JPH03278912A - Manufacture of resin molded product with insert - Google Patents

Abstract

PURPOSE:To improve a quality of a design surface and reduce a positional deviation of an insert, by a method wherein a skin resin material is arranged in a cavity of a mold for molding the design surface of a resin molded product, a main body resin material in a plasticized state, into which the insert is laid is pressurized within the cavity and fused to the skin resin material. CONSTITUTION:At the time when a main body resin material 1 and insert 2 are co-extruded through a die head of an extrusion molding machine, a main body resin material 1 is extruded thicker than a depth of a cavity 28 and the insert 2 of the inside of the same is laid. Then the main body resin material 1 and insert 2 are cut into fixed lengths which are shorter than that of the cavity 28 and conveyed to a mold unit 23. On the other hand, a skin resin material 7 is put on the cavity 28 of a stationary mold 24 by a film feeder 31, in a mold unit 23. Then, a movable mold 25 is clamped to the stationary mold 24, the main body resin material 1 is pressurized, deformed easily by pressing force of the movable mold 25, filled into the whole area of the inside of the cavity 28 and fused to the skin resin material 7. Both ends surfaces of the insert is concealed with the pressurized and deformed main body resin material 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing resin molded products such as automotive moldings, and particularly relates to a method for manufacturing resin molded products such as moldings for automobiles, and in particular, an insert in which an insert for preventing expansion/contraction or for reinforcing is embedded in a main resin material. The present invention relates to a method for manufacturing a filled resin molded product.

[Prior Art] For example, a molding for an automobile is usually formed into a long shape by extrusion molding or injection molding, but when this long molding for a car is attached to a car body, the molding for an automobile and the car body are Due to the difference in linear expansion coefficients, the automotive molding may expand or contract and float off the vehicle body. In order to prevent such a phenomenon, a technique has been proposed in which an insert is buried in the resin material of the main body of an automobile molding.

FIG. 7 is a partially cutaway perspective view of a conventional insert-containing molding for an automobile.

As shown in the figure, when molding an automobile molding by extrusion molding, a main body resin material 1 and an insert 2 are co-extruded from a die head (not shown) of an extrusion molding machine, and a designed surface is formed on the front side of the main body resin material 1. A vehicle body mounting surface 6 is formed on the back side of 5, and an insert 2 is embedded therein.

After this extrusion molded product is cut to a required length, both ends are set in an injection mold (not shown), and the terminal member 3 is connected and molded therein. In this way, the cut surfaces of the main body resin material 1 and the insert 2 can be hidden by the terminal member 3, and the overall length of the automotive molding can be determined accurately. In the case of injection molding, the main resin material is injected with the insert set in the cavity of the injection mold.

[Problems to be Solved by the Invention] However, according to the conventional extrusion molding method for producing an insert-containing resin molded product, as described above, the terminal member 3 is injection molded after extrusion, so the main body resin material 1 and the terminal member are A weld line 4 appears at the connection with 3, and the design surface 5
There was a problem that the appearance of the image deteriorated. In addition, injection molding not only requires a complicated and expensive injection mold in which to set the insert, but also causes the insert to shift and become exposed due to injection pressure, or to cause visual defects such as short shots or flow marks. The problem was that it was easy to use. Furthermore, in both extrusion and injection methods, the main body resin material 1 is exposed as it is to form the designed surface 5, making it difficult to use recycled synthetic resin material as a raw material.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a resin molded article containing an insert, which can improve the quality of the design and has less displacement of the insert.

[Means for Solving the Problems] In order to solve the above problems, the method for manufacturing a resin molded product with an insert of the present invention includes a step of placing a skin resin material in a cavity for molding a design surface of a resin molded product, burying an insert shorter than the length of the cavity in the main body resin material and placing it overlapping the skin resin material in the cavity; , the step of pressurizing the plasticized main body resin material in which the insert is embedded in the cavity to fuse it to the skin resin material.

[Function] According to the method of manufacturing a resin molded article with an insert according to the present invention, the main resin material, which is thicker than the depth of the cavity and has a volume approximately equal to the volume of the cavity, is deformed under pressure within the cavity, so that the main resin material is deformed under pressure within the cavity. The material fills the entire area of the cavity without any gaps, and the skin resin material forms a designed surface in close contact with the molded surface of the cavity. therefore,
There is no risk of appearance defects such as short shots or flow marks occurring on the design surface of resin molded products.

Furthermore, since the insert is shorter than the cavity, when the main body resin material is deformed under pressure, a portion thereof hides both end surfaces of the insert. Therefore, unlike the case of conventional extrusion molding, there is no need to mold the terminal member in a separate process. Moreover, since the main body resin material is covered with the skin resin material, relatively inexpensive recycled synthetic resin materials can be used as raw materials for the main body resin material, and even in this case, there is no risk of appearance defects on the design surface. .

