JP3096346B2 - Molding apparatus and method for producing molded article using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding apparatus and a molding method useful for obtaining a molded article having a hinge.

[0002]

2. Description of the Related Art A wide variety of plastic molded articles are manufactured by using an injection molding apparatus or the like. Such a molded product is usually manufactured using a mold composed of a fixed mold and a movable mold, a split mold composed of a convex mold and a concave mold, and the like.

On the other hand, air-conditioning ducts for automobiles and the like include Y
Usually, a damper is used to switch a flow path such as a letter shape. This damper, as shown in FIG.
It is composed of an iron plate 21, a hinge part 22 and a seal part 23. The damper having such a structure is a stamped iron plate 2
After spot welding the hinge part 22 to 1 and surface-treating it,
It is manufactured by placing it in a mold and baking nitrile rubber or the like on the peripheral portion of the iron plate 21 excluding the hinge portion to form the seal portion 23. Further, in order to enhance the integrity of the iron plate 21 and the seal portion 23, a large number of holes 24 buried with the rubber are formed in the peripheral portion of the iron plate 21.

[0004] Since such a damper uses the iron plate 21, the weight is large and the load required for switching the flow path is large. Further, not only is it easy to corrode, but also the price is high. Furthermore, although the iron plate 21 is excellent in heat resistance,
The heat resistance of the seal portion 23 necessary for keeping the flow path airtight is not so high. Therefore, the quality of the damper for air conditioning is excessive. Therefore, by injection molding, etc.
It would be useful to form the damper with flat plastic instead of the iron plate 21.

[0005] However, when manufacturing a molded product in which a plurality of parts are made of plastic, rubber, or the like having different materials, for example, a damper having the above structure using the above-described mold, the operation becomes complicated. , Reducing productivity. That is, when manufacturing such a molded product, using a molding device having a mold as described above, a primary molding step of molding a primary molded product made of plastic, the primary molded product from the mold A take-out process, a mounting process of mounting the taken-out primary molded product in another mold, and a secondary molding process of molding a secondary molded portion made of rubber or the like are required. In particular, in the case where secondary molded portions are formed on both surfaces of a primary molded product such as a flat plate, workability and productivity are further reduced.

Japanese Unexamined Patent Publication No. Hei 3-2015 discloses a method of manufacturing a damper having a flap having a pivot formed in the center and extending on both sides of the pivot. A method of forming a soft resin seal lip protruding to the front side and the back side to one side is disclosed. In this method, in the step of molding the flap main body, a first mold having a first cavity for forming a first seal lip portion is used,
After closing the cavity with a second mold and injecting a hard resin to form a flap body, after releasing the second mold, a second cavity for forming a second seal lip is formed. The third mold and the first mold are combined, and a soft resin is injected into the first and second cavities to form a seal lip.

However, in the above-mentioned method, the seal wrap portions can be formed only on both peripheral edges of the flap main body. That is, even if an attempt is made to form a secondary molded portion at the center of the flap main body, the first cavity formed in the first mold is closed by the flap main body. The next molded part cannot be formed. Further, for the same reason, seal lip portions cannot be formed at appropriate positions on both surfaces of the flap body. Therefore, the use of the molded article is limited.

Accordingly, it is an object of the present invention to efficiently form a secondary molded part having a material different from that of the primary molded product in a proper position on the front and back portions of the primary molded product, and to improve workability and productivity of the molded product. It is an object of the present invention to provide a molding device and a molding method that can be used.

[0009]

In order to achieve the above object, the present inventor has proposed that a molded product having a hinge portion is
Focusing on the fact that the hinge portion can be inverted on the molding die with the center axis as a result, as a result of intensive studies, the mold is formed with a primary molding region in one region with the hinge portion as the central axis, and the other region, namely, the molding Using a mold in which a secondary molding area having a cavity in the inversion area where the article is inverted and a mold in which a cavity is formed in an area corresponding to the secondary molding area, a primary molded article was molded in the primary molding area. Thereafter, it was found that when the primary molded product was turned over and molded in the secondary molding region of the mold, secondary forming portions could be formed on both surfaces of the primary molded product, and the present invention was completed.

