JP2001247145A - Cap molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cap molding method wherewith a hinged cap having its front end curved can be prevented from deforming when the front end of its spout is closed after molding, and leakage can be prevented from occurring to the hinged cap. SOLUTION: The hinged cap 14 is formed so that an opening 20a at the front end 22a of a spout 22 approximately in a tubular shape projecting upward from a top face 18 of the cap main body 16 and having at its inside a passage connecting to the inside and outside of a container 10 is formed to open toward the side of the container, and the cap main body 16 and a cap part 24 are formed, being connected with a hinge 26, as an integral shape by injection molding. On molding the hinged cap 14, the cap part 24 is put for closing on the cap main body 16 when the surface temperature of the hinged cap 14 comes down to a level below 30 deg.C after injection molding. As the cap part 24 is put for closing after completion of mold shrinkage, deformation does not occur and a protuberant part 24a of the cap part is stuck close to the opening 20a and leakage of liquid can be prevented certainly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cap molding method suitable for integrally molding a cap in which a cap body and a lid are connected by a hinge.

[0002]

2. Description of the Related Art In general, a cap provided at a container mouth has a cap body provided with a cylindrical spout which communicates inside and outside of the container with an internal pouring hole. There is a hinge cap in which a lid is connected with a hinge and the opening of the spout is opened / closed by removing / attaching the lid.

In this type of hinge cap, for example, as shown in FIG.
A cylindrical spout port c that communicates the inside and outside of the container is formed on the top. This spout portion c extends vertically upward from the top surface,
The lid d is connected to the cap body a by a hinge e. Then, when the plug portion f formed on the lower surface side of the lid portion d is fitted to the cap body a, the lid portion d is fitted into the spout portion c to be hermetically sealed.

In the hinge cap, for example, as shown in FIG. 7, a base end portion c1 of the spout portion c extends almost vertically from the top surface to a middle portion, and the middle portion is bent and a front end portion c2 is formed.
Are almost parallel to the top surface and extend so that the whole has an almost inverted “L” shape. For this reason, the spout is open toward the container side which is substantially perpendicular to the container axis g. Therefore, by inclining the container, it is easy to direct the opening of the spout to the target location,
The liquid in the container can be easily poured into a target location. When the lid d is mounted on the cap body and closed, the projection f inside the lid is fitted into the opening at the tip of the spout c to be sealed.

[0005]

When the above-mentioned hinge cap is formed, the cap body and the lid are integrally injection-molded in a state of being connected by a hinge. However, conventionally, the lid is formed by molding. Immediately after, it was fitted to the cap body and closed.

However, in the case of a hinged cap such as the hinge cap shown in FIG. 7 in which the spout has a spout hole, the spout port is bent immediately after molding. Since the internal projection is fitted, the tip of the spout is pressed and deformed, and there is a concern that liquid leakage may occur.

In view of the above circumstances, the present invention does not cause deformation when the tip of the spout is pointed after molding, even if the tip of the hinge cap is bent, thereby preventing the occurrence of liquid leakage. It is intended to provide a cap forming method which can be performed.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a method of forming a cap, and more particularly to a method of forming a cap. In a hinge cap formed such that the opening of the communication hole opens toward the side of the container, injection molding is performed integrally with the hinge body in a state where the cap body and the lid are connected by a hinge. Later, after the surface temperature of the hinge cap has dropped to 30 ° C. or less, the lid is covered on the cap body.

Therefore, according to the present invention, the lid is fitted to the cap body in a state where it is cooled to 30 ° C. or less and hardened and hardly deformed. Therefore, it is possible to reliably prevent liquid leakage.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 5 show an example of a hinge cap according to an embodiment of the present invention. FIG. 1 is an overall explanatory view of a container with a cap attached thereto, FIG. 2 is a sectional view of the hinge cap, FIGS. 4 is an enlarged explanatory view around the hinge of the hinge cap, and FIG. 5 is an explanatory view showing a state where the spout is closed.

As shown in FIG. 1, a hinge cap 14 is screwed and attached to the mouth 12 of the container 10. As shown in FIG. 2, the hinge cap 14 projects upward on the top surface 18 of the cap body 16 and has the container 1 inside.
0 is a roughly cylindrical spout 2 in which communication holes 20 inside and outside are formed.
The second end 22a is formed such that the opening 20a of the communication hole 20 opens toward the container side (upward at a right angle to the cap body shaft 16a). Then, the cap body 16 and the lid 24 are integrally injection-molded in a state where they are connected by a hinge 26. Lid 24
In the inside, the lid 24 is provided with the cap body 16.
A spherical projection 24a is formed to protrude and fit into the communication hole opening 20a to close the opening 20a when fitted to the communication hole opening 20a.
Further, a wall portion 24b is formed so as to support the spout portion 22 from the side opposite to the protruding portion 24a and position the spout portion 22 pressed by the protruding portion 24a so as not to escape (FIG. 5).
reference).