[Example] Hereinafter, an example in which the present invention is embodied in a method for manufacturing an insert-containing automotive molding will be described based on the drawings.

<First Embodiment> FIGS. 1 to 5 show a method for manufacturing an insert-containing automotive molding according to a first embodiment of the present invention, and FIG. 1 is a plan view showing the entire implementation apparatus, and FIG. The figure is A- in Figure 1.
3 is an enlarged sectional view taken along line B-B of FIG. 1 showing the process of arranging the skin resin material and the main body resin material in the cavity, and FIG. 4 is a cross-sectional view taken along the line B-B of FIG. FIG. 1 is an enlarged cross-sectional view taken along the line B--B in FIG. 1 showing the pressure deformation process, and FIG. 5 is a partially cutaway perspective view of a molding for an automobile molded by the manufacturing method of the first embodiment.

As shown in FIG. 5, the automotive molding molded by the manufacturing method of the first embodiment includes a main body resin material 1 on which a vehicle body mounting surface 6 is formed on the back side, and a body resin material 1 embedded in the main body resin material 1. an insert 2 for preventing expansion and contraction of an automobile molding;
It is composed of a skin resin material 7 that covers the entire surface of the main body resin material 1 to form a design surface 5 of the automobile molding.

As for the material of the main body resin material 1, soft polyvinyl chloride (PVC) is suitable for side moldings, but other materials such as polypropylene resin (PP), polyethylene resin (PE), or acrylonitrile resin may also be used depending on the purpose. Various thermoplastic synthetic resin materials such as genstyrene copolymer resin (ABS) can be used.

The material of the insert 2 is a tape-shaped metal material such as aluminum, stainless steel or steel, or FRP.
The cross-sectional shape is not limited to the linear shape shown in FIG. 5, but may be wavy or U-shaped. Further, in order to improve the adhesion between the insert 2 and the main body resin material 1, the insert 2 may be previously subjected to surface treatment such as sandblasting, paper polishing, or primer coating.

In this first embodiment, the skin resin material 7 has a thickness of 0.2 to 2. A synthetic resin film or a foamable synthetic resin film with a thickness of approximately 0 mm is used, and basically, a material that is the same as the main body resin material 1 and which can be fused and integrated is suitable.

To explain the apparatus for manufacturing the automotive molding having the above configuration, in FIGS. 1 and 2, 11 is an extrusion molding machine, and is equipped with a material supply hopper 12 and a die head 13. 14 is an insert support roll, and the insert 2 wound around this roll is supplied to the die head 13 by a supply machine 15. Die head 13 is made of main body resin material 1
and the insert 2 are co-extruded to embed the insert 2 in the main resin material 1.

16 is a first conveyor that conveys the main body resin material 1 with the insert 2 embedded therein; 17 is a cutting machine that cuts the main body resin material 1 and the insert 2 to a predetermined length; and 18 is a drawing of the main body resin material 1 from the cutting machine 17. This is the second conveyor that will then stop. Reference numeral 19 denotes a conveyor that feeds the main body resin material 1 on the second conveyor 18 to a mold unit 23, which will be described later.
It is equipped with a cylinder 21 etc. that reciprocates back and forth.

23 is a mold unit for molding the automotive molding into the final product shape, and as shown in FIGS. 1, 3, and 4, it includes a fixed mold 24, a movable mold 25, a guide column 26, It is composed of a tightening cylinder 27 and the like. Fixed mold 24
A cavity 28 is recessed in the upper part, and the design surface 5 of the automobile molding is formed by the bottom surface of the cavity 28. Movable mold 2
A convex surface 29 that forms the vehicle body mounting surface 6 of the automobile molding is provided at the lower part of the molding.

Reference numeral 31 denotes a film feeder that places the skin resin material 7 made of a synthetic resin film onto the cavity 28 of the fixed mold 24, and includes a film feed roll 32 and a film take-up roll 33 arranged on both sides of the mold unit 23. It consists of

Next, a method of manufacturing the insert-containing molding for an automobile according to the first embodiment will be explained.

As shown in FIGS. 1 and 2, the main resin material 1 and the insert 2 are coextruded from a die head 13 of an extruder 11. As shown in FIGS. At this time, the main resin material 1 is inserted into the cavity 28.
The insert 2 is extruded to a depth greater than the depth of the insert 2.

The material extruded from the die head 13 is transferred to the first conveyor 16
is transported to the cutting machine 17, where the main resin material 1
The insert 2 is then cut to a predetermined length shorter than the length of the cavity 28. The cutting length in this case is determined based on the cross-sectional area of the main resin material 1 so that the volume of the main resin material 1 is approximately equal to the volume of the cavity 28 . Then, the main body resin material 1 after cutting is transferred to the second conveyor 18.
When the body resin material 1 is placed on the mold unit 23, the suction unit 20 and cylinder 21 of the conveyor 19 are activated, and the main body resin material 1 is transferred to the mold unit 23.
Transport to.