[0010] That is, the present invention is a molding apparatus provided with a mold for forming a secondary molded portion on both sides of a primary molded product having a hinge portion, wherein the primary molded product is reversed around the hinge portion as a central axis. While having a mechanism, the mold,
A primary mold region is formed on one side with the hinge portion as a central axis, and a secondary mold region having a cavity on the other side is formed, and the mold is moved forward and backward relative to the mold. A molding die having a cavity in a region corresponding to the secondary molding region, and a gate for supplying a primary molding resin to the primary molding region is formed in one of the molding dies; Provided is a molding device in which a gate for supplying a secondary molding resin to a secondary molding region is formed on one of the molds.

The present invention also provides a molding method using the molding device. This molding method is a method of forming a secondary molded portion on both surfaces of a primary molded product having a hinge portion by using a molding device equipped with a mold, wherein the primary portion is formed on one side with the hinge portion as a central axis. A molding region is formed, and a molding die formed with a molding die having a secondary molding region having a cavity on the other side, and a molding die that moves forward and backward relative to the molding die. In the primary molding region of the molding die, after supplying a primary molding resin to form a primary molded product having a hinge portion, the primary molded product is inverted around the hinge portion as a central axis, and the secondary molding region of each of the molding dies is formed. , A secondary molding resin is supplied to form a secondary molded part on both surfaces of the primary molded product.

The present invention is characterized in that a primary molded product is inverted on a molding die with a hinge portion as a central axis, a secondary molding region of one die, and a region of the other die corresponding to the secondary molding region. ,
Each of them has a feature in that cavities for forming secondary molded portions are formed on both surfaces of the primary molded product.

Therefore, in the molding apparatus and the molding method, the primary molding resin is supplied in the primary molding region to form the primary molded product, and then the primary molded product is turned over, and the secondary molding is performed in the secondary molding region of the mold. By supplying the molding resin and performing the secondary molding, it is possible to manufacture a molded product having a hinge portion and having the secondary molded portions formed on both surfaces of the primary molded product. Therefore, the removal process for removing the primary molded product from the mold, which was conventionally required,
The mounting step of mounting the primary molded product in another mold is not required. Further, since the cavity for forming the secondary molded portion is formed in the secondary molded region, the secondary molded portion can be smoothly formed at an appropriate position on both surfaces of the primary molded product.

In the above molding apparatus, the mold is formed with a rotatable and positionable molding die, and a gate for moving the resin forward and backward relative to the molding die and supplying a primary molding resin. At least one primary molding die, and at least one secondary molding die that moves forward and backward relative to the rotated molding die and has a gate formed for supplying a secondary molding resin. May be.

In the above molding method, a primary mold having a hinge portion is provided by using a mold that is rotatable and positionable and at least one primary mold having a gate for supplying a primary molding resin. After molding the molded product, the primary molded product is turned around the hinge portion as a central axis, and the molding die is rotated and positioned, and the rotatable molding die and a gate for supplying the secondary molding resin are provided. And at least one secondary mold in which
Secondary moldings may be formed on both surfaces of the primary molding.

In such a molding apparatus and a molding method, after a primary molded product is produced by using a rotatable molding die and a primary molding die, the molding die is rotated by a predetermined angle, and the molding die and the secondary molding die are rotated by a predetermined angle. The next molded part can be formed. Therefore, the molded product can be continuously and efficiently manufactured by the rotation of the primary molded product and the rotation of the mold with the hinge portion as the central axis.

Further, it is preferable that the primary molding resin is harder than the secondary molding resin. In this case, the mechanical strength of the molded product can be ensured by the primary molded product.

[0018]

Embodiments of the present invention will be described below in more detail with reference to the accompanying drawings.

FIGS. 1 to 3 are schematic sectional views for explaining the operation of a molding apparatus according to one embodiment of the present invention. In this example, an apparatus for forming a damper is shown. FIG. 4 is a perspective view showing a primary molded product obtained by the molding method of the present invention, and FIG. 5 is a perspective view showing a secondary molded product obtained by the molding method of the present invention.

The molding apparatus 1 has molding dies 4a and 4b formed on both sides of a reversing plate 3 that can be reversed about a shaft 2. These molds 4 a and 4 b are inverted with the reversal of the reversing plate 3.

In both molds 4a and 4b, a primary molding region 5a is formed in one region and a secondary molding region 5b is formed in the other region around an axis corresponding to the shaft 2. . More specifically, both forming dies 4a and 4b are provided with hinge forming pins 6 corresponding to the axis of the shaft 2 and concave portions 7 for forming hinge portions 14.
Are formed. The hinge forming pin 6 is rotatable to reverse the primary molded product 13. A pin 8 for forming a plurality of holes 15 in a peripheral portion of a flat primary molded product 13 protrudes from a primary molding region 5a extending around the hinge forming pin 6. In addition, the secondary molding area 5
b has a cavity 9a for secondary molding.

