JP2003305726A - Mold for manufacturing multilayered molded object and manufacturing method for multilayered molded object using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold capable of manufacturing a multilayered molded object efficiently and safely in spite of a simplified mechanism. <P>SOLUTION: When a cavity surface of a mold positioned on the back side of skin materials is divided into one side and other side at the boundary part of first and second skin materials, a holding piece housing part for fitting in a holding piece on one side is formed while a skin contact part for holding the boundary part of the skin materials and a resin inflow part for housing a molten resin to fix the boundary part are respectively formed to the holding piece on the other side and the holding piece on one side. Then, the holding piece is projected into a cavity from the holding piece housing part. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold useful for producing a multilayer molded article in which a skin material is laminated on a thermoplastic resin substrate, and a method for producing a multilayer molded article using the same. It is a thing.

[0002]

2. Description of the Related Art A multi-layered molded product in which a surface material is laminated on a surface of a base material formed of a thermoplastic resin, particularly a molded product in which a plurality of skin materials are bonded, can effectively decorate the surface of the base material. For automobile interior parts (eg door trim,
It is widely used in a wide range of fields, including interior and exterior parts for home appliances and instrument panels).

The above-mentioned multilayer molded article is, for example, a method of supplying molten resin to the back side of a single skin material and molding it while bonding the skin material and the resin (injection molding method, compression molding method, etc.).
It is manufactured by manufacturing two multilayer molded bodies by the method and joining the multilayer molded bodies in the plane direction by heat fusion or the like. However, in such a manufacturing method,
The strength of the joint between the base materials may be insufficient.

As a method for solving such a problem, for example, a sandwiching body is used to sandwich the boundary between two skin materials,
A method is known in which this sandwich is embedded in the cavity surface of a mold, a molten resin is supplied from the mold, and molding is performed while the skin material and the resin are bonded together (JP-A-2-117511).
Issue Bulletin). FIG. 21 is a schematic sectional view for explaining the manufacturing method. As shown in FIG. 21A, a pair of male and female dies is used in the manufacturing method. Then, the first and second skin materials 1 and 2 are adjacent to each other in the plane direction, and the boundary portion 3 is sandwiched by a sandwiching body 30 composed of a pair of sandwiching pieces 30a, 30b. Is embedded in the cavity surface of the male mold 14. After being embedded, the first formed on the male mold 14
The molten thermoplastic resin 21 is supplied from the gate 11 to the back surface of the first skin material 1, and the molten thermoplastic resin 22 is supplied from the second gate 12 to the back surface of the second skin material 2. 1
The molded body is manufactured by pressing the resin with 5 and the male mold 14 (see FIG. 21B). According to this method, the base materials can be firmly bonded to each other, but the sandwiching body must be manually attached and detached, and there is a problem that the work efficiency is poor. In addition, when the molded body becomes large, the weight of the sandwich becomes large, and it becomes difficult to handle the sandwich, which is dangerous.

[0005]

SUMMARY OF THE INVENTION The inventors of the present invention firmly bond base materials to each other even when manufacturing a molded article in which a plurality of skin materials are bonded to the surface of a thermoplastic resin base material. A manufacturing method that can be achieved and that does not require manual attachment / detachment of the sandwiched body has been studied, and a patent has already been applied (Japanese Patent Application No. 2).
001-283895). In the present invention, the entire sandwich is protruded from the mold cavity surface by the power, and the entire sandwich is housed in the mold cavity surface by the power or the self-weight, so that the multilayer molded body can be manufactured safely and efficiently.

The present invention has been made by paying attention to the above circumstances, and its object is a multilayer molded article which is excellent in safety and efficiency in spite of being further simplified. It is to provide a manufacturing die.

Another object of the present invention is to provide a mold for producing a multi-layered molded product, which is capable of maintaining safety and efficiency and is further excellent in terms of cost reduction and manufacturing trouble reduction, and a multi-layered molded product using the same. It is to provide a manufacturing method.

[0008]

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have made only a single crack (sandwiching piece) of a sandwiching body project and fit into a cavity surface. By forming a part for sandwiching the boundary part of the skin material by pairing with this sandwiching piece, the mold for manufacturing the multilayer molded body is further simplified while maintaining safety and efficiency. The present invention has been completed based on the finding that the manufacturing cost can be reduced and that the cost can be reduced, and that the use of this mold can avoid complicated operations, thereby reducing manufacturing troubles.

That is, the mold for producing a multilayer molded article according to the present invention is such that the molten thermoplastic resin is supplied to the back sides of the first and second skin materials which are adjacent to each other in the plane direction, and the skin material and the thermoplastic A pair of male and female molds for laminating a resin with each other to manufacture a multi-layer molded body, wherein the mold cavity surface of the mold located on the back side of the skin material of the male mold and the female mold is divided into first and second molds.
When it is divided into one side and the other side with the boundary portion of the skin material as a boundary, a sandwiching piece accommodating portion for inserting a sandwiching piece is formed on one side of the cavity surface. , The other side of the cavity surface and the sandwiching piece respectively have a skin contact portion for sandwiching a boundary portion between the first and second skin materials, and a boundary portion containing a molten resin. A resin inflow portion for fixing is formed, and in a state where the sandwiching piece is projected from the sandwiching piece accommodating portion into the cavity by the drive transmission mechanism, the skin member formed on the sandwiching piece and the cavity surface. With the contact portions separated, the boundary portion of the skin material can be inserted and released between the skin contact portions, and the sandwiching piece is fitted into the sandwiching piece housing portion by the drive transmission mechanism or the self-weight of the sandwiching piece. The gist is that both skin contact portions can approach each other to sandwich the boundary portion of the skin material.

