JPS5844555B2 - Cap and method for sealing the mouth of a container using it - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cap and a method of sealing a container opening using the same.

Conventionally, when sealing the container mouth by screwing a non-metallic cap onto the mouth of a synthetic resin container, various structures have been introduced to maintain the sealing performance that is the mission of the container, and to solve this problem. Although the sealability is maintained, the problem of making it easier to open the cap after sealing has not yet been solved.

For example, as shown in FIG.
A thin film 6 having a discharge port C made of substantially the same material as the container body 1 as shown in FIG.
A thin plate 7 made of metal such as aluminum is placed on top of the first
A cap 10 having a screw 8 on its inner circumferential surface to be screwed into the male thread 3 as shown in FIG. By passing the container body 1 under the high-frequency induction heating device in this state, even if the end surface of the flange portion 4 is uneven, the pressing force of the small projections 9 against the flange portion 4 and the constriction can be reduced. In some cases, the thin film 6 is flatly welded to the flange portion 4 by utilizing the compressive deformation of the thin film 6 without causing wrinkles or cuts on the periphery of the thin film 6 to ensure the sealing performance of the container mouth portion 2 (Japanese Patent Application Laid-Open No. 55-11843).

However, in this case, when the container body 1 is heated by high-frequency induction, the ring-shaped small protrusion 9 provided on the medial malleolus surface 10' of the cap 10 is formed on the end surface of the flange portion 4, such as at the joint of the split mold during container molding. Even if some remains, press it to prevent the occurrence of wrinkles caused by seams, etc., and also to prevent the medial malleolus surface 10' of the cap 10 and the flange portion 4 from forming, albeit through the thin film 6 and the thin plate 7. Although the contact is made so good that the sealing property is reliably maintained, the ring-shaped small protrusion 9 is formed between the medial malleolus surface 10' and the thin plate 7 due to the heat generated by the thin plate 7, as shown in FIG. The wide-range area dog is melted and passed through the thin film 6 welded to the 7-run part 4 at the mouth of the container to create a temporary seal by passing the thin plate 7 over a wide area and creating a temporary seal, which requires a large torque to open the cap after sealing. There is a drawback that.

The present invention solves the above-mentioned drawbacks, makes it easier to open the cap after sealing, and has a cap that does not affect the sealing performance of the container mouth even if it is made easy to open, and a method for sealing the container mouth using the cap. The gist of the invention is to provide a non-metallic cap that is screwed into a threaded opening of a synthetic resin container opening, and a flange provided at the container opening. A small ring-shaped protrusion is provided on the corresponding inner top surface, and an annular groove is provided on the inside and outside of the small protrusion, and a constricted part and a tapered part are provided at the opening for threading of the synthetic resin container opening. A flange portion is provided, a thin film made of substantially the same material as the container is placed on the flange portion, and a thin metal plate is placed on the thin film, while inner and outer surfaces are provided on the inner top surface corresponding to the flange portion. The thin film is welded to the container mouth by high-frequency induction heating with a non-metallic cap provided with a ring-shaped small protrusion having an annular groove screwed onto the container mouth. do.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a cap according to the present invention and a method for sealing a container opening using the same will be explained based on embodiments shown in the drawings.

The features of the cap according to the present invention are as shown in FIG.
Inner top surface 10 corresponding to the seven rungs 4 of the cap 10
' is provided with a small protrusion 9 having an annular groove 11 on the inside and outside.

The sealing method and the structure of the container opening are the same as the conventional example explained in FIG.
Since the annular groove 11 is provided on the inside and outside of the
When the container body 1 is heated by high frequency induction, even if the ring-shaped small protrusion 9 provided on the inner top surface 10' of the cap 10 melts due to the heat generated by the thin plate 7, the melted portion will be the small protrusion 9.
Since it enters the annular groove 11 provided on the inside and outside of the film and does not diffuse between the inner top surface 10' and the thin plate 7, the area of the temporary sealing part 12 where the thin film 6 and the thin plate 7 are in close contact is small. Easy to use, no large torque is required to open the cap after it is sealed.

As described above based on the embodiments shown in the drawings, according to the cap and the method for sealing a container mouth using the same according to the present invention, the cap corresponding to the flange provided at the container mouth can be Since the inner top surface has a small ring-shaped protrusion and an annular groove on the inside and outside of the small protrusion, the molten part of the small protrusion does not spread between the inner top surface of the cap and the thin plate and enters the annular groove, preventing the temporary sealing area. The area of the cap becomes smaller, making it easier to open the cap after sealing, and even if it becomes easier to open, the tapered flange part will not move upward during high-frequency induction heating due to the repulsive action of the constriction part created in response to the upward force on the threads of the container opening. The thin film and flange can be welded together after being pushed up to a flat state.Furthermore, due to the pressure of the small protrusions against the flange, the thin film can be welded even if there are unevenness or alignment on the end surface of the flange. High sealing performance can be ensured without wrinkles or cuts.

[Brief explanation of the drawing]

FIG. 1A is a partially fragmented front view of the container opening, FIG. 1B is a sectional view of the thin film and thin plate, FIG. 1C is a sectional view of a conventional cap, and FIG. 2 is a conventional sealing process. It is a partial sectional view showing the state inside. 3 is an enlarged cross-sectional view of the protruding portion of the cap according to the present invention, FIG. 4A is a partial cross-sectional view showing the state during the sealing process of the present invention, and FIG. 4B is the X of FIG. 4A. It is an enlarged view of the part. In the drawings, 1 is the container body, 2 is the container mouth, 3 is the male thread, 4 is the flange, 5 is the constriction, 6 is the thin film, 6' is the discharge port, and 7
is a thin plate, 8 is a female thread, 9 is a protrusion, 10 is a cap, 10
' is an inner top surface, 11 is an annular groove, and 12 is a temporary sealing portion.

Claims (1)

[Scope of Claims] 1. In a non-metallic cap that is screwed into a threaded opening of a synthetic resin container mouth, a small ring-shaped cap is provided on the medial malleolus surface corresponding to the flange provided on the container mouth. 1. A cap characterized in that a projection is provided and an annular groove is provided on the inside and outside of the small projection. 2 A constriction part and a tape-shaped flange part are provided at the threaded opening of the synthetic resin container opening, and a thin film made of substantially the same material as the container is placed on the flange part, and a thin film made of substantially the same material as the container is placed on the flange part. A thin metal plate is placed on the container, while a non-metallic cap having a small ring-shaped protrusion having annular grooves on the inside and outside on the medial malleolus surface corresponding to the flange portion is screwed onto the container mouth portion. A method for sealing a container mouth, characterized in that the thin film is welded to the container mouth by high-frequency induction heating.