JP4352913B2 - Preform with extension part and manufacturing method thereof - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a preform for blow-molding a container, and in particular, a preform with an extending part in which an extending part such as a hanging tool attached to the container is integrally formed in advance at the stage of preform injection molding Regarding the method.

In the case of a container having an extension part such as a container with a conventional lifting tool, the extension part is integrally formed by injection molding from the preform stage, and the preform is molded into a container shape by blow molding (For example, refer to Patent Document 1).
The extending portion is provided with a thin hinge portion and a hanging hole, and it is desirable that the hinge portion and the hanging hole are molded at the stage of injection molding.

  However, since the hinge portion is thin and has a narrow cross section, it becomes a factor that hinders the flow of resin during molding. Also, when the suspension hole is formed, the right and left side edges of the suspension hole have a narrow cross section, which impedes resin flow.

In the above-mentioned Patent Document 1, the portion corresponding to the hinge at the time of blow molding is configured to be locally compressed and thinned, but it is necessary to provide a compression portion corresponding to the hinge portion on the blow molding die, There is a problem that the mold becomes expensive.
As a similar conventional technique, there is JP-B-6-84038.
Utility model registration No. 2565159

  The present invention has been made in order to solve the above-described problems of the prior art, and the object of the present invention is to provide as much resin as possible when injection-molding an extended portion having a narrow cross-sectional portion connected to a preform. It is an object to provide a preform with an extending portion that makes it easy to flow and a method for manufacturing the same.

  In order to achieve the above object, the invention according to claim 1 is a configuration in which an extension portion is integrally formed at the tip of the preform by injection molding, and the tip portion of the extension portion from the base to the preform is formed. In a preform with an extension part having a narrow cross section partly in between, in parallel with the narrow cross section part, a part on the preform side and a part on the opposite side of the preform are connected to the narrow cross section part A connecting portion for enlarging the flow of resin at the time of injection molding is provided.

  The invention according to claim 2 is characterized in that the narrow cross-sectional portion is a thin portion, and the connecting portion is a thick portion provided in a part of the thin portion in the width direction.

  The invention according to claim 3 is configured such that the thick part is divided into a pair of cutting parts on the extension part side and the preform side, and the rotation operation of the extension part centering on the thin part is allowed. It is characterized by.

  The invention according to claim 4 is characterized in that the thick portion is located in the center in the width direction of the thin portion.

The invention according to claim 5 is a structure in which a hole is provided in the extension part, the narrow cross-sectional part is the both side edges of the hole, and the connecting part crosses the hole and is a base part side with the preform of the extension part And the tip end side are connected to each other.
When the invention according to claim 6 has a plurality of narrow cross-sectional portions, a preform-side portion and a portion on the opposite side of the preform with respect to the narrow cross-sectional portion are provided in parallel with at least one narrow cross-sectional portion. A connecting portion is provided for connecting and enlarging the flow of resin during injection molding.

  In the invention according to claim 7, the extension part is integrally formed at the tip of the preform by injection molding, and the extension part has a narrow cross section from the base part to the tip part of the preform with the preform. In the preform manufacturing method, a first cavity portion and a second cavity that are divided into the narrow section molding section in parallel with the narrow section molding section for molding the narrow section section in an injection mold. A connecting passage for connecting the portions is provided, and the resin is caused to flow through the connecting passage together with the narrow section molding portion.

  According to an eighth aspect of the present invention, the narrow cross-section molded portion is a thin gate portion for forming a thin portion, and a thick gate portion having a larger gap than the thin gate portion is provided as a connection passage in a part of the thin gate portion. And providing a thick part in a part of the thin part.

  The invention according to claim 9 is characterized in that, after injection molding, the thick part is divided into a pair of cut parts on the extension part side and the preform side, and the extension part is made bendable around the thin part. To do.

  The invention according to claim 10 is characterized in that the thick gate portion is located in a central portion in the width direction of the thin gate portion.

  The invention according to claim 11 is characterized in that the narrow cross-section molding part molds both side edges of the hole formed in the extension part, and the connection passage is provided in the mold part corresponding to the hole. .

  The invention according to claim 12 is characterized by cutting and removing the connecting portion after injection molding.

