JPH0346380B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a container lid made of synthetic resin having pilfer-proof properties, and more specifically, a container lid having a male thread formed on the outer peripheral surface and an annular locking flange located below the male thread. The present invention relates to a synthetic resin container lid that has pilfer-proof properties and is applied to containers with a mouth and neck that are pilfer-proof.

Japanese Unexamined Patent Publication No. 56-74445 discloses a synthetic resin container lid having pilfer-proof properties, which is applied to a container having a neck portion as described above. This container lid has a top wall and a cylindrical skirt wall depending from the periphery of the top wall. A circumferentially extending break line is formed in the skirt wall, and the skirt wall is divided into a main portion above the break line and a pilfer-proof hem below the break line. The inner surface of the main part is formed with a female thread that is screwed together with the male thread formed on the mouth and neck, and the inner surface of the pilfer-proof hem protrudes radially inward and is formed on the mouth and neck. A plurality of locking flap pieces that are locked to the lower surface of the annular locking flange are formed at intervals in the circumferential direction.

As can be easily understood from the description in JP-A No. 56-74445, such container lids have a variety of advantages compared to other types of known synthetic resin container lids having pilfer-proof properties. It has the following advantages.
However, according to the experience of the present inventor, it has been found that there are the following problems or drawbacks to be solved. When attaching the above-mentioned container lid to the mouth and neck to seal the mouth and neck, the container lid is fitted onto the mouth and neck, and then the container lid is rotated in a predetermined direction to connect the female thread of the container lid to the male and female threads of the mouth and neck. Screw it into the thread. In this way, the container lid moves downward in the axial direction with respect to the mouth and neck as the container lid rotates and the female thread and the male thread are engaged with each other. and,
At this time, the locking flap piece formed on the inner surface of the hem of the pilfer-proof passes through the annular locking flange formed on the neck and neck part, but when passing through the ring-shaped locking flange, The locking flap piece is elastically deflected radially outward by interference with the locking flange, and when it has completely passed through the annular locking flange, the locking flap piece elastically returns to its original state. The upper edge of the locking flap piece thus locks onto the lower surface of the annular locking flange. However, in the above-mentioned container lid, the locking flap piece does not return to its original state sufficiently securely after completely passing through the annular locking flange, and therefore the locking flap piece does not return to its original state in a sufficiently reliable manner after completely passing through the annular locking flange. There is a tendency for the upper edge to be insufficiently locked, resulting in insufficient pilfer-proof properties.

The present invention has been made in view of the above facts, and its main purpose is to provide a pill that eliminates the above-mentioned problems and drawbacks found in the container lid disclosed in JP-A-56-74445. An object of the present invention is to provide an improved synthetic resin container lid having a safe property.

As a result of extensive studies, the present inventor has determined that a pilfer-proof hem is provided on the outer surface facing the inner surface of the pilfer-proof hem of each of the plurality of locking flap pieces formed on the inner surface of the pilfer-proof hem. Forming at least one auxiliary protruding piece protruding toward the inner surface of the hem allows the elasticity of the locking flap piece itself to be reduced after each of the locking flap pieces passes through the annular locking flange formed on the neck and neck part. In addition to the restoring action, the elastic restoring action of the auxiliary protruding piece works, whereby the locking flap piece returns to its original state with sufficient certainty, thus ensuring that sufficient pilfer-proof properties are obtained. I found it.

That is, according to the present invention, the container has pilfer-proof characteristics for a container having a neck portion in which a male thread and an annular locking flange 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 that hangs down from the periphery of the top wall, the skirt wall having a circumferentially extending fracture line, and the skirt wall having a circumferentially extending fracture line. It is divided into a main part above the break line and a pilfer-proof hem below the break line, and the inner surface of the main part has a female thread that is screwed into the male thread of the mouth and neck part. In a container lid in which a thread is formed and a plurality of locking flap pieces protruding radially inward are formed on the inner surface of the pilfer-proof hem at intervals in the circumferential direction; The outer surface of each of the pieces facing the inner surface of the pilfer-proof hem is provided with at least one auxiliary protruding piece projecting therefrom toward the inner surface of the pilfer-proof hem. A container lid is provided.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of synthetic resin container lids improved in accordance with the present invention will now be described in more detail with reference to the accompanying drawings.

