HK1262223A1 - Synthetic resin cap - Google Patents

Description

Synthetic resin cap

Technical Field

The present invention relates to a synthetic resin cap to be attached to a mouth of a container containing contents such as drinks.

Background

As a cap to be attached to a mouth portion of a container containing contents such as beverages, a cap configured to be able to confirm whether or not the cap is opened at a glance is widely used. As such a cap, a cap is known which includes a cap body having a skirt (skirt) wall provided with a female screw to be screwed with a male screw of a container mouth portion, and a tamper evident band connected to a lower portion of the skirt wall by an annular weakened portion.

In the above-described conventional cap, in response to an unsealing operation (first opening operation) from a state of being attached to the container mouth, a hook (locking means) provided on the inner periphery of the tamper evident band is locked to an annular protrusion (locking jaw) provided on the outer periphery of the container mouth, and then a connecting bridge (bridge portion) formed between slits defining a seam hole shape between the tamper evident band and the skirt wall is broken, and the cap body and the tamper evident band are separated from each other (see patent document 1). Therefore, whether or not the opening operation is performed can be easily confirmed by visually confirming whether or not the connecting bridge constituting the annular weakened portion is broken.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5554574

Disclosure of Invention

Problems to be solved by the invention

However, in the cap described in patent document 1, since the fitting lower portion having an inner diameter smaller than the outer diameter of the annular protrusion and extending 0.3 to 0.7mm in the vertical direction is provided above the hook on the inner peripheral surface of the tamper evident band, when the cap attached to the container mouth is opened, the cap body is prevented from loosening, and further, the cap body can be prevented from coming off the container mouth without breaking the connecting bridge, so-called coming-off is prevented, and the tamper evident property is good.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a synthetic resin cap which has excellent tamper-evident properties and can suppress an increase in cap opening torque.

Means for solving the problems

In order to achieve the above object, a synthetic resin cap according to the present invention is a cap including a skirt wall provided with a female thread to be screwed with a male thread formed on an outer periphery of a container mouth, and a tamper evident band connected to a lower portion of the skirt wall by an annular weakened portion, wherein a plurality of hooks are provided on an inner peripheral side of the tamper evident band at intervals in a circumferential direction, the hooks being capable of being engaged with an annular protrusion provided on the outer periphery of the container mouth from below, a protruding portion protruding inward of the tamper evident band is provided on an inner peripheral side of the tamper evident band so as to be continuous with an upper portion of the hooks, and an abutting portion is provided on a lower portion of the protruding portion, the abutting portion extending from an inner peripheral surface of the protruding portion toward an upper surface of the hooks so that an inner diameter thereof is reduced at a gradient of 20 degrees or more (claim 1).

The synthetic resin cap may have a projection above the projection on the inner peripheral side of the tamper band, the projection projecting inward of the tamper band from the projection and contacting the outer peripheral surface of the container mouth (claim 2).

Effects of the invention

In the present invention, a synthetic resin cap which is excellent in tamper-evident property and can suppress an increase in cap opening torque can be obtained.

That is, in the synthetic resin cap according to the invention of each aspect of the present application, when the cap attached to the container mouth portion is opened, the abutting portion is brought into abutment with the outer peripheral surface of the annular projection of the container mouth portion in advance, so that the cap can be prevented from being lifted up obliquely, and the annular weakened portion is broken substantially uniformly without being deflected, and therefore, the tamper-evident property is good.

Further, the inner peripheral surface of the abutting portion is provided with a slope of 20 degrees or more, the slope exerts an adjusting function of the abutting degree of the abutting portion with respect to the annular projection, and the abutting portion and the annular projection can be easily configured to favorably abut at the time of unsealing regardless of whether the gap between the protruding portion and the annular projection in the closed state is large or small, and can prevent dropping or an increase in uncapping torque.

In the synthetic resin cap according to the invention of claim 2, the projection abuts against the annular projection when unsealing, so that the cap is prevented from being loosened or inclined, and the effect of preventing the cap from coming off is further improved.

