JP5249984B2 - cap - Google Patents

Description

  The present invention is, for example, attached to a mouth portion of a container for storing various beverages (with or without carbon dioxide gas, with or without alcohol, with or without fruit juice), and has heat resistance provided with a cap body and packing. Or a cap having a two-piece structure having heat resistance and pressure resistance (heat resistance and pressure resistance).

  As a conventional two-piece structure cap, for example, in Patent Document 1, by setting the rigidity of the packing to be low, a middle leg provided on the packing by internal pressure in a state where the cap is mounted on the container mouth portion is provided inside the container mouth portion. A cap that can ensure high airtightness by being pressed and deformed against the peripheral surface is described.

  In Patent Document 2, an outer seal portion is provided on the top plate of the packing along the outer peripheral edge portion, and an inner seal portion is provided on the inner side of the outer seal portion. There is described a cap capable of maintaining an airtight state of a container by fitting to the outer periphery of the container mouth part and fitting an inner seal part into the container mouth part.

  However, the cap described in any of the above patent documents adopts a shape that ensures the airtightness inside the container by bringing the entire outer peripheral surface of the middle foot into close contact with the inner peripheral surface of the container. When mounting, there was a problem that the middle foot slidably contacted with the inner peripheral surface of the container mouth portion, and it was difficult to wind the cap, resulting in poor tightening.

  In addition, caps (heat-resistant pressure caps) for carbonated beverages containing fruit juice sterilize the liquid contents with a hot water shower after filling the container with the beverage and attaching the cap, but not only the container but also the cap body and packing become hot. By applying internal pressure to the container where deformation is likely to occur, a phenomenon occurs in which the top wall of the cap body and the center of the top plate of the packing swell (a doming phenomenon). When the doming phenomenon occurs, there is a problem that the airtightness is deteriorated, or the top plate of the packing is pressed against the top wall of the cap body to be in close contact, and it is easy to rotate together at the time of opening.

JP-A-11-180459 JP-A-8-324610

  The present invention has been made in view of the above-described conventional problems. When the cap is attached to the container, the cap can be easily wound around the container, and the cap attached to the container is kept airtight. It is an object of the present invention to provide a cap that prevents the cap body and the packing from rotating together when the cap is opened.

In order to solve the above-mentioned problem, a cap according to the present invention has a top wall and a side wall depending from the outer peripheral edge of the top wall, and a female screw that is screwed into a male screw of the container mouth is formed on the side wall. A cap body and a packing that is fitted inside the cap body and seals the container mouth, and the packing engages with the top wall and abuts and covers the tip of the container mouth. In a cap having a plate and an annular middle leg that hangs down from the top plate and adheres closely to the inner peripheral surface of the container mouth,
On the engagement surface between the top wall and the top plate, only the bottom surface of the top wall, only the top surface of the top plate, or both the bottom surface of the top wall and the top surface of the top plate are textured. Provided,
The outer peripheral edge of the top plate of the packing is bent downward with respect to the top plate, and an annular bent portion whose inner peripheral surface is in contact with the outer peripheral surface of the container mouth portion is continuously provided,
The cap body is provided with a reduced diameter portion that is continuous with a bulging portion that is provided at the base of the middle foot and is in close contact with the inner circumferential surface of the container mouth, and that curves inward in the radial direction. When the is attached to the container mouth portion, an interval occurs between the inner peripheral surface of the container mouth portion and the outer peripheral surface of the middle foot,
In the vicinity of the boundary between the top wall and the side wall, an annular urging portion that protrudes inward obliquely downward is formed.

  With the above configuration, it is possible to prevent the cap main body and the packing from coming into close contact with each other in a state where the cap is attached to the container mouth. Therefore, even if the cap body is rotated to open the cap from the state in which the cap is attached to the container mouth portion, it is possible to prevent the packing from rotating together with the cap body and to prevent the container contents at the moment the cap body is rotated. It is possible to prevent air from escaping.