It is preferable that the sandwiching piece linearly reciprocate obliquely with respect to the cavity surface at the accommodating position of the sandwiching piece.

Further, the method for producing a multilayer molded article according to the present invention is that the first and second skin materials which are adjacent to each other in the plane direction are arranged between the male and female dies of a pair of male and female dies. The first cavity formed on the cavity surface of the mold located on the back side of the skin material.
The molten thermoplastic resin is supplied from the gate to the back surface of the first skin material, and the molten thermoplastic resin is supplied from the second gate formed on the cavity surface to the back surface of the second skin material, A method of manufacturing a molded body by bonding these supplied resins and the skin material together, wherein one side and the other side of the cavity surface are defined with a boundary portion between the first and second skin materials as a boundary. When divided into, by making the sandwiching piece project from the sandwiching piece accommodating portion formed on one side, the skin contact portion formed on this sandwiching piece and the other side of the cavity surface are formed. After separating the formed skin contact portion, the first and second skin materials are supplied, and the sandwiching piece is fitted into the sandwiching piece accommodating portion by power or self-weight to bring both skin contacting portions closer to each other. As a result, the boundary portion between the first and second skin materials is sandwiched between both contact portions, and By feeding the molten thermoplastic resin to the resin inlet portion formed on the other side and the clamping piece I face, and has a gist in that to fix the boundary.

In the above-mentioned manufacturing method, it is desirable that the boundary portion between the first and second skin materials be joined in advance before being sandwiched. It is also preferable to perform press molding.

In this specification, the term "thermoplastic resin" is used to include a thermoplastic elastomer.
In addition, in the present specification, "plurality of skin materials adjacent to each other in the plane direction" is not limited to one in which a plurality of skin materials are joined so as to be adjacent to each other in the plane direction; It is also used in the sense of including a single skin material having. Therefore, "the first and second skin materials that are adjacent to each other in the plane direction" include not only two skin materials that are joined so as to be adjacent in the plane direction, but also two design surfaces that are adjacent to each other in the plane direction. Including one skin material having.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail with reference to the accompanying drawings. However, the present invention is not limited to the illustrated examples, and is appropriate within the scope of the above and the following points. It is also possible to implement by making changes to the above, and all of them are included in the technical scope of the present invention. For example, in the following, a female mold is used as the mold located on the front side of the skin material, and a male mold is used as the mold located on the back side of the skin material. A male mold may be used as the metal mold located at, and a female mold may be used as the metal mold located at the back side of the skin material.

1 and 2 are schematic sectional views showing an example of the mold of the present invention, FIG. 3 is a partially enlarged sectional view of the mold, and FIG. 4 is a sectional view taken along the line AA 'of FIG. 5 is a sectional view taken along line BB ′ of FIG.

The mold 10a shown in FIGS. 1 and 2 is composed of a male mold 14 and a female mold 15 which are paired with each other to mold the thermoplastic resin. When the cavity surface of the male mold 14 is divided into one side X and the other side Y with the boundary portion 3 of the first and second skin materials 1 and 2 inserted into the mold 10a as a boundary, On one side X, a sandwiching piece accommodating portion (accommodating recess) 16 for inserting the sandwiching piece 31a is provided.
Is formed so as to contact with. 3 to 5
As shown in FIG. 5, the sandwiching piece 31a and the other side Y of the cavity surface accommodate the skin contact portions 32 and 33 for sandwiching the boundary portion 3 from the back side and the molten resin, respectively. Resin inflow portions 34 and 35 for fixing the boundary portion 3 are formed.

In this example, the sandwiching piece 31a has an inclined side wall 36a which is inclined outward (to a direction in which the skin contact portions 32, 33 are separated from each other), which will be described later. In addition, the sandwiching piece 31a can be linearly reciprocated in an oblique direction along this inclination, and both skin contact portions 32, 33 can be moved.
Can be separated or brought into contact with each other.

That is, as shown in FIGS. 1 and 2, the sandwiching piece 31a accommodated in the sandwiching piece accommodating portion 16 is connected to a shaft (drive transmission mechanism) 41a inclined in the same direction as the inclined side wall 36a. And cylinder (not shown)
Can be reciprocated by.

When the force of the cylinder is transmitted to the sandwiching piece 31a via the shaft 41a using the mold 10a, since the side wall 36a of the sandwiching piece 31a is inclined,
The sandwiching piece 31a can be projected obliquely with respect to the cavity surface (see FIG. 2). Therefore, the skin contact portion 3
2, 33 can be separated from each other, and the corresponding contact portions 32, 33
A boundary portion 3 between the skin materials 1 and 2 can be inserted between them.