  As described above, according to the first aspect of the present invention, the extension part is integrally formed at the tip of the preform by injection molding, and the narrow part is formed in parallel with the narrow cross-sectional part formed in the extension part. Since the connecting portion is provided to connect the portion on the preform side and the portion on the opposite side of the preform with respect to the cross-sectional portion, the flow of the resin can be expanded through the connecting portion at the time of injection molding.

  According to the invention of claim 2, since the thick part connecting the extension part and the preform is provided in a part of the thin part in the width direction, the thin part is thinned to the final thickness at the stage of injection molding. In addition, the resin can be sufficiently flowed through the thick part to the preform side or the extension part side, and there is no need to compress the thin part at the time of blow molding as in the prior art.

  According to the third aspect of the invention, the thick part is divided into a pair of cutting parts on the extension part side and the preform side, and the rotation operation of the extension part around the thin part is allowed. Even if the thickness of the thick part is increased, the movement of the extension part is not hindered.

  According to the invention which concerns on Claim 4, since a thick part is located in the center part of the width direction of a thin part, resin can be poured uniformly into an extension part.

According to the invention which concerns on Claim 5, even when the extension part is perforated structure and the both-sides edge part of a hole has a narrow cross section, the base part side and front-end | tip part with a preform of an extension part crossing a hole are crossed By providing the connecting portion that connects the sides, the resin can sufficiently flow to each portion of the extending portion sandwiching the narrow cross-sectional portion, and molding defects can be prevented.
In addition, since the holes are formed at the injection molding stage except for the connecting part, less wasted resin is removed than when drilling after injection molding, and the amount of resin used can be reduced, reducing costs. Can be planned.
In addition, the injection time and cooling time can be shortened by the reduction in the filling amount for the hole, and the injection molding cycle per hour is increased, leading to improvement in productivity.
Furthermore, since only the connecting portion is removed after injection molding, the size of the cutter can be reduced as compared with the case of punching after injection, the burden on the cutter is reduced, and the drilling efficiency is improved.
According to the invention which concerns on Claim 6, when it has a plurality of narrow cross-section parts, by applying the present invention to at least one narrow cross-section part, it is possible to The amount of resin flowing between the preforms can be secured.

  According to the seventh aspect of the present invention, the first cavity portion and the second cavity section which are divided into the narrow cross-section molding portion, in parallel with the narrow cross-section molding portion for molding the narrow cross-section portion into the injection mold. Since a connecting passage for connecting the cavity portions of the resin is provided and the resin is allowed to flow through the connecting passage together with the narrow cross-section molding portion, the flow of the resin can be expanded through the connecting passage without impeding the flow of the resin. A narrow cross section can be formed.

  According to the invention according to claim 8, the narrow cross-section molded part is a thin gate part for molding the thin part, and a thick gate having a gap larger than the thin gate part as a connection passage in a part of the thin gate part Since the part is provided, the thin part can be formed thinly to the final thickness at the injection molding stage, and the resin can sufficiently flow to the preform side or the extension part side through the thick part. Thus, there is no need to compress the thin portion again during blow molding.

In the invention according to claim 9, after injection molding, the thick part is divided into a pair of cut parts on the extension part side and the preform side, and the extension part is bendable around the thin part.
The blow post-treatment process is simplified as in the prior art.

  In the invention according to claim 10, since the thick gate portion is located at the center in the width direction of the thin gate portion, the resin can be poured uniformly into the extension portion or the molding cavity of the preform.

According to an eleventh aspect of the present invention, the narrow cross-section molding part molds both side edges of the hole formed in the extension part, and the connection passage is provided in the mold part corresponding to the hole. The resin can be sufficiently flowed to each part of the extending part divided by the narrow cross-sectional part, and molding defects can be prevented.
In addition, since the holes are formed at the injection molding stage except for the connecting part, less wasted resin is removed than when drilling after injection molding, and the amount of resin used can be reduced, reducing costs. Can be planned.
In addition, the injection time and cooling time can be shortened by the reduction in the filling amount for the hole, and the injection molding cycle per hour is increased, leading to improvement in productivity.

  Since the invention according to claim 12 cuts and removes the connecting portion, the size of the cutter can be smaller and the burden on the cutter can be reduced compared to the case of drilling after injection. Efficiency is also improved.

