JP2939898B2 - Method for producing cap for carbonated beverage bottle and cap for carbonated beverage bottle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing caps for ramune bottles and other caps for carbonated beverage bottles.

[0002]

2. Description of the Related Art Conventionally, a synthetic resin cap for sealing a ramune bottle has been known. This cap is a lid in which the outer plug and the inner plug are integrated, the inner surface of the outer plug is engaged with the outer surface of the ramune bottle opening, and the inner plug is inserted into the ramune bottle opening, and the inner surface of the inner plug is The projections provided supported the ramune balls and sealed the bottle mouth.

[0003]

The above-mentioned cap for a ramune bottle is covered with its outer cap over the bottle mouth. At this time, a component having a strength capable of withstanding the internal pressure of carbon dioxide gas,
Appropriate condition settings for the molding are required. For this reason, the outer plug has been formed of a hard plastic material.
The inner stopper cooperated with the outer stopper in the bottle mouth to support the ramune ball so that it did not pop out. On the other hand, when drinking, this ramune ball is pushed down into the bottle, so in order to satisfy these two functions, the inner plug is made of a component having appropriate flexibility, and the appropriate conditions are set during molding. Is required. Therefore, the inner plug has been formed of a plastic material having flexibility.

In order to satisfy the above requirements, it is important to select a constituent material and to manufacture the integrated cap accurately and economically in large quantities without variation by setting appropriate conditions. Further, this cap has a problem that it is necessary to selectively use a hard plastic material having different molding temperatures and flow characteristics and a plastic material having flexibility in accordance with each molding condition. The present invention provides a novel method for producing a cap for a carbonated beverage bottle, which is capable of accurately and economically molding a cap for sealing a bottle of a carbonated beverage such as a ramune beverage with high precision and without variation, and producing the cap using this novel production method. To provide a new cap for carbonated beverage bottles.

[0005]

In order to achieve the above-mentioned object, the method of the present invention comprises inserting a movable mold into a fixed mold provided with a cavity for molding an outer plug. A first step of injecting a synthetic resin into the outer plug to form an outer plug, and transferring the outer plug formed in the first step to another fixed mold having a cavity for forming a cap, and fitting the outer plug therein. Another moving side mold is inserted into the outer plug, a synthetic resin is injected, the inner plug is fused to the upper inner surface of the outer plug, and molded, and the outer plug and the inner plug are integrated into a cap. Is molded.

The outer plug is formed using a hard synthetic resin, and the inner plug is formed using a flexible synthetic resin.
A bottle mouth receiving portion is formed between the outer plug and the inner plug, and the inner plug is molded so that the ramune ball can be hermetically stored in the inner plug.

[0007]

The moving mold is inserted into a fixed mold provided with a cavity for molding an outer cap, a synthetic resin is injected into the cavity to form an outer cap, and a cap is formed. The outer plug formed in the first step is transferred and fitted into another fixed-side mold having a cavity therefor, another moving-side mold is inserted into the outer plug, and synthetic resin is injected. Since the inner plug is fused to the upper inner surface of the outer plug and molded, and the outer plug and the inner plug are integrated to form a cap, the mold used in the first step is made of a hard synthetic resin. The molding temperature and flow conditions suitable for molding can be set, and the mold used for the second step can be set to the molding temperature and flow conditions suitable for molding a flexible synthetic resin. By doing so, the cap can be molded.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for producing a carbonated beverage bottle cap according to the present invention will be described with reference to FIGS. First, the cap 1 for a carbonated beverage bottle formed by the manufacturing method of the present invention will be described with reference to FIG. The cap 1 comprises an outer plug 2 molded using a hard synthetic resin in a first step, and a flexible inner plug 6 fused and molded to an upper inner surface 5 of the outer plug 2 in a second step. It is molded integrally.

