JP2022092194A - Molding device - Google Patents

Abstract

To provide a molding device that can cut hollow molded products in the molding die while increasing the degree of freedom in the cutting direction.SOLUTION: A molding device in one embodiment includes a molding die including a first mold and a second mold that can be opened and closed, and forming a cavity between the first mold and the second mold; a parison supply section that supplies parison into the cavity; and a blowing section that forms the parison into a hollow molded product by expanding the parison in the cavity. The first passageway is formed in the interior of the first mold and the second passageway is formed in the interior of the second mold, and the first passageway and the second passageway are connected to each other and form a connecting passageway extending in a direction intersecting the parting surface of the mold when the first mold and the second mold are closed. The blade portion is configured to be movable along the extending direction of the connecting passageway.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a molding apparatus.

Conventionally, a molding apparatus for blow molding a hollow molded product by expanding a parison supplied to the inside of a cavity in a molding die is known. For example, in Patent Document 1 below, a parison is placed in a cavity formed in a pair of molds, the pair of molds is closed, and a compressed gas is blown into the parison to expand the parison to form a hollow molded product. Described is a molding apparatus that cuts an unnecessary part of a hollow molded product by forming and moving a cutting tool attached to one of the pair of dies along the parting surface of the pair of dies. There is.

Japanese Unexamined Patent Publication No. 2002-172684

In recent years, attempts have been made to form hollow molded products having a complicated two-dimensional shape or three-dimensional shape by blow molding. When producing such a hollow molded product, it is desirable that the hollow molded product can be cut not only from the direction perpendicular to the parting surface of the molding die but also from various directions. However, since the cutting tool described in Patent Document 1 is slid along a parallel direction along the parting surface of a pair of molds, there is a restriction on the cutting direction of the hollow molded product. For example, in order to cut a hollow molded product along a direction inclined with respect to the parting surface of a pair of molds, it is necessary to arrange the cutting tool at an angle to the parting surface. However, when the cutting tool is arranged so as to be inclined to the parting surface, the cutting tool and the mold interfere with each other, which hinders the opening and closing of the mold.

In view of the above problems, it is an object of the present disclosure to provide a molding apparatus capable of cutting a hollow molded product in a molding die while increasing the degree of freedom in the cutting direction.

In one aspect, a molding device for blow molding a hollow molded product is provided. This molding apparatus includes a first mold and a second mold that can be opened and closed, a molding mold that forms a cavity between the first mold and the second mold, and a parison supply that supplies a parison to the cavity. A portion, a blow portion for forming the parison into a hollow molded product by expanding the parison in the cavity, and a blade portion for cutting the hollow molded product in the molding die are provided, and the inside of the first mold is provided with a portion. A first passage communicating with the cavity is formed, a second passage communicating with the cavity is formed inside the second mold, and the first mold and the second mold are closed in the first passage and the second passage. In the squeezed state, a continuous passage is formed so as to communicate with each other and extend in a direction intersecting the parting surface of the molding die, and the blade portion is configured to be able to advance and retreat along the extending direction of the continuous passage. ing.

In this molding apparatus, the blade portion advances and retreats along a continuous passage extending in a direction intersecting the parting surface of the molding die. By advancing and retreating the blade portion in this way, it is possible to cut the hollow molded product in the molding die along the direction intersecting the parting surface. Further, in this molding apparatus, for example, even when the communication passage extends in a direction inclined with respect to the parting surface, the blade portion is retracted from the first passage or the second passage to form the blade portion. It is possible to prevent interference with the molding die. Therefore, according to this molding apparatus, it is possible to cut a hollow molded product in a molding die while increasing the degree of freedom in the cutting direction.

In one embodiment, the blade portion is formed with a through hole having a shape corresponding to the shape of the cavity, and the inner wall of the blade portion defining the through hole is formed with a cutting edge for cutting a hollow molded product. May be good. In this embodiment, the hollow molded product can be cut in the molding die by the cutting edge arranged so as to surround the hollow molded product by advancing and retreating the blade portion during blow molding.