  Hereinafter, the present invention will be described based on illustrated embodiments.

FIG. 1 shows a preform with an extending portion according to Embodiment 1 of the present invention.
The preform 1 with the extension part is configured such that a flat extension part 30 is integrally formed at the tip of the preform 10, and between the base part of the extension part 30 and the tip part, in this embodiment, at the base part. The thin portion 20 is partially provided as a narrow cross section. In parallel with the thin portion 20, the thickness as a connecting portion for expanding the flow of the resin at the time of injection molding by connecting a portion on the preform 10 side and a portion on the opposite side of the preform to the thin portion 20. A meat part 40 is provided. The thick portion 40 is provided in a part of the thin portion 20 in the width direction.

The preform 10 includes, for example, a cylindrical body portion 11, an opening portion 12 located at one end of the body portion 11, and a closed hemispherical bottom portion 13 located at the other end of the body portion 11. . A projecting connection seat portion 13 a for connecting the extension portion 30 is formed on the bottom portion 13 so as to protrude. The connecting seat portion 13a is a portion that fills in the difference in shape between the spherical bottom portion 13 and the linear thin portion 20, and the end portion on the bottom portion 13 side is semicircular, and the end portion on the thin portion 20 side is linear. It has become.
The extending portion 30 has a flat plate shape extending on an extension line of the central axis O of the preform 10, has a width corresponding to the diameter of the preform 10, and the tip portion 31 is rounded in a semicircular shape.
The thin-walled portion 20 has a shape in which both side surfaces are constricted in a V-shaped cross section, extends linearly in a direction orthogonal to the central axis O of the preform 10, and the minimum thickness portion forms a line-shaped hinge portion 21. .

The thick portion 40 is located in the center of the thin portion 20 in the width direction, and connects the extension portion 30 and the preform 10 across the thin portion 20. In particular, the end portion on the preform 10 side is the preform bottom portion 13. It is connected to the central vertex. In this embodiment, the thickness of the thick portion 40 is equal to the plate thickness of the extended portion 30.
The preform 10 is formed by blow molding, for example, as a container as shown in FIG. 2, and the extending portion 30 is configured as a hanging tool 230 that is foldably attached to the central recessed portion 220 of the bottom portion 210 of the container body 200. .
In order to be used as the hanging tool 230, the extending portion 30 is provided with a hanging hole 32. The suspension hole 32 may be molded at the same time as injection molding or may be molded after injection molding.

Since the extension part 30 cannot be bent when there is the thick part 40, as shown in FIG. 3, the thick part 40 is cut into a pair of cutting parts 41, 42 on the extension part 30 side and the preform 10 side, The extending portion 20 is allowed to rotate around the hinge portion 21 of the thin portion 20. As shown in FIG. 3, the thick portion 40 may be cut before the container is blow-molded or after the container is blow-molded.
In the folding position, as shown in FIG. 3D, the cutting end surface 41a of one cutting portion 41 can be engaged with the side surface 42b of the other cutting portion 42 to hold the folding posture. At the standing position of the extended portion 30, the cut end surfaces 41a and 42a of the respective cut portions 41 and 42 are engaged with each other so that the suspended posture can be maintained (see FIG. 3B). Further, when the extension part 30 moves between the standing position and the folding position, the corner part 43 of one of the cutting parts 42 bites into the end surface 41a of the cutting part 41 to partially increase the resistance force, thereby (See FIG. 3C).

  By adjusting the amount of biting between the corner portion 43 and the end face 41a, the magnitude of resistance and the feeling of moderation can be adjusted. As the adjustment of the biting amount, adjustment by the thickness of the cutting portion 41, adjustment by the inclination angle of the cutting end surface 41a, adjustment by giving a convex shape to at least one of the corner portion 43 and the cutting end surface 41a, or these Adjustment is possible by combination.

As shown in FIG. 3 (E), the cutting portions 41 and 42 include first slits C1 and C1 that separate the thick portion 40 and the thin portion 20 along both side edges of the thick portion 40, and a first slit. It has a U-shape including a second slit C2 that extends from the upper ends of C1 and C1 in a direction parallel to the rotation axis and cuts the thick portion.
In the case of the present embodiment, the second slit C2 is positioned on the extended portion 20 side from the hinge portion 21 of the thin portion 20, and the first slit C1 has a predetermined dimension across the hinge portion 21 from both ends of the second slit C2. Only extends to the preform 10 side.

