JP2003175540A - Apparatus and method for manufacturing hollow molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a hollow molding in less holding molds by using a relatively simple constitution. <P>SOLUTION: The apparatus for manufacturing so-called 2-station type hollow molding comprises the holding mold 5 for holding a final hollow molding to eliminate the holding of the molding (Fig. (e)) during a returning period of the mold 5 from a blow molding machine 2 to an injection molding machine 1, and recovering the molding. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for producing hollow molded articles such as PET bottles.

[0002]

2. Description of the Related Art As a technique for producing a hollow molded product such as a PET bottle, a technique is proposed in which a preform made of a synthetic resin or the like is prepared by injection molding and then a blow molded product is prepared from the preform by stretch blow molding. Has been done.
Further, as a device for realizing such a manufacturing technique, for example, a device described in Japanese Patent Application Laid-Open No. 3-142220 or Japanese Patent Application Laid-Open No. 4-331126 is known.

These devices are called a three-station type, and a holding mold is provided on a rotary disk. Preforms and hollow molded products are held by this holding mold, and injection molding is performed by rotating the rotary disk. , Stretch-blow molding, and hollow molded article collection. This holding die constitutes a part of a die for making a preform in an injection molding machine, and after the preform is made, it is separated from the rest of the die, and thereafter, the preform during transportation and It functions as a holder for the hollow molded product.

Further, in the above apparatus, about 120
By providing three sets of holding molds at intervals of 120 degrees and arranging the three processing stations under the turntable at intervals of about 120 degrees respectively, holding is performed with intermittent rotation of the turntable every 120 degrees. The mold is configured to move through each processing station in a circular fashion.

Since the holding die described above is used as a part of a die for making a preform, a relatively high working accuracy is required in its manufacture. Therefore, the holding mold is generally expensive, which is one of the causes of an increase in the manufacturing cost of the device.

Therefore, for example, Japanese Patent Laid-Open No. 5-77311
In the gazette, the holding mold is attached to the rotating plate at intervals of about 180 degrees.
An apparatus called a two-station type in which a number of holding dies is reduced is also proposed.

[0007]

However, JP-A-5-7
According to the two-station type device described in Japanese Patent No. 7311, the drawing blow station is provided with a take-out device for collecting the blow-molded hollow molded article.
The device tends to be complicated.

[0008] Therefore, an object of the present invention is to provide a manufacturing apparatus and a manufacturing method capable of manufacturing a hollow molded product with a relatively simple structure and a smaller number of holding dies.

[0009]

According to the present invention, an injection molding machine for producing a preform of a hollow molded article by injection molding, and an injection molding machine which is arranged so as to face the injection molding machine and is blow-molded from the preform. A blow molding machine for producing a hollow molded product, a part of a mold for injection molding by the injection molding machine, two holding means capable of holding the preform and the hollow molded product, and a predetermined rotation. The two holding means are rotatably provided around the center and support them in a state of being symmetrically arranged with respect to the center of rotation, and the rotation of the holding means causes the holding means to move between the injection molding machine and the blow molding machine. And a turntable for carrying between
There is provided an apparatus for manufacturing a hollow molded product, wherein the holding means releases the holding of the hollow molded product created by the blow molding machine while being conveyed from the blow molding machine to the injection molding machine.

Further, according to the present invention, an injection molding machine, a blow molding machine arranged to face the injection molding machine, and a part of a mold for injection molding by the injection molding machine are formed, Hollow molding using a device, which is a holding means capable of holding a molded product created by the injection molding machine and the blow molding machine, and two holding means symmetrically arranged about a predetermined rotation center. A method of manufacturing a product, the step of creating a preform of a hollow molded product by the injection molding machine and one of the holding means, while holding the preform by the one of the holding means, around the rotation center A step of conveying the preform to the blow molding machine by rotating the holding means; and a step of removing the preform from the preform held by the one holding means by the blow molding machine. While making a molded article, a step of creating a preform of a hollow molded article by the injection molding machine and the other holding means, and holding the hollow molded article by the one holding means, and by the other holding means While holding the preform, by rotating the holding means around the rotation center, the preform is conveyed to the blow molding machine and, while the holding means is rotating, the one holding means is used. Provided is a method for manufacturing a hollow molded product, which includes the step of releasing the holding of the hollow molded product.

