JP2932930B2 - Method for molding resin products and molding apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a resin product, such as an instrument panel for an automobile, in which a sheet material is partially heat-sealed to the surface of a substrate body, and a mold for molding the resin product. It concerns the device.

[0002]

2. Description of the Related Art In general, an instrument panel (hereinafter referred to as "instrument panel") comprises a base made of a hard resin and an elastic sheet material attached to the surface thereof.
Due to its structure, the instrument panel is a "full pad type" in which an elastic sheet material is provided on the entire surface, a "half pad type" in which a part of the base material is exposed, and a "padless type" consisting only of the base material ] Are roughly divided into three types.

For example, as shown in FIG. 8, a base material 52 of a "half pad type" instrument panel 51, which is often used in a public car, is required to have a predetermined rigidity and formability, so that ABS (acrylonitrile) is used. -Butadiene-styrene), PP (polypropylene) and the like. The elastic sheet material 53 is made of, for example, a cushion layer 54 made of a flexible polyurethane foam,
A skin layer 55 made of (polyvinyl chloride) is provided.

The instrument panel 51 is formed, for example, as follows. That is, the elastic sheet material 53 is previously formed into a predetermined shape by known vacuum forming or the like. Next, FIG.
As shown in (1), the elastic sheet material 53 is set at a predetermined position in a mold device 56 for molding the base material 52.
This mold device 56 has a fixed mold 57 and a movable mold 58,
These two dies 57 and 58 form a cavity 59 for forming the base material 52. Then, the plasticized resin material is injected and filled into the cavity 59 from the gate 60. Then, the base material 52 is formed of the resin material, and the elastic sheet material 53 is thermally fused to the surface thereof. After that, the excess resin corresponding to the gate 60 is removed, and the instrument panel 51 described above is obtained.

[0005]

However, in the above technique, the resin material is injected from the nozzle (hot runner) of the injection molding machine into the cavity 59 through the gate 60. At this time, the resin material may reach the cavity 59 directly. In this case, the resin material directly hits the cushion layer 54 of the elastic sheet material 53 and the like, and the pressure and heat of the resin material may be directly and locally applied. As a result, the cushion layer 54 and the like may be damaged, and as a result, the appearance quality may be deteriorated.

In order to simplify the structure of the mold device 56, the gate 60 is provided in parallel with the moving direction of the movable mold 58,
That is, it is formed obliquely to the length direction of the cavity 59. The internal space of the gate 60 is formed so as to form a part of a truncated cone whose diameter increases toward the cavity 59 side. For this reason, in the above technique, the gate 60
The opening portion of the portion opening to the cavity 59 of FIG.
As shown in FIG. 5, the opening area becomes relatively large while having a substantially elliptical shape. Therefore,
The root portion of the surplus portion corresponding to the gate 60, which protrudes from the base material 52 immediately after molding, was thick (close to a circle) and had a very large cross-sectional area. Therefore, there is a large difference in the time required for the cooling and solidification between the portion corresponding to the gate 60 and the portion other than the gate 60, and there is a possibility that so-called “sink” may occur on the surface side of the base material 52. As a result, the appearance quality may be significantly reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a resin product having a base material body and a sheet material heat-sealed on the surface of the base material. It is an object of the present invention to provide a method of molding a resin product and a molding apparatus for molding the resin product, which can suppress the occurrence of cracks and damage to a sheet material, thereby reliably preventing the appearance quality from being deteriorated.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a base material body made of a resin material, and a sheet material thermally fused to a part of the surface thereof. A method for forming a resin material, comprising: forming the sheet material by a vacuum forming method to have a predetermined shape; and a partly set surface on which the sheet material is set, wherein the base material A first mold provided with a first molding surface for forming a part of the main body, and a first mold which is disposed so as to be relatively close to and separated from the first mold, and is provided with a remaining part of the base body. Preparing a mold apparatus including a second mold having a second molding surface for forming a portion, and substantially abutting a surface of the sheet material with a set surface of the first mold. In this state, the sheet material is placed in a cavity defined by the first molding surface and the second molding surface. Setting, injecting the plasticized resin material into the cavity from at least one gate provided in the second mold, and filling the cavity; Removing the fused base material body from the mold apparatus, and forming the gate in a flat shape, and, by using a resin material existing in the gate, from the base material body to the back surface side. The gist of the present invention is to form the ribs projecting from the body integrally.

