JP4618579B2 - Double container and molding method - Google Patents

Description

  The present invention relates to a blow molded casing-shaped synthetic resin double container exhibiting a heat insulating function and a molding method thereof.

  As a synthetic resin container that exhibits a heat insulating effect on the stored contents, the outer container body and the inner container body are combined with a gap formed between them, and between the outer container body and the inner container body. A double container in which a heat insulating action is obtained by the formed gap is known.

The double container having the above-described structure combines the outer container body and the inner container body that have already been formed into a fixed shape, so that the structure can combine the outer container body and the inner container body. Generally, it is in the form of a bowl or cup.
JP 2002-282110 A

  In this case, the external shape and structure of the container are greatly limited, and basically a structure having a large opening, so that it is very unsuitable for storing and holding liquid. there were.

In order to eliminate this dissatisfaction, the outer container body and the inner container body are each molded in a box shape, and the upper half of the outer container body divided into two parts in the top and bottom is assembled to the inner container body at the mouth The outer half of the outer container body is fixed and connected to the upper half of the outer container body so that it covers the inner half of the outer container body. is there.
JP 2002-68324 A

  The double container having the outer shape of the casing can function properly as a liquid storage container in the same manner as a normal casing. This is achieved by assembling the inner container body in a fixed posture and connecting and fixing the other to one side while maintaining the assembled state constant.

  For this reason, there is a problem that at least three parts are required to manufacture one double container, and handling of the parts is complicated and troublesome.

  In addition, since the double container is completed by joining the outer container bodies that are divided into the upper and lower parts, the joint part of the outer container bodies has a high risk of remarkably deteriorating the appearance of the container. There is a problem that it is necessary to conceal the mating portion, and accordingly, the configuration is complicated and the manufacturing cost of the container is increased.

  Further, there is a problem that a complicated sealing structure and a troublesome handling operation are required to form a sealed structure in the gap formed between the outer container body and the inner container body.

  Therefore, the present invention was devised to solve the above-mentioned problems in the prior art, and it is a technical problem to obtain a double container having a void exhibiting a heat insulating action with a simple structure and a molding method. Therefore, an object of the present invention is to make it possible to manufacture a double container that exhibits a heat insulation function with a simple structure and handling at low cost while maintaining the appearance of a normal casing.

Among the present invention for solving the above technical problems, the means of the invention according to claim 1 is:
This is a double container made of a synthetic resin consisting of a body and an outer body, which is blown into a box shape by connecting a mouth tube part through the shoulder to the upper end of the body with the lower end closed at the bottom. There is,
Forming a gap between the content body and the outer body from the shoulder to the bottom, in a state in which the rib strip provided on the surface of either the content body or the outer body is prevented from being crushed ,
Communication between the gap and the content body by means of an open cylindrical piece provided at the lower end of the content body;
It is in.

  In the invention described in claim 1, since the gap formed between the content body and the external body is not in a sealed structure and is in communication with the content body, A part of the stored content liquid enters the gap, and the content liquid and the air in the gap that have entered the gap exert a heat insulating action, and insulate the content liquid in the content body from the outside air.

  The content liquid located in this space is affected by the heat of the outside air to the same extent as a normal synthetic resin casing, but the heat transfer effect by the heat convection due to the heat effect of this outside air is affected by the content liquid in this space. The content liquid in the voids effectively exhibits a heat insulating action.

  Since the gap is not a sealed structure, a sealing structure for sealing is unnecessary, and the assembly structure of the content body and the external body and the assembly handling operation are simple.

  Since the outer container is a structure that remains as an integrally molded product without being divided into two parts in the vertical direction, a line formed by joining does not appear on the outer surface, and a smooth outer surface is formed.

Moreover, the means of invention of Claim 2 among this invention is the following.
Formed in a box shape with a double wall structure with a gap between the shoulder part and the bottom part, with the mouth tube part connected to the upper part of the trunk part with the bottom part closed at the bottom part. , A method of molding a double container made of a synthetic resin composed of a content body and an external body,
An inner preform having an open cylindrical piece at the lower end is inserted and fixed to a bottomed cylindrical outer preform, and the main body is formed by a rib strip provided on either the inner preform or the outer preform. Forming a gap between the inner preform part and the outer preform part of the part to constitute a double preform,
Blow molding this double preform into a double container with the gap sealed,
It is in.

  In the invention according to claim 2, the double preform does not make the gap formed in the main body part hermetically sealed, but simply inserts and assembles the outer preform and the inner preform. As constructed, the assembly and handling process is very simple.

  When the double preform is blow molded into a double container, the gap is not necessarily sealed completely because the blow molding time of the double preform into the double container is extremely short. Even if there is a leak, blow molding of a double preform into a double container can be achieved without any trouble.

  As a means for sealing the gap, it is easy to use clamping with a double preform holding jig or pressing of a stretching pin, but the invention is not limited to this, and other appropriate means can be used. May be used.

  According to a third aspect of the invention, in the configuration of the second aspect of the invention, a neck ring is provided at the lower end of the outer peripheral surface of the mouth tube portion of the outer preform, and the mouth tube of the outer preform is formed on the mouth tube portion of the inner preform. A double preform is formed by providing a locking piece to be locked from above on the part, and this double preform is biaxially stretch blow molded into a double container with the mouth tube part including the neck ring as a support part It is a thing that adds.

