WO2020179608A1

WO2020179608A1 - Cap

Info

Publication number: WO2020179608A1
Application number: PCT/JP2020/007990
Authority: WO
Inventors: 靖文黒岩; 伸生川村; 淳史小野; 慎吾梅木
Original assignee: 日本山村硝子株式会社
Priority date: 2019-03-07
Filing date: 2020-02-27
Publication date: 2020-09-10
Also published as: CN113412224B; JP6655741B1; KR20210126105A; CN113412224A; JP2020142836A

Abstract

Provided is a cap capable of preventing a blowoff and an overrun. A cap (1) that is attached to a container opening part so as to cover the same is provided with: a top wall (2); and a substantially cylindrical skirt wall (3) that extends downward from an outer peripheral part of the top wall (2). The skirt wall (3) has a female screw (5) that threadedly engages a male screw formed on the periphery of the container opening part. In the skirt wall (3), the thickness of a lower portion (14) positioned below the female screw (5) is made greater than the thickness of an upper portion (15) positioned above the female screw (5).

Description

cap

The present invention relates to, for example, a cap attached to the mouth of a container for accommodating contents such as beverages.

As shown in FIGS. 3(A) and 3(B), the cap 51 detachably attached to the mouth M of the container by screw connection and configured to perform the capping and opening functions of the container mouth M, Widely used in containers for various beverages (Patent Document 1).

Japanese Patent No. 5291175

By the way, in the conventional cap 51 mounted on the container mouth M by screw coupling, the engagement range (area) of the female screw 52 of the cap 51 to the male screw M1 of the container mouth M becomes narrower as the cap is opened. However, as long as the male screw M1 and the female screw 52 are engaged, the cap 51 will not come off from the container mouth M. However, for example, when the container is filled with a carbonated beverage, the internal pressure of the container increases due to the gas pressure derived from carbon dioxide gas, which pushes up the cap 51 while the male screw M1 and the female screw 52 are engaged. When the skirt wall 53 of the cap 51 is expanded to the extent that it can pass over the male screw M1 and the above engagement is disengaged, a phenomenon called blow-off occurs in which the cap pops off.

Further, in the above-mentioned conventional cap, when the cap is attached to the container mouth portion, if the cap is overtightened, overrun (the female screw of the cap crosses the male screw of the container mouth) occurs, resulting in insufficient closure. There is also a risk of becoming.

The present invention has been made in consideration of the above-mentioned matters, and an object of the present invention is to provide a cap capable of preventing blow-off and overrun.

In order to achieve the above object, a cap according to the present invention is a cap that is attached to a container opening so as to cover the container opening, and is downward from a ceiling wall and an outer peripheral portion of the ceiling wall. A substantially tubular skirt wall that extends is provided, and the skirt wall is provided with a female screw that is screwed into a male screw formed on the outer periphery of the container mouth portion, and is located below the female screw in the skirt wall. The wall thickness of the portion was made larger than the wall thickness of the upper portion located above the female screw (claim 1).

Further, in the cap, in the region from the upper portion to the lower portion of the skirt wall, the wall thickness of the portion excluding the female screw may be increased downward (claim 2).

In the present invention, a cap capable of preventing blow-off and overrun can be obtained.

That is, in the cap of the present invention, since the wall thickness of the lower portion is made larger than the wall thickness of the upper portion, the skirt wall has that much less than the wall thickness of the lower portion equal to or less than that of the upper portion. It is difficult to expand and deform. Therefore, for example, when the container is filled with carbonated beverages, the internal pressure of the container is increased by the gas pressure derived from carbon dioxide gas, whereby the male screw of the container mouth and the female screw of the cap are engaged. Even if a pushing force is applied to the cap as it is, the skirt wall is difficult to expand the diameter as described above, so it is prevented that the skirt wall expands to the extent that it can pass over the male screw and the engagement is disengaged. It is possible to prevent the occurrence of blow-off.

Also, due to the difficulty of expanding the diameter of the skirt wall, it is possible to prevent the occurrence of overrun (the female screw of the cap gets over the male screw of the container mouth).

On the other hand, if the thickness of the part of the skirt wall where the internal thread is formed, excluding the internal thread, is less than or equal to the thickness of the upper part, the diameter increases in this internal thread forming area, and blow-off and overrun occur. However, in the cap of the invention according to claim 2, the female screw is removed in the region from the upper portion to the lower portion of the skirt wall (the region including the female screw forming region). Since the wall thickness of the portion is increased toward the bottom, it is possible to sufficiently prevent the occurrence of blow-off and overrun.

(A) is a bottom view schematically showing a configuration of a cap according to an embodiment of the present invention, and (B) is a sectional view taken along line AA of (A). It is sectional drawing BB in FIG. 1 (A). (A) is a front view showing a conventional synthetic resin cap, and (B) is a front view showing a state in which the cap is attached to the container mouth.

Embodiments of the present invention will be described below with reference to the drawings.