Further, in the invention according to claim 2,
A mold apparatus for molding a resin product including a base material body made of a thermoplastic resin and a sheet material that is thermally fused to a part of the base body surface, A first forming surface for forming a part of the base material body, the first forming surface having a setting surface on which the sheet material is set;
And a second mold, which is disposed so as to be relatively movable toward and away from the first mold, and forms a cavity for forming the base material body by alignment with the first molding surface. A second mold having a molding surface, and having a gate for injecting a plasticized resin material for forming the base material main body into the cavity; and The gist is that the gate is formed in a flat shape so that a rib protruding from the base material body toward the back surface is integrally formed of the existing resin material.

[0010]

According to the first aspect of the present invention, first, a sheet material is formed into a predetermined shape by a vacuum forming method. A first mold having a first molding surface; and a second mold having a second molding surface, which is disposed so as to be relatively movable toward and away from the first mold. Is prepared. Further, the sheet material is set in a cavity formed by the first molding surface and the second molding surface while the surface of the sheet material is substantially in contact with the setting surface of the first mold.

Then, the plasticized resin material is used as the second resin.
Is injected and filled into the cavity from at least one gate provided in the mold. Thereafter, the base material body having the sheet material thermally fused to a part of the surface is taken out of the mold apparatus. Through the above series of steps, a resin product comprising a base material body made of a resin material and a sheet material thermally fused to a part of its surface is formed.

In the present invention, the injected resin material is once diffused in the gate and then filled in the cavity. At this time, the injected resin material is unlikely to directly hit the sheet material, so that the pressure and heat of the resin material are prevented from being directly and locally applied. Therefore, the sheet material is prevented from being damaged by the pressure and heat.

Further, the gate is formed in a flat shape, and a rib protruding from the base material body to the back side is integrally formed by the resin material existing in the gate. For this reason, the root portion of the surplus portion corresponding to the gate is formed in a flat shape, so that there is no large difference in solidification time during cooling, and so-called “sink” occurs on the surface side of the base material body. It becomes difficult to do.

Furthermore, according to the present invention, the resin product itself can be reinforced by the rib corresponding to the gate, and the strength and rigidity are increased. According to the second aspect of the present invention, first, the sheet material is set on the setting surface of the mold. Further, a cavity is formed by the alignment between the first molding surface of the first mold and the second molding surface of the second mold that is disposed so as to be able to approach and separate from the first mold. You. Then, the plasticized resin material is injected into the cavity through a gate provided in the second mold. As a result, a resin product having a base body made of a thermoplastic resin and a sheet material that is thermally fused to a part of the surface of the base body is obtained.

Also in the present invention, the gate is formed in a flat shape, and the rib protruding from the base material body to the rear surface side is integrally formed by the resin material existing in the gate. For this reason, similarly to the first aspect of the present invention, "sink" is unlikely to occur, and the sheet material is prevented from being damaged. Further, the strength and rigidity of the resin product itself can be increased by the rib corresponding to the gate.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will now be described with reference to FIGS.
7 will be described. As shown in FIG. 2, an instrument panel (hereinafter referred to as “instrument panel”) 1 as a resin product around an instrument panel is disposed in front of a driver's seat and a passenger seat of an automobile. The instrument panel 1 includes a substrate body 2
And an elastic sheet material 3 attached to an upper surface thereof (a hatched portion in the figure). That is, the instrument panel 1 of the present embodiment is of a “half pad type” which is often used in public cars, and a part of the base material body 2 is exposed.