Prior to conveying this main body resin material 1, the mold unit 23
, the skin resin material 7 is fed by the film feeder 31.
is placed on the cavity 28 of the fixed mold 24.

Therefore, as shown in FIG. 3, the main body resin material 1 is placed in the cavity 28 by the conveyor 19 so as to overlap the skin resin material 7.

Subsequently, as shown in FIG. 4, the movable mold 25 is clamped to the fixed mold 24 by the mold clamping cylinder 27. At this time, since the main body resin material 1 is in a plasticized state due to the heating in the extrusion process, it is easily deformed under pressure by the pressing force of the movable mold 25, and the entire interior of the cavity 28 is filled.
It is fused to the skin resin material 7. And skin resin material 7
is brought into close contact with the bottom surface of the cavity 28, and the design surface 5 is molded on the front side thereof, and the vehicle body mounting surface 6 is molded on the back side of the main body resin material 1 by the convex surface 29 of the movable mold 25. Further, at this time, the skin resin material 7 is cut along the periphery of the convex surface 29 of the movable mold 25. In addition, in order to facilitate this cutting, the cavity 2 is used as the skin resin material 7.
It is also possible to use a shaped film provided with a perforation line having the same shape as 8.

This pressurizing process is continued at a predetermined pressure and time depending on the size and material of the automotive molding, and during this period, the main resin material 1 is cooled and solidified. Thereafter, the fixed mold 24 and the movable mold 25 are opened, and the molded product of the automobile molding is taken out from the cavity 28, and then the film feeder 3
The cutout portion 34 (
(see FIG. 1) is wound up, and the next body resin material 1 containing an insert 2 is placed on the new skin resin material 7.

Note that if the cut edges of the skin resin material 7 are irregular, trimming processing is performed in a separate process.

As described above, in the method for manufacturing an automobile molding with an insert according to the first embodiment, a skin resin made of a synthetic resin film is applied by a film feeder 31 to the cavity 28 in which the design surface 5 of the automobile molding as a resin molded product is formed. A process of arranging the material 7, a process of co-extruding the main body resin material 1 and the insert 2 from the die head 13 of the extrusion molding machine 11, and embedding the insert 2 in the main body resin material 1, a process of embedding the main body resin material 1 and the insert by the cutting machine 17. 2 into cavity 28
a step of cutting the main resin material 1 to be shorter than the length of the cavity 28, a step of placing the main resin material 1 thicker than the depth of the cavity 28 and having a volume almost the same as the volume of the cavity 28 over the skin resin material 7 in the cavity 28 using the conveyor 19; insert 2
The main body resin material 1 in a plasticized state in which is embedded is placed in a movable mold 2.
5, the body resin material 1 is pressurized and deformed in the cavity 28 to fuse the main body resin material 1 to the skin resin material 7.

Therefore, according to the method of manufacturing an insert-containing automotive molding according to the first embodiment, the main resin material 1 which is thicker than the depth of the cavity 28 and has approximately the same volume as the volume of the cavity 28 is deformed under pressure within the cavity 28. , the entire cavity 28 is filled with the main body resin material 1 without any voids. At this time, the skin resin material 7 is reliably fused to the main body resin material 1 in close contact with the molding surface of the fixed mold 24 by the pressing force. Since the designed surface 5 of the automobile molding is formed from this skin resin material 7, there is no risk of appearance defects such as short shots and flow marks occurring on the designed surface 5.

In addition, the insert 21 is shorter than the cavity 28, and both end surfaces thereof are hidden by the main body resin material 1 that has been deformed under pressure. Therefore, unlike conventional extrusion molding, it is necessary to mold the terminal member in a separate process. It disappears. Moreover, since the main body resin material 1 is covered with the skin resin material 7, a relatively inexpensive recycled synthetic resin material can be used as the raw material for the main body resin material 1, and even in this case, there is no appearance defect on the design surface 5. There is no risk of this happening.

<Second Embodiment> Next, a second embodiment of the present invention will be described based on FIG. 6.

FIG. 6 is a process explanatory diagram showing a method of manufacturing an insert-containing molding for an automobile according to a second embodiment of the present invention. In addition,
In the drawings, the same reference numerals as in the first embodiment indicate the same or corresponding components as in the first embodiment.

In this second embodiment, first, as shown in FIG. 6(a), the cavity 28 of the fixed mold 24 is mold-coated with a synthetic resin material to a thickness of about 0.2 to 2.0 mm. The skin resin material 7 is arranged by. If the peripheral edge of the skin resin material 7 is irregular, it may be trimmed at this point, or it may be trimmed after the molding is completed.

