JP2003011156A - Resin outer plate for vehicle and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight and low cost resin outer plate (a hood or the like) for a vehicle, with a presentable appearance. SOLUTION: In a preforming step (a), a skin film 14 with a metallic foil is preformed by tightly holding the film 14 between a top force 34 and a bottom force 32 under pressure. Then in a compression-molding step (b), the top force 34 is made to ascend by a specified size and a molten resin 42 including a glass fiber is packed between the skin film 14 and the bottom force 32. After that, when the surface layer part 12b of the molten resin 42 is slightly cured, the top force 34 is made to further ascend and a gas is injected into the interior 12a of the molten resin 42 and thus an inflation molding step (c) is performed. The interior 12 of the molten resin 42 is inflated into an expanded state by a spring back phenomenon of the glass fiber and the effect of a gas pressure. Consequently, a resin hood is obtained which is constituted of the skin film 14 tightly bonded, in one piece, to the surface of a resin base material 12 of a lightweight and highly rigid outer shell structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular resin outer plate, and more particularly to a technique for ensuring a predetermined rigidity, reducing weight, and manufacturing at low cost.

[0002]

2. Description of the Related Art A hood made of a resin integrally molded with a resin material such as ABS or polystyrene is known as a hood for opening and closing an upper part of a prime mover portion arranged at a front portion of a vehicle. The hood (bonnet) described in Japanese Unexamined Patent Publication No. 10-129526 is an example of the hood. The hood has a hollow outer shell structure by blow molding, and can reduce the weight while ensuring a predetermined rigidity.

[0003]

However, such a resin hood needs to be top-coated (painted) to improve its appearance, which requires expensive coating equipment and increases the manufacturing cost. Further, when a hollow outer shell structure is formed by blow molding, it is necessary to provide a large number of reinforcing parts (connecting parts of front and back panels) in order to ensure a predetermined rigidity, which may impair the surface appearance.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lightweight and inexpensive resin hood for vehicles, which has an excellent appearance.

[0005]

In order to achieve the above object, the first aspect of the present invention manufactures a resin outer panel for a vehicle by using a pair of front surface side molding die and back surface side molding die which are closely spaced from each other. A method, (a) placing a skin film between the front surface side molding die and the back surface side molding die, a preforming step of deforming the skin film along one molding surface, (b) A molten resin material containing reinforcing fibers is supplied between the back side mold and the skin film, and is smaller than the target dimension formed between the back side mold and the front side mold. By maintaining a predetermined compressed state in the cavity, to form a slightly hardened skin layer on the surface layer portion of the molten resin material and at the same time a compression molding step of fixing the skin film to the skin layer,
(c) by separating the front-side mold and the back-side mold before the molten resin material inside the skin layer is cooled and cured, and by injecting a gas into the molten resin material, Expansion molding step of expanding the molten resin material into a foamed state by the action of the springback phenomenon of the reinforcing fiber and the gas pressure to obtain a target dimension.

A second invention is the resin outer panel for a vehicle according to the first invention, wherein (a) the skin film comprises a resin base layer and a metal foil laminated on the surface side of the base layer. It has a laminated structure having, (b) the thickness dimension of the vehicle resin outer plate is substantially constant, the molding surface of the front surface side mold and the back surface side mold have substantially the same shape, c) In the preforming step, the skin film is sandwiched between the back surface side molding die and the front surface side molding die to perform draw forming.

A third aspect of the present invention is the resin outer panel for a vehicle according to the first or second aspect of the invention. (A) The thickness of the vehicle outer panel for a vehicle is substantially constant, and the front side molding die and the The molding surface of the back side molding die has substantially the same shape, and (b) in the preforming step, the skin film is closely adhered to the molding surface of the back side molding die by vacuum suction for preforming. .

A fourth invention is the method for manufacturing a vehicle resin outer panel according to any one of the first to third inventions, wherein the resin material is polypropylene, the reinforcing fiber is glass fiber, and the expansion molding is performed. In the step, the volume of the resin material including the skin layer is expanded to 1.3 to 3 times.