In the above embodiment, the thick portion 40 is provided at one central portion of the thin portion 20, but the thick portion 40 may be provided at two locations on the left and right sides, and a plurality of thick portions 40 are provided at other positions. May be.
In addition, the thick portion 40 is used to maintain the folded position and the standing position of the extended portion 30, but the flexible portion can be bent without providing a configuration for maintaining the extended portion 30. If it is only to do, you may make it excise the thick part 40. FIG.

Next, a manufacturing method of the above-described preform with an extending portion will be described with reference to FIG.
That is, the mold 100 has a preform molding cavity 110 and an extension part molding cavity 130. Between the preform molding cavity 110 and the extension molding cavity 130, there is provided a thin gate portion 120 which is a narrow section molding portion for molding the thin portion 20. The thin gate portion 120 has a narrow gap communicating between the preform molding cavity 110 and the extension portion molding cavity 130, and one of the preform molding cavity 110 and the extension portion molding cavity 130 is passed through the thin gate portion 120. Resin is allowed to flow from the cavity into the other cavity to integrally form the preform 10 and the extension 30.

  In this embodiment, the main gate 180 for filling the resin communicates with the extension molding cavity 130, and the resin flows into the preform molding cavity 110 from the extension molding cavity 130 side. ing. In some cases, the main gate portion 180 may be provided on the preform molding cavity 110 side, and the resin may flow from the preform molding cavity 110 to the extension portion molding cavity 130 side.

A connecting passage that is parallel to the thin gate portion 120 and connects between the preform molding cavity 110 that is the first cavity portion divided by the thin gate portion 120 and the extending portion molding cavity 130 that is the second cavity portion. The thick gate portion 140 is provided so that the resin flows through the thick gate portion 140 together with the thin gate portion 120.
The thick gate portion 140 has a larger gap than the thin gate portion 120 and is provided in a part of the thin gate portion 120 in the width direction. In this example, the thick gate portion 140 is located at the center in the width direction of the thin gate portion 120.

At the time of injection molding, the resin flows from the main gate portion 180 into the extended portion molding cavity 130, and further, the resin flows into the preform molding cavity 110 through the thin gate portion 120 and the thick gate portion 140. Since the thin gate portion 120 has a narrow gap and high resistance, the thin gate portion 120 flows into the preform molding cavity 110 through the thick gate portion 140.
Since the thick gate portion 140 is located at the center of the preform molding cavity 110, the thick gate portion 140 flows uniformly into the cylindrical preform molding cavity 110, and a homogeneous preform without a weld line can be molded. Also, the thin gate portion 120 is finally filled with resin, and the thin portion 20 can be molded.

After the injection molding, the hanging hole 32 is extracted from the extending portion 30 and the thick portion 40 is divided into a pair of cut portions 41 and 42 so that the extending portion 30 can be bent around the thin portion 20.
Next, the preform 110 is placed in a blow mold and a container is formed by blow molding.

FIG. 5A shows a preform with an extending portion according to the second embodiment of the present invention.
In the following description, differences from the first embodiment will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
The preform 201 with the extension portion does not have a thin wall portion at the base portion as in the first embodiment, and a suspension hole 232 is integrally formed at the center portion of the extension portion 30. The width between the left and right side edges of the extending portion 30 and the suspension hole 232 is narrow, branching from the base portion 30b on the preform 10 side to the left and right of the suspension hole 232, and the tip portion 30a on the opposite side to the preform 10. It becomes a narrow cross-sectional portion 202 that joins.
In parallel with the left and right narrow cross-sectional portions 202, a connecting portion 204 that connects the base portion 30b on the preform 10 side and the tip portion 30a opposite to the preform 10 to the narrow cross-sectional portion 202 is provided. In the illustrated example, the connecting portion 204 is provided so as to cross the center of the suspension hole 232.

Next, the manufacturing method of the above-mentioned preform with an extension part is demonstrated with reference to FIG.5 (B).
That is, the mold 300 has a preform molding cavity 110 and an extension part molding cavity 330, and a resin is caused to flow from one cavity of the preform molding cavity 110 and the extension part molding cavity 330 to the other cavity. The preform 10 and the extending part 30 are integrally formed.