To explain with reference to FIG.
It has an integrally formed body with a cylindrical skirt wall 6 depending from the periphery of the body. Such a body can be formed from a suitable synthetic resin material by injection molding or compression molding. A break line 8 extending in the circumferential direction is formed in the skirt wall 6 , and the skirt wall 6 has a main portion 10 above the break line 8 and a pilfer below the break line 8 . It is divided into a proof hem portion 12. The break line 8 may be a so-called score formed by reducing the thickness of the material, but in the illustrated example, the break line 8 is formed by a plurality of circumferentially extending slits ( The pilfer-proof hem 12 is made up of a plurality of bridging parts 16 remaining between the slits 14, and the pilfer-proof hem 12 is connected to the main part 10 by the plurality of bridging parts 16. It is connected. As clearly illustrated in FIG. 1, it is generally advantageous for main portion 10 to be relatively thick and pilfer-proof skirt 12 to be relatively thin.

The inner surface of the main portion 10 of the skirt wall 6 has a female thread 1.
8 is formed. Further, an annular protrusion 20 is formed at the lower end of the outer surface of the main portion 10, and a finger can be placed on the area above the annular protrusion 20 to rotate the container lid 2. An uneven shape or a knurled shape 22 is formed to prevent slippage.

On the other hand, on the inner surface of the pilfer-proof hem 12 of the skirt wall 6, a plurality of locking flap pieces 24 are formed at intervals in the circumferential direction. Each of the locking flap pieces 24 is attached to the pilfer-proof hem 1.
It projects radially inwardly from a base 26 connected to the inner surface of 2. Referring to FIGS. 2 and 3 in conjunction with FIG. 1, in the illustrated embodiment, the base edge 26 of each locking flap piece 24 is
The rotation direction of the container lid 2 when the container lid 2 is attached to the mouth and neck of the container as described later in the axial direction (clockwise direction when viewed from above in FIG. 1) is reversed (see FIG. 1). It extends downward while forming an acute angle α (counterclockwise when viewed from above). The base edge 26 projects radially inward at an angle opposite to the rotational direction. The upper edge 28 of each locking flap piece 24 slopes downwardly from the base edge 26 toward the free end by a slight angle β, and the lower edge 30 forms an acute angle γ upwardly from the base edge 26 toward the free end. It's sloped. The above angle β is determined by attaching the container lid to the neck of the container as described below.
When the locking flap piece 24 is elastically deflected radially outward due to the interference of the annular locking flange formed at the mouth and neck when the flap is installed, the upper edge 26 becomes substantially horizontal. It is convenient to set it to .

Although it is preferred that the locking flap piece 24 has the above-described configuration in the illustrated embodiment, the configuration of the locking flap piece 24 is not limited to the above-described configuration; for example, the base edge 26 may be Various forms of locking, such as a form in which the base edge 26 extends substantially parallel to the base edge 26, or a form in which the base edge 26 extends substantially horizontally and projects axially upwardly and radially inwardly from the base edge 26. A flap piece 24 can also be formed.

In the container lid 2 improved according to the present invention, the pill is attached to the outer surface 32 of each of the plurality of locking flap pieces 24 facing the inner surface of the pill-proof hem 12. It is important that at least one auxiliary protruding piece 34 is formed which protrudes towards the inner surface of the fair-proof hem 12.