Next, as shown in FIG. 6(b), the first divided piece 1a, which is in a plasticized state immediately after extrusion molding, is placed on top of the skin resin material 7.

Next, as shown in FIG. 6(c), an insert 2 shorter than the length of the cavity 28 is placed on the first divided piece 1a.

Subsequently, as shown in FIG. 6(d), the second divided piece 1b, which is in a plasticized state immediately after extrusion molding, is placed over the first divided piece 1a, sandwiching the insert 2 therebetween.

In this second embodiment, the main body resin material 1 consists of the first divided piece 1a and the second divided piece lb, and when they are stacked, the resin material 1 is thicker than the depth of the cavity 28 and has approximately the same volume as the cavity 28. It has volume.

Then, as shown in FIG. 6(e), when the movable mold 25 is clamped to the fixed mold 24, the first divided piece 1a and the second divided piece lb in the plasticized state are placed in the cavity 28. They are deformed under pressure and fused together, and in this state, the insert 2 is embedded in the main resin material 1, and the main resin material 1 is fused to the skin resin material 7.

When the main body resin material 1 is cooled and solidified after a predetermined pressurizing period, the fixed mold 24 and the movable mold 25 are opened, and the molded product of the molding for an automobile is taken out from the cavity 28.

In this manner, the method for manufacturing the insert-containing molding for an automobile according to the second embodiment is such that the process of pressurizing and deforming the main body resin material 1 and the process of embedding the insert 2 are carried out simultaneously.

With this, as in the first embodiment, the skin resin material 7 can be brought into close contact with the molding surface of the cavity 28 to improve the quality of the design surface 5, and the recycled synthetic resin material can be used.
This has the effect of reducing raw material costs. In addition, in the case of this second embodiment, as shown in FIG. 6(e), the first
Since the weld lines 36 of the divided piece 1a and the second divided piece 1b are hidden by the skin resin material 7, there is no risk that the appearance of the designed surface 5 will deteriorate.

In the above example, the present invention is embodied in a method for manufacturing a molding for an automobile, but the present invention is not limited to this. It is also possible to apply this method to various resin molded products in which an insert is embedded.

[Effects of the Invention] As described above, the method for manufacturing a resin molded product with an insert according to the present invention includes the step of placing a skin resin material in the cavity of a mold for molding the design surface of the resin molded product, and a step of embedding an insert shorter than the length of the cavity in the main body resin material, and arranging a main body resin material thicker than the main body resin material and having a volume approximately the same as the volume of the cavity, overlapping the skin resin material in the cavity; The main body resin material in a plasticized state in which the insert is embedded is pressurized in the cavity and fused to the skin resin material.The main body resin material is deformed under pressure and fills the entire cavity without any voids. In addition, the quality of the design of the resin molded product can be improved by bringing the skin resin material into close contact with the molding surface of the mold. Furthermore, there is less misalignment of the insert setting position, and both end faces of the insert can be hidden with the main body resin material, eliminating the process of molding the terminal member.Moreover, the main body resin material can be recycled at a relatively low cost. The use of synthetic resin material has the effect of reducing raw material costs.

[Brief explanation of the drawing]

1 to 5 show a method for manufacturing a molding for an automobile with an insert according to a first embodiment of the present invention, FIG. 1 is a plan view showing the entire implementation device, and FIG. 2 is a 3 is an enlarged sectional view taken along line B-B of FIG. 1 showing the process of arranging the skin resin material and the main body resin material in the cavity, and FIG. 4 is a cross-sectional view taken along the line B-B of FIG. FIG. 1 is an enlarged cross-sectional view taken along the line B--B in FIG. 1 showing the pressure deformation process, and FIG. 5 is a partially cutaway perspective view of a molding for an automobile molded by the manufacturing method of the first embodiment. FIG. 6 is a process explanatory diagram showing a method of manufacturing an insert-containing molding for an automobile according to a second embodiment of the present invention. FIG. 7 is a partially cutaway perspective view of a conventional insert-containing molding for an automobile. In the figure, body resin material 2: insert 5: design surface
7: Skin resin material 28: Cavity. In the drawings, the same reference numerals and the same symbols indicate the same or equivalent parts.

Claims (1)

[Claims] A step of arranging a skin resin material in a cavity of a mold for molding a design surface of a resin molded product; , embedding an insert shorter than the length of the cavity in the main body resin material and arranging it overlapping the skin resin material in the cavity; and processing the plasticized main body resin material in which the insert is embedded in the cavity. A method for manufacturing a resin molded article containing an insert, comprising a step of pressing and fusing it to a skin resin material.