JPH0420726Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention relates to the mouth of a metal container, and more specifically, to prevent a synthetic resin cylindrical body attached to the mouth of a metal container from rotating around the mouth. This relates to the opening of a metal container that is prevented from rotating.

BACKGROUND ART Conventionally, a cylindrical body made of synthetic resin is attached to the cylindrical mouth of a metal container made of aluminum, etc., and a cap (not shown) is screwed into the male thread of this cylindrical body. Some have their mouths closed. A curled portion that is curved radially outward in an elliptical shape is usually formed at the tip of the opening of such a metal container, and this curled portion is locked to the tip of the cylindrical body.

However, in such metal containers, the curled part is only locked to the tip of the cylindrical body, so when the cap is tightened, the cylindrical body becomes one with the cap and wraps around the mouth. There was a drawback that the cylindrical body rotated, and it was necessary to prevent the cylindrical body from rotating.

An example of a mouth portion of a metal container in which the rotation of the cylindrical body is prevented is shown in FIG. 6, for example. In FIG. 6, 50 is a protrusion. The width of the protrusion 50 is about 4 mm to 6 mm, and the cylindrical body 51 that fits into the protrusion 50 has a groove 52 in the axial direction.
It is formed with the same width as the width of. Usually, after fitting the cylindrical body 51 into the mouth 54 of the metal container 53, a protrusion process is performed from the inner surface of the mouth 54 to form a protrusion 50 on the outer peripheral surface of the mouth 54.
was fitted into a groove 52 formed in the cylindrical body 51 to prevent rotation. In some cases, the protrusions 50 are formed on the outer periphery of the metal container 53 by protrusion processing before the cylindrical body 51 is attached. In this case, when the cylindrical body 51 is attached to the mouth portion 54, the protrusion 50 is fitted into the groove 52 to prevent the cylindrical body 51 from rotating. Furthermore, the opening 5 of the metal container 53 protrudes from the upper part of the cylindrical body 51.
4 is formed with an elliptical curl portion 55 that is curved outward in the radial direction.
1 from the outer periphery of the mouth portion 54.

Problems that the invention attempts to solve However, such conventional metal containers 53
In the case of the mouth part 54 of the metal container 5, the cylindrical body 51 is
When the rotation is to be prevented after the insertion into the opening 54 of No. 3, the protrusion 50 is formed by protruding outward from the inner surface of the opening 54. The disadvantage was that the contents could be damaged and the contents deteriorated due to corrosion of the metal in the damaged area.
In addition, if the projection 50 is to be formed in the mouth 54 of the metal container 53 before the cylindrical body 51 is attached to the mouth 54 of the metal container 53, the projection 50 is usually formed after the impact molding of the metal container 53 is performed. 50, the work process was two-step, an impact molding process and an ejection process, which was a time-consuming process.
Furthermore, in the case of forming such a protrusion 50, since the conventional protrusion 50 and groove 52 have a large width and a small number, the cylindrical body 51 is
When inserting the cylindrical body 51 into the
It is necessary to align the projections 50 and the grooves 52, and when there are many containers 53 to be assembled,
There was a problem in that it took time to attach the cylindrical body 51.

Therefore, this idea was developed to eliminate damage to the inner coating film of the mouth part due to protrusion processing, and to have a metal container cap attachment mechanism that requires fewer work steps and allows for smooth insertion of a cylindrical body with protrusions into the mouth part. The purpose is to provide

Means for Solving the Problem In order to achieve this objective, the metal container cap attachment mechanism of this invention has an inner diameter approximately equal to the outer diameter of the mouth of the metal container, and a male thread is formed on the outer peripheral surface. and a cylindrical body made of synthetic resin in which many thin vertical grooves are densely formed in the axial direction from the approximate center of the inner circumferential surface downward, and from the approximate center downward of the outer circumferential surface thereof. and a mouth of a metal container in which a plurality of vertical protrusions are formed to fit into the longitudinal grooves and prevent rotation of the cylindrical body, and at the tip of the mouth of the metal container, It is characterized by the formation of a curled portion that curves outward in the radial direction.

Function of the device The function of this device, which has the above structure, will be explained. For example, as shown in FIGS. 2 and 3, the cylindrical body 3 is inserted into the mouth portion 2 from above. At this time, the vertical protrusions 2b fit into the grooves 4, and rotation of the cylindrical body 3 is completely prevented. Since both the longitudinal protrusions 2b and the grooves 4 have a narrow width of about 0.2 mm to 0.8 mm, the longitudinal protrusions 2b can be smoothly fitted into any of the grooves 4. Therefore, the trouble of attaching the cylindrical body 3 to the mouth part 2 while aligning the protrusions and grooves as in the conventional case can be saved. Note that the curled portion 5 formed by radially curving the mouth tip 2a of the mouth portion 2 is locked to the tip of the cylindrical body 3, so that the cylindrical body 3 is attached to the mouth portion of the metal container 1. There will be no departure from 2.

Example Next, this invention will be explained based on the drawings.