On the other hand, when the shaft 41a is moved backward, the sandwiching piece 31a can be fitted into the accommodating portion 16 and the skin abutting portions 32, 33 can be moved closer to each other by the operation opposite to the case of the forward movement (FIG. 1). Therefore, the boundary portion 3 between the skin materials 1 and 2 can be sandwiched.

In the mold 10a, on the cavity surface of the male mold 14, a first gate 11 for supplying the molten thermoplastic resin to the back surface of the first skin material 1, and a second skin material. A second gate 12 for supplying a molten thermoplastic resin is formed on the back surface of the second gate 12. Although each of the first gate 11 and the second gate 12 is formed in plural, in the illustrated example, only one of each is illustrated for simplicity.

By using the mold 10a as described above, a molded body can be manufactured as described below.
6 to 9 are schematic cross-sectional views for explaining a method for manufacturing a molded body using the mold 10a.

That is, as shown in FIG. 6, the force of a cylinder (not shown) causes the sandwiching piece 31a to project from the cavity surface of the mold, whereby the skin contact portion 32 formed on the sandwiching piece 31a. And the skin contact portion 33 formed on the other side Y of the cavity surface are separated. Then, between the abutting portions 32, 33, the first and second skin materials 1,
Feed and insert the two ends. These end portions become the boundary portion 3 between the first and second skin materials 1 and 2 after the production of the molded body. In addition, in this example, the end portions (edges) of the skin materials 1 and 2 are joined in advance before the insertion. Further, in this example, a pin (not shown) as a positioning tool is used to ensure the insertion of the end portion (that is, the boundary portion).

After inserting the end portion (boundary portion 3), as shown in FIG. 7, the sandwiching piece 3 is formed by the force of a cylinder (not shown).
The end portion (boundary portion 3) is sandwiched by inserting 1a into the housing portion 16 and bringing both skin contact portions 32 and 33 close to each other. By sandwiching the boundary portion 3, the first and second skin materials 1 and 2 can be adjacent to each other in the plane direction, and the back surfaces of the skin materials 1 and 2 are set in the mold 10a so that they face the male mold 14. it can. After setting, the first gate 1 is provided on the back surface of the first skin material 1.
1, the molten thermoplastic resin 21 is supplied, and the molten thermoplastic resin 2 is supplied from the second gate 12 to the back surface of the second skin material 2.
Supply 2.

After the thermoplastic resin is supplied, as shown in FIG. 8, the female die 15 is moved toward the male die 14 (that is,
Mold clamping is started), and molten thermoplastic resins 21 and 22 are filled in the mold cavity while pressing the resin.
Then, by cooling and solidifying the resin, the skin materials 1, 2
It is possible to manufacture a multilayer molded body in which and the thermoplastic resins 21 and 22 are integrally bonded to each other. When the molten resins 21 and 22 are filled, the resins 21 and 22 are
It is also fed to the resin inflow portions 34 and 35 (see FIGS. 3 to 4) formed on the sandwiching piece 31a and the cavity surface Y. Therefore, the boundary portion 3 is also fixed by cooling and solidifying the resin.

The molded body can be taken out as shown in FIG. That is, the mold 10a is opened, and the clamping piece 31a is pressed by the force of the cylinder (not shown).
Project from the cavity surface of the mold,
By separating 2 and 33, the boundary portion 3 between the skin materials 1 and 2 can be released and the molded body can be taken out.

By using the mold as described above, the protrusion and fitting of the sandwiching piece can be automated without the need for manual operation, so that the multilayer molded body can be manufactured safely and efficiently. Moreover, since not one pair of sandwiching pieces is used but only one sandwiching piece is used, the mold can be simplified and manufacturing troubles can be reduced.

In the present invention, as will be described later,
Resin 2 supplied from the first and second gates 11 and 12
As 1 and 22, a molten thermoplastic resin (foaming resin) containing a foaming agent can be used. When a foamable resin is used, the obtained molded product may be foamed after being taken out from the mold, but it is preferable to foam the molded product in the mold.

FIG. 10 is a schematic sectional view for explaining the case of foaming a resin. In this example, the mold 10a is used, and after the filling of the foamable resins 21 and 22 into the mold cavity by the molding is completed [see FIG. 8], the male mold 14 or the female mold 15 is clamped. By moving the mold cavity in the opposite direction, the mold cavity is expanded and the filling resin (base resin) is foamed (FIG. 10).

When the molten foaming resins 21 and 22 are filled in the mold cavity, the cavity clearance formed by the male mold 14 and the female mold 15 is controlled at the time of filling to prevent the escape of foaming gas. Then, it is desirable to prevent insufficient foaming during the foaming operation after completion of filling. That is, the cavity clearance is usually 1
Although it is appropriately set according to the molding conditions such as the two types and the resin temperature, it is desirable to prevent the escape of the foaming gas by paying attention to the small cavity clearance when filling the foamable resin.

Foaming resin 21, 2 into the mold cavity
After the filling of 2 is completed, it is preferable to cool the resin surface layer to form a skin layer before expanding the mold cavity. If the skin layer is too thick, a sufficient expansion ratio cannot be obtained, so it is desirable to control the thickness so that a sufficient expansion ratio is obtained. The thickness of the skin layer can be controlled, for example, by adjusting the formation time of the skin layer in consideration of the thickness of the molded product, the mold temperature and the like.