The outer plug 2 is formed in a substantially inverted bowl shape. A small circular upper opening is formed at the center of a slightly outwardly curved upper surface 4 by an upper opening edge 3, and a lower portion thereof is formed. Has a long lower opening formed by a lower opening edge 3 '. The inner plug 6 is formed in a cylindrical shape, and upper and lower openings thereof are opposed to an upper opening and a lower opening of the outer plug 2, respectively. The gap between the inner surface of the outer plug 2 and the outer surface of the inner plug 6 is a bottle mouth receiving portion 17. Further, on the inner surface of the inner plug 6, a corner portion 19 orbiting the inner surface and a projection 20 having a V-shaped cross section are formed at an interval. The corners 19 and the projections 20 are for holding the ramune balls in the inner stopper 6 in an airtight manner. The outer plug 2 is molded using a high-density polyethylene resin of a low-pressure polymerization method as a hard synthetic resin,
The inner plug 6 is formed by using an equally mixed resin of a low-density polyethylene resin and a polyolefin-based high-density resin obtained by a high-pressure polymerization method as a flexible synthetic resin. The synthetic resin forming the outer plug and the inner plug is not limited to the above example. For example, a compound having appropriate properties and performance may be used.

FIG. 1 shows a fixed mold 7 and a movable mold 9 used in the first step of molding the outer plug 2. A cavity 8 for molding the outer plug 2 is formed in the fixed mold 7 in a substantially bowl shape, and a small circular projection 13 is provided at the center of the cavity 8. In this fixed mold 7, a cylindrical moving mold 9 penetrates a product protruding plate 10 in contact with the fixed mold 7, and a forming mold 11 at the tip thereof is inserted into the cavity 8. A circular small protrusion 12 </ b> C protruding from the enlarged diameter portion 12 provided at the front end of the molding die 11 is in contact with the front end surface of the small protrusion 13.

The fixed mold 7 is provided with a sprue 14 for injecting the hard synthetic resin into the cavity 8 through the small projection 13. The sprue 14 is provided on the movable mold 9 The tip 16 is formed in an elongated hole shape that penetrates into the enlarged diameter portion 12 of the movable side die 9. The sprue 14 is formed in the opposite direction by connecting the runner gates 21 and 21 to the tip thereof.
The tip end pore is opened at the upper end of the peripheral surface of the small projection 12C of the movable mold 9. The distance between the tip pores of the runner gates 21 corresponds to the diameter of the opening on the upper surface 4 of the outer plug 2.

When the hard synthetic resin is injected from the sprue 14 into the cavity 8 through the runner gate 21 and molded at a predetermined temperature, the outer plug 2 is cooperated with the fixed mold 7 and the movable mold 9 to cooperate. Can be molded. FIG. 3 shows a state in which the outer plug 2 molded as described above is pulled out of the fixed die 7 together with the movable die 9 together with the molded product according to a conventional method. The injection port is pulled out, and the molding of the outer plug 2 is completed.

Next, the outer plug 2 is connected to another stationary mold 22.
The second step of molding the carbonated beverage bottle cap 1 in cooperation with another moving side mold 23 will be described with reference to FIG. A circular projection 13A is provided at the center of the cavity 8 of the fixed mold 22. On the other hand, the moving side mold 2
3 is formed by a cylindrical core sleeve pin 25 penetrating the product projecting plate 10 and a cylindrical core pin 26 inserted through the core sleeve pin 25. FIG.
The inside of the outer plug 2 is fitted with the opening of the upper surface 4 into the above-mentioned projection 13A, and the whole of the outer plug 2 is cavity 8 of the fixed mold 22.
It is fitted in. Therefore, the upper inner surface 5 of the outer plug 2 faces the tip of the core sleeve pin 25 and the tip of the core pin 26. The ring-shaped narrow distal end surface 25A of the core sleeve pin 25 inserted into the outer plug 2 is in contact with the outer peripheral edge of the upper inner surface 5, and the small circular distal end surface of the core pin 26 also has an upper opening. The edge 3 is in contact with the lower surface of the protrusion 13A.

The inner surface of the core sleeve pin 25 is
The outer surface of the core pin 26 also forms the inner surface of the inner plug 6. The upper end of the inner surface of the core sleeve pin 25 is an enlarged diameter portion, and the inner surface is gradually reduced in diameter by a step 27 and a step 28 connected to the upper end. On the outer surface of the upper part of the core pin 26, an inward corner portion 29 surrounding the outer surface and a groove 30 having a V-shaped cross section surrounding the outer surface are formed below the corner portion 29 at a distance from the corner portion 29. . The inward corner portion 29 faces the vicinity of the enlarged diameter portion on the inner peripheral surface, and the groove 30 faces the smallest diameter portion below the step 28. With the above configuration, as shown in FIG. 5, the outer surface of the inner plug 6 has the above-described enlarged portion, the step 27,
The diameter decreases in the order of the steps 28. Further, the inward corner portion 29 forms a corner portion 19 on the inner surface of the inner plug 6, and the groove 30 forms a projection portion 20 also having a V-shaped cross section.