By providing the bent portions continuously , high adhesion can be obtained with the cap mounted on the container.

By providing the reduced diameter portion , a gap is formed between the inner peripheral surface of the container mouth portion and the outer peripheral surface of the middle foot when the cap is attached to the container mouth portion, so that the contact area is small and the frictional force is small. As a result, the cap can be easily wound around the container mouth.

More the reduced diameter portion is continuous with the bulge portion, even if the spacing between the inner surface and the reduced diameter portion of the container mouth portion in a state of mounting the cap on the container, the bulging portion the container opening It is possible to prevent the contents from leaking out of the container by ensuring close contact with the inner peripheral surface of the container and ensuring high airtightness.

  In addition, even if a doming phenomenon occurs, the middle leg of the packing is pressed against the container mouth by deformation of the reduced diameter portion, so that the bulging portion is kept in close contact with the inner peripheral surface of the container mouth, and the inside of the bent portion is maintained. Since the peripheral surface is in contact with the outer peripheral surface of the container mouth portion, high airtightness can be ensured. Even if the packing top plate presses against the top wall of the cap body due to the doming phenomenon, the cap body and the packing are It is possible to prevent co-rotation at the time of opening without close contact.

  According to the present invention, by providing a matte-like unevenness on the engagement surface between the top wall and the top plate, even if the cap body is rotated, the packing is prevented from rotating simultaneously with the cap body, and the cap body is rotated. It is possible to prevent the air in the container contents from being released at the moment of opening.

  In addition, by providing a reduced diameter part on the middle leg of the packing, a gap is created between the inner peripheral surface of the container and the middle leg, resulting in a smaller contact area and less frictional force. As a result, the cap is attached to the container mouth. When doing so, the cap can be easily wound around the container mouth.

(A) is a perspective view of the cap by embodiment of this invention, (B) is a perspective view which shows schematically the structure of the principal part of the container by embodiment of this invention. It is a semi-longitudinal sectional view which shows the state which closed the cap of FIG. 1 to the container. It is an expanded sectional view of the engaging surface between the cap main body and packing of FIG. FIG. 3 is a semi-longitudinal sectional view schematically showing a configuration of packing of the cap of FIG. 2.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  As shown in FIGS. 1 (A) and 1 (B), a cap 11 according to this embodiment is attached to a mouth portion 22 of a container (for example, a plastic bottle) 21 manufactured separately from the cap 1. Yes, it is molded by injection molding or compression molding.

  On the other hand, the content stored in the container 21 is, for example, a carbonated beverage containing fruit juice. However, the contents are not limited to carbonated beverages containing fruit juice, but may be other alcoholic beverages (for example, wine, sparkling wine), carbonated beverages, soft drinks, and the like.

  As shown in FIG. 2, the cap 11 includes a cap body 12 and a synthetic resin packing 31 that seals the container opening 22. The cap body 12 and the packing 31 are made of synthetic resin with excellent flexibility and low frictional resistance. For example, polypropylene (homo, block, random, etc.) or polyethylene (HD (high density), LL (Linear Base resin consisting of Low Density) and LD (Low Density) is adopted.

  As shown in FIG. 1A and FIG. 2, the cap body 12 includes a circular ceiling wall 13 and a side wall 14 depending from the outer peripheral portion of the ceiling wall 13 in plan view. On the lower surface 13 a of the top wall 13, a projection 13 b is formed that protrudes toward the distal end portion 24 of the container mouth portion 22 described later. Thereby, in a state where the cap 11 is attached to the container 21, the protrusion 13 b presses the packing 31 against the distal end portion 24, thereby improving the sealing performance of the container mouth portion 22. However, as long as the sealing property of the container mouth portion 22 can be ensured, a configuration in which the protrusion 13b is not provided may be employed.