In expanding the mold cavity, the extent of expansion (expansion allowance) is the thickness of the product to be manufactured (foaming ratio).
Can be determined as appropriate. When expanding and foaming the mold cavity, it is desirable that the sandwiching piece 30a be left fitted in the sandwiching piece accommodating portion 16.

The foaming method is not limited to the case where the mold 10a is used, but can be adopted when various other molds including the mold described later are used.

Further, by projecting the sandwiching piece into the cavity, the skin abutting portion can be separated and the boundary portion can be inserted and released, and by inserting the sandwiching piece into the accommodating portion, the skin abutting portion can be approached. As long as the boundary portion can be sandwiched by the above, the sandwiching piece does not necessarily need to be diagonally reciprocated linearly, and may be moved in a substantially vertical direction. For example, a shaft that is substantially perpendicular to the cavity surface is used, the shaft and the sandwiching piece are connected by a suitable connecting means, and after the sandwiching piece is projected substantially vertically by the shaft, the connecting means is used. Example of moving or tilting the sandwiching piece in the opening direction (Example A),
An example (Example B) in which the sandwiching piece is moved along an appropriate guide to be projected substantially vertically and then moved or tilted in the opening direction can be given.

11 to 12 are schematic sectional views of the mold 10b of the first example of the above-mentioned example A. In this mold 10b, a sandwiching piece 31b is rotatably connected to a shaft 41b that is substantially orthogonal to the cavity surface via a erection rod 42b (communication means). Of the erection rod 42b, the shaft 41b side. The end of the shaft 41 is rotatable and the shaft 41
It can be slid along the groove 43 formed in b (see FIG. 11). Further, the rotating portion of the erection rod is provided with torque generating means (torsion spring or the like; not shown) for generating a force in the rotating direction. The other structure of the mold 10b is the same as that of the mold 10a.

When such a mold 10b is used, by moving (advancing) the shaft 41b in the projecting direction, the sandwiching piece 31b can also be projected in the substantially vertical direction. Then, when the sandwiching piece is projected until the side wall 36b of the sandwiching piece 31b is not in contact with the inner wall of the sandwiching piece accommodating portion 16b, the sandwiching piece 31b is opened by the torque generating means as shown in FIG. Can be moved in any direction. Therefore, the two skin contact portions 32 and 33 can be largely separated from each other, and the boundary portion (end portion) between the skin materials 1 and 2 can be inserted and released.

FIG. 13 is a schematic sectional view of a mold 10c of the second example of the above-mentioned example A. In this example, the sandwiching piece 31c is rotatably attached to the shaft 41c that is substantially orthogonal to the cavity surface via the shaft attachment portion 42c (communication means). Then, the side wall 36c of the sandwiching piece 31c is accommodated in the housing portion 1
When the sandwiching piece 31c is projected until it does not come into contact with the inner wall of 6c, the sandwiching piece 31c is tilted toward the opening direction (outward) by the torque generating means (not shown) provided in the shaft mounting portion. Both skin contact parts 32, 33
Can be widely separated.

Even if such a mold 10c is used, when the sandwiching piece 31c is projected, as is the case with the mold 10b,
The boundary portion (end portion) of the skin materials 1 and 2 can be inserted and released, and the boundary portion 3 can be clamped when the clamping piece 31c is fitted in the housing portion 16.

FIG. 14 is a schematic sectional view of a mold 10d of the third example of the above-mentioned example A. Also in this example, the elastic portion (connecting means) is provided on the shaft 41d that is substantially orthogonal to the cavity surface.
The sandwiching piece 31d is connected via 42d. The elastic portion 42d is bent outward (toward the opening direction of the sandwiching piece). Therefore, the sandwiching piece 31d
When the sandwiching piece 31d is projected until the side wall 36d of the shell does not contact the inner wall of the sandwiching piece housing portion 16d, the elastic portion 42
By the action of d, the sandwiching piece 31d can be tilted in the opening direction (outward), and the boundary portion 3 (end portion) of the skin materials 1 and 2 can be inserted and released. Further, when the holding piece 31d is fitted in the housing portion 16, the boundary portion 3 can be held.

In Example A, the means for moving or tilting the sandwiching piece in the opening direction is not particularly limited, and for example, a cylinder or the like may be used, and this moving or tilting means may be provided outside the mold. Good. As an example of providing the moving or tilting means outside the mold, a sandwiching piece extending to the outside of the die is used, and the sandwiching piece is opened in the opening direction by pressing the portion extending to the outside with a cylinder or a spring. Examples of moving or tilting can be given.

15 to 16 show a mold 10e belonging to Example B.
FIG. In this example, the sandwiching piece accommodating portion 1
A guide 50 that is substantially orthogonal to the cavity surface is attached to 6e. The guide 50 is inclined outward (toward the opening direction of the sandwiching piece) on the cavity surface side and the back side. In the sandwiching piece 31e used in this example, a guide insertion portion 51 for moving the sandwiching piece along the guide 50 extends from the sandwiching piece 31e. Further, the sandwiching piece 31e is supported by a shaft 41e, and this shaft 41e is connected to a cylinder (not shown) so that it can be moved back and forth.