In one embodiment, the first passage and the second passage may extend in a direction inclined with respect to the parting surface.

According to one aspect of the present invention and various embodiments, the hollow molded product can be cut in the molding die while increasing the degree of freedom in the cutting direction.

It is a side view which shows typically the molding apparatus which concerns on one Embodiment. It is a top view which shows the exemplary cutting mechanism. It is sectional drawing which shows the part of the molding apparatus which concerns on one Embodiment enlarged. It is sectional drawing which shows an example of the cutting method of a hollow molded article. It is a flowchart which shows the manufacturing method of the hollow molded article which concerns on one Embodiment. It is sectional drawing which shows another example of the cutting method of a hollow molded article.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following description, the same or equivalent elements are designated by the same reference numerals, and duplicate explanations will not be repeated. The dimensional ratios in the drawings do not always match those described.

FIG. 1 is a side view schematically showing a molding apparatus 1 according to an embodiment. This molding apparatus 1 molds the hollow molded product 100 by the suction blow method (see FIG. 4). In the following description, the hollow-shaped product molded by the molding apparatus 1 is referred to as a hollow molded product 100, and the material of the hollow molded product before the completion of molding is referred to as a parison 200. As shown in FIG. 1, the molding apparatus 1 includes a molding die 2, a drive mechanism 3, a parison supply unit 4, a suction unit 5, a blow unit 6, and a cutting mechanism 8.

The molding die 2 is a mold for molding the parison 200 into the hollow molded product 100, and includes a first mold 11 and a second mold 12 facing each other. The first mold 11 and the second mold 12 are composed of, for example, aluminum blocks, and form a pair of molds. The first mold 11 and the second mold 12 have a pair of molding surfaces 13 and 14, respectively.

The molding surface 13 of the first mold 11 includes a contact surface 13a and a recess 13b recessed with respect to the contact surface 13a. The molding surface 14 of the second mold 12 includes a contact surface 14a and a recess 14b recessed with respect to the contact surface 14a. The contact surface 13a and the contact surface 14a are surfaces that come into contact with each other when the first mold 11 and the second mold 12 are closed (mold closed state). That is, the contact surface 13a and the contact surface 14a form a parting surface P that divides the molding die 2. The first mold 11 and the second mold 12 form a cavity 15 between the recess 13b and the recess 14b, which is a space having a shape corresponding to the outer shape of the hollow molded product 100 when the mold is closed.

The drive mechanism 3 moves at least one of the first mold 11 and the second mold 12. The drive mechanism 3 applies a driving force to at least one of the first mold 11 and the second mold 12, and slides the first mold 11 and the second mold 12 in the direction toward and away from each other (face-to-face direction). Let me. For example, the drive mechanism 3 moves the first mold 11 and the second mold 12 in a direction approaching each other at the time of supplying the parison 200 and at the time of blow molding to close the molding mold 2. On the other hand, when the hollow molded product 100 is taken out, the drive mechanism 3 moves the first mold 11 and the second mold 12 in a direction away from each other to open the molding mold 2. The drive mechanism 3 may move one of the first mold 11 and the second mold 12 in the facing direction, or move both the first mold 11 and the second mold 12 in the facing direction. You may.

The parison supply unit 4 supplies the parison 200, which is the material of the hollow molded product 100, to the molding die 2. The parison supply unit 4 is provided above, for example, the molding die 2, and the molten resin material is formed into a substantially cylindrical shape and discharged as the parison 200. The discharged parison 200 is introduced into the cavity 15 from the charging port 15a of the molding die 2. The suction portion 5 guides the parison 200 from the charging port 15a of the molding die 2 to the suction port 15b by sucking the air inside the cavity 15 from the suction port 15b formed on the opposite side of the charging port 15a when the parison 200 is supplied. ..