A synthetic resin cap (hereinafter referred to as a cap) 1 shown in FIGS. 1A and 1B is a container having a male screw M1 and an annular protrusion (an example of an engaged portion) M2 as shown in FIG. 3B. The mouth portion M (for example, the mouth portion of a container such as a PET bottle) is attached and used so as to cover the mouth portion M, and is integrally formed of polyethylene by compression molding or injection molding. The material for forming the cap 1 is not particularly limited, and polypropylene or the like is preferably used in addition to the polyethylene used in the present embodiment.

The cap 1 has a substantially circular top wall 2 in a plan view and a substantially cylindrical skirt wall 3 extending downward from the outer peripheral portion of the top wall 2 (see FIGS. 1 (A) and 1 (B)). Here, as shown in FIG. 1B, a knurled groove 4 is provided on the outer peripheral surface of the skirt wall 3, and a female screw 5 is provided on the inner peripheral surface, and the female screw 5 is formed on the outer periphery of the container mouth portion M. It is possible to connect to the external thread M1 that is formed.

Then, when the cap 1 is rotated and attached to the container mouth M such that the male screw M1 of the container mouth M is coupled to the female screw 5 of the skirt wall 3, the inner surface (lower surface) of the top wall 2 shown in FIG. The ring-shaped inner leg (inner ring) 6, the ring-shaped rib 7 and the ring-shaped outer leg (outer ring) 8 which are continuously provided in close contact with the container mouth M, whereby the container mouth M is sealed. Become. That is, when the cap 1 is attached to the container mouth M, the middle foot 6 is inserted into the container mouth M and comes into close contact with the inner peripheral surface of the container mouth M, and the annular rib 7 is the container mouth M. The outer leg 8 is configured to be in close contact with the annular upper end face and the outer peripheral face of the container mouth M.

Further, the cap 1 is a pill fur-proof cap having a function of certifying that it has not been opened (that the cap has never been opened). When the unopened cap 1 attached to the container mouth M is opened (first When the cap 1 is rotated so that the connection between the male screw M1 and the female screw 5 is released (when the cap is opened), the cap 1 separates from the container mouth M, but the tamper evidence connected to the lower part of the skirt wall 3 The band (hereinafter, simply referred to as “band”) 9 (see FIG. 1 (B)) is configured to remain in the container mouth portion M.

That is, a band 9 is connected to the lower part of the skirt wall 3 via an annular weakening portion 10 extending over the entire circumference of the skirt wall 3 (see FIG. 1 (B)), and the annular weakening portion 10 is the skirt wall 3. A slit (perforated) extending intermittently in the circumferential direction of the skirt wall 3 and the band 9 and a bridge (bridge) existing between adjacent slits so as to draw the band 9 up and down. The bridge breaks when pulled by a predetermined force.

Here, in this example, while the outer diameter of the band 9 is made uniform over the top and bottom, the band 9 is configured to project inward toward the inner peripheral side and the amount of protrusion inward increases toward the upper side. Five (one example of a plurality of) hooks (an example of engaging portions) 11 are provided at intervals (equal intervals in this example) in the circumferential direction (see FIGS. 1A and 1B). Each hook 11 is substantially below the annular protrusion M2 (see FIG. 3B) formed below the male screw M1 on the outer circumference of the container mouth M with the cap 1 attached to the container mouth M. It is located at and is locked to the annular protrusion M2 by the opening operation. That is, the hook 11 is configured to be able to be locked to the annular projection M2 from below. The alternate long and short dash line in the lower part of FIG. 2 shows the cross-sectional shape of the portion where the hook 11 is not provided.

Further, as shown in FIGS. 1B and 2, on the inner peripheral side of the band 9, above the hook 11, it projects inward from the inner surface of the upper end of the band 9, and the maximum projecting amount is the hook 11. A fitting portion 12 smaller than the maximum protrusion amount (the inner diameter is larger than the inner diameter of the hook 11) over the entire circumference of the band 9, and further, above the fitting portion 12, an inclined portion having an inner diameter that increases toward the upper side. 13 are in a row.

Thus, in the unopened state attached to the container opening portion M, the annular protrusion M2 is located inside the inclined portion 13 or above it, and when the cap 1 is rotated in the opening direction from this state, the container opening portion The cap 1 is relatively raised with respect to M, the fitting portion 12 is fitted into the annular protrusion M2, and the hook 11 is locked to the annular protrusion M2 from below. Further, when the cap 1 is continuously rotated in the opening direction, the annular weakening portion 10 is eventually broken and the band 9 remains in the container mouth portion M, while the cap body composed of the top wall 2 and the skirt wall 3 above the cap body is a container. It will be separated from the mouth M.

Therefore, the inclined portion 13 contacts the annular protrusion M2 and the fitting portion 12 fits on the outer peripheral surface of the annular protrusion M2 until the hook 11 is locked to the annular protrusion M2 from below. As a result, the band 9 is prevented from being lifted up obliquely, and the annular weakened portion 10 is fractured substantially uniformly without being biased, so that the tamper evidence is improved. When the stopper is opened, the fitting portion 12 fits on the outer peripheral surface of the annular protrusion M2 of the container mouth portion M, and the hook 11 surely engages the annular protrusion M2, so that the annular weakening portion 10 is broken. It is possible to prevent the so-called slip-out, in which the hook 11 gets over the annular protrusion M2.