By using such a mold 10e, the sandwiching piece can be projected substantially vertically by the shaft 41e. When the sandwiching piece 31e is further projected, as shown in FIG.
As shown in FIG. 6, since the guide 50 is inclined outward on the cavity surface side, the sandwiching piece 31e can be moved in the opening direction along the guide 50, and the skin materials 1, 2 The boundary (end) can be inserted and released. Further, when the sandwiching piece 31e is fitted into the housing portion 16e, the boundary portion 3 between the skin materials 1 and 2 can be sandwiched.

Any of the mechanisms used in the example of moving the sandwiching piece in the substantially vertical direction can be used even in the case of moving it diagonally.

In the present invention, it is desirable that the sandwiching piece be linearly moved in an obliquely reciprocating manner. When the reciprocating linear motion is performed, since the motion mechanism is simple, the risk of damaging the motion body (the drive transmission mechanism such as the shaft) is low and the maintenance is easy. Therefore, a molded body can be manufactured stably over a long period of time. Furthermore, since the boundary portion of the skin material can be clamped only when the sandwiching piece is completely accommodated, the possibility that the boundary portion is twisted is extremely low.

Further, in the present invention, a molded body may be manufactured by controlling the flow of resin by using a resin stopper plate. FIG. 17-
FIG. 19 is a schematic cross-sectional view showing an example of the case where a resin stop plate is used. In this example, a mold 10f having a resin stop plate installed on the mold 10a used in FIGS. 1 to 9 is shown. There is. That is, as shown in FIG. 17, this mold 10f is
A first resin stop plate 61 and a second resin stop plate 62 are embedded in the male mold 14 on both sides of a position corresponding to the boundary 3 so as to project substantially along the boundary 3. Similar to the sandwiching piece 31a, the resin stopper plates 61 and 62 can be protruded from the cavity surface by a cylinder (not shown) and can be housed in the male mold 14.

Then, as shown in FIG. 17, the skin materials 1, 2
Is sandwiched between the skin contact portions 32 and 33, and both resin stopper plates 61,
In a state in which 62 is projected into the mold cavity, the molten thermoplastic resin 2 is discharged from the first gate 11 and the second gate 12.
1 and 22 are supplied. After the resin is supplied, as shown in FIG. 18, the female mold 15 is moved in the mold clamping direction, and the molten thermoplastic resin is filled on the back side of the skin material while pressing the resin. When the molten resin substantially fills the outside of the resin stopper plates 61 and 62 (that is, the outside when the side where the boundary 3 is present is the inside), the accommodation of the resin stopper plates 61 and 62 is started, and The press is continued to manufacture a molded body (see FIG. 19). When the molded body is manufactured by such a method, the resin stopper plates 61 and 62 are projected from the cavity surface at the stage of filling the molten thermoplastic resin, and the resin stopper plates 61 and 62 are projected to the female mold 15 through the skin materials 1 and 2. Therefore, even if the flow of the resin is biased, it is possible to prevent either one of the molten resins 21 and 22 from reaching the boundary portion first, and it is possible to highly prevent the displacement of the boundary portion 3.

Further, in the present invention, it is desirable to provide a continuous protrusion (wood grain arrow) along the boundary at a position corresponding to the boundary 3 between the skin materials 1 and 2 in the female die 15. FIG. 20 is a schematic cross-sectional view of a mold 10g in which the mold 10a is provided with a protrusion (wood grain arrow). Such a mold 10
When g is used to manufacture a molded body as in the case of the mold 10a, the protrusion 70 can highly prevent the displacement of the boundary portion 3. The protrusion 70 may be capable of protruding from the female mold 15.

The drive transmission mechanism is not limited to the shaft, and various means can be used. For example, a plate-shaped body may be used instead of a rod-shaped body such as a shaft. Further, along with the advancing direction of the sandwiching piece, two kinds of gears (pinions) of large and small that mesh with each other are arranged alternately and continuously, and a rack that meshes with the larger pinion is formed on the sandwiching piece, which is large. The sandwiching piece may be moved back and forth by rotating the other pinion. Even when the pinion and the rack are used, as in the case of using the shaft, the sandwiching piece may be linearly reciprocated in an oblique direction or may be moved in a substantially vertical direction.

Even when the drive transmission mechanism is used, when the sandwiching piece is accommodated, the self-weight of the sandwiching piece may be used instead of using the drive transmission mechanism. Further, it is not necessary to connect the drive transmission mechanism (rod-shaped body, plate-shaped body, etc.) and the sandwiching piece, and the sandwiching piece may be supported by the drive transmission mechanism.

Further, the power for operating the drive transmission mechanism is not particularly limited, and in addition to linear motion power such as the cylinder (air cylinder, hydraulic cylinder, etc.), rotary motion power such as a motor. May be Even when the rotary motion type power is used, the rod-shaped body or the plate-shaped body is linearly reciprocated by a conventional mechanism (a slider-crank mechanism, a mechanism using a cylindrical cam, etc.) for converting the rotary motion into the linear motion. Can be exercised.

The sandwiching piece used in the present invention is not particularly limited as long as it has a shape along the boundary part (boundary line), and may be continuous over the entire boundary line, or divided into a plurality of parts. It may have been done.

