JP2023149813A - Molded body with fitting part - Google Patents

Abstract

To create a molded body with a fitting part that reduces variation in a projection part formed protrusively at an outer peripheral surface of an outer cylindrical body and enables precise control of a fitting strength between the projection part and a recessed part that fit into it.SOLUTION: A molded body having a fitting part in which a recessed part 9a formed on an inner peripheral surface of a side wall 9B fits into a projection part 6a formed on an outer peripheral surface of an outer cylinder part 6 is configured such that a recessed part 6b that is depressed toward an outside in a radial direction is formed on the inner peripheral surface of the outer cylinder part 6 that faces the projection part 6a on an inside in the radial direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a molded article having a fitting portion.

For example, on the outer peripheral surface of the mounting cap 10 screwed onto the outer periphery of the mouth and neck part 9 of the container body 2, a plurality of (for example, three) protrusions projecting outward in the radial direction are provided at regular intervals in the circumferential direction. There is a known prior art in which the overcap can be attached to the head of the container body 2 by fitting an annular recess provided on the inner surface of the overcap into a plurality of convex parts (see Patent Document 1). (see Figure 1).

Publication No. 6-69162

However, molded objects such as the mounting cap 10 having the above-mentioned convex portions are usually formed by injection molding, but if sink marks occur due to shrinkage after molding, for example, variations in the molding accuracy of the convex portions occur. There has been a problem in that it is difficult to accurately manage the fitting strength between the convex portion and the annular recess on the overcap side.

In order to solve the above-mentioned problems in the prior art, the present invention reduces variations in the protrusions formed protrudingly on the outer circumferential surface of the outer cylinder, and increases the strength of the fit between the protrusions and the recesses that fit into the protrusions. The object of the present invention is to create a molded body having a fitting part that can be controlled with high precision.

Among the means for solving the above problems, the main means of the present invention are:
A molded body having a fitting portion in which a concave portion formed on an inner circumferential surface of a side wall fits into a convex portion formed on an outer circumferential surface of an outer cylinder portion,
It is characterized in that a recess that is depressed toward the outside in the radial direction is formed on the inner circumferential surface of the outer cylindrical portion that faces the convex portion on the inside in the radial direction.
According to the main means of the present invention, variations in the protrusions can be reduced by forming protrusions on the radially outer surface of the outer cylindrical portion and forming recesses on the back surface (radially inner surface) thereof.

Further, another means of the present invention is the above-mentioned main means of the present invention in addition to the above-mentioned main means of the present invention.
With the above means, the thickness between the convex portion and the concave portion can be made uniform, and variations among the plurality of convex portions can be reduced.

Further, another means of the present invention is a means in which at least three convex portions are formed on the outer circumferential surface of the outer cylindrical portion at equal intervals in the circumferential direction. It was added.
With the above means, it is possible to equalize the fitting strength in the circumferential direction. In particular, since the protrusions formed intermittently in the circumferential direction can be managed with high precision, the fitting strength in the entire circumferential direction (in this example, the fitting strength between the attached cap and the overcap) can be set to a more appropriate value. can do.

Further, another means of the present invention is that an inner cylindrical part that can be engaged with the container body is integrally formed in any of the above means on the radially inner side of the outer cylindrical part in which the convex part is formed; A gap is provided between the outer cylindrical part and the inner cylindrical part.
With the above means, mold release during injection molding can be facilitated.

In the present invention, by forming a protrusion on the radially outer surface and forming a recess on the back surface (radially inner surface), variations in the protrusion are reduced and the fitting between the protrusion and the recess is improved. Strength can be controlled with high precision.

