JP2827775B2 - Manufacturing method of resin products - 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 manufacturing a resin product by integrally molding first and second resin materials.

[0002]

2. Description of the Related Art Conventionally, in order to integrally mold different resin materials, a molding apparatus is used as follows.
That is, as shown in FIG. 8, the mold apparatus 41 includes a fixed mold 42 on the upper side in the figure, a movable mold 43 on the lower side in the figure, and a movable mold 4.
3 and a slide core 44 that can move up and down. Then, the fixed mold 42 and the movable mold 43 are clamped to each other, and at this time, the slide core 44 is arranged with the upper end thereof in contact with the fixed mold 42. In this state, the first cavity 45 is formed by the fixed mold 42, the movable mold 43, and the slide core 44.

Next, from that state, as shown in FIG.
The first cavity 45 is injected and filled with a first resin material 46 from a gate (not shown). Then, after the filling is completed, as shown in FIG. 10, the slide core 44 is moved downward in the figure. With this movement, a second cavity 47 is formed by the fixed mold 42, the movable mold 43, the slide core 44, and the first resin material 46. Subsequently, FIG.
As shown in FIG. 1, a second resin material 48 is injected and filled into the second cavity 47 from a gate (not shown). As a result, the first and second resin materials 46 and 48 are integrally joined and molded. Thereafter, the fixed mold 42 and the movable mold 43 are opened, so that the two resin materials 46,
48 are joined to form an integrated resin material.

[0004]

However, after the first cavity 45 is filled with the first resin material 46,
The first resin material 46 is cooled and solidified. At this time, the first resin material 46 slightly shrinks. For this reason, in the above-mentioned prior art, as shown in FIG. 12, there is a possibility that a slight gap S is generated between the fixed mold 42 and the first resin material 46. If the gap S is generated, the second resin material 48 enters the gap S when the second resin material 48 is injected, and burrs are formed on the resulting product. There was a risk of occurrence. As a result, burrs may be generated on the design surface of the product, and the design of the product may be impaired.

[0005] Further, in molding in the above-mentioned prior art,
In order to cool and solidify the two resin materials, the fixed mold 42 and the movable mold 43 are cooled by cooling water.
The temperature of No. 3 is maintained at, for example, about “30 ° C.”. For this reason, when the second resin material 48 injected into the second cavity 47 comes into contact with the first resin material 46, the temperature at the contact surface may be relatively low. In this case, the joining force between the two 46 and 48 is relatively low, and as a result, the second resin material 48 may be easily peeled off from the first resin material 46.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In a method for manufacturing a resin product obtained by integrally molding a first resin material and a second resin material, a burr is formed on a design surface. It is an object of the present invention to provide a method of manufacturing a resin product capable of obtaining a resin product in which first and second resin materials are firmly joined without causing the generation.

[0007]

In order to achieve the above-mentioned object, the present invention provides a first resin material and a second resin material partially fused to the first resin material. A method of manufacturing a resin product to be integrally molded, wherein a first cavity is formed by a fixed mold, a movable mold, and a slide core provided on one of the fixed mold and the movable mold. A step of filling the cavity with the molten first resin material, and after the completion of the filling of the first resin material, a damping projection provided on one of the fixed mold or the movable mold to form the resin product. The slide core is moved so that a part of the first resin material is not exposed on the design surface side, and the fixed mold, the movable mold, the slide core, and the first resin material are moved. Forming a second cavity by: The temperature of both the cavity-side of Raidokoa while higher than the fixed mold and the movable mold,
Filling the second cavity with the molten second resin material.

[0008]

According to the above construction, the first cavity formed by the fixed mold, the movable mold and the slide core is filled with the molten first resin material. After the filling of the first resin material is completed, the first protrusion is provided on one of the fixed type and the movable type on the design surface side of the resin product.
The slide core is moved so that a part of the resin material is not exposed. By this movement, a second cavity is formed by the fixed mold, the movable mold, the slide core, and the first resin material. Then, the molten second resin material is filled in the second cavity in a state where the temperatures of both cavities of the slide core are higher than those of the fixed mold and the movable mold. As a result, a resin product in which the first and second resin materials are joined to each other by fusion is obtained.