The distance between the skin contact portion 32 formed on the sandwiching piece and the skin contact portion 33 formed on the cavity surface Y is
It is set so that the boundary portion 3 between the skin materials 1 and 2 can be appropriately clamped. That is, when the sandwiching piece is housed in the housing part, the distance between the two skin contact parts 32, 33 is equal to the skin material 1,
2 or less, and is appropriately set according to the type and properties of the skin material used from the viewpoint of whether or not the boundary portion 3 can be tightly clamped without moving when supplying molten resin or clamping the mold. It is possible to set, for example, about 0.1 to 0.9 times, preferably about 0.1 to 0.5 times the total thickness of the two skin materials.

When performing mold clamping, either the male mold 14 or the female mold 15 may be moved, or both may be moved. Further, in each of the illustrated examples, an example is shown in which a molded body is manufactured by press molding in which the mold is clamped and the resin is pressed after the completion of the resin supply, but the mold clamping is not necessarily performed after the completion of the resin supply. May be performed while supplying. When the mold is clamped after the supply of the resin is completed, it is desirable to start the mold clamp immediately after the completion of the supply. In each of the illustrated examples, the mold clamping is performed in the vertical direction, but the mold clamping may be performed in a direction other than the vertical direction (for example, the horizontal direction).

Further, the molding method is not limited to press molding,
It may be injection molding or a combination of press molding and injection molding. For example, when a molded body is manufactured by injection molding, the male mold 14 accommodates the sandwiching piece and sandwiches the skin materials 1 and 2, and then the mold clamping is completed, and the molten thermoplastic resin is injected from the gates 11 and 12. The molded body may be manufactured by supplying When the press molding and the injection molding are combined, the same operation as in the press molding may be performed except that the initial resin supply amount is small, and the insufficient resin may be injected and supplied at an appropriate stage.

The preferred molding method is press molding. In the case of injection molding, since the molten resin is injected and supplied after the mold clamping is completed, the skin materials 1 and 2 may come into contact with the molten resin under high pressure and the skin materials 1 and 2 may be damaged. In press molding, resin is supplied with the mold open,
There is less risk of damaging the skin materials 1 and 2 due to the supply pressure of the resin.

In the present invention, the skin materials 1 and 2 may be shaped (preliminarily shaped) according to the shape of the molded body (that is, the shape of the female die 15) before sandwiching.

In the illustrated example, the boundary portion 3 between the skin materials 1 and 2 is preliminarily joined before being sandwiched, but the joining means is not particularly limited, and, for example, a chemical joining method (adhesive or In addition to heat-sealing), a method using a jig (sewn with thread; fixed with needle, pin, stapler, etc.) and the like can be mentioned. Further, in the illustrated example, the skin material is fixed to the sandwiching piece by using the pin as the positioning tool, but the positioning tool is not limited to the pin, and for example, locking means such as a hook or tightening means such as a band. Various means such as can be used.

In the present invention, it is not always necessary to join the boundary portion in advance prior to the sandwiching. A positioning tool may be used to attach the skin material 2 to the cavity surface Y if the boundaries are not joined in advance.

Further, in the present invention, the positioning tool is not always necessary.

The skin material used in the present invention is not particularly limited in the number of skin materials as long as the design surface has a boundary portion.
The two skin materials (first skin material 1 and second skin material 2)
Instead of this, a single skin material having a first skin material (design surface) and a second skin material (design surface) may be used. When one sheet of skin material is used, the boundary portion of the skin material (design surface) is bent and sandwiched from the back side. When two sheets of skin material are used, a boundary portion is always formed, so the first skin material and the second skin material may be the same or different.

The number of skin materials (design surface) is not limited to two, and may be three or more. For example, when a third skin material (design surface) is formed in addition to the first skin material (design surface) 1 and the second skin material (design surface) 2, the third skin material (design surface) 3
The boundary with the skin material (design surface) may be sandwiched in the same manner as above.

The number of gates for supplying resin to the back side of each skin material (design surface) may be at least one, and a plurality of gates may be formed according to the area of the skin material (design surface). The amount and timing of the resin supplied from these gates are appropriately determined according to the size and shape of the molded product.

In the illustrated example, the thermoplastic resin is introduced into the mold through the common resin introduction passage, and the passage is branched in the mold to generate heat from the first gate 11 and the second gate 12. Although the plastic resin is supplied, separate resin introducing passages (a resin introducing passage for the first gate 11 and a resin introducing passage for the second gate 12) may be provided.

Examples of the skin material that can be used in the present invention include cloths (for example, woven or knitted fabrics such as moquette and tricot; non-woven fabric), synthetic resin sheets or films, metal foils (metal foils) and the like.

As the fibers constituting the non-woven fabric, natural fibers (cotton, wool, silk, linen, etc.), synthetic fibers (polyamide fibers such as nylon, polyester fibers) and the like can be used. These fibers can be used alone or in combination of two or more, and may be spun (blended, etc.) if necessary. As the non-woven fabric, a non-woven fabric produced using the above-mentioned fibers by a conventional method (needle punch method, thermal bond method, spun bond method, melt blow method, spun lace method, etc.) can be used.