The material of the parison 200 supplied from the parison supply unit 4 is, for example, PP (polypropylene), PE (polyamide), PA6 (polyamide 6), PA66 (polyamide 66), PA610 (polyamide 610), PA12 (polyamide 12). ), PA612 (polyamide 612), PPS (polyphenylene sulfide resin), PBT (polybutylene terephthalate resin), TPEE (polyester thermoplastic elastomer). The parison 200 may contain an additive such as glass or a strengthening agent.

The blow unit 6 supplies a high-pressure fluid into the parison 200 held between the first mold 11 and the second mold 12. For example, the blow section 6 has an air supply section 6a for supplying compressed air, and closing sections 6b and 6c for closing both ends of the parison 200. For example, the blow section 6 supplies compressed air from the air supply section 6a to the inside of the parison 200 whose ends are blocked by the closing sections 6b and 6c to expand the parison 200. The parison 200 expanded by the supply of compressed air is pressed against the surfaces of the recesses 13b and 14b that define the cavity 15, so that the parison 200 is formed into a hollow molded product 100 having a shape corresponding to the cavity 15.

The cutting mechanism 8 cuts the hollow molded product 100 inside the molding die 2. The cutting mechanism 8 includes a blade portion 21 and a driving portion 22, and is fixed to the first mold 11 by, for example, a frame member or the like. FIG. 2 is a plan view showing an exemplary cutting mechanism 8. The blade portion 21 is a substantially rectangular plate member, and is made of, for example, a hardened steel material. A through hole 21h that penetrates the blade portion 21 in the plate thickness direction is formed in the vicinity of the tip portion of the blade portion 21. The planar shape of the through hole 21h matches, for example, the cross-sectional shape of the cavity 15. For example, when the hollow molded product 100 formed in the cavity 15 has a cylindrical shape, the through hole 21h has a circular planar shape as shown in FIG.

The through hole 21h is arranged so as to overlap the cavity 15 when viewed from the extending direction of the cavity 15 during supply and blow molding of the parison 200. That is, the inner wall surface 21a of the blade portion 21 defining the through hole 21h forms the cavity 15 together with the recess 13b of the first mold 11 and the recess 14b of the second mold 12 when the parison 200 is supplied and blow molded. .. Therefore, the inner wall surface 21a of the blade portion 21 is arranged so as to surround the outer periphery of the hollow molded product 100 during blow molding.

A cutting edge 21b for cutting the hollow molded product 100 is formed on the inner wall surface 21a of the blade portion 21. The cutting edge 21b may be formed over the entire circumference of the inner wall surface 21a, or may be formed on a part of the inner wall surface 21a.

The drive unit 22 is connected to the blade unit 21 via the arm member 24. The drive unit 22 is an actuator such as a hydraulic cylinder, an electric cylinder, or an air cylinder, and generates a driving force for moving the blade unit in the extending direction of the arm member 24. In the example shown in FIG. 1, the cutting mechanism 8 is attached to the upper part of the first mold 11, but in one embodiment, the molding apparatus 1 has a plurality of cutting mechanisms 8 and these plurality of cutting mechanisms. 8 may be attached to the upper part and the lower part of the molding die 2.

As shown in FIG. 1, in one embodiment, the molding device 1 may further include a control device 30. The control device 30 is a computer including a processor, a storage unit, an input device, a display device, and the like, and controls each part of the molding device 1. In the control device 30, the operator can perform a command input operation or the like in order to manage the molding device 1 by using the input device, and the display device visualizes and displays the operating status of the molding device 1. be able to. In the storage unit of the control device 30, a control program for controlling various processes executed by the molding device 1 by the processor and a program for causing each component unit of the molding device 1 to execute the processes according to the processing conditions are stored. Stored.

For example, the control device 30 is communicably connected to the drive mechanism 3, the parison supply unit 4, the suction unit 5, the blow unit 6, and the cutting mechanism 8. The control device 30 sends a control signal to the drive mechanism 3, the parison supply unit 4, the suction unit 5, the blow unit 6, and the cutting mechanism 8, and opens and closes the molding die 2, operates the parison supply unit 4, and sucks. It controls the operation of 5, the operation of the blow unit 6, and the operation of the blade unit 21.