At this time, the second resin material flowing in the second cavity is blocked by the blocking projection so as not to hit a part of the first resin material on the design surface side of the resin product. Therefore, even if a slight gap occurs between the fixed or movable mold and the first resin material, the second resin material is prevented from entering the gap.

In addition, when the second resin material is filled, the temperatures of both cavities of the slide core are higher than those of the fixed mold and the movable mold, so that the first and second resin materials come into contact with each other. Temperature is maintained at a relatively high value. Therefore, the abutting portions of the two resin materials are kept in a molten state, and the two resin materials are firmly fused.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method of manufacturing a resin product according to the present invention will be described in detail with reference to FIGS.

FIG. 5 is a perspective view showing a state in which a cowl louver top 1 as a resin product in the present embodiment is arranged in an automobile 2, and FIG. 6 is a perspective view showing one of the cowl louver tops 1. The cowl louver top 1 is composed of left and right divided pieces 3 and 4, which are connected to each other at a connecting portion 5. In the width direction of the automobile 2, a large number of air holes 6 are formed vertically and horizontally in a central portion of the cowl louver top 1, and each air hole 6 is covered by a net 7. A glass fitting groove 9 for fitting a windshield 8 is formed on one side edge (upper edge in FIG. 6) of the cowl louver top 1.

FIG. 7 is a sectional view taken along line AA of the divided piece 3 of FIG. In the figure, the left end of the divided piece 3 is a glass fitting groove 9 into which the windshield 8 is fitted.
The divided piece 3 of this embodiment includes a main body 10 made of a different resin material and a hook-shaped edge 11 having a glass fitting groove 9. That is, the main body 10 is made of a relatively hard first resin material 12 such as fiber-reinforced polypropylene. On the other hand, the edge 11
It is made of a relatively soft second resin material 13 such as SEBS (styrene-ethylene-butylene-styrene copolymer resin) because it comes into contact with the windshield 8.
Further, an engagement protrusion 14 is formed on the main body 10, and the cowl louver top 1 is engaged with the body of the automobile 2 by the engagement protrusion 14.

Next, the cowl louver top 1 as described above.
A mold apparatus for molding the divided pieces 3 and 4 will be described. FIG. 1 is a sectional view showing a part of the molding apparatus. The mold device 21 includes a fixed mold 22 on the upper side of FIG.
And a movable mold 23 on the lower side of the figure. When the movable mold 23 is moved in the vertical direction, both molds 22 and 2 are moved.
3 are mutually mold-clamped and mold-opened. A space is formed in a part of the movable mold 23, and a slide core 24 that can move in the vertical direction in the figure is provided in the space.

The slide core 24 is for dividing a cavity formed between the fixed die 22 and the movable die 23 into two parts over time. That is, as shown in FIG. 1, the stationary die 22 is integrally formed with a blocking projection 25 projecting in the direction of the movable die 23, that is, downward in the figure. Further, at the upper end of the slide core 24, a partitioning projection 26 extending in the direction of the blocking projection 25 is formed. And both types 2
In a state where the mold projections 2 and 23 are clamped and the partition projection 26 on the upper end of the slide core 24 is arranged in contact with the blocking projection 25 of the fixed mold 22, the main body 10 of the divided pieces 3 and 4 is formed. A first cavity 27 is formed. The first cavity 27 is provided with a projection space 28 for molding the engagement projection 14 of the main body 10 described above.

The fixed mold 22 has a first cavity 2.
7, a first gate 29 for injecting the first resin material 12 is provided. On the other hand, as shown by the two-dot chain line in FIG. 2, when the slide core 24 is moved downward, a second cavity 30 for molding the edge 11 is formed adjacent to the first cavity 27. It has become. Further, the fixed mold 22 is provided with a second gate 31 for injecting the second resin material 13 into the second cavity 30.