1 to 5 are drawings showing an embodiment of this invention. In the figure, 3 is a cylindrical body made of synthetic resin such as polyethylene terephthalate. A male thread 3a is provided on the outer peripheral surface of the cylindrical body 3 except for the lower part.
is formed. Further, the inner peripheral surface of the cylindrical body 3 is a cylindrical surface, and is inserted into the outer peripheral surface of the mouth portion 2 of the metal container 1 in a tight state. A chamfered portion 3c is formed inside the lower end portion 3b so that the lower end portion 3b of the cylindrical body 3 comes into close contact with the mold horizontal portion 1a of the metal container 1. A large number of thin longitudinal grooves 4 are formed in the axial direction from the approximate center of the inner peripheral surface of the cylindrical body 3 downward. The width of this narrow vertical groove 4 is
It is about 0.2mm to 0.8mm, and in the example it is from 50 pieces.
Approximately 100 of them are formed in a range that goes around the inner peripheral surface. The number of vertical grooves 4 can be set arbitrarily. On the other hand, the metal container 1 into which this cylindrical body 3 is inserted is made from aluminum slag by impact molding. On the outer periphery of the mouth portion 2 of the metal container 1, a thin vertical protrusion 2b that fits into the vertical groove 4 is formed from approximately the center downward. In the embodiment shown in FIG. 2, eight vertical protrusions 2b are formed,
In the embodiment shown in FIG. 3, about 80 to 100 vertical protrusions 2b are formed, but the number of vertical protrusions 2b can also be set arbitrarily. Note that the vertical grooves 4 formed on the inner peripheral surface of the cylindrical body 3 are formed by molding simultaneously with the molding of the cylindrical body 3, and the vertical grooves 4 formed on the outer periphery of the mouth part 2 of the metal container 1. 2b is formed by impact molding and simultaneous molding of the metal container 1, or by press-contacting a rolling piece (not shown) to the outer periphery of the mouth portion 2 at the same time as the impact molding. The vertical ridges 2b shown in FIG. 2 are an example in which they are formed by impact molding and simultaneous molding, and in this case, as shown in FIG. 4 is fitted. The vertical protruding strip 2b shown in FIG. 3 is an example in which it is formed by pressing a rolling piece to the outer periphery of the mouth part 2 by impact molding and simultaneous molding. As shown, all the vertical protrusions 2b and the vertical grooves 4 fit together. After the cylindrical body 3 is attached to the mouth of the metal container 1, the tip 2a of the mouth 2 is bent radially outward to form a curled portion 5. This curled portion 5 is locked to the tip of the cylindrical body 3 and prevents the cylindrical body 3 from slipping out from the mouth portion 2.

Effects of the invention As explained above, according to the metal container cap attachment mechanism of this invention, after the cylindrical body is attached to the mouth of the metal container as in the conventional case, a rotation-preventing protrusion is inserted from the inner surface of the mouth. Since there is no need to perform protrusion processing to form protrusions, there is no damage to the inner surface coating of the mouth portion due to such processing. Moreover, in this invention, the formation of the vertical protrusions on the outer periphery of the mouth portion is performed simultaneously with impact molding, so the manufacturing process can be completed in one step, and the process can be simplified. Furthermore, since many thin vertical grooves are formed on the inner peripheral surface of the cylindrical body, the vertical protrusions provided on the outer circumference of the mouth part can easily fit into any of the vertical grooves, eliminating the need for alignment. This makes it extremely easy to attach the cylindrical body to the mouth. Furthermore, by forming a curled portion at the tip of the mouth, it is expected that the sealing performance of the mouth will be improved when the cap is screwed together.

[Brief explanation of the drawing]

1 to 5 are drawings showing an embodiment of the cap attachment mechanism for a metal container according to this invention, and FIG. 1 is a longitudinal cross-sectional view when a cylindrical body is attached to the mouth, 2 and 3 are longitudinal sectional views showing the state in which the cylindrical body is attached to the mouth, and FIGS. 4 and 5 are sectional views taken along line A-A in FIG. is a cross-sectional view of FIG. 2 with the cylindrical body attached to the mouth, FIG. 5 is a cross-sectional view of FIG. 3 with the cylindrical body attached to the mouth, and FIG. 6 is the mouth of a conventional metal container. FIG. 6a is a longitudinal cross-sectional view when the cylindrical body is attached to the mouth, and FIG. 6b is a view taken along the line B-B in FIG. 6a.
It is a line enlarged sectional view. DESCRIPTION OF SYMBOLS 1... Metal container, 2... Mouth part, 2a... Mouth tip, 2b... Vertical protrusion, 3... Cylindrical body, 3b... Male screw, 4... Vertical groove, 5... Curl part .

Claims (1)

[Claims for Utility Model Registration] 1. Having an inner diameter approximately equal to the outer diameter of the opening of the metal container, and having a male thread formed on the outer peripheral surface thereof,
A synthetic resin cylindrical body in which a large number of thin vertical grooves are densely formed in the axial direction from the approximate center of the inner circumferential surface downward, and the vertical grooves extend downward from the approximate center of the outer circumferential surface of the synthetic resin cylindrical body. a mouth of a metal container on which a plurality of vertical protrusions are formed to fit into the cylindrical body and prevent rotation of the cylindrical body; A cap attachment mechanism for metal containers that is formed with a curled portion. 2. Cap mounting of a metal container according to claim 1, wherein the longitudinal groove is formed in the inner circumferential surface of the cylindrical body in a range that goes around the inner circumferential surface once. mechanism.