The fixed mold 22 has a sprue 14 formed therein. The sprue 14 penetrates the projection 13A of the fixed mold 22 and enters the tip of the core pin 26 of the movable mold 23. doing. Therefore, the sprue 14 is provided so as to communicate with the runner gate 24 at the tip of the core pin 26, and the tip of the sprue 14 is located approximately at the middle of the inward corner 29 and the groove 30 on the peripheral surface of the tip of the core pin 26. It is open at the location. If a synthetic resin having flexibility is injected from the sprue 14 through the runner gate 24 into a section surrounded by the core sleeve pin 25, the core pin 26 and the upper inner surface 5 of the outer plug 2, and molded at a predetermined temperature, The wide ring-shaped upper surface 6A of the flange-shaped upper end enlarged diameter portion of the plug 6 is
The inner cap 5 for the carbonated beverage bottle can be molded by fusing with the upper inner surface 5 of the cap, and the outer plug 2 and the inner plug 6 are integrated. FIG. 4 shows a state in which the cap formed as described above is taken out of the fixed mold 22 according to a conventional method. The injection port is pulled out from here, and the molding of the carbonated beverage bottle cap 1 is completed.

FIGS. 6 and 7 show another embodiment of the method for manufacturing a cap for a carbonated beverage bottle according to the present invention. The method shown in this alternative embodiment is basically the same as the method shown in FIGS. 1 and 2, and therefore, the portions denoted by the same reference numerals as those shown in FIGS. 1 and 2 are the same members. . 6 and 7
The characteristic feature of the embodiment shown in FIG. 1 is that a ring-shaped ridge 30 is formed on the upper surface periphery of the upper enlarged diameter portion of the movable mold 9 in the first step.
This is to form a ring-shaped concave groove 31 on the periphery of the upper inner surface 5 of the outer plug 2. In the second step shown in FIG. 7, the distal end 25A of the core sleeve pin 25 is interposed in the concave groove 31 of the outer plug 2, whereby the flexible synthetic resin constituting the inner plug is injected. This prevents resin from escaping from the tip 25A of the core sleeve pin 25, increases the degree of crimping between the upper surface 6A of the inner plug 6 and the upper inner surface 5 of the outer plug 2, and strengthens the fusion between them. is there.

FIG. 8 shows a cross section of the cap for a carbonated beverage bottle of the present invention manufactured by the manufacturing method shown in FIGS. The cap for a carbonated beverage bottle of the present invention shown in FIG. 8 is basically the same as the cap shown in FIG. 5, and the parts denoted by the same reference numerals as those in FIG. 5 indicate the same parts. The feature of the carbonated beverage bottle cap of the present invention shown in FIG. 8 is that the upper edge fused to the inner upper surface of the outer plug 2 is the peripheral edge of the inner upper surface 6A of the outer plug 2. This is a point that a ring-shaped concave groove 31 is formed in contact therewith. That is, at the time of manufacturing, the tip 25A of the core sleeve pin is interposed in the concave groove 31 of the outer plug to prevent the resin from escaping at the time of injecting the inner plug resin, and the crimp strength between the inner plug and the outer plug is increased. Is characterized by the fact that the integration of

[0018]

According to the method for producing a cap for a carbonated beverage bottle of the present invention, a movable mold is inserted into a fixed mold provided with a cavity for molding an outer plug, and a synthetic resin is injected into the cavity. A first step of forming the outer plug, and the outer plug formed in the first step is transferred to another stationary mold having a cavity for forming a cap, and is fitted. Into the stationary mold in the state described above, insert another moving mold into the outer plug, inject synthetic resin, fuse the inner plug to the upper inner surface of the outer plug, mold the outer plug and the inner plug. Since the cap is formed by integrating the stopper, there is an effect that the cap for carbonated beverages in which the outer stopper and the inner stopper are integrated can be easily manufactured. Further, there is an effect that the molding apparatus can be operated by separately setting and managing the molding conditions of the first step of forming the outer plug and the second step of fusing the inner plug to the outer plug to form.