  In the vicinity of the boundary between the top wall 13 and the side wall 14, an annular urging portion 16 that protrudes inward obliquely downward is formed. A knurled groove 17 is provided on the outer peripheral surface of the side wall 14, and a female screw 18 is provided on the inner peripheral surface, so that the female screw 18 is screwed into the male screw 23 of the container mouth portion 22.

  On the other hand, as shown in FIGS. 2 and 4, the packing 31 is suspended from the top plate 32, and a substantially disk-shaped top plate 32 that contacts and covers the tip portion 24 of the container mouth portion 22. An annular (substantially cylindrical) middle leg 33 that is partially in close contact with the inner peripheral surface 26 of the container mouth portion 22 is provided concentrically. Further, an annular bent portion 34 that is bent downward with respect to the top plate 32 and whose inner peripheral surface abuts on the outer peripheral surface 27 of the container mouth portion 22 is connected to the outer peripheral edge of the top plate 32. .

  The packing 31 is fitted inside the cap body 12. That is, the outer diameter of the packing 31 is larger than the inner diameter of the crest of the female screw 18 of the cap body 12 and smaller than the inner diameter of the trough, and the peripheral edge of the packing 31 is located above the female screw 18 of the cap main body 12. It is configured to lock.

  The upper surface 32a of the top plate 32 constituting the engagement surface between the top wall 13 of the cap body 12 and the top plate 32 of the packing 31 according to the present invention is formed with a satin-like unevenness as a whole as shown in FIG. Has been. On the other hand, the lower surface 13a of the top wall 13 is formed flat. As a result, the cap body 12 and the packing 31 are not in close contact with the cap 11 attached to the container 21. Here, the surface roughness (ten-point average roughness) Rz of the upper surface 32a is preferably 6.0 to 25.0 μm.

  Further, in the present embodiment, the textured unevenness is formed on the upper surface 32a of the top plate 32. However, for example, the unevenness is formed on the lower surface 13a of the top wall 13, and the upper surface 32a of the top plate 32 is formed flat. Also good. Furthermore, the same effect can be obtained even if a configuration in which the unevenness is formed on both the lower surface 13a of the top wall 13 and the upper surface 32a of the top plate 32 is employed.

  As shown in FIG. 4, on the outer peripheral surface of the middle foot 33, a reduced diameter portion 38 that is continuous with the top plate 32 and constitutes the root 37 of the middle foot 33, and from this reduced diameter portion 38 in the opposite direction to the top plate 32. A continuous bulging portion 39 is formed.

  The reduced diameter portion 38 is curved inward in the radial direction so that a predetermined interval L1 (see FIG. 2) occurs between the inner diameter surface 26 of the container 21. Specifically, here, the inner radius L2 of the inner peripheral surface 26 of the container 21 is 10.3 mm, whereas the radius L3 of the reduced diameter portion 38 is 10.25 mm to 10.275 mm. Yes. Accordingly, an interval L1 of 0.025 mm to 0.05 mm is generated between the inner peripheral surface 26 of the container 21 and the reduced diameter portion 38.

  The bulging portion 39 is continuous with the reduced diameter portion 38 so that the outer diameter increases toward the maximum diameter portion 42 below and the outer diameter decreases from the maximum diameter portion 42 toward the tip 43 below. It is configured. In a state in which the cap 11 is attached to the container 21, the maximum diameter portion 42 abuts most strongly against the inner peripheral surface 26 of the container mouth portion 22.

  Next, the mounting operation of the cap 11 on the container mouth portion 22 will be described.

  In order to attach the cap 11 to the container mouth portion 22, the internal thread 18 of the cap body 12 is screwed to the external thread 23 of the container mouth portion 22, and then the cap body 12 is attached to the cap body 12 in the direction of arrow S in FIG. Apply the rotational force. At this time, by forming the reduced diameter portion 38 in the middle leg 33 of the packing 31, there is a gap L1 between the inner peripheral surface 26 of the container 21 and the middle leg 33, and the contact area is small and the frictional force is small. The cap 11 can be easily wound around the container opening 22. This also prevents the occurrence of poor winding. Then, the cap body 12 is screwed downward in FIG.