As clearly shown in FIGS. 2 and 3, in the illustrated embodiment, each of the locking flaps 24 has a tongue-shaped auxiliary projection 34 on its outer side 32. The auxiliary projecting piece 34 has a base edge 36 connected to the outer surface 32 of the locking flap piece 24 at an intermediate portion thereof, which is substantially parallel to the axial direction when viewed in the protruding direction of the locking flap piece 24. 36, the rotation direction of the container lid 2 when the container lid 2 is attached to the mouth and neck of the container (clockwise direction when viewed from above in FIG. 1) is reversed (counterclockwise in FIG. 1). direction) and protrudes toward the inner surface of the pilfer-proof hem 12. Of course, the auxiliary protruding piece 34 is not limited to such a form; for example, the base edge 36 of the auxiliary protruding piece 34
The base edge 36 of the auxiliary protruding piece 34 can be made to extend substantially horizontally so as to extend downward at an acute angle in the rotational direction or in the opposite direction with respect to the axial direction. The auxiliary protruding piece 34 can also be inclined upward or downward in the axial direction from the base edge 36 so as to protrude toward the inner surface of the pilfer-proof hem 12.

4 to 7 illustrate examples of modifications and modifications of the auxiliary protruding piece 34. In FIG. 4, three tongue-shaped auxiliary protrusions 34 are formed on the outer surface 32 of the locking flap piece 24 at intervals in the direction in which the locking flap piece 24 protrudes. In FIG. 5, a tongue-shaped auxiliary projection 34 is formed whose base edge 36 coincides with the free end edge of the locking flap 24. In FIG. In FIG. 6, a slight bend is formed in the locking flap piece 24 at the middle part when viewed in the protruding direction of the locking flap piece 24, and the base edge of one tongue-shaped auxiliary projecting piece 34 36 is made to match the above-mentioned bent portion. In FIG. 7, a relatively large number of auxiliary protrusions 34 are formed on the outer surface 32 of the locking flap piece 24, and are not tongue-like but needle-like.

Referring again to FIG. 1, in the illustrated example, in addition to the main body as described above, a packing member 38 made of synthetic resin is also provided, which is disposed on the inner surface of the top wall 4 separately from the main body. ing. When the packing member 38 is disposed separately from the main body, the main body is made of a relatively hard synthetic resin material such as polypropylene or hardened polyethylene, and the packing member 38 is made of polyvinyl chloride, ethylene vinyl acetate, or It is generally advantageous to construct it from a relatively soft synthetic resin material, such as flexible polyethylene. The illustrated packing member 38 has a disk shape as a whole, and an outer annular protrusion 40 and an inner annular protrusion 42 are formed on the outer periphery of the lower surface thereof. Such a packing member 38 is produced, for example, by loading a synthetic resin material in a heated and molten state onto the inner surface of the top wall 4 of the main body that has already been molded, and then molding the synthetic resin material by embossing (compression). can be conveniently formed.

Container lid 2 as described above is shown at number 44 in FIG.
Applicable to containers with a known neck and neck as shown in the figure. The neck portion 44 having an open upper end has a substantially cylindrical shape, and has a male thread 46 on its outer peripheral surface and an annular locking flange 48 located below the male thread 46.
is formed. The circumferential side of the annular locking flange 48 slopes downwardly and radially outwardly to define a substantially horizontal annular locking surface on the lower surface of the annular locking flange 48 .