The synthetic resin sheet or film may be, for example, a thermoplastic resin (eg polypropylene,
A sheet or film of polyolefin type thermoplastic resin such as polyethylene) or a sheet or film of polyolefin type thermoplastic elastomer can be used. The polyolefin-based thermoplastic resin (or elastomer) is excellent in heat fusion property to the base material.

The skin material may be laminated with a backing layer (foaming layer, reinforcing layer, heat-resistant layer, etc.), if necessary. As the foam layer, polyolefin foam (foam such as polypropylene or polyethylene), polyvinyl halide foam (such as polyvinyl chloride foam), polyurethane foam (such as soft or semi-rigid polyurethane foam) can be used. .

Examples of the reinforcing layer include non-woven fabric, synthetic resin sheet or film. As the non-woven fabric and the synthetic resin sheet or film, the same ones as those exemplified for the skin material can be used.

The backing layer may be used alone or in combination of two or more. Further, the backing layer is preferably one that can be thermally laminated to the skin material by either heat-sealing the skin material or heat-sealing the backing layer.

The thermoplastic resin constituting the base material of the molded article is not particularly limited as long as compression molding or injection molding is possible. For example, a polyolefin resin (polypropylene, polyethylene, etc.), a styrene resin (polystyrene, Styrene-butadiene block copolymer, acrylonitrile-styrene-butadiene block copolymer, etc.), polyamide resin (nylon, etc.), halogen-containing resin (polyvinyl chloride, etc.), polycarbonate resin, (meth) acrylic acid ester alone Alternatively, a copolymer (acrylic resin or the like) can be used. The thermoplastic resin may be a thermoplastic elastomer, and for example, an olefinic thermoplastic elastomer [eg, ethylene-propylene copolymer (EPM), ethylene-propylene-diene copolymer (EPDM)] can be used. .

The above-mentioned thermoplastic resins (and thermoplastic elastomers) can be used alone or in combination of two or more, and may be used, for example, as a polymer alloy.

Further, the thermoplastic resin (and the thermoplastic elastomer) contains various additive components such as fillers (inorganic fillers such as glass fibers; organic fillers), pigments, lubricants, antistatic agents, stabilizers and the like. You may have.

The thermoplastic resin (and the thermoplastic elastomer) may contain a foaming agent. By foaming the resin with this foaming agent, it is possible to obtain a molded body formed of a foaming base material. As the foaming agent, a known chemical foaming agent (such as a decomposable foaming agent) used when foaming a thermoplastic resin can be used. For example, an inorganic type such as sodium bicarbonate, ammonium bicarbonate, or ammonium carbonate can be used. Blowing agent; Nitroso compounds such as N, N'-dinitrosopentamethylenetetramine; Azo compounds such as azodicarbonamide and azobisisobutyronitrile;
Examples include sulfonyl hydrazides such as benzene sulfonyl hydrazide, toluene sulfonyl hydrazide, and diphenyl sulfone-3,3′-disulfonyl hydrazide; p-toluene sulfonyl semicarbazide and the like. Furthermore, it is preferable to add salicylic acid, urea, and a foaming aid containing these, if necessary. The foaming agent can be appropriately selected in consideration of the melting temperature of the thermoplastic resin used and the required expansion ratio. Further, the addition amount can be appropriately set in consideration of the required strength and required density of the molded product, but in general, it is 0.1 to 5 with respect to 100 parts by mass of the resin.
It is about part by mass. When performing the above-mentioned foaming operation, a volatile liquid foaming agent, a gas foaming agent, etc. may be directly pressed into the molten resin in the mold, in addition to the method of incorporating the chemical foaming agent into the thermoplastic resin. . Carbon dioxide, nitrogen and the like can be used as the volatile liquid foaming agent and the gas foaming agent.

According to the present invention, a multilayer molded article having a plurality of design surfaces can be efficiently and safely produced.
This is advantageous for manufacturing interior parts of automobiles (for example, door trims, instrument panels, etc.) and interior / exterior parts of home appliances.

[0075]

According to the present invention, only the split pieces (sandwich pieces) of the sandwich body are projected and fitted, and the cavity surface is paired with this sandwich piece to form the boundary portion of the skin material. Since the portion for sandwiching is formed, the mold for producing the multilayer molded body can be further simplified and the cost can be reduced while maintaining safety and efficiency. Moreover, if this mold is used, complicated operations can be avoided, and manufacturing troubles can be reduced.

[Brief description of drawings]

FIG. 1 is a first diagram of a series of schematic cross-sectional views showing an example of a mold of the present invention.

FIG. 2 is a second view of a series of schematic cross-sectional views showing an example of the mold of the present invention.

FIG. 3 is a partially enlarged sectional view of the mold of FIGS.

FIG. 4 is a sectional view taken along the line A-A ′ of FIG.

5 is a sectional view taken along the line B-B ′ of FIG.

FIG. 6 is a first drawing of a series of schematic cross-sectional views for explaining an example of a method for manufacturing a molded body using the mold of FIGS.

FIG. 7 is a second diagram out of a series of schematic cross-sectional views for explaining an example of a method for manufacturing a molded body using the mold of FIGS.