In the manufacturing method of the present invention, "to release the holding of the hollow molded article by the one holding means during the rotation of the holding means" means that the rotation is performed during the rotation of the holding means. Is temporarily stopped and the holding of the hollow molded article by the one holding means is released.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing the structure of a hollow molded article manufacturing apparatus A according to an embodiment of the present invention. In the present embodiment, a bottle is described as an example of the hollow molded product to be manufactured, but the present invention is not limited to this, and is applicable to the manufacture of various hollow molded products.

In FIG. 1, on a bed 100, an injection molding machine 1, a blow molding machine 2 arranged so as to face the injection molding machine 1, and a collection box 6 for collecting the created bottle.
And are installed. Further, above these, two bases 102 and 103 are supported by the bed 100 via a support rod 104 provided upright on the bed 100. The boards 102 and 103 can be moved up and down along the support rod 104 by a lifting device (not shown).

On the lower surface of the base plate 102, a disk-shaped rotary disk 3 is provided.
Is rotatably provided. The turntable 3 has a base 102.
It is attached so as to be suspended from the output shaft of the rotary actuator 4 provided at the substantially center of the above, and is rotatable about the rotation center P by the rotation of the rotary actuator 4.

On the lower surface of the turntable 3, there are two sets of holding molds 5a.
And 5b (collectively referred to as a holding mold 5) are attached and supported by the turntable 3 so that they are conveyed by the rotation of the turntable 3. The holding mold 5
It constitutes a part of a mold for injection molding by the injection molding machine 1, and holds the molded products produced by the injection molding machine 1 and the blow molding machine 2, respectively. For this reason, the holding mold 5 constitutes a split mold that can be opened and closed, and a mold of the neck portion of the bottle (the portion where the bottle lid is screwed) is engraved inside thereof. FIG. 1 shows a mode in which the holding mold 5a holds the bottle preform X and the holding mold 5b holds the bottle Y made from the preform X.
Each of the holding molds 5a and 5b can be configured to hold one or a plurality of preforms X and bottles Y, but in this embodiment, two cases will be assumed and described.

The holding dies 5a and 5b are supported on the turntable 3 so as to be symmetrical with respect to the rotation center P. That is, the rotation centers P are provided at intervals of 180 degrees. As described above, the injection molding machine 1 and the blow molding machine 2 are arranged to face each other, but they are arranged so that the molding positions of the molded products are symmetrical with respect to the rotation center P. Therefore, when the holding mold 5a is arranged on the injection molding machine 1, the holding mold 5b is not attached to the blow molding machine 1.
It is placed above, and when the turntable 3 is rotated 180 degrees,
The reverse of this is the positional relationship.

Next, the structure of the injection molding machine 1 and the procedure of the injection molding will be described with reference to FIGS. 1 and 2.
2A to 2C are diagrams showing the processing procedure of the injection molding machine 1.

The injection molding machine 1 is a device for producing a hollow preform X by injection molding, and includes a cavity mold 11 which constitutes a mold for producing the preform and a preform which is inserted into the cavity mold 11. An injection core mold 12 that constitutes a mold on the inner surface of X and a hot runner 13 that introduces a molten synthetic resin into the cavity mold 11 are provided. The synthetic resin is supplied from the injection device 101 to the hot runner 13. The injection core mold 12 can be inserted through holes provided in the base 102 and the turntable 3,
A hydraulic cylinder 105 mounted on the base 103 can move up and down.

FIG. 2A shows a state in which the base 102 is lowered to mount the holding mold 5 on the cavity mold 11, and the injection core mold 12 is lowered to be inserted into the cavity mold 11. . A small space is formed between the outer surface of the injection core mold 12 and the inner surfaces of the holding mold 5 and the cavity mold 11, and this space serves as the mold of the preform X. The holding mold 5 finally constitutes the mold of the part which becomes the neck part of the bottle Y, and the cavity mold 11 forms the mold of the part which becomes the body part of the bottle Y.

In the state shown in FIG. 2A, the hot runner 13
When the molten synthetic resin is poured into the above space and cooled, the synthetic resin is hardened to form the preform X.
Then, the injection core mold 12 is raised to move the cavity mold 11
FIG. 2B shows a state in which this is removed. When the substrate 102 is further raised from this state, the preform X is held by the holding mold 5 and released from the cavity mold 11,
The mode shown in FIG. 2C is reached. Since the holding mold 5 is the mold of the neck portion and has the unevenness, the preform X is held therein. However, since the cavity mold 11 is the mold of the body portion and has no unevenness, the preform X is easily formed. I will come out. With the above, injection molding is completed.