As shown in FIG. 3, the base material main body 2 is made of a polypropylene mixed with a filler (P with filler).
P), and a predetermined rigidity is ensured. Further, the elastic sheet material 3 is arranged in order from the inner layer side (the lower side in the figure), a heat fusion layer 4 made of PP, and the outer side of the heat fusion layer 4 (the upper side in the figure), and a cushion made of PP foam. Layer 5 and the outer side of the cushion layer 5, polyvinyl chloride (PV)
The solid skin layer 6 made of C) is integrally formed. In this embodiment, the heat-sealing layer 4 of the elastic sheet material 3 is bonded to the upper surface of the base body 2 by heat-sealing, so that the elastic sheet material 3 and the base body 2 are bonded together.
And the adhesion between them is ensured.

As shown in FIG. 1, the base body 2 is integrally formed with a rib 7 protruding toward the back side (left side in the figure). The plurality of ribs 7 are provided at predetermined intervals. In this embodiment, the thickness of the rib 7 is “3 to 5 m”.
m ”.

Next, the mold apparatus 11 for molding the base body 2 of the instrument panel 1 will be described. As shown in FIG. 4, the mold apparatus 11 includes a movable mold 12 that forms a first mold and a fixed mold 13 that forms a second mold. The movable mold 12 is provided so as to be able to approach and separate from the fixed mold 13. In addition, the movable mold 12 has a first molding surface 14 for forming a part of the base body 2,
It has a setting surface 15 on which the elastic sheet material 3 is set. Furthermore, the fixed mold 13 has a second molding surface 16. The movable mold 12 and the fixed mold 13 are in contact with each other, and the first molding surface 14 and the second molding surface 16 are aligned to form a cavity 17 for forming the base body 2. You.

In addition, in the present embodiment, a plurality of (only one is shown in the figure) gates 21 opening into the cavity 17 communicate with the fixed mold 13 and the end faces of the gate 21 and the fixed mold 13. A runner 22 is formed.

The gate 21 is formed substantially parallel to the moving direction of the movable mold 12. The gate 21 has a substantially rectangular cross section, and its width corresponds to the thickness of the rib 7. In other words, the gate 21 is a communication path for injecting the resin material into the cavity 17 and also has a role as a part of the cavity 17 for forming the rib 7. Further, the gate 21
Are formed sufficiently wide so that the resin material passing therethrough is diffused.

Next, in the embodiment, the instrument panel 1
A method of manufacturing the device will be described. First, the elastic sheet material 3 is manufactured in advance. That is, a planar sheet having the above three-layer structure is obtained. Next, the instrument panel 1 is formed into a shape conforming to the shape of the upper surface of the instrument panel 1 by a known vacuum forming method.
Thereafter, excess portions are cut and removed by trimming.
Through these series of steps, the elastic sheet material 3 is obtained.

Then, as shown in FIG. 5, the preformed elastic sheet material 3 is set at a predetermined position in the cavity 17 of the mold apparatus 11. More specifically, the elastic sheet material 3 is brought into contact with the set surface 15 of the movable mold 12 in a state where the molds 12 and 13 are opened, and then the movable mold 12 is brought into contact with the fixed mold 13. At this time, the elastic sheet material 3 is set in a state where the solid skin layer 6 is in contact with the setting surface 15.

Subsequently, as shown in FIGS. 6 and 7, a plasticized filler-containing PP is injected using an injection molding machine (not shown).
(Resin material) is injected into the cavity 17 from the runner 22 through the gate 21. Then, the resin material is filled in the cavity 17. At this time, the heat fusion layer 4 is softened by the heat of the resin material. Thereafter, the resin material is cooled and solidified, so that the heat-fusion layer 4 is fused with the resin material. By this fusion, the elastic sheet material 3 and the resin material (base body 2) are joined. And both types 12,1
When the mold 3 is opened and the base body 2 to which the elastic sheet material 3 is attached is taken out, the instrument panel 1 in which the ribs 7 are integrally formed on the back surface of the base body 2 is obtained.

