the locking groove 30, so that the tamper-evident hem portion 50 The inclined introduction surface 3 in the introduction portion 31 of the locking groove 30 even when receiving a force directed outward in the radial direction.
1a, at the base end 21 of the locked projection 20;
Since the relative movement in the radial direction with respect to the corresponding inclined side surfaces 21a is prevented, it is possible to prevent each of the tamper-evident pieces 10 from being unlocked. Since the female screw 5 is formed on the inner peripheral surface of the skirt wall 4, the final release is performed by turning. According to the present invention, a container lid 100 having a tamper-evident property is provided.
Since it can be molded by PET, it can be applied to a so-called PET bottle molded of the same material. As a result, the container lid 100 according to the present invention is
When applied to ET bottles, in separate collection work,
It is not necessary to separate the tamper-evident hem 50 remaining in the opening 202 from the PET bottle by breaking the hem 50 with a knife or the like as in the conventional case. The PET bottle can be discarded with the evidence foot 50 remaining. Therefore, even if the container lid 100 according to the present invention is applied to a so-called PET bottle, it becomes possible to remarkably facilitate the sorting and collecting work.

As described above, the synthetic resin container lid 100 having the tamper-evident property according to the present invention has been described based on the embodiment. However, the present invention is not limited to the illustrated embodiment. Various changes or modifications can be made without departing from the scope of the idea. For example, in the above embodiment, as shown in FIG. 4, when the container lid 100 is formed (in a state where the tamper-evident piece 10 is not forced downward in the axial direction), each of the tamper-evidence pieces 10 is formed. Is the skirt wall 4 looking tangentially
Of the skirt wall 4 is positioned so as to extend further radially outward from the vicinity of the outside in the radial direction and in a direction substantially perpendicular to the axis, and the top of the upper surface is a plane perpendicular to the axis and coincides with the lower end surface of the skirt wall 4 (See FIG. 4), but the tamper-evident piece 1
0, the upper surface of each of the tamper-evident pieces 10 is axially upward as the upper surface of each of the tamper-evident pieces 10 moves further radially outward from near the radially outer side of the skirt wall 4. In some embodiments, it is inclined.

[0042]

According to the synthetic resin container lid having the tamper-evident characteristic of the present invention, it is possible to simplify the structure of the tamper-evident skirt, and as a result, the mold for molding is formed. The structure can be simplified, thus making it possible to reduce the production costs of the mold and to increase the production speed. Further, even when a relatively hard synthetic resin such as PET is used as a material, forcible removal from the tamper-evident foot portion at the time of molding can be easily performed. Furthermore, even when applied to a so-called PET bottle, it is possible to greatly facilitate the separate collection operation.

[Brief description of the drawings]

FIG. 1 is a plan view of a synthetic resin container lid having tamper-evident characteristics configured according to the present invention.

FIG. 2 is a perspective view of a container lid shown in FIG.

FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2, showing only one half of the axis with respect to the axis;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a perspective view of a tamper-evident piece.

6 is a plan view showing the tamper-evident piece shown in FIG. 5 in a developed state.

7 is a cross-sectional view of a container lid in a state in which a tamper-evident hem portion of the container lid shown in FIG. 1 is formed so as to be continuous in a circumferential direction, and only a half of one side with respect to an axis is shown in section.

FIG. 8 is an enlarged view of a connection portion of tamper-evident pieces adjacent in the circumferential direction in the container lid shown in FIG. 1 as viewed from the outside in the radial direction.

9 is a perspective view showing a state in which the container lid shown in FIG. 7 is attached to a synthetic resin container.

FIG. 10 is a cross-sectional view taken along the line CC of FIG. 9, showing only one half of the axis with respect to the axis;

[Explanation of symbols]

 2 Top Wall 4 Skirt Wall 4a Ratchet Claw 10 Tamper Evidence Piece 10a Ratchet Claw 12 Bridge 20 Locked Protrusion 21 Base End 21a Side of Base End 22 Locked Part 22a Side of Locked Part 23 Covered Locking step portion 30 Locking groove 31 Introducing portion 31a Introducing surface of the introducing portion 32 Receiving portion 34 Locking step portion 40 Locked protruding portion 50 Tamper-evident hem portion 60 Locked protruding portion 100 Container lid 200 Container 202 Container Opening 206 Locking jaw