Further, the middle part of the slide core 24 is formed narrower than other parts, and a heat insulating cavity 32 is formed between the slide core 24 and the movable die 23.
When the second resin material 13 is injected, a portion of the slide core 24 closer to both cavities 27 and 30 (upper side in the drawing) than the heat insulating cavity 32 is made of the first resin material. Due to the heat transfer from 12, the temperature becomes relatively high. A cooling water passage (not shown) is formed in the fixed mold 22 and the movable mold 23. And
Cooling water flows in the water channel, and the temperatures of the fixed mold 22 and the movable mold 23 are always maintained at approximately “30 ° C.”.

Next, a method of manufacturing the divided pieces 3 and 4 performed by using the molding die apparatus 21 configured as described above will be described. Cowl louver top 1 split pieces 3, 4
First, as shown by a solid line in FIG. 1, the fixed mold 22 and the movable mold 23 are mutually clamped, and in this state, the partition projection 26 at the upper end of the slide core 24 is It is arranged in contact with the dam projection 25. By this mold clamping and the like, a first cavity 27 for forming the main body 10 of the divided pieces 3 and 4 is formed by the two dies 22 and 23 and the slide core 24.

Subsequently, as shown in FIG. 2, the first resin material 12 in a molten state is injected from the first gate 29 into the first cavity 27 and filled therein. When the filling is completed, the main body 10 as an intermediate product having the engagement protrusions 14 is formed. At this time, the heat from the first resin material 12 is transmitted to a portion of the slide core 24 closer to both cavities 27 and 30 than the heat insulating cavity 32. Further, since the heat is hardly released by the heat insulating cavity 32, the temperature of the portion of the slide core 24 on both the cavities 27 and 30 becomes higher than that of the fixed mold 22 and the movable mold 23 cooled by the cooling water.

Then, as shown in FIG. 3, the slide core 24 is moved downward in FIG. By this movement, the second cavity 30 for forming the edge 11 by the fixed mold 22, the movable mold 23, the slide core 24 and the main body 10 (first resin material 12) as an intermediate product.
Is formed.

Thereafter, as shown in FIG. 4, the second resin material 13 is injected and filled into the second cavity 30 from the second gate 31. At this time, the second cavity 3
The second resin material 13 flowing in the inside 0 is blocked by the blocking protrusion 25 on the design surface side (upper side in the figure) of the cowl louver top 1 and does not hit a part of the first resin material 12. Therefore, even if a slight gap occurs between the fixed mold 22 and the first resin material 12, the second resin material 13
Does not penetrate into the gap.

When the second resin material 13 is filled,
The two cavities 27 and 30 sides of the slide core 24 are the first
The heat from the resin material 12 is transmitted. Then, the heat is hardly released by the heat insulating cavity 32.
For this reason, both cavities 27 and 30 of the slide core 24
The fixed mold 22 and the movable mold 2 cooled by cooling water
The temperature is higher than 3. Therefore, the temperature of the portion where the first and second resin materials 12 and 13 come into contact with each other is maintained at a relatively high value. Therefore, the contact portion between the two resin materials 12 and 13 is maintained in a molten state, and the two resin materials 12 and 13 are firmly fused. Then, by filling the second resin material 13, the edge 11 having a hook-shaped cross section is joined to the main body 10 and molded.

Finally, after the molded product is cooled and solidified from the above state, the fixed mold 22 and the movable mold 23 are opened to take out the resin molded product, and as shown in FIG. The divided pieces 3 and 4 in which the edge 11 is integrally formed are obtained. Then, the cowl louver top 1 is obtained by connecting the left and right divided pieces 3 and 4 with the connecting portion 5.

As described above, according to the method of manufacturing the cowl louver top 1 of the present embodiment, the blocking projection 25 projecting in the direction of the movable mold 23 is formed on the fixed mold 22. The damping projection 25 allows the second resin material 13 flowing in the second cavity 30 to flow through the cowl louver top 1.
The first resin material 12 is prevented from hitting a part of the first resin material 12 by blocking the design surface side. Therefore, even if a slight gap occurs between the fixed mold 22 and the first resin material 12, the second resin material 13 does not enter the gap. As a result, it is possible to prevent burrs from being generated on the design surface side of the obtained cowl louver top 1 beforehand.