FIG. 2 is a side view showing a discharge container as an example of a molded article having a fitting portion of the present invention. The mounting cap that constitutes the discharge container is shown, (a) is a half sectional view of the mounting cap, and (b) is a bottom view of the mounting cap. FIG. 3 is a partial cross-sectional view showing a mounting cap and a mold for injection molding the mounting cap.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, a dispensing container 1 as a molded body having a fitting portion according to the present invention includes a container body 2 in which a liquid (not shown) to be discharged is mainly stored, and an upper end of the container body 2. It has a mounting cap 7 to be attached, a push-down head 8 provided on the top of the mounting cap 7, and an overcap 9 that is fitted over the head of the container body 2 and stores the mounting cap 7 and the push-down head 8 inside. It is configured as follows.
In the following explanation, the vertical direction means the direction along the container axis O, the circumferential direction means the direction going around the container axis O, and the radial direction means the direction perpendicular to the container axis O. do.

The container body 2 is a container having a bottomed cylindrical container body with a spout (not shown) erected at the top of the container through a diameter-reduced shoulder 3. is formed with a male screw (not shown) that screws into the mounting cap 7.

As shown in FIG. 2, the mounting cap 7 is a molded product that is formed into a concentric shaft shape and has an inner cylinder part 5 provided on the radially inner side and an outer cylinder part 6 provided on the radially outer side. be. The outer cylinder part 6 has a flange 7A projecting outward in the radial direction at the lower end, and the upper end is formed in a shape that curves inward in the radial direction toward the top, and is formed into a right cylindrical shape. It is integrally connected to the inner cylinder part 5. A gap 7a is formed between the inner cylinder part 5 and the outer cylinder part 6. A flange-shaped intermediate wall 5A is formed at an intermediate height position on the inner circumferential surface side of the inner cylinder portion 5. The flange-shaped intermediate wall 5A is provided with a through hole 5a vertically penetrating in the center. Further, a female thread 5b is formed on the inner circumferential surface of the inner cylindrical portion 5 at a position below the intermediate wall 5A, and is threadedly engaged with the male thread on the container body 2 side. Note that the surface of the mounting cap 7 can also be decorated, for example, by vapor deposition or painting.

On the outer circumferential surface of the outer cylinder part 6, a plurality of protrusions 6a (in this embodiment, three at intervals of 120 degrees) that protrude outward in the radial direction are formed at equal intervals in the circumferential direction. . Further, on the inner circumferential surface of the outer cylindrical portion 6 corresponding to these convex portions 6a (the back surface of the outer cylindrical portion 6 on which the convex portions 6a are formed), concave portions 6b that are depressed toward the outside in the radial direction are formed, respectively. .

The push-down head 8 has a discharge hole 8a on the front side of the upper side, a stem (not shown) inserted into the through hole 5a at the lower end, and a cylinder (not shown) suspended from the lower end, Together with the mounting cap 7, it constitutes a pump mechanism. When the push-down head 8 is operated to move up and down, the pump mechanism is activated, and the liquid inside the container body 2 can be sucked up and discharged from the discharge hole 8a.

The overcap 9 is a capped cylindrical member (molded product) in which a long cylindrical side wall 9B is suspended from the outer edge of the top wall 9A, and the lower end of the side wall 9B is open. An annular recess 9a is provided on the inner circumferential surface of the lower end of the side wall 9B, and when the overcap 9 is fitted onto the head of the upper end of the container body 2, the annular recess 9a becomes a convex part on the mounting cap 7 side. 6a. The convex portion 6a formed in the outer cylindrical portion 6 of the mounting cap 7 and the concave portion 9a formed in the overcap 9 form a fitting portion.

In particular, in the present invention, the protrusion amount e of the convex portion 6a formed on the outer peripheral surface of the outer cylinder portion 6 on the mounting cap 7 side and the recess amount d of the recess portion 6b formed on the inner peripheral surface of the outer cylinder portion 6 are formed equally. With such a configuration, it is possible to reduce variations in the amount of protrusion e between the plurality of convex portions 6a formed on the outer peripheral surface of the outer cylinder portion 6, and as a result, the convex portion 6a and the annular concave portion 9a This makes it possible to precisely control the strength of the fit between the two.