  The extended portion forming cavity 330 is provided with a circular hole forming land portion 333 for forming the suspension hole 232, and both side edges of the hole forming land portion 333 form a narrow cross section forming portion 334. ing. A connection passage 340 connecting the first cavity portion 331 and the second cavity portion 332 divided by the narrow cross-section molding portion 334 is provided so as to cross the hole forming land portion 333, and the resin is formed into the narrow cross-section molding portion. It flows through the connection passage 340 together with 334.

In the illustrated example, the connecting passage 340 passes through the center portion of the hole forming land portion 333, and the thickness thereof is the same as the thickness of the left and right narrow cross-section forming portions 334. Good.
At the time of injection molding, the resin flows from the main gate part 180 into the first cavity part 331 of the extension part molding cavity 330, flows into the second cavity part 332 on the base side through the narrow section molding part 334 and the connection passage 340, and It flows into the preform molding cavity 110. The narrow cross-section molding portion 334 has a narrow flow path cross section and high resistance, but smoothly flows into the second cavity portion 332 and the preform molding cavity 110 through the connection passage 340.
Since the connecting passage 340 is located at the center of the extension portion molding cavity 330, it can flow uniformly into the cylindrical preform molding cavity 110, and a homogeneous preform without a weld line can be molded.

  After the injection molding, as shown in FIG. 5C, the connecting portion 204 corresponding to the connection passage 340 remaining in the hanging hole 232 of the extending portion 30 is cut out to open the hanging hole 232 in a circular shape. The connecting portion 204 may be left as it is as long as it does not hinder the suspension.

In each of the above embodiments, an example in which one narrow cross section is formed at the stage of injection molding has been described, but the present invention is applied to at least one narrow cross section in the case of having a plurality of narrow cross sections. can do.
6A is an example in which the thin part 20 and the suspension hole 232 are simultaneously injection-molded in the extension part 30, and the thin part 20 is provided with a thick part 40 as a connecting part. In addition, the connecting portion 204 is also provided in the hanging hole 232. In this way, the thin-walled portion 20 and the suspension hole 232 are formed, and a sufficient amount of resin flows between the extending portion 30 and the preform 10 can be secured.
6B is an example in which the thin portion 20 and the suspension hole 232 are simultaneously injection-molded in the extension portion 203, but the connecting portion 204 is provided only in the suspension hole 232, In this example, the thin portion 20 is not provided with a thick portion. In this case, the flow of the resin between the extended portion 30 and the preform 10 is lower than that in FIG. 6A, but a certain degree of fluidity can be secured because the connecting portion 204 is provided in the hanging hole 232, and the thin wall There is an advantage that post-processing for the portion 20 is not required.
Further, although not shown, the thick portion 40 may be provided only for the thin portion 20 without providing the connecting portion for the hanging hole 232.

  In each of the above-described embodiments, the extending portion 30 has been described by taking a hanging tool such as an infusion container as an example. Can also be applied. About accessories, such as a spoon and a stirring bar, you may comprise easily-cutting means, such as a perforated cut, in a thin part, and you may comprise it so that it can cut away.

FIG. 1 shows a preform with an extending portion according to Embodiment 1 of the present invention. FIG. 1 (A) is a partial front view, FIG. 1 (B) is a partial side view, and FIG. ) Is a cross-sectional view taken along the line C-C in FIG. FIG. 2 shows an example of a container formed by the preform with the extension portion of FIG. 1, in which FIG. 2 (A) is a front view of a state in which the lifting tool is raised, and FIG. 2 (B) is the same drawing (A). ) Is a side view of the state in which the suspension is lowered, and FIG. 4D is a bottom view of the state in which the suspension is raised. FIG. 3 shows a configuration example in which the extending part of the preform of FIG. 1 is foldable. FIG. 3 (A) is a partial front view, FIG. 3 (B) is a partial side view, FIG. (D) is an operation explanatory view in a state in which the extension portion is tilted, FIG. (E) is a partially enlarged view of FIG. (A), and FIG. (F) is a partially broken side view of FIG. . 4A and 4B are a front cross-sectional view and a side cross-sectional view showing a schematic configuration of an injection mold of the preform with the extension portion in FIG. FIG. 5 (A) is a front view showing a part of the preform with extension part according to Example 2 of the present invention in phantom lines, and FIG. 5 (B) is the preform with extension part of FIG. Front sectional drawing which shows schematic structure of an injection mold, The figure (C) is a partial front view of the state which cut away the connection part of the hanging hole of the figure (A). 6 (A) and 6 (B) are front views showing a part of the other embodiment of the present invention with phantom lines.