To seal the mouth and neck part 44 by attaching the container lid 2 to the mouth and neck part 44, the container lid 2 is fitted onto the mouth and neck part 44, and the container lid 2 is rotated clockwise when viewed from above in FIG. . In this way, the female thread 18 formed on the container lid 2 is screwed into the male thread 46 formed on the neck portion 44, thereby causing the container lid 2 to move downward in the axial direction as it rotates. . When the container lid 2 is moved downward, each of the locking flap pieces 24 formed on the container lid 2 passes through a male thread 46 formed in the neck 44 and then through an annular locking flange. 48, as shown in FIG. 9, when passing through the annular locking flange 48,
By being interfered with, each of the locking flap pieces 24 is elastically deflected radially outward. When each of the locking flap pieces 24 elastically bends outward in the radial direction, the auxiliary protrusion pieces 34 formed on the outer surface 32 are displaced radially outward, and the free ends thereof become pilfer-proof. It comes into contact with the inner surface of the hem 12 and is then elastically bent between the outer surface of the locking flap piece 24 and the inner surface of the pilfer-proof hem 12 . When the female thread 18 of the container lid 2 is fully screwed into the male thread 46 of the neck portion 44, each of the locking flap pieces 24 has an annular locking flange 48, as shown in FIGS. 8 and 10. completely passes through and is no longer interfered with by the annular locking flange 48, and each of the locking flap pieces 24 and its outer surface 3
The auxiliary protruding piece 34 formed at 2 elastically returns to its original state.

Therefore, as already mentioned, the locking flap piece 2
If the auxiliary protruding piece 34 is not formed on the outer surface 32 of each of the locking flap pieces 24, the elastic return of each of the locking flap pieces 24 to its original state will depend on the elasticity of each of the locking flap pieces 24. Therefore, the locking flap piece 24 tends not to be able to return to its original state with sufficient certainty. However, in the container lid 2 improved according to the present invention, the auxiliary protruding pieces 34 are formed on the outer surface 32 of each of the locking flap pieces 24, and as described above, the locking flap pieces 24
When each of the locking flap pieces 24 passes through the annular locking flange 48, each of the locking flap pieces 24 is elastically deflected, and each of the auxiliary protruding pieces 34 is also elastically deflected.
Therefore, as will be readily understood by comparing and referring to FIGS. 9 and 10, after each of the locking flap pieces 24 has completely passed through the annular locking flange 48, the locking flap In addition to the elastic return action of each of the pieces 24, the elastic return action of each of the auxiliary protruding pieces 34 also acts, and thus the locking flap piece 24
each of which is returned to its original state with sufficient certainty.

When each of the locking flap pieces 24 has been sufficiently returned to its original state, the upper edge 28 of each of the locking flap pieces 24 will open as shown in FIG.
is securely locked to the lower surface of the annular locking flange 48. In addition, when the female thread 18 of the container lid 2 is fully screwed into the male thread 46 of the neck portion 44, as shown in FIG. The inner annular protrusion 42 is brought into close contact with the end surface of the mouth and neck part 44,
The mouth and neck region 44 is thus sealed.

The container lid 2 attached to the mouth and neck part 44 as described above is removed from the mouth and neck part 44, and the mouth and neck part 44 is removed.
When opening the container lid 2, the container lid 2 is rotated in a direction opposite to the direction of rotation when it is attached, that is, in a counterclockwise direction as viewed from above in FIG. In this way, since the female thread 18 formed on the container lid 2 is moved along the male thread 46 formed on the neck portion 44, the container lid 2 does not move upward in the axial direction. However, since the upper edge 28 of the locking flap piece 24 formed on the inner surface of the pill-proof hem 12 of the container lid 2 is locked to the lower surface of the annular locking flange 48 of the neck portion 44, the pill The free-proof hem 12 is prevented from moving upward in the axial direction. Thus, the bridge 16 at the break line 8 formed in the container lid 2
Significant stresses are generated in each of the skirt walls 6
The bridging portion 16 connecting the pilfer-proof hem 12 to the main portion 10 of is broken, and the pilfer-proof hem 12 is separated from the main portion 10. After that, the portion of the container lid 2 other than the pilfer-proof hem 12 can easily move upward in the axial direction, and therefore moves upward in the axial direction in accordance with the rotation of the container lid 2 to close the opening. It is removed from the neck 44, and the mouth and neck 44 are thus opened. On the other hand, the pilfer-proof hem 12 has a mouth and neck area 44.
remain there without being removed from it.