As shown in FIG. 3, the cap main body 16 is provided with a liquid receiver 16b near the periphery of the top surface for preventing dripping of the adhering liquid remaining in the spout 22. A protrusion provided around the upper end of the liquid receiver 16b and a protrusion 24 formed over the entire inner periphery of the lower edge of the lid 24
c is fitted so that the lid portion 24 is removably opened and closed on the cap body 16. As shown in FIG. 3, the hinge cap 14 has a wall-shaped projection 28 formed on the side surface on which the hinge 26 is formed, with a tip 28 a having a circular cross section.
A groove 30 into which the wall-like projection 28 fits is formed on the slope of the lid portion 24 on the hinge 26 side. This allows
When the lid 24 is opened to pour out the liquid in the container 10, as shown in FIG. 4, the wall-shaped projection 28 is fitted into the groove 30 so that the lid 22 does not shake and does not interfere. it can.

Here, when the hinge cap 14 is molded, injection molding is performed with a molding die. After the injection molding, and after the surface temperature of the hinge cap 14 has dropped to 30 ° C. or less, the lid 24 is moved to the cap body. 16 and close. By closing the lid 24 not just immediately after molding but after molding shrinkage is completed, the projection 24 is not deformed.
a is tightly adhered to the communication hole opening 20a, and liquid leakage can be reliably prevented. The surface temperature drops to 30 ° C. or less, for example, after 24 hours, and it is appropriate to close the lid after that.

The material of the hinge cap is P
P (polypropyne) alone or a resin in which LDPE (low density polyethylene) is mixed by 10 to 50% may be used.

Next, regarding the above-mentioned hinge cap, when the surface temperature exceeds 30 ° C. after injection molding (Comparative Example) and when the surface temperature is 30 ° C. or less (Examples 1 and 2 of the present invention).
In 2) and 3), the lids were closed, and a liquid leakage confirmation test was performed. The results are shown in the table below. In this case, the material was PP.

[0017]

[Table 1] From the above test, the lid closed after the molding caused a liquid leak immediately after the molding as in the comparative example. However, as in Example 1 of the present invention, when the temperature was below 27 ° C. to 28 ° C. 25 degrees C
It was confirmed that no liquid leakage occurred when the temperature was lowered to 30 ° C. or less as in the case of (1).

The method of forming a cap according to the present invention is not limited to the illustrated example described above, and it goes without saying that various changes can be made without departing from the spirit of the present invention.

[0019]

As described above, according to the method of forming a cap according to the present invention, even if the tip of the hinge cap is bent, deformation occurs when the tip of the spout is pointed out after molding. An excellent effect of preventing the occurrence of liquid leakage can be achieved without causing such a problem.

[Brief description of the drawings]

FIG. 1 shows an example of a hinge cap according to an embodiment of the present invention, and is an overall explanatory view of a container to which the cap is attached.

FIG. 2 is a sectional view of a hinge cap.

FIG. 3 is an enlarged explanatory view around a hinge of a hinge cap.

FIG. 4 is an explanatory view showing a state in which a lid portion of a hinge cap and a cap body are combined.

FIG. 5 is an explanatory view of a state where a spout is closed.

FIG. 6 is an explanatory diagram of a general example of a hinge cap.

FIG. 7 is an explanatory view of another general example of a hinge cap.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Container 14 Hinge cap 16 Cap main body 20 Communication hole 22 Outlet part 24 Cover part 24a Projection part 24b Wall part 26 Hinge 28 Wall-like projection 30 Groove

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference)

Claims (1)

[Claims] At the tip of a spout portion that projects upward on the top surface of a cap body and has communication holes inside and outside the container formed therein, the opening of the communication hole opens toward the container side. In the formed hinge cap, when the hinge cap is formed by injection molding integrally with the cap body and the lid connected by a hinge, the surface temperature of the hinge cap after injection molding is 30.
A cap forming method, wherein the lid is covered on the cap body after the temperature has dropped to a degree C or less.