Drawings

Fig. 1 is a longitudinal sectional view schematically showing the structure of a synthetic resin cap according to an embodiment of the present invention.

Fig. 2(a) and (B) are explanatory views schematically showing the configuration of the main part of the synthetic resin cap in the unsealing process.

Fig. 3 is an explanatory view schematically showing a configuration of a main part of a modified example of the synthetic resin cover.

Detailed Description

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 fig. 1 is used by being attached to a mouth of a container (not shown), such as a PET bottle, and is integrally molded from polyethylene by compression molding or injection molding. The material for forming the cap 1 is not particularly limited, and polypropylene or the like is suitably used in addition to the polyethylene used in the present embodiment.

The cap 1 has a top wall 2 that is substantially circular in plan view, and a substantially cylindrical skirt wall 3 that extends downward from the outer periphery of the top wall 2. Here, the skirt wall 3 is provided with a knurled groove 4 on the outer peripheral surface and a female screw 5 on the inner peripheral surface, and the female screw 5 can be coupled to a male screw (not shown) formed on the outer periphery of the container mouth.

The cap 1 is a tamper-proof cap having a function of proving that the cap is not opened (the cap is not opened once), and a tamper-evident band (hereinafter simply referred to as "band") 7 is connected to a lower portion of the skirt wall 3 via an annular weakened portion 6 extending along the entire circumference of the skirt wall 3.

That is, the annular weakened portion 6 vertically divides the skirt wall 3 and the band 7, and is formed of slits (slit-like slits) intermittently extending in the circumferential direction of the skirt wall 3 and the band 7 and connecting bridges existing between the adjacent slits, and the connecting bridges are broken when stretched with a predetermined force.

A plurality of (for example, 5) hooks 8 are provided at intervals in the circumferential direction on the inner circumferential side of the belt 7, and the hooks 8 are configured to protrude inward so that the amount of protrusion inward increases toward the upper side. In a state where the cap 1 is attached to the container mouth, each hook 8 is positioned substantially below an annular projection (protruding portion) 9 (see fig. 2 a and 2B) formed below the male screw on the outer periphery of the container mouth, and is engaged with the annular projection 9 by an unsealing operation. That is, the hook 8 is configured to be engageable with the annular projection 9 from below.

As shown in fig. 2(a), a projecting portion 10 projecting inward of the belt 7 is continuous with the upper portion of the hook 8 on the inner peripheral side of the belt 7, and an abutting portion 11 abutting against the outer peripheral surface of the annular projection 9 is provided at the lower portion of the projecting portion 10. The vertical width L11 of the contact portion 11 is preferably one-third to two-thirds, in this example, of the vertical width L10 of the entire protrusion 10 including the contact portion 11 (L10 is 1.17mm, and L11 is 0.58 mm).

The contact portion 11 extends from the inner peripheral surface of the protruding portion 10 toward the upper surface of the hook 8 such that the inner diameter decreases at a gradient θ of 20 degrees or more (preferably 20 degrees to 30 degrees). If the slope θ is less than 20 degrees, the function of adjusting the degree of abutment of the abutment portion 11 against the annular projection 9 is reduced, and when the gap between the projection 10 and the annular projection 9 in the closed state is relatively large, the abutment portion 11 and the annular projection 9 do not abut well and become loose during unsealing, and the lid 1 may be inclined and fall off; on the other hand, when the gap between the protruding portion 10 and the annular protrusion 9 in the closed cap state is relatively small, the abutting portion 11 strongly abuts against the annular protrusion 9, and the torque required to unseal the cap 1 may be excessively large.