In this embodiment, a heat insulating cavity 32 is formed in the middle of the slide core 24. When the second resin material 13 is injected, the slide core 2
4, both cavities 27,
The portion on the 30 side is heated to a high temperature by the heat transfer from the first resin material 12 and the heat insulating action of the heat insulating cavity 32. Therefore, the temperature of the portion where the first and second resin materials 12 and 13 come into contact with each other is maintained at a relatively high value.
Therefore, the molten state of the contact portion between the two resin materials 12 and 13 can be ensured, and the two resin materials 12 and 13 can be firmly fused and joined.

It should be noted that the present invention is not limited to the above-described embodiment, and may be implemented as follows by appropriately changing a part of the configuration without departing from the spirit of the invention. (1) In the above embodiment, the heat insulating cavity 32 is formed in the middle part of the slide core 24 so that the heat transmitted from the first molten resin material 12 is not released.
For example, a heat insulating material such as glass wool may be provided. In addition, a separate heating means such as a heater may be provided to heat only the slide core 24.

(2) In the above embodiment, the first resin material 1
The second uses fiber-reinforced polypropylene as the second
Although SEBS was adopted as the resin material 13 of its rigidity,
Regardless of its soft nature, any resin material may be used as long as it uses a different resin material.

(3) In the above embodiment, the manufacturing method for forming the divided pieces 3 and 4 of the cowl louver top 1 as a resin product has been embodied. The present invention may be embodied in a manufacturing method for molding an exterior product or an interior product such as an instrument panel.

(4) In the above embodiment, the slide core 24
Is provided on the movable die 23 side, but the slide core 24 may be provided on the fixed die 22 side. Also,
In this case, the blocking protrusion 25 may be provided on the movable mold 23 side.

[0030]

As described above in detail, according to the method for manufacturing a resin product of the present invention, in the method for manufacturing a resin product obtained by integrally molding the first and second resin materials, the design An excellent effect that a resin product in which the first and second resin materials are firmly joined can be obtained without generating burrs.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a part of a cowl louver top molding die apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a cowl louver top in one embodiment.

FIG. 3 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a cowl louver top in one embodiment.

FIG. 4 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a cowl louver top in one embodiment.

FIG. 5 is a perspective view showing a state in which a cowl louver top is arranged in an automobile in one embodiment.

FIG. 6 is a perspective view showing a divided piece of a cowl louver top in one embodiment.

FIG. 7 is a sectional view taken along line AA of FIG. 6 in one embodiment.

FIG. 8 is a cross-sectional view showing a part of a resin product molding die apparatus in the prior art.

FIG. 9 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin product in the related art.

FIG. 10 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin product in the prior art.

FIG. 11 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin product in the related art.

FIG. 12 is a cross-sectional view showing a part of a molding apparatus for molding a resin product for explaining a problem in the related art.

[Explanation of symbols]

1 ... Cowl louver top as a resin product, 12 ... First
Resin material, 13 ... second resin material, 22 ... fixed type, 2
3: movable type, 24: slide core, 25: blocking protrusion, 2
7: first cavity, 30: second cavity.

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takuji Nagata 1 Ochiai Ogaai, Kasuga-cho, Nishikasugai-gun, Aichi Prefecture Toyoda Gosei Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 45 / 00-45/84

Claims (1)

(57) [Claims] A resin for integrally molding a first resin material (12) and a second resin material (13) partially fused to the first resin material (12). A method of manufacturing a product, comprising: a fixed mold (22); a movable mold (23);
2) or a slide cavity (24) provided on one of the movable molds (23) to form a first cavity (27), and the first cavity (27) melted with respect to the first cavity (27). A step of filling the resin material (12), and after the filling of the first resin material (12) is completed, by a blocking projection (25) provided on one of the fixed mold (22) or the movable mold (23). The slide core (24) is moved so that a part of the first resin material (12) is not exposed on the design surface side of the resin product (1),
Forming a second cavity (30) by the fixed mold (22), the movable mold (23), the slide core (24), and the first resin material (12); The two cavities (27,
30) The temperature of the fixed type (22) and the movable type (2)
3), the second cavity (3)
Filling the second resin material (13) melted with respect to 0).