The reason is as follows. That is, as shown in FIG. 3, the mounting cap 7 is formed by injecting molten resin into the mold 10 from a gate (not shown) provided on the upper side. A cavity mold 11 having a mold recess 11a formed on the outer peripheral surface for forming the recess 6b, and a core mold 12 having a mold protrusion 12a formed on the inner peripheral surface for forming the recess 6b are used. It is formed. At this time, the mold recess 11a and the mold protrusion 12a are arranged to face each other in the radial direction, and the recess amount of the mold recess 11a and the protrusion amount of the mold protrusion 12a are made equal. Then, the molten resin flows from the top to the bottom between the core mold 12 and the cavity mold 11, but by forming the mold convex part 12a, the flow of the resin is controlled by the mold concave part 11a. As a result, pressure is applied to the outside in the radial direction, making it possible to reliably form the convex portion 6a.
Furthermore, by making the amount of protrusion of the mold protrusion 12a and the amount of depression of the mold recess 11a equal, it is possible to suppress the formation of thick portions and more reliably suppress the occurrence of sink marks.

Furthermore, when releasing the mold, it is necessary to move the core mold 12 downward relative to the cavity mold 11 to separate it, but a gap 7a is provided between the inner cylinder part 5 and the outer cylinder part 6. This facilitates the removal of the mold protrusion 12a from the recess 6b, thereby improving moldability.

Although the structure of the present invention and its effects have been described above with reference to Examples, the embodiments of the present invention are not limited to the above-mentioned Examples.
For example, in the above embodiment, three protrusions 6a are formed on the outer peripheral surface of the outer cylindrical part 6. However, the number of protrusions 6a is not particularly limited. It may be one annular convex portion that extends continuously in the direction.

Further, in the above embodiment, the circumferential spacing between the plurality of convex portions 6a is 120 degrees, but other spacings may be used.

Further, in the above embodiment, the case where the container main body 2 and the mounting cap 7 are engaged with each other by screws is shown and explained, but other configurations in which undercut-shaped engagement portions are engaged with each other may be used.

Further, in the above embodiment, the discharge container 1 was shown and explained as an example of a molded body having a fitting portion, but other molded bodies may be used.

The present invention can be applied to a wider range of applications in the field of molded bodies having a fitting portion where a convex portion and a concave portion fit together.

1 : Discharge container 2 : Container body 3 : Shoulder part 5 : Inner cylinder part 5A : Intermediate wall 5a : Through hole 5b : Female thread 6 : Outer cylinder part 6a : Convex part (fitting part)
6b: Recess 7: Mounting cap (molded body)
7A: Flange 7a: Gap 8: Push-down head 8a: Discharge hole 9: Overcap (molded body)
9A: Top wall 9B: Side wall 9a: Annular recess (fitting part)
10: Mold 11: Cavity mold 11a: Mold recess 12: Core mold 12a: Mold protrusion O: Container axis d: Recess amount e: Projection amount

Claims (4)

The molded body has a fitting portion in which a concave portion (9a) formed on the inner circumferential surface of the side wall (9B) fits into a convex portion (6a) formed on the outer circumferential surface of the outer cylinder portion (6). hand,
A fitting characterized in that a recess (6b) that is depressed toward the outside in the radial direction is formed on the inner circumferential surface of the outer cylinder part (6) that faces the convex part (6a) on the inside in the radial direction. A molded body with a joint. The molded article having a fitting portion according to claim 1, wherein the protrusion amount (e) of the convex portion (6a) and the concave amount (d) of the recess portion (6b) are formed to be equal. The molded article having a fitting portion according to claim 1 or 2, wherein at least three or more convex portions (6a) are formed on the outer circumferential surface of the outer cylinder portion (6) at equal intervals in the circumferential direction. . An inner cylinder part (5) that can be engaged with the container body (2) is integrally formed on the radially inner side of the outer cylinder part (6) in which the convex part (6a) is formed. The molded article having a fitting part according to any one of claims 1 to 3, wherein a gap (7a) is provided between the inner cylinder part (5) and the inner cylinder part (5).

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