On one side of the molding die 4a, there is a molding die 4a.
The primary molding die 10a which moves forward and backward facing the molding surface is provided. This molding die 10a constitutes a movable die. Also, a primary molding die 10a corresponding to the primary molding region 5a
The cavity 11 for forming the primary molded product 13 is formed on the molding surface of the first embodiment. Further, a gate 12a for supplying a hard thermoplastic resin for primary molding is formed in the primary molding die 10a.

A secondary molding die 10b is provided on the side of the other molding die 4b so as to be able to advance and retreat similarly to the primary molding die 10a. On the molding surface of the secondary molding die 10b corresponding to the secondary molding region 5b, a cavity 9b for forming the secondary molding part 17 in the primary molding 13 and forming the secondary molding 16 is formed. I have. In this example, the cavity 9b is formed in a symmetrical cross section with the cavity 9a of the mold 4b. In addition, in the secondary forming die 10b,
A gate 12b for supplying a soft thermoplastic resin for secondary molding, for example, a thermoplastic elastomer, to the cavities 9a and 9b is molded.

In this example, the soft thermoplastic resin constituting the secondary molded portion 17 is supplied to the peripheral portion of the primary molded product 13 excluding the hinge portion 14.

Further, the molding device 1 converts the secondary molded product 16 molded in the secondary molding region 5b into a molding die 4b, 1
It has a rod 18 for taking it out of Ob. The rod 18 normally moves forward and backward by hydraulic pressure or pneumatic pressure in conjunction with mold clamping and mold opening between the molding die 4b and the secondary molding die 10b. Also, with the return movement of the rod 18, the hinge forming pin 6 slides and moves in the axial direction. For this reason, the undercut portion of the hinge portion 14 comes out of the mold 4b smoothly.

The molding method using such a molding apparatus is as follows.

That is, as shown in FIG. 1, a hinge forming pin 6 is provided between one reversible molding die 4a and a primary molding die 10a, and the mold is clamped to form a primary molding die 10a. A hard thermoplastic resin is supplied to the cavity 11 from the gate 12a. The thermoplastic resin is usually supplied by being melted by an extruder. By supplying the molten thermoplastic resin, a hinge portion 14 is formed around the pin 6, and a flat primary molded article 13 having a hole 15 corresponding to the projecting pin 8 is formed. (FIG. 4
reference).

After the primary molded article 13 is cooled and opened,
With the rotation of the hinge forming pin 6, the hinge portion 14
The primary molded article 13 is inverted around the center axis, and the mold 4a is also inverted. As shown in FIG. 2, with this operation, the primary molded product 13 moves to the secondary molding region 5b of the one molding die 4a and the one molding die 4a
Faces the secondary mold 10b, and the other mold 4b faces the primary mold 10a.

Then, one molding die 4a and the secondary molding die 1
0b and mold, and melted soft thermoplastic resin,
The secondary molding in which the secondary molding 17 is formed on both sides of the primary molding 13 by supplying from the gate 12b and forming the secondary molding 17 on the periphery of the primary molding 13 except for the hinge 14 The product 16 is formed (see FIG. 5). Also, the other molding die 4b and the primary molding die 10a are clamped, and the molten hard thermoplastic resin is supplied from the gate 12a to form the primary molded product 13.

In conjunction with the opening of the molding die 4a and the secondary molding die 10b, the secondary molded product 16 is pushed out of the molding die 4a by the rod 18, and the hinge forming pin 6 is moved. As a result, it is taken out of the mold 4a and commercialized. On the other hand, the primary molded product 13 is inverted around the hinge portion 14 as a center axis and moves to the secondary molding region 5b in the same manner as described above, and the molding die 4b is
In the same manner as described above, a secondary molded product 16 having secondary molded portions 17 formed on both surfaces of the primary molded product 13 is molded.

Therefore, according to the molding apparatus and the molding method, the secondary molding in which the secondary molding portions 17 are formed on both surfaces of the primary molded product 13 by reversing the molding dies 4a and 4b and reversing the primary molded product 13. The article 16 can be manufactured continuously, and there is no need to take out the primary molded article 13 from the molds 4a and 4b and perform secondary molding using another mold. for that reason,
Despite being composed of a plurality of thermoplastic resins, the productivity of the secondary molded product 16 can be significantly increased.