  In the invention according to claim 3, it becomes possible to give the double container to be molded the improvement of physical properties accompanying the biaxial stretch blow molding. An improvement in mechanical strength can be obtained.

Since the present invention has the above-described configuration, the following effects can be obtained.
In the invention according to claim 1, since it has a double wall structure having a gap between the shoulder portion and the bottom portion, the content liquid and air that have entered the gap exhibit a heat insulating action, and as a heat insulating container The function of is surely demonstrated.

  Since the gap formed is not required to have a sealed structure, a troublesome sealing structure is not required, and the structure of the container is simplified correspondingly.

  Since the outer surface of the double container is formed of an external body that is an integrally molded product, there is no appearance of the line due to the joining as an appearance appearance, so even if it has a double wall structure with a gap, the appearance A smooth surface with good appearance.

  In the invention described in claim 2, since the assembly and handling process of the double preform is extremely simple, an efficient double container molding operation can be obtained.

  In addition, the air gap sealing required when blow-molding a double preform into a double container is of a level that allows some leakage, and is therefore easy to achieve. It can be easily implemented by using the equipment.

  In the invention described in claim 3, the double container can be provided with improved physical properties associated with biaxial stretch blow molding, whereby a strong and safe double container can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a double container 1 according to the present invention. The double container 1 is provided with a thread on the outer peripheral surface and a neck ring 3 below the thread. The mouth tube portion 2, the shoulder portion 4 connected to the lower end of the mouth tube portion 2 in a tapered tube shape whose diameter is expanded downward, and the trunk portion 5 connected in a hanging manner from the lower end of the shoulder portion 4. And a bottom part 6 that closes the lower end of the body part 5.

  The double container 1 has a double wall structure in which the content body 7 is inserted into the external body 10, and either the content body 7 or the external body body 10 from the shoulder 4 to the bottom 6. A plurality of vertically elongated gaps 12 are formed in a state of being partitioned in the circumferential direction by a plurality of ribs 11 having a plurality of vertical stripes provided in the vertical direction.

  At the center of the bottom of the content body 7, an opening cylinder piece 8 protruding downward with a small height is provided, and the lower end of the content body 7 is opened by the opening cylinder piece 8.

  At the upper end of the content body 7, a hook-like locking piece 9 is provided around the upper end surface of the outer tube 10 of the outer container 10 to be locked. Although the fixed assembly state of the content body 7 is stably maintained, the locking piece 9 does not close the assembly of the content body 7 and the mouth tube portions of the outer container 10.

  For this reason, the gap 12 formed between the content body 7 and the external body 10 communicates the lower end thereof with the inside of the content body 7 through the opening cylinder piece 8, and the upper end thereof is connected with the content body 7 and the external body 7. It leaks through a slight gap formed in the assembled portion of the mouth tube portions of the container 10.

  2 is a longitudinal sectional view showing an example of the structure of a double preform 13 that is biaxially stretch blow-molded in the double container 1 shown in FIG. 1. The double preform 13 has an outer periphery in which a thread is engraved. A bottomed cylindrical main body portion 16 is connected in a hanging manner from the lower end of the mouth tube portion 14 in which a neck ring 15 is provided around the lower end of the surface.

  This double preform 13 is assembled by inserting and assembling a cylindrical inner preform 17 into a cylindrical outer preform 20 having a hemispherical arc-shaped bottom. It has a structure in which a thread and a neck ring 15 are provided on the outer peripheral surface of the part, and the inner preform 17 has a hook shape that abuts and locks with the upper end surface of the outer tube part of the outer preform 20 at the upper end. The opening cylinder piece 18 having a low height is protruded downward in the center of the lower end of the bottom part in the shape of a hemispherical arc shell, and the bottom part is opened by the opening cylinder piece 18. It has become.

  In the body portion 16 of the double preform 13, there are gaps 12 that are partitioned in the circumferential direction by a plurality of longitudinal ribs 21 provided on either the inner preform 17 or the outer preform 20. Although formed, the gap 12 does not have a sealed structure because the assembly of the double preform 13 is completed only by inserting and assembling the inner preform 17 into the outer preform 20.

  FIGS. 3 and 4 are an external perspective view and a bottom view showing an example of the structure of the inner preform 17 with the rib strip 21 formed thereon, and a plurality of (shown implementations) molded to the same protruding height as the opening cylinder piece 18. In the case of the example, the rib strips 21 and the open cylindrical pieces 18 that are in the form of 12) vertical stripes are wide with the rib strips 21 and the open cylindrical pieces 18 remaining on the outer surface portion of the inner preform 17. It is formed by providing a long vertical groove.

  The inner preform 17 shown in FIGS. 3 and 4 is easy to injection-mold because the rib strip 21 extends along the releasing direction.

  FIG. 5 is an external perspective view showing another structural example of the inner preform 17 formed with the rib strip 21, and the rib strip 21 is formed in a spiral ridge shape with the same projecting height as the opening cylinder piece 18. However, in the illustrated embodiment, the structure is a single line, but a double line structure may be used.