Hereinafter, the molding die 2 and the cutting mechanism 8 will be described in more detail with reference to FIG. FIG. 3 is a schematic cross-sectional view showing a part of the molding apparatus 1 in an enlarged manner. As shown in FIG. 3, inside the first mold 11, a first passage that communicates with the cavity 15 and extends in a direction (direction intersecting) perpendicular to the parting surface P of the molding mold 2. 11p is formed. Inside the second mold 12, a second passage 12p that communicates with the cavity 15 and extends in a direction perpendicular to the parting surface P of the molding mold 2 is formed. These first passage 11p and second passage 12p form a communication passage 25 that communicates with each other and extends in a direction perpendicular to the parting surface P (direction intersecting) when the molding die 2 is in the mold closed state. do.

A blade portion 21 is arranged inside the communication passage 25. The blade portion 21 advances and retreats along the extending direction of the communication passage 25 by the driving force of the drive portion 22, so that the position where the cavity 15 and the through hole 21h communicate with each other and the through hole 21h are in the first passage 11p. It is movable between the position where it is arranged and the position where the through hole 21h is arranged in the second passage 12p. Further, the blade portion 21 can be retracted to a position retracted from the second passage 12p.

The arrangement position of the blade portion 21 in the communication passage 25 is controlled by the control device 30. For example, as shown in FIG. 4A, at the time of supplying the parison 200 and at the time of blow molding, the control device 30 arranges the blade portion 21 at a position where the cavity 15 and the through hole 21h communicate with each other. Then, as shown in FIG. 4B, the control device 30 has a blade at a position where the through hole 21h is arranged inside the first passage 11p after blow molding, that is, at a position where the cavity 15 and the through hole 21h do not communicate with each other. Retreat the unit 21. As a result, the cutting edge 21b crosses the inside of the cavity 15, and the unnecessary portion 100a is cut off from the hollow molded product 100 molded in the cavity 15. The control device 30 may advance the blade portion 21 so that the through hole 21h is arranged inside the second passage 12p after blow molding to cut off the unnecessary portion 100a from the hollow molded product 100.

Hereinafter, a method for manufacturing the hollow molded product 100 using the above-mentioned molding apparatus 1 will be described. FIG. 5 is a flowchart showing a method for manufacturing a hollow molded product according to an embodiment. In this method, the cavity 15 is formed between the first mold 11 and the second mold 12 by first closing the molding die 2 by the drive mechanism 3 (step ST1). Next, as shown in FIG. 4A, the position of the blade portion 21 is adjusted so that the through hole 21h is arranged on the cavity 15 (step ST2).

Next, the parison 200 is supplied from the parison supply unit 4 into the cavity 15 (step ST3). At this time, the inside of the cavity 15 is sucked by the suction portion 5, so that the parison 200 is guided to the suction port 15b of the molding die 2. Next, compressed air is supplied to the inside of the parison 200 by the blow portion 6, so that the parison 200 is blow-molded into the hollow molded product 100 (step ST4).

Next, as shown in FIG. 4B, the blade portion 21 is moved in the extending direction of the communication passage 25 by the drive portion 22, so that the unnecessary portion 100a of the hollow molded product 100 is cut (step ST5). ). In the example of FIG. 4B, the hollow molded product 100 is cut by retracting the blade portion 21 toward the first mold 11, but the blade portion 21 is advanced toward the second mold 12. This may cut the hollow molded product 100.

Next, the drive mechanism 3 opens the molding die 2, so that the first mold 11 and the second mold 12 are separated from each other (step ST6). As a result, the hollow molded product 100 from which the unnecessary portion 100a is cut is taken out from the molding die 2.

According to the manufacturing method of the hollow molded product 100 described above, since the unnecessary portion 100a is cut from the hollow molded product 100 in the molding die 2 by the cutting mechanism 8, the unnecessary portion 100a is removed after the hollow molded product 100 is taken out. It is possible to omit the step of cutting separately. Therefore, the productivity of the hollow molded product 100 can be improved.