Claims (5)

[Claims] 1. A synthetic resin container lid having tamper-evident characteristics, which is applied to a container having an external thread formed on an outer peripheral surface of an opening and a locking jaw located below the external thread, A top wall, a skirt wall hanging down from the top wall, a female screw engaging with the male screw is formed on an inner peripheral surface of the skirt wall, and a tamper-evident hem portion is provided at a lower end of the skirt wall. In a synthetic resin container lid with tamper-evident properties, the tamper-evident skirt is connected to the lower end of the skirt wall via a plurality of breakable bridges at intervals in the circumferential direction. A plurality of tamper-evident pieces having substantially the same configuration as each other, each of which is formed to have a substantially circular arc shape and has a radius of the skirt wall in a state at the time of molding. The tamper-evident piece is positioned at one end in the longitudinal direction, and is engaged with the lower surface at the other end in the longitudinal direction. A locking groove is formed on the lower surface of the radially outer edge, and a locked projection is formed on the lower surface. Each of the tamper-evident pieces is forced downward in the axial direction and simultaneously pivoted about each of the bridging portions. And, each locked projection of the tamper-evident piece is locked in the opposite locking groove, and the tamper-evident hem is formed to be substantially continuous in the circumferential direction below the lower end of the skirt wall,
Each of the locked projections of the tamper-evident piece forms a locked ridge that is locked to the locking jaw of the container opening on the radially inner side of the tamper-evident skirt. A synthetic resin container lid having tamper-evident characteristics. 2. A synthetic resin container lid having tamper-evident characteristics, which is applied to a container in which a male screw and a locking jaw located below the male screw are formed on the outer peripheral surface of the opening, A top wall, a skirt wall hanging down from the top wall, a female screw engaging with the male screw is formed on an inner peripheral surface of the skirt wall, and a tamper-evident hem portion is provided at a lower end of the skirt wall. In a synthetic resin container lid with tamper-evident properties, the tamper-evident skirt is connected to the lower end of the skirt wall via a plurality of breakable bridges at intervals in the circumferential direction. A plurality of tamper-evident pieces having substantially the same configuration as each other, each of which is formed to have a substantially circular arc shape and has a radius of the skirt wall in a state at the time of molding. The tamper-evident piece is positioned at one end in the longitudinal direction, and is engaged with the lower surface at the other end in the longitudinal direction. A synthetic resin container lid having tamper-evident characteristics, wherein a stop groove is formed and a locked projection is formed on a lower surface of a radially outer edge. 3. A locked projection formed at one end of each of the tamper-evident pieces, a base end extending at a constant width,
A leading end portion following the base end portion, the leading end portion protruding on both sides in the width direction, forming a locked portion having a pair of locked step portions,
The locking groove formed at the other end of each tamper-evident piece extends at a predetermined depth from the other end toward the one end on the lower surface of the tamper-evident piece, and the corresponding locked An introduction portion having a pair of introduction surfaces having a width smaller than the maximum width of the locked portion of the projection; and a width wider than the introduction portion and capable of receiving the locked step portion of the locked projection. By including a receiving portion having a pair of receiving surfaces having a locking step and a locking step, each locked step of the locked projection is locked to the locking step of the corresponding locking groove, The synthetic resin container lid having tamper-evident characteristics according to claim 1 or 2, wherein a tamper-evident skirt portion substantially continuous in a circumferential direction is formed. 4. In the state at the time of molding, each of the introduction surfaces of the introduction portions of the engagement grooves formed on each of the tamper evidence pieces, and the base end of the engagement projection and both side surfaces of the engagement portion. Is formed so as to be gently inclined in a direction away from each other as it goes upward, and each locked step of the locked projection is locked by the locking step of the corresponding locking groove and substantially In the state where the tamper-evident hem portion continuous in the direction is formed, the both side surfaces at the base end portion of the locked projection are substantially aligned with and engaged with the corresponding introduction surfaces at the introduction portion of the engagement groove. The synthetic resin container lid having the tamper-evident property according to claim 3. 5. The synthetic resin container lid having tamper-evident properties according to claim 4, wherein the synthetic resin is polyethylene terephthalate.