The molding apparatus and the molding method of the present invention can be applied not only to the damper but also to various molded products as long as the secondary molded portion is formed on the primary molded product having a hinge portion. Further, the molded product is not limited to a flat molded product having a hinge portion, and can be applied to, for example, a bulged molded product having a hinge portion.

Further, the secondary forming portion is not limited to the peripheral portion of the primary molded product, and may be formed at an appropriate position on both sides. The secondary forming portion is formed partially or entirely on the front and back surfaces of the primary molded product. May be. In order to form a secondary forming portion on both surfaces of the primary molded product except for the hinge portion, a convex portion that contacts at the base side of the hinge portion of the primary molded product is formed in the primary molding die and the secondary molding die, and then molded. The secondary molding may be performed with the part of the primary molded product excluding the hinge part floating from the mold.

The molding dies are not limited to the reversible molding dies and the pair of molding dies as in the above-described embodiment. The molding dies can be rotated and positioned, at least one primary molding die, and at least one primary molding die. And two secondary molds.
Further, the rotatable mold is provided with one as in the above embodiment.
It is preferable that the rotation is not limited to every 80 ° but is sequentially performed at equal angles, such as 60 ° and 90 °, and positioning can be performed at even-numbered positions. When using such a mold, a plurality of primary molds and a plurality of secondary molds may be moved forward and backward with respect to the mold rotated and positioned at a predetermined angle.

As shown in FIGS. 1 to 3, the preferred molding apparatus includes a reversible molding die having molding dies 4a and 4b on both sides, a primary molding die 10a and a secondary molding die 10b. However, it is not necessary to have a reversible mold having the molds 4a and 4b on both sides, and the mold having the primary molding region and the secondary molding region may not be reversed. , May be fixed. That is, for example,
In the apparatus shown in FIG. 2, even if only the fixed molding die 4a is provided, after the primary molding is performed by the primary molding die 10a, the primary molding die 10a is opened and moved, and the primary molded product is subjected to the secondary molding. Area and the secondary mold 10
The secondary molding may be performed by moving b to the secondary molding area of the molding die 4a.

The molding die is composed of a mold having a primary molding region and a secondary molding region formed on both sides around a hinge portion of the primary molded product as a central axis, and a mold that moves forward and backward with respect to the mold. Any shape can be used as long as it can be sequentially molded. For example, in the apparatus shown in FIG. 2, the primary molding region 5a and the secondary molding region 5b
After the primary molded product molded by one molding die 4a having the above-described shape and one primary molding die 10a is inverted to the secondary molding region, the secondary molding region is formed in the region corresponding to the secondary molding region 5b. Secondary molding can also be performed by the primary molding die 10a in which a gate for supplying resin is formed.

Further, in order to form the secondary molded portions on both surfaces of the primary molded product, it is sufficient that cavities are formed in the secondary molded region of one mold and the secondary molded region of the other mold. The shape of the cavity can be selected according to the use as long as the mold can be opened.

The molding die and the primary molding die and / or the secondary molding die may be moved forward and backward relatively. However, in order to simplify the structure and increase the productivity, the primary molding region and the secondary molding region are formed. Preferably, the mold is fixed or rotatable.

The primary molded product may be inverted manually by using the hinge portion as a center axis. In addition, the reversing mechanism for reversing the primary molded product with the hinge portion as the central axis, for example,
The hinge portion forming pin has an uneven portion that extends in the axial direction and can be extracted from the hinge portion of the secondary molded product, and a mechanism that inverts the hinge portion forming pin by using the uneven portion. There may be.

The gate for supplying the primary molding resin or the secondary molding resin is not limited to one of the molding dies, for example, the primary molding dies and the secondary molding dies. Although it may be formed, it is preferably formed in another mold that moves with respect to one mold.

As the resin for the primary molding and the resin for the secondary molding, various molding materials, for example, styrene-based polymers,
Examples thereof include hard resins such as polycarbonate, polypropylene, and hard thermoplastic elastomers (for example, styrene-based elastomers, olefin-based elastomers, and polyester-based elastomers); olefin-based polymers such as polyethylene; and soft resins such as thermoplastic elastomers and rubbers. The type is not particularly limited as long as different types of primary molding resin and secondary molding resin are used.