In the instrument panel 1 thus obtained, a predetermined rigidity is ensured by the base body 2 made of the filler-containing PP. In addition, the cushion layer 5 of the elastic sheet material 3 attached to a part of the base body 2 ensures a soft feeling when touched, and the solid skin layer 6 provides anti-glare property, weather resistance, heat resistance, Appearance quality etc. are ensured. Furthermore, the adhesiveness between the elastic sheet material 3 and the base material body 2 is ensured by the heat sealing layer 4.

In the present embodiment, the injected resin material is once diffused in the gate 21 and then filled in the cavity 17. At this time, the resin material hardly hits the elastic sheet material 3 directly, so that the pressure and heat of the resin material are prevented from being directly and locally applied. Therefore, it is possible to prevent the elastic sheet material 3 from being damaged by the pressure and the heat. As a result, it is possible to prevent the appearance quality from being degraded due to damage to the elastic sheet material 3.

Further, the gate 21 is formed in a substantially rectangular shape, and the rib 7 projecting from the base body 2 to the rear surface side is integrally formed by the resin material existing in the gate 21. For this reason, since the base portion of the surplus portion corresponding to the gate 21 is formed in a flat shape (thin shape), there is no large difference in solidification time during cooling, and So-called "sink" is less likely to occur. As a result, it is possible to prevent the appearance quality from deteriorating due to sink marks.

In addition, according to the present embodiment, the gate 2
With the ribs 7 corresponding to 1, the instrument panel 1 itself can be reinforced. Therefore, at the same time as the above effects, strength,
The effect that the rigidity can be increased is also exerted.

In addition, in this embodiment, unlike the prior art in which the resin material corresponding to the gate is an excess part,
The resin material corresponding to the gate 21 can be used as a part of the instrument panel 1. For this reason, the generation of excess resin material can be minimized, and the yield can be improved.

The present invention may be implemented as follows, with a part of the configuration being appropriately changed. (1) In the above embodiment, the base material main body 2 is made of PP containing filler.
However, it may be composed only of PP. Further, it may be made of a thermoplastic resin (for example, an ABS resin or the like) having a predetermined rigidity at the time of solidification.

Further, in the above embodiment, the elastic sheet material 3
Is composed of the heat-sealing layer 4, the cushion layer 5, and the solid skin layer 6, but may be formed of any number of layers as long as the material can be used as the skin, and the material is not limited at all. is not. Therefore, a sheet material having only the skin layer without the cushion layer 5 may be used.

(2) The fixed mold 13 and the movable mold 12 in the above embodiment may be turned upside down in the drawing. (3) In the above embodiment, the instrument panel 1 is employed as the resin product. However, the instrument panel 1 may be embodied as a resin product such as a door trim, a side garnish, or a pillar garnish.

(4) In the above embodiment, the ribs 7 are provided at a plurality of positions. However, the ribs 7 may be provided at at least one position. (5) In the above-described embodiment, the cross-sectional shape of the rib 7 is substantially rectangular. However, the cross-sectional shape is not particularly limited. What is necessary is just a flat shape which can be comprised. Therefore, for example, the cross-sectional shape of the gate may be curved, or may be a shape having a part that protrudes partially.

(6) A part of the rib 7 in the above embodiment can be cut into a desired shape and a desired size. The technical ideas which are not described in each claim of the claims but can be grasped from the above embodiments are described below together with their effects.

(A) In the method for manufacturing a resin product or the molding die apparatus according to claim 1 or 2, the gate is
It is characterized in that it is provided at a plurality of places at predetermined intervals. With this configuration, the strength of the resin product,
A significant increase in rigidity can be achieved.

(B) In the method for manufacturing a resin product or the molding die apparatus according to (1) or (2) or (a), the base material and the sheet material may be applied to the base material body. The portions in contact with each other are characterized by using the same material as a main component. With such a configuration, it is possible to improve the joining force between the two.