Next, the structure of the blow molding machine 2 and the procedure of the blow molding will be described with reference to FIGS. 1, 3A and 3B. 3A and 3B are diagrams showing the processing procedure of the blow molding machine 2.

The blow molding machine 2 blow-molds the preform X produced by the injection molding machine 1 into a bottle Y.
In this embodiment, a molding method called stretch blow molding is adopted. This is a molding method in which not only air is blown into the preform X to expand it, but also the preform X is stretched in its longitudinal direction by a stretching rod.

The blow molding machine 2 comprises a split mold 21 which constitutes a mold for making a bottle, a stretching rod 22 which stretches the preform X, and a mold clamping cylinder 23 which opens and closes the split mold 21.
And a blowing core 24 for blowing air into the preform X
And The stretching rod 22 and the blow core 24 can be inserted through holes provided in the base 102 and the turntable 3. Air cylinders 107 mounted on 102 can be raised and lowered independently of each other.

FIG. 3A (a) shows a state in which the split mold 21 is closed by the mold clamping cylinder 23, the base 102 is lowered, and the holding mold 5 holding the preform X is mounted on the split mold 21 and injected. Split mold 2 for preform X that has residual heat during molding
The aspect arrange | positioned in 1 is shown. Further, FIG. 3A (a)
Then, the blow-in core 24 is lowered to be inserted into the neck portion of the preform X, and the stretch rod 22 is in a state of entering the inside of the preform X.

In the state of FIG. 3A (a), when air is blown into the preform X from the blow-in core 24 and the stretching rod 22 is lowered, the preform X expands in the left-right direction and stretches in the vertical direction. , The bottle Y along the mold on the inner surface of the split mold 21. The mode is shown in FIG. 3A.
It is (b). The shape of the neck portion hardly changed.

After cooling the bottle Y, the blow core 24
Then, the stretching rod 22 is lifted and pulled out from the inside of the bottle Y, the split mold 21 is opened by the mold clamping cylinder 23, and the bottle Y is released. This mode is shown in FIG. 3B (c). Finally, when the base 102 is raised, the bottle Y is held by the holding mold 5 and rises. This mode is shown in FIG. 3B (d). With the above, blow molding is completed.

Next, the process flow of the entire manufacturing apparatus A will be described. The manufacturing apparatus A is controlled as follows by a control device (not shown). 4A to 4F are schematic views showing each processing step in the manufacturing apparatus A, and are plan views of the main part of the manufacturing apparatus A.

First, as shown in FIG. 4 (a), the holding mold 5a is on the injection molding machine 1, and the holding metal fitting 5b is on the blow molding machine 2.
The base 102 in a state in which they are arranged on top of each other.
And the holding mold 5a is used as a part of the mold by the above-described procedure to prepare the preform X by the injection molding machine 1.

Next, the base 102 is raised to hold the holding die 5a.
While holding the preform X on the
By rotating it once, the holding molds 5a and 5b are conveyed as shown in FIG. 4 (b). In this state, the holding mold 5b is located on the recovery box 6 and the holding mold 5b is open, the reason for which will be described later.

Next, by further rotating the turntable 3 by 90 degrees, the holding mold 5a is placed on the blow molding machine 2 and the holding mold 5b is placed on the injection molding machine 1, as shown in FIG. 4 (c). Then, they are respectively conveyed and the base 102 is lowered. And FIG.
As shown in (d), while the bottle Y is created from the preform X held by the holding mold 5a by the blow molding machine 2 according to the procedure described above, the holding mold 5b is used as a part of the mold. The injection molding machine 1 is used to newly create a preform X.

Next, the base 102 is raised, and as shown in FIG. 4E, the holding mold 5a is filled with the bottle Y and the holding mold 5b.
While the preforms X are held, the turntable 3 is rotated by 90 degrees, and the holding molds 5 a are conveyed so that the holding molds 5 a are arranged on the collection box 6. After the transportation, the holding mold 5a is opened to release the holding of the bottle Y. FIG. 5 is a diagram showing an aspect in which the holding mold 5 is opened. As a result, the bottle Y falls by its own weight and is collected in the collection box 6.