As the primary molding resin, it is not necessary to use a harder material than the secondary molding resin. However, in order to secure mechanical strength and rigidity by the primary molding resin, the primary molding resin is harder than the secondary molding resin. Hard, especially rigid and tough resins are frequently used.

The primary molding resin and the secondary molding resin may be colored in the same or different colors as required. In the case of using resins colored in different colors, molded products colored in a plurality of colors can be manufactured.

In order to increase the molding accuracy, it is preferable that the resin for the primary molding be supplied at a higher temperature than the resin for the secondary molding and molded.

[0045]

According to the molding apparatus and the molding method of the present invention, a primary molded product is molded in a primary molding region of a mold, and is inverted around a hinge portion as a center axis, and a primary molded product is formed in a secondary forming region. Secondary molded parts can be formed on both sides. Therefore, a secondary molded part having a material different from that of the primary molded product can be efficiently formed at an appropriate position on the front and back portions of the primary molded product, and workability and productivity of the molded product can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional configuration diagram for explaining an operation of a molding apparatus according to one embodiment of the present invention, and shows a state immediately after a primary molding die is opened.

FIG. 2 is a schematic cross-sectional configuration diagram for explaining an operation of the molding apparatus according to one embodiment of the present invention, and shows a state where a primary molding die is opened.

FIG. 3 is a schematic cross-sectional configuration diagram for explaining an operation of the molding apparatus according to one embodiment of the present invention, and shows a state where a secondary molding die is opened.

FIG. 4 is a perspective view showing a primary molded product obtained by the molding method of the present invention.

FIG. 5 is a perspective view showing a damper as a secondary molded product obtained by the molding method of the present invention.

FIG. 6 is a schematic perspective view showing a conventional damper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Molding apparatus 4a, 4b ... Mold 5a ... Primary molding area 5b ... Secondary molding area 6 ... Pin for forming a hinge part 9a, 9b, 11 ... Cavity 10a ... Primary molding die 10b ... Secondary molding die 12a, 12b ... Gate 13: Primary molded product 14: Hinge part 16: Secondary molded product 17: Secondary molded part

Continued on the front page (51) Int.Cl. ⁷ Identification code FI B29L 31:22

Claims (5)

(57) [Claims] 1. A molding apparatus having a mold for forming a secondary molded portion on both sides of a primary molded product having a hinge portion, comprising a reversing mechanism for reversing the primary molded product around the hinge portion as a central axis. Along with the mold, a molding die in which a primary molding region is formed on one side with the hinge portion as a central axis, and a secondary molding region having a cavity on the other side, And a mold having a cavity in a region corresponding to the secondary molding region, and to supply the primary molding resin to the primary molding region to one of the molds. And a gate for supplying a resin for secondary molding to a secondary molding region is formed on one of the molding dies. 2. A mold, comprising: a mold capable of rotating and positioning; and at least one mold having a gate for supplying a primary molding resin, the mold moving forward and backward relative to the mold. Claims: 1. A mold comprising at least one primary molding die and at least one secondary molding die which moves forward and backward relative to the rotated molding die and has a gate formed for supplying a secondary molding resin. Item 6. The molding device according to Item 1. 3. A method for forming a secondary molded portion on both surfaces of a primary molded product having a hinge portion by using a molding device having a mold, wherein the primary molded portion is formed on one side with the hinge portion as a central axis. A molding region is formed, and a molding die formed with a molding die having a secondary molding region having a cavity on the other side, and a molding die that moves forward and backward relative to the molding die. In the primary molding region of the mold, after supplying the primary molding resin to form a primary molded product having a hinge portion,
A molding method in which a primary molded product is reversed around a hinge portion as a central axis, and a secondary molding resin is supplied in a secondary molding region of each of the molding dies to form secondary molded portions on both surfaces of the primary molded product. 4. A primary molded article having a hinge portion is molded by using a rotatable and positionable mold and at least one primary mold having a gate for supplying a primary molding resin. After that, while the primary molded product is inverted around the hinge portion as a central axis, the molding die is rotated and positioned, and at least a gate for supplying the rotatable molding die and the secondary molding resin is formed. The molding method according to claim 3, wherein secondary molding portions are molded on both surfaces of the primary molded product using one secondary molding die. 5. The molding method according to claim 3, wherein a primary molding resin harder than the secondary molding resin is used.