  In this mounted state (capped state), the bulging portion 39 that is a part of the middle leg 33 of the packing 31 is in close contact with the inner peripheral surface 26 of the container mouth portion 22 (see FIG. 2). As a result, even when the reduced diameter portion 38 is disposed at a predetermined distance L1 from the inner peripheral surface 26 of the container mouth portion 22 in the mounted state, it ensures high airtightness and prevents the contents from leaking out of the container 21. can do.

  Further, the flange portion 36 between the middle leg 33 and the bent portion 34 of the packing 31 is in close contact with the tip portion (tip surface) 24 of the container mouth portion 22, and the bent portion 34 of the packing 31 is the urging portion 16. Is pressed against the outer peripheral surface 27 of the container mouth portion 22. Here, the cap 11 in a state of being attached to the container mouth portion 22 is in a state in which the middle foot 33 contacting the inner peripheral surface 26 of the container mouth portion 22 is elastically deformed radially inward.

  And it opens by applying the rotational force of the arrow O direction of FIG. 1 (A) with respect to the cap main body 12 of the cap 11 with which the container opening part 22 was mounted | worn. At this time, a satin-like unevenness is formed on the upper surface 32 a of the top plate 32 to prevent the lower surface 13 a of the top wall 13 and the upper surface 32 a of the top plate 32 from coming into close contact with each other. Therefore, even if the cap body 12 is rotated, the co-rotation of the cap body 12 and the packing 31 rotating simultaneously is prevented, and the air in the container contents is prevented from being released at the moment when the cap body 12 is rotated and opened. Can do.

  Further, when the cap body 12 is rotated, the internal thread 18 of the cap body 12 and the external thread 23 of the container 21 are in sliding contact, and the cap body 12 is screwed upward. On the other hand, the packing 31 remains in close contact with the container opening 22. When the cap body 12 continues to rotate, the uppermost female screw 18 comes into contact with the bent portion 34 of the packing 31 and pushes up, so that the cap body 12 is screwed upward together with the packing 31. When the sliding contact between the female screw 18 and the male screw 23 is completed, the cap main body 12 is unscrewed from the container 21 together with the packing 31.

DESCRIPTION OF SYMBOLS 11 Cap 12 Cap main body 13 Top wall 14 Side wall 18 Female screw 22 Container mouth part 23 Male screw 31 Packing 32 Top plate 33 Middle leg 34 Bending part 38 Reduced diameter part 39 Expansion part

Claims (1)

A cap body having a top wall and a side wall depending from the outer peripheral edge of the top wall, and a female screw threadedly engaged with the male screw of the container mouth portion is fitted into the cap main body; A packing for sealing the container mouth, and the packing engages with the top wall and covers the top of the container mouth in contact with the top, and hangs down from the top and hangs from the top of the container mouth. In a cap having an annular middle leg that is in close contact with the inner peripheral surface,
On the engagement surface between the top wall and the top plate, only the bottom surface of the top wall, only the top surface of the top plate, or both the bottom surface of the top wall and the top surface of the top plate are textured. Provided,
The outer peripheral edge of the top plate of the packing is bent downward with respect to the top plate, and an annular bent portion whose inner peripheral surface is in contact with the outer peripheral surface of the container mouth portion is continuously provided,
The cap body is provided with a reduced diameter portion that is continuous with a bulging portion that is provided at the base of the middle foot and is in close contact with the inner circumferential surface of the container mouth, and that curves inward in the radial direction. When the is attached to the container mouth portion, an interval occurs between the inner peripheral surface of the container mouth portion and the outer peripheral surface of the middle foot,
In the vicinity of the boundary between the top wall and the side wall, an annular urging portion projecting inward obliquely downward is formed.

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