FIG. 8 is a third diagram out of a series of schematic cross-sectional views for explaining an example of a method for manufacturing a molded body using the mold of FIGS.

FIG. 9 is a fourth diagram out of a series of schematic cross-sectional views for explaining one example of the method for manufacturing a molded body using the mold of FIGS.

FIG. 10 is a schematic cross-sectional view for explaining another example of the manufacturing method of the present invention.

FIG. 11 is a first diagram of a series of schematic cross-sectional views showing another example of the mold of the present invention.

FIG. 12 is a second view of a series of schematic cross-sectional views showing another example of the mold of the present invention.

FIG. 13 is a schematic sectional view showing still another example of the mold of the present invention.

FIG. 14 is a schematic cross-sectional view showing another example of the mold of the present invention.

FIG. 15 is a first view of a series of schematic cross-sectional views showing still another example of the mold of the present invention.

FIG. 16 is a second view of a series of schematic cross-sectional views showing still another example of the mold of the present invention.

FIG. 17 is a first diagram of a series of schematic cross-sectional views showing another example of the mold of the present invention.

FIG. 18 is a second view of a series of schematic cross-sectional views showing another example of the mold of the present invention.

FIG. 19 is a third view of a series of schematic cross-sectional views showing another example of the mold of the present invention.

FIG. 20 is a schematic sectional view showing still another example of the mold of the present invention.

FIG. 21 is a schematic cross-sectional view for explaining a conventional method for manufacturing a molded body.

[Explanation of symbols]

1, 2 ... skin material 3 ... Border 10a-10g ... Mold 11,12 ... Gate 14 ... Mold located on the back side of the skin material 15 ... Mold located on the front side of the skin material 16 ... sandwiching piece accommodating portion 21, 22 ... Molten thermoplastic resin 31a to 31g ... sandwiching piece 32, 33 ... Skin contact part 34, 35 ... Resin inflow part 41a-41e ... Drive transmission mechanism Y ... The other side of the cavity surface

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4F202 AD08 AD20 AD35 CA09 CA11                       CA30 CB13 CQ05                 4F206 AD08 AD20 AD35 AG03 JA03                       JA07 JB13 JB20 JF05 JF35                       JL02 JN25 JQ06 JQ81

Claims (5)

[Claims] 1. A first and a second which are adjacent to each other in a plane direction.
A pair of male and female molds for supplying a molten thermoplastic resin to the back side of the skin material and manufacturing a multilayer molded article by laminating the skin material and the thermoplastic resin together. When the cavity surface of the mold located on the back side of the skin material is divided into one side and the other side with the boundary portion of the first and second skin materials as a boundary, one side of the cavity surface A sandwiching piece accommodating portion for inserting the sandwiching piece is formed on the other side of the cavity surface and the sandwiching piece, respectively.
A skin contact portion for sandwiching a boundary portion between the first and second skin materials, and a resin inflow portion for accommodating a molten resin and fixing the boundary portion are formed. With the sandwiching piece projecting from the sandwiching piece accommodating portion into the cavity, the skin abutting portions formed on the sandwiching piece and the cavity surface are separated from each other, and the skin material is interposed between the skin abutting portions. The boundary part can be inserted and released, and both skin contact parts approach and the boundary part of the skin material is sandwiched by the drive transmission mechanism or the self-weight of the sandwiching piece when the sandwiching piece is fitted in the sandwiching piece housing part. A mold for manufacturing multi-layer molded products that can be manufactured. 2. The mold according to claim 1, wherein the sandwiching piece linearly reciprocates obliquely with respect to the cavity surface at the accommodating position of the sandwiching piece. 3. Between a male mold and a female mold of a pair of male and female molds,
The first and second skin materials that are adjacent to each other in the plane direction are arranged, and the molten state is formed from the first gate formed on the cavity surface of the mold located on the back side of the skin material to the back surface of the first skin material. A thermoplastic resin is supplied, and a molten thermoplastic resin is supplied from the second gate formed on the cavity surface to the back surface of the second skin material, and the supplied resin and the skin material are bonded together to form A method of manufacturing a body, wherein the cavity surface is formed on one side when divided into one side and the other side with a boundary portion between the first and second skin materials as a boundary. After the sandwiching piece is projected from the sandwiching piece accommodating portion, the skin contacting portion formed on the sandwiching piece and the skin contacting portion formed on the other side of the cavity surface are separated from each other. , Supplying the first and second skin materials,
By inserting the sandwiching piece into the sandwiching piece accommodating portion by power or its own weight to bring the two skin contacting portions closer to each other, the contacting portion sandwiches the boundary portion between the first and second skin materials, A method for producing a multilayer molded article, characterized in that the boundary portion is fixed by feeding a molten thermoplastic resin into the resin inflow portion formed on the other side of the cavity surface and the sandwiching piece. 4. The manufacturing method according to claim 3, wherein the edges of the first and second skin materials are preliminarily joined prior to sandwiching the boundary portion between the first and second skin materials. 5. The method according to claim 3 or 4, wherein the molten thermoplastic resin supplied to the back side of the first and second skin materials is pressed by a male mold and a female mold to fill the resin into the mold cavity. The manufacturing method described.