  FIG. 6 is a plan view showing an example of the structure of the outer preform 20 with the rib strip 21 formed therein, and a plurality of (in the illustrated embodiment) in the state in which a concave portion into which the opening tubular piece 18 is fitted is formed at the center of the bottom inner surface. In this case, the rib strips 21 in the form of 12) vertical strips are formed by radially projecting the rib strips. In this case, the inner preform 17 portion facing the outer preform 20 portion provided with the rib strips 21 In other words, the thickness of the main body portion of the inner preform 17 is reduced by the protruding height of the rib strip 21 in a state where the open cylindrical piece 18 remains.

  FIG. 7 shows another example of the structure in which the inner and outer preforms 17 and 20 are combined with each other, and an upward stepped portion is formed on the inner peripheral surface of the outer and outer tube 20. A downwardly-stepped locking piece 19 is provided on the outer peripheral surface of the inner preform 17 so as to lock the stepped portion formed on the outer preform 20 from above.

  FIG. 8 shows still another structural example in which the mouth tube portions of the inner preform 17 and the outer preform 20 are assembled. The upper end portion of the outer preform 20 is covered with the upper end portion of the inner preform 17. A hook-shaped hook-like locking piece 19 is provided to be locked from above.

  The double preform 13 shown in FIG. 2 is biaxially stretched and blow molded into the double container 1 shown in FIG. The assembly of the inner preform 17 and the outer preform 20 in the mouth tube portion 14 is performed by holding the double preform 13 by a holding jig (not shown) for holding the biaxial stretch blow molding, and the stretch molding force. By pressing the mouthpiece piece 19 to the outer preform 20, it becomes a substantially dense state, and the opening cylinder piece 18 is sealed by pressing an extension pin (not shown).

  Thus, the double preform 13 is a state in which the gap 12 formed between the inner preform 17 and the outer preform 20 is held in a substantially dense state and is not crushed by the rib strip 11. Thus, since the double container 1 is biaxially stretch blow molded, the gap 12 can be formed in the double container 1.

  In the above description, the formation of the double preform 13 into the double container 1 has been described by biaxial stretch blow molding, but the present invention is not limited to this, and simple blow molding is used. Is also possible.

It is a vertical front view which shows the 1st Example of the double container by this invention. It is a vertical front view which shows the double preform shape | molded by the Example of FIG. It is an external appearance perspective view which shows the structural example of the inner preform which provided the vertical strip-shaped rib strip. FIG. 4 is an enlarged bottom view of the inner preform shown in FIG. 3. It is an external appearance perspective view which shows the other structural example of the inner preform which provided the spiral strip-shaped rib strip. It is an enlarged plan view which shows the structural example of the outer preform which provided the vertical strip-shaped rib strip. It is a vertical front view which shows the other structural example of a double preform. It is a vertical front view which shows the other structural example of a double preform.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Double container 2; Mouth part 3; Neck ring 4; Shoulder part 5; Body part 6; Bottom part 7; Content body 8; Open cylinder piece 9; Locking piece 10; 13; Double preform 14; Mouth tube portion 15; Neck ring 16; Body portion 17; Inner preform 18; Open tube piece 19; Locking piece 20; Outer preform 21;

Claims (3)

  The body (7) blow-molded into a box-like shape by connecting the mouth tube (2) to the upper end of the body (5) whose lower end is closed by the bottom (6) via the shoulder (4). ) And the outer container (10), and the rib (11) provided on the surface of either the contents (7) or the outer container (10). In the state in which the crushing is prevented, a gap (12) is formed between the content body (7) and the external body (10) from the shoulder (4) to the bottom (6), and the content (7 A double container formed by communicating the gap (12) and the content body (7) through an open cylinder piece (8) provided at the lower end of). The upper end of the body (5) whose lower end is closed by the bottom (6) is connected to the mouth tube (2) via the shoulder (4), and extends from the shoulder (4) to the bottom (6). Method for forming a double container (1) made of a synthetic resin comprising a content body (7) and an external body (10), which is formed into a casing shape with a double wall structure having a gap (12) in between An inner preform (17) having an open cylindrical piece (18) at the lower end is inserted and fixed to the bottomed cylindrical outer preform (20), and the inner preform (17) is fixed. A gap (12) between the inner preform (17) portion and the outer preform (20) portion of the main body (16) by the rib strip (21) provided on either the outer preform (20) or the outer preform (20). forming a configured double preform (13), stretching peak of the double preform (13), said opening sleeve piece to the (18) Method of molding double container in a closed state a gap (12), biaxially stretch blow molding said double container (1) by pressing the. A neck ring (15) is provided at the lower end of the outer peripheral surface of the mouth tube portion of the outer preform (20), and the mouth tube portion of the outer preform (20) is engaged with the mouth tube portion of the outer preform (20) from above. A locking piece (19) for stopping is provided to constitute a double preform (13), and the double preform (13) is supported by a mouth tube portion (14) including the neck ring (15). The method for forming a double container according to claim 2, wherein the double container (1) is biaxially stretch blow-molded.

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