Since the molding conditions suitable for each of the two types of synthetic resins having different molding temperatures and temperature-flow characteristics can be separately set, and the caps for the carbonated beverage bottle can be molded while maintaining these conditions, the number of steps is small. In addition, it has the effect that a product which can be molded with high precision and has no variation in the outer shape and dimensions can be continuously produced at a high yield.

[Brief description of the drawings]

FIG. 1 shows a first method for producing a carbonated beverage bottle cap according to the present invention.
Sectional view showing process

FIG. 2 is a sectional view showing a second step of the method for producing a carbonated beverage bottle cap.

FIG. 3 is a cross-sectional view showing the outer plug as formed in the first step shown in FIG. 1;

FIG. 4 is a cross-sectional view showing the cap as formed in the second step shown in FIG. 2;

FIG. 5 is a sectional view showing a cap for a carbonated beverage bottle.

FIG. 6 is a sectional view showing a first step of another embodiment of the method for producing a carbonated beverage bottle cap of the present invention.

FIG. 7 is a cross-sectional view showing a second step of another embodiment.

FIG. 8 is a cross-sectional view of the cap for a carbonated beverage bottle of the present invention manufactured by the method of FIGS. 6 and 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap for carbonated beverage bottles 2 Outer stopper 5 Upper inner surface 6 Inner stopper 6A Upper surface 7 Fixed side mold 8 Cavity 9 Moving side mold 11 Molding section 12 Large diameter section 13 Small protrusion 14 Sprue 21 Runner gate 22 Fixed side mold 25 core sleeve pin 25A distal end surface 26 core pin 30 ridge 31 groove

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // B65D 41/28 B65D 41/28 C 47/26 47/26 SB29L 31:56 (58) Fields surveyed (Int.Cl. . ^6, DB name) B29C 45/00 - 45/84 B29C 33/42 B29C 39/10 B29C 39/26 B29D 31/00 B65D 41/28 B65D 47/26

Claims (5)

(57) [Claims] 1. A first step in which a movable mold is inserted into a fixed mold provided with a cavity for molding an outer plug, and a synthetic resin is injected into the cavity to form an outer plug. Transfer the outer plug formed in the first step into another fixed-side mold provided with a cavity for molding, insert the outer-side mold into the outer plug, and inject the synthetic resin. And fusing the inner plug to the upper inner surface of the outer plug to form the cap. The cap is formed by integrating the outer plug and the inner plug to form a cap. Manufacturing method. 2. A ring-shaped convex groove is formed on the upper peripheral edge of the upper enlarged-diameter portion of the moving-side mold in the first step to form a ring-shaped concave groove on the upper inner peripheral edge of the outer plug. 2. The cap for a carbonated beverage bottle according to claim 1, wherein the tip of a core sleeve pin constituting another moving side mold in the second step is interposed in the concave groove. Method. 3. The outer plug is formed using a hard synthetic resin, the inner plug is formed using a flexible synthetic resin, and a receiving portion of a bottle mouth is formed between the outer plug and the inner plug. The method for producing a cap for a carbonated beverage bottle according to claim 1 or 2, wherein the inner plug is formed so that the ramune balls can be hermetically stored in the inner plug. 4. An outer cap formed of a hard synthetic resin, having an upper opening at the center and formed in an inverted bowl shape, and a synthetic resin softer than the outer cap, and integrally formed on an upper inner surface of the outer cap. A cap for a carbonated beverage bottle, comprising: a substantially cylindrical inner plug fused to an inner plug, wherein a concave groove in contact with an upper portion of the inner plug is formed on a peripheral edge of an upper inner surface of the outer plug. 5. The inner mold according to claim 4, wherein a movable mold is interposed in the groove to prevent the injected synthetic resin for the inner plug from escaping, and the inner plug is strongly pressed to the outer plug. Cap for soda drink bottle.