[0037]

As described in detail above, according to the first or second aspect of the present invention, a method of molding a resin article having a base material body and an elastic sheet material heat-sealed to the surface thereof, and the molding thereof In the mold apparatus for use, it is possible to suppress the occurrence of sink marks and the damage to the sheet material due to the molding, and thus to provide an excellent effect that the deterioration of the appearance quality can be surely prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an instrument panel according to an embodiment of the present invention.

FIG. 2 is a perspective view of an instrument panel in one embodiment.

FIG. 3 is an enlarged cross-sectional view of the instrument panel in one embodiment.

FIG. 4 is a sectional view showing a mold apparatus for molding an instrument panel in one embodiment.

FIG. 5 is a cross-sectional view showing a state where a sheet material is set inside a mold apparatus for instrument panel molding in one embodiment.

FIG. 6 is a cross-sectional view showing a portion of the mold apparatus where a gate is present in a state where resin is injected into a cavity in one embodiment.

FIG. 7 is a cross-sectional view showing a portion of the mold apparatus where no gate is present in a state where resin is injected into the cavity in one embodiment.

FIG. 8 is an enlarged sectional view showing a part of an instrument panel according to a conventional technique.

FIG. 9 is a cross-sectional view illustrating a mold apparatus for molding an instrument panel according to a conventional technique.

FIG. 10 is an end view showing a gate opening portion of a mold apparatus for instrument panel molding in the prior art.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Instrument panel (instrument panel) as a resin product, 2 ... Substrate main body, 3 ... Elastic sheet material as a sheet material, 7 ... Rib, 11 ... Mold device, 12 ... Movable as a first mold Mold, 13 ... fixed mold as second mold, 14
.., First molding surface, 15... Setting surface, 16... Second molding surface, 17... Cavity, 21.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-255312 (JP, A) JP-A-5-2927 (JP, U) JP-A 55-5244 (JP, U) 32818 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B29C 45/00-45/84

Claims (2)

(57) [Claims] 1. A method for molding a resin product comprising a base material body (2) made of a resin material and a sheet material (3) heat-sealed to a part of the surface thereof. 3) forming the sheet material (3) into a predetermined shape by a vacuum forming method;
5) and a first mold (12) having a first molding surface (14) for forming a part of the base body (2).
And a second molding surface (16), which is disposed so as to be relatively movable toward and away from the first mold (12) and forms the remaining portion of the base body (2). The second mold (13)
Preparing a mold apparatus (11) consisting of: a sheet material (3) in a state where the surface of the sheet material (3) is substantially in contact with the set surface (15) of the first mold (12); Setting a material (3) in a cavity (17) constituted by the first molding surface (14) and the second molding surface (16); and placing the plasticized resin material in the second metal. A step of injecting and filling the cavity (17) from at least one gate (21) provided in the mold (13), and a step of thermally bonding the sheet material (3) to a part of the surface. Removing the material body (2) from the mold apparatus (11), forming the gate (21) in a flat shape, and using a resin material existing in the gate (21). A rib (7) projecting from the base body (2) to the back side Method of molding a resin product characterized in that in order to form. 2. A resin product comprising: a base material body (2) made of a thermoplastic resin; and a sheet material (3) heat-sealed to a part of the surface of the base material body (2). A mold apparatus for molding (1), wherein a set surface (1) on which the sheet material (3) is partially set.
5) and a first mold (12) having a first molding surface (14) for forming a part of the base body (2).
And a cavity for forming the base body (2) by alignment with the first molding surface (14), the cavity being arranged to be relatively movable toward and away from the first mold (12). A gate for providing a second molding surface (16) constituting (17) and for injecting a plasticized resin material for forming the base material body (2) into the cavity (17). A second mold (13) having (21), and a rib () protruding from the base body (2) to the back surface side by the resin material existing in the gate (21). A molding apparatus for molding a resin product, wherein the gate (7) is formed in a flat shape so that the gate (7) is integrally formed.