Although several specific examples of the container lid of the present invention have been described above in detail with reference to the accompanying drawings, the present invention is not limited to these specific examples, and various modifications may be made without departing from the scope of the present invention. Needless to say, it is possible to modify or modify.

For example, in the specific example shown, when the container lid is removed from the neck of the container and the neck is opened, the break line formed on the skirt wall is completely broken and the skirt wall becomes the main part. The pilfer-proof hem is completely separated from the pilfer-proof hem, and the main parts of the top wall and skirt wall of the container lid are separated from the neck and neck, but the pilfer-proof hem is configured to remain in the neck. ing. However, if desired, as is already known in metal container closures with pilfer-proof properties, for example, at least one axially extending break line may be formed in the pilfer-proof skirt and in the skirt wall. A part of the circumferential break line formed on the hem of the pilfer-proof is strengthened, so that when the container lid is removed from the neck and the neck is opened, the break line in the axial direction formed on the hem of the pilfer-proof is broken. The pilfer-proof hem is opened from an annular shape to a band shape, while the circumferential break line formed on the skirt wall is not completely broken.
Therefore, the pilfer-proof hem of the skirt wall is not completely separated from the main part, but remains partially connected to the main part,
In this way, the entire container lid including the pilf-proof hem can be removed from the mouth and neck without the pilf-proof hem remaining on the mouth and neck.

[Brief explanation of drawings]

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 sectional view showing a part of the container lid of FIG. 1; FIG. FIG. 3 is a partial sectional view taken along line - in FIG. 1;
4 to 6 are partial sectional views similar to FIG. 1, showing examples of modification or modification of the auxiliary protruding piece. FIG. 7 is a partially cutaway perspective view showing an example of modification or modification of the auxiliary protruding piece. FIG. 8 is a side view, partially in cross section, showing a state in which the container lid of FIG. 1 is attached to the mouth and neck of the container to seal the mouth and neck. FIG. 9 is a partial sectional view showing a state in which the container lid of FIG. 1 is being attached to the mouth and neck of the container. FIG. 10 is a partial sectional view showing a state in which the container lid of FIG. 1 is attached to the mouth and neck of the container to seal the mouth and neck. 2... Container lid, 4... Top wall, 6... Skirt wall, 8... Fracture line, 10... Main part of skirt wall, 12... Pilfer-proof hem of skirt wall, 24... Locking Flap piece, 34...auxiliary protruding piece.

Claims (1)

[Claims] 1. A composition having pilfer-proof properties for a container having a neck portion in which a male thread and an annular locking flange located below the male thread are formed on the outer peripheral surface. The container lid is made of resin and includes a top wall and a cylindrical skirt wall that hangs down from the periphery of the top wall, the skirt wall has a circumferentially extending fracture line, and the skirt wall has a It is divided into a main part above the break line and a pilfer-proof hem below the break line, and the inner surface of the main part has a female thread that is screwed into the male thread of the mouth and neck part. A container lid in which a thread is formed and a plurality of locking flap pieces projecting radially inward are formed on the inner surface of the pilfer-proof hem at intervals in the circumferential direction; The outer surface of each of the pieces facing the inner surface of the pilfer-proof hem is provided with at least one auxiliary protruding piece projecting therefrom toward the inner surface of the pilfer-proof hem. Features a container lid. 2. Each of the locking flap pieces protrudes from the inner surface of the pilfer-proof hem at an angle opposite to the direction of rotation of the container lid when the container lid is attached to the mouth and neck, and the auxiliary protrusion Claim 1: Each of the pieces projects from the outer surface of each of the locking flap pieces at an angle opposite to the direction of rotation of the container cover when the container cover is attached to the mouth and neck. Container lid as described in section. 3. The container lid according to claim 1 or 2, wherein each of the auxiliary projecting pieces is tongue-shaped. 4. The container lid according to claim 1 or 2, wherein a plurality of needle-like auxiliary protruding pieces are formed on the outer surface of each of the locking flap pieces.