In the cap 1 including the above-described configuration, when the cap 1 is attached to the container mouth portion and is not unsealed, the annular protrusion 9 is positioned inside or above the protrusion 10 (at the position shown in fig. 2 a or above the protrusion), and when the cap 1 is rotated in the unsealing direction from this state, the cap 1 is relatively raised with respect to the container mouth portion, and as shown in fig. 2B, the abutting portion 11 eventually abuts against the annular protrusion 9, and the hook 8 is locked to the annular protrusion 9 from below. When the cap 1 attached to the container mouth is unsealed by further rotating the cap 1 in the unsealing direction, the abutting portion 10 provided to each hook 8 abuts against the outer peripheral surface of the annular projection 9 of the container mouth, whereby the cap 1 can be prevented from being lifted up obliquely, and the annular weakened portion is broken substantially uniformly without being deflected, and therefore, the tamper-evident property is good. In fig. 2(B), the hook 8 engaged with the annular protrusion 9 is drawn so as to overlap the annular protrusion 9, but actually, the two solid bodies do not overlap each other, and the cap 1 side is mainly urged by the container mouth portion to be elastically deformed outward, and the illustration of the elastically deformed portion is omitted.

Further, as described above, the slope θ of 20 degrees or more is provided on the inner peripheral surface of the abutting portion 11, and this slope exerts an adjusting function of the degree of abutment of the abutting portion 11 with respect to the annular projection 9, and the abutting portion 11 and the annular projection 9 can be easily configured to favorably abut at the time of unsealing regardless of whether the gap between the protruding portion 10 and the annular projection 9 in the closed state is large or small, and can prevent dropping or an increase in uncapping torque.

The present invention is not limited to the above embodiments, and it is needless to say that various modifications can be made without departing from the scope of the present invention. For example, the following modifications are possible.

In the above embodiment, the protruding portion 10 and the abutting portion 11 are provided corresponding to each hook 8, but the present invention is not limited to this, and at least one of the protruding portion 10 and the abutting portion 11 may be provided continuously for one turn in the circumferential direction of the belt 7.

The slopes θ of the respective contact portions 11 may be uniform or may be varied, and for example, three contact portions 11 having a slope θ of 20 degrees may be provided, and two contact portions 11 having a slope θ of 30 degrees may be provided.

As shown in fig. 3, a projection 12 may be provided on the inner peripheral side of the band 7 at a position above the projecting portion 10 and below the annular weakened portion 6, and the projection 12 may project inward of the band 7 from the projecting portion 10 and may be in contact with the outer peripheral surface of the container mouth (annular projection 9) in a state where the cap 1 is attached to the container mouth. The projections 12 may be provided over the entire circumference of the belt 7 in the circumferential direction, or a plurality of projections may be provided at intervals in the circumferential direction of the belt 7, and in the latter case, for example, it is considered that one or more projections 12 are provided directly above the hooks 8 in correspondence with the hooks 8. Further, by providing such a projection 12, the projection 12 comes into contact with the annular projection 9 at the time of unsealing, so that the looseness or inclination of the lid 1 can be prevented, and the effect of preventing the detachment of the lid 1 can be further enhanced.

It is needless to say that the above modifications may be combined with each other as appropriate.

Description of the symbols

1 cover

2 roof wall

3 skirt wall

4 knurling groove

5 internal screw thread

6 annular weakened portion

7 belt

8 hook

9 annular protrusion

10 projection

11 abutting part

12 protrusion

Theta gradient

Claims (2)

1. A cap comprising a skirt wall provided with a female screw to be screwed with a male screw formed on the outer periphery of a container mouth, and a tamper evident band connected to the lower part of the skirt wall by an annular weakened portion, characterized in that,

a plurality of hooks are provided on the inner peripheral side of the tamper evident band at intervals in the circumferential direction, the hooks being capable of being engaged with annular projections provided on the outer periphery of the container mouth from below,

further, a protruding portion protruding inward of the tamper band is connected to an upper portion of the hook on an inner peripheral side of the tamper band, and an abutting portion extending from an inner peripheral surface of the protruding portion toward an upper surface of the hook so that an inner diameter thereof is reduced at a gradient of 20 degrees or more is provided on a lower portion of the protruding portion.

2. The synthetic resin cap according to claim 1, wherein a projection is provided above the projection on an inner peripheral side of the tamper evident band, and the projection projects inward of the tamper evident band from the projection and contacts an outer peripheral surface of the container mouth.