Then, in this example, as shown in FIG. 2, in the skirt wall 3, the wall thickness of the lower portion 14 located below the female screw 5 (female screw forming region 5A) is reduced to that of the upper portion 15 located above the female screw 5. It is larger than the wall thickness.

Here, the lower portion 14 is a portion of the skirt wall 3 that is continuous below the female thread 5 (female thread forming region 5A). The inner peripheral surface of the lower portion 14 extends so as to be separated from the outer side (outer peripheral surface) toward the lower side. Further, the inner diameter of the lowermost portion 16 connected below the lower portion 14 increases toward the lower side, and the rate of change of the inner diameter in the vertical direction is larger than the rate of change of the inner diameter of the lower portion 14 in the vertical direction. ing.

On the other hand, the upper portion 15 is a portion of the skirt wall 3 that is continuous above the female thread 5 (female thread forming region 5A). The inner peripheral surface of the upper portion 15 also extends so as to be separated from the outer side (outer peripheral surface) toward the lower side. Further, above the upper portion 15, a corner portion 17 extending so that the inner peripheral surface and the outer peripheral surface bend inward is connected.

Since the female screw 5 extends spirally on the inner peripheral surface of the skirt wall 3, the position and vertical width of the female screw 5 (female screw forming region 5A) are not uniform in the circumferential direction of the skirt wall 3. It will differ depending on the phase, and accordingly, the vertical widths of the lower portion 14 and the upper portion 15 will also differ depending on the phase.

Thus, in this example, since the thickness of the lower portion 14 is made larger than that of the upper portion 15, the thickness of the lower portion 14 is equal to or less than the thickness of the upper portion 15, The skirt wall 3 is less likely to be expanded and deformed accordingly. Therefore, for example, when a carbonated beverage is filled in the container, the internal pressure of the container is increased by the gas pressure derived from the carbon dioxide gas, which causes the cap 1 to remain in the state in which the male screw M1 and the female screw 5 are engaged. Even if a pushing force is applied, since the skirt wall 3 is difficult to expand in diameter as described above, it is prevented that the skirt wall 3 expands to such an extent that the male screw M1 can be overcome and disengages from the engagement. It is possible to prevent blow-off from occurring.

Also, due to the difficulty of expanding the diameter of the skirt wall 3, it is possible to prevent the occurrence of overrun (the female screw of the cap gets over the male screw of the container mouth).

On the other hand, if the wall thickness of the portion of the female screw forming region 5A excluding the female screw 5 is equal to or less than the wall thickness of the upper portion 15, the diameter is increased in the female screw forming region 5A to prevent blow-off and overrun. In this example, the wall thickness of the portion of the skirt wall 3 from the upper portion 15 to the lower portion 14 (the region including the female screw forming region 5A) excluding the female screw 5 is sufficient. Since it is made larger toward the bottom, it is possible to sufficiently prevent the occurrence of blow-off and overrun. The two-dot chain line shown in the upper part of FIG. 2 indicates the cross-sectional shape of the portion of the skirt wall 3 excluding the female screw 5.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be variously modified and implemented without departing from the gist of the present invention. For example, the following modifications can be mentioned.

In the example of FIG. 2, from the upper end of the upper portion 15 to the lower end of the lower portion 14, the wall thickness of the portion excluding the female screw 5 is increased at a constant rate toward the lower side, but the thickness is not limited to this, for example. The ratio may be changed in the middle, or a portion where the wall thickness of the portion excluding the female screw 5 does not change may be provided in the vertical direction.

Further, between the lower part 14 and the lowermost part 16, a part which does not correspond to either the lower part 14 or the lowermost part 16 may be provided, or the lowermost part 16 is not provided and the lower part 14 is not provided. May extend to the lower end of the skirt wall 3.

A portion that does not correspond to either the upper portion 15 or the corner portion 17 may be provided between the upper portion 15 and the corner portion 17.

Needless to say, the above modified examples may be appropriately combined.

1 Cap 2 Top wall 3 Skirt wall 4 Knurled groove 5 Female thread 5A Female thread formation area 6 Middle foot 7 Ring rib 8 Outer foot 9 Tamper evidence band 10 Ring weakening part 11 Hook (engagement part)
12 Fitting part 13 Inclined part 14 Lower part 15 Upper part 16 Bottom part 17 Corner part 51 Cap 52 Female screw M Container mouth part M1 Male screw M2 Circular protrusion (engaged part)

Claims

A cap that is attached to the container mouth so as to cover the container mouth.
The top wall,
It is provided with a substantially tubular skirt wall extending downward from the outer peripheral portion of the top wall.
The skirt wall is provided with a female screw that is screwed into a male screw formed on the outer periphery of the container mouth,
A cap in which the wall thickness of the lower portion of the skirt wall located below the female screw is larger than the wall thickness of the upper portion located above the female screw.
The cap according to claim 1, wherein in the region from the upper portion to the lower portion of the skirt wall, the wall thickness of the portion excluding the female screw becomes larger toward the lower side.