Finally, as shown in FIG. 4 (f), the holding mold 5a is closed and the turntable 3 is further rotated 90 degrees, so that the holding mold 5b holding the preform X is placed on the blow molding machine 2. ,
The holding molds 5a are arranged on the injection molding machine 1, respectively.
As a result, the turntable 3 has rotated once. After that, the bottle Y is continuously manufactured by repeating the same procedure. The manufactured bottles Y are successively collected by the collection box 6.

As described above, according to the present embodiment, the bottle Y by the holding metal fitting 5 is provided during the rotation of the turntable 3.
Since the holding of the bottle Y is released, the bottle Y can be collected only by preparing the collection box 6 without preparing a special device. Furthermore, since only two sets of holding dies 5 are used, the number of holding dies can be reduced. Therefore, the manufacturing apparatus A of the present embodiment can manufacture a hollow molded product with a relatively simple structure and with a smaller number of holding molds.

In the above embodiment, the rotary disk 3 is set to 90.
Although it is decided to rotate intermittently every one degree, the holding die 5 is stopped only on the injection molding machine 1 and the blow molding machine 2.
You may make it rotate intermittently every 80 degrees. In this case, the holding mold 5 does not stop on the collection box 6,
The holding of the bottle Y can be released while the holding die 5 holding the bottle Y is passing over the collection box 6.

[0035]

As described above, according to the present invention, it is possible to manufacture a hollow molded article with a relatively simple structure and with fewer holding dies.

[Brief description of drawings]

FIG. 1 is a schematic view showing a structure of a hollow molded article manufacturing apparatus A according to an embodiment of the present invention.

2A to 2C are diagrams showing a processing procedure of the injection molding machine 1. FIG.

3A and 3B are views showing a processing procedure of the blow molding machine 2.

FIGS. 3C and 3D are views showing a processing procedure of the blow molding machine 2. FIGS.

4 (a) to (f) are schematic diagrams showing each processing step in the manufacturing apparatus A. FIG.

FIG. 5 is a view showing a mode in which a holding die 5 is opened.

Claims (4)

[Claims] 1. An injection molding machine for producing a preform of a hollow molded article by injection molding, and a blow molding machine which is arranged so as to face the injection molding machine and produces a hollow molded article from the preform by blow molding. Two holding means that form part of a mold for injection molding by the injection molding machine, and that can hold the preform and the hollow molded product, and are rotatably provided around a predetermined rotation center. And a rotating plate that supports the two holding means in a state of being symmetrically arranged with respect to the rotation center and conveys the holding means between the injection molding machine and the blow molding machine by the rotation thereof. The holding means releases the holding of the hollow molded product produced by the blow molding machine during the transportation from the blow molding machine to the injection molding machine. Place 2. The turntable rotates intermittently by 90 degrees, and the holding means holds the hollow molded article and then is placed at a position of 90 degrees as viewed from the blow molding machine, 2. The holding of the hollow molded article is released.
An apparatus for producing a hollow molded article according to 1. 3. The hollow according to claim 1, wherein the hollow molded article is a bottle, and the holding means constitutes a mold of a neck portion of the bottle and holds the neck portion. Equipment for manufacturing molded products. 4. An injection molding machine, a blow molding machine arranged to face the injection molding machine, and a part of a mold for injection molding by the injection molding machine, and the injection molding machine and the injection molding machine. A method for manufacturing a hollow molded product, comprising: a holding device capable of holding a molded product created by a blow molding machine; and two holding devices that are symmetrically arranged about a predetermined rotation center. A step of creating a preform of a hollow molded product by a molding machine and one of the holding means, while holding the preform by the one holding means, by rotating the holding means around the rotation center, A step of conveying a preform to the blow molding machine, and a blow molding machine to form a hollow molded article from the preform held by the one holding means, while the injection is performed. A step of forming a preform of a hollow molded article by a shaping machine and the other holding means, holding the hollow molded article by the one holding means, while holding the preform by the other holding means, A step of releasing the holding of the hollow molded article by the one holding means during the rotation of the holding means while conveying the preform to the blow molding machine by rotating the holding means around the rotation center. And a method for producing a hollow molded article including.