Explanation of symbols

1 Preform with extension,
10 preform,
DESCRIPTION OF SYMBOLS 11 Body part, 12 Opening part, 13 Bottom part, 13a Connection seat part 20 Thin part, 21 Hinge part 30 Extension part, 31 Tip part, 32 Hanging hole 40 Thick part 41, 42 Cutting part, 43 Corner | angular part 41a, 42a Cutting end face, 42b Side face C1, C2 First and second slits 200 Container body, 210 bottom part, 230 lifting tool 100 mold, 110 preform molding cavity, 120 thin gate part 130 extension part molding cavity, 180 main gate 201 Preform with extension,
202 Narrow cross section 232 Hanging hole 30a Tip portion 30b on the opposite side of preform 204 Base portion 204 on preform side Connecting portion 300 Mold 330 Extension portion forming cavity, 333 Hole forming land portion 334 Narrow cross section forming portion 331 Cavity portion, 332 Second cavity portion 340 Connection passage

Claims (12)

A preform with an extending portion having a narrow cross-sectional portion partially between the base portion of the extending portion and the tip portion, wherein the extending portion is integrally formed at the tip end of the preform by injection molding. In
In parallel with the narrow cross-sectional portion, a connecting portion for connecting the preform side portion and the opposite side of the preform to the narrow cross-sectional portion to expand the flow of resin during injection molding is provided. Preform with an extension part characterized by.   The preform with an extension part according to claim 1, wherein the narrow cross-sectional part is a thin part, and the connecting part is a thick part provided in a part in the width direction of the thin part.   The thick part is divided into a pair of cut parts on the extension part side and the preform side, and is configured to allow rotation of the extension part around the thin part. Preform with extension described.   The preform with an extension part according to claim 2 or 3, wherein the thick part is located in a central part in the width direction of the thin part.   A structure in which a hole is provided in the extending part, a narrow cross-sectional part is a side edge part of the hole, and a connecting part is connected to the base part side and the tip part side of the extending part across the hole. The preform with an extension part according to claim 1.   In the case of having a plurality of narrow cross-section portions, a resin at the time of injection molding by connecting a portion on the preform side and a portion on the opposite side of the preform to the narrow cross-section portion in parallel with at least one narrow cross-section portion The preform with an extension part according to claim 1, further comprising a connecting part for enlarging the flow. In the method of manufacturing a preform with an extension part having a narrow cross-sectional part from the base part to the tip part of the extension part with the preform, by integrally molding the extension part at the tip of the preform by injection molding,
A connecting passage for connecting the first cavity portion and the second cavity portion, which are divided into the narrow cross-section molding portion, in parallel with the narrow cross-section molding portion for forming the narrow cross-section portion in the injection mold. And a flow of resin through the connecting passage together with the narrow section molding portion.   The narrow cross-section molding part is a thin gate part for molding a thin part, and a thick gate part with a gap larger than the thin gate part is provided as a connection passage in a part of the thin gate part, and a part of the thin part is provided. The method for producing a preform with an extension part according to claim 7, wherein the thick part is formed.   9. The extension according to claim 8, wherein after the injection molding, the thick part is divided into a pair of cut parts on the extension part side and the preform side, and the extension part can be bent around the thin part. Manufacturing method of preform with protruding part.   The method for producing a preform with an extending portion according to claim 8 or 9, wherein the thick gate portion is located at a central portion in the width direction of the thin gate portion.   8. The preform with an extension part according to claim 7, wherein the narrow cross-section molding part molds both side edges of the hole formed in the extension part, and the connection passage is provided in a mold part corresponding to the hole. Production method.   The method for producing a preform with an extending portion according to claim 11, wherein the connecting portion is cut and removed after injection molding.

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