Next, another embodiment of the molding apparatus will be described. As shown in FIG. 6A, in the molding die 2 according to another embodiment, the cavity 15 extends in a direction inclined with respect to the parting surface P of the molding die 2. Therefore, in the cavity 15, the hollow molded product 100 extending in the direction inclined toward the parting surface P of the molding die 2 is molded.

In this embodiment, the first passage 11p formed in the first mold 11 is inclined in a direction perpendicular to the extending direction of the hollow molded product 100, that is, with respect to the parting surface P of the molding mold 2. It extends in the direction. Similarly, the second passage 12p formed in the second mold 12 is in a direction perpendicular to the extending direction of the hollow molded product 100, that is, in a direction inclined with respect to the parting surface P of the molding mold 2. It is postponed. The first passage 11p and the second passage 12p communicate with each other when the molding die 2 is closed, and form a communication passage 25 extending in a direction intersecting the parting surface P.

The arrangement position of the blade portion 21 in the communication passage 25 is controlled by the control device 30. For example, as shown in FIG. 6A, at the time of supplying the parison 200 and at the time of blow molding, the control device 30 arranges the blade portion 21 at a position where the cavity 15 and the through hole 21h communicate with each other. Then, as shown in FIG. 6B, the control device 30 retracts the blade portion 21 toward the first mold 11 side along the extending direction of the communication passage 25 after blow molding. At this time, the blade portion 21 is retracted so as to be retracted from the second passage 12p. As a result, the cutting edge 21b crosses the inside of the cavity 15, and the unnecessary portion 100a is cut off from the hollow molded product 100 molded in the cavity 15.

After cutting the hollow molded product 100, the first mold 11 and the second mold 12 are opened by the drive mechanism 3, and the hollow molded product 100 from which the unnecessary portion 100a is cut is taken out from the molding mold 2. At this time, since the blade portion 21 is retracted from the second passage 12p of the second mold 12, interference between the blade portion 21 and the molding die 2 is prevented. Therefore, according to this molding apparatus 1, the degree of freedom in the cutting direction of the hollow molded product 100 can be increased.

Although the molding apparatus 1 according to various embodiments has been described above, various modifications can be configured without being limited to the above-described embodiment without changing the gist of the invention. For example, the above-mentioned first mold 11 and second mold 12 are configured to open and close in the horizontal direction, while the first mold 11 and the second mold 12 are configured to open and close in the vertical direction. You may be. Further, the cavity 15 may have a curved shape in the extending direction thereof.

1 ... molding device, 2 ... molding die, 4 ... parison supply section, 6 ... blow section, 11 ... first mold, 11p ... first passage, 12 ... second mold, 12p ... second passage, 15 ... Cavity, 21 ... Blade part, 21b ... Cutting edge, 21h ... Through hole, 25 ... Communication passage, 100 ... Hollow molded product, 200 ... Parison, P ... Parting surface.

Claims (3)

A molding device that blow-molds hollow molded products.
A molding die that includes a first mold and a second mold that can be opened and closed, and that forms a cavity between the first mold and the second mold.
A parison supply unit that supplies parison to the cavity,
A blow portion that forms the parison into the hollow molded product by expanding the parison in the cavity.
A blade portion for cutting the hollow molded product in the molding die,
Equipped with
A first passage communicating with the cavity is formed inside the first mold.
A second passage communicating with the cavity is formed inside the second mold.
The first passage and the second passage extend in a direction in which the first mold and the second mold communicate with each other and intersect the parting surface of the molding mold when the first mold and the second mold are closed. Form a communication passage to
The blade portion is a molding apparatus configured to be able to advance and retreat along the extending direction of the communication passage. A through hole having a shape corresponding to the shape of the cavity is formed in the blade portion.
The molding apparatus according to claim 1, wherein a cutting edge for cutting the hollow molded product is formed on the inner wall of the blade portion that defines the through hole. The molding apparatus according to claim 1 or 2, wherein the first passage and the second passage extend in a direction inclined with respect to the parting surface.

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