A fifth aspect of the present invention is a vehicle resin outer panel mainly composed of a resin base material, wherein: (a) the resin base material is made of a resin material mixed with reinforcing fibers. In addition to being configured, while the inside has a foamed state and the surface layer has a dense skin layer outer shell structure, (b) the vehicle base side of the resin base material has a skin film containing a metal foil. It is characterized by being integrally fixed.

[0010]

EFFECT OF THE INVENTION According to such a method for producing a resinous resin outer plate for a vehicle, a resin material having an outer shell structure of a skin layer having a foamed inside and a dense surface layer is mainly used, and therefore, it is simple. The strength is higher than that of plate material, it is possible to reduce the weight while maintaining a predetermined rigidity, and it is not necessary to provide a large number of reinforcing parts as in blow molding products, so the surface appearance due to the reinforcing parts Of deterioration is prevented. Further, since the skin film is fixed on the surface of the resin material, a desired appearance regarding gloss and color can be easily given, and the skin film is preformed by a molding die for molding the resin material. Therefore, even if it has a metal foil, it can be preformed satisfactorily, and since it is fixed to the surface at the same time as the molding of the resin material, the outer shell made of resin for the vehicle having the outer shell structure is simply and inexpensively Can be manufactured. Further, if the skin film can be peeled off relatively easily, the processing at the time of recycling becomes easy.

In the second invention, since the laminated skin film having the metal foil is used, the appearance similar to that of the conventional metal hood can be easily obtained, and the electromagnetic wave is shielded so that the electronic components in the motor room are protected. The influence on the product etc. is prevented. Further, since it is not necessary to provide a reinforcing portion, it is possible to make the molding surfaces of the front surface side molding die and the back surface side molding die flat and substantially the same shape. By sandwiching and pressing the skin film between them, the skin film can be reliably preformed with high accuracy even when a relatively thick metal foil is used.

In the third aspect of the invention, the skin film is brought into close contact with the molding surface of the back side molding die by vacuum suction for preforming, and is pressed against the molding surface of the front side molding die in the subsequent compression molding step or expansion molding step. Since it is formed into the final shape, there is no risk that suction marks due to vacuum suction will remain on the surface of the skin film and impair the appearance.

In the fourth invention, polypropylene is used as the resin material and glass fiber is used as the reinforcing fiber, while the volume of the resin material including the skin layer is 1.3 to 3 times that in the expansion molding step. Thus, the weight can be reduced while maintaining a predetermined rigidity.

In the resinous outer plate for a vehicle of the fifth invention, the resinous base material is made of a resin material mixed with reinforcing fibers, and the resinous base material has a foamed inside and a surface layer portion. Has a dense outer shell structure, the strength is higher than that of a simple resin plate material, and the weight can be reduced while maintaining a predetermined rigidity. In addition, since the skin film containing the metal foil is integrally fixed to the vehicle surface side of the resin base material, it is easy to obtain the same appearance (gloss and color) as the conventional metal hood. Electromagnetic waves are shielded.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is preferably applied to a resin hood that covers a prime mover compartment, but can also be applied to a resin outer plate for other vehicles such as a lid member for a trunk room.

Polypropylene is preferably used as the resin material, and long-fiber glass fiber having a length of about 5 to 15 mm and a thickness of about 5 to 20 μm is preferably used as the reinforcing fiber. In the range in which strength and rigidity required as a plate can be obtained, for example, JP-A-10-305462.
Various thermoplastic resins and reinforcing fibers described in Japanese Patent Laid-Open Publications and the like can be adopted.

The skin film is preferably a laminated structure having a metal foil, but may be a film made of a resin material or the like without a metal foil, or a single metal thin film. As the metal foil, for example, chromium, aluminum, stainless steel, etc. are preferably used, and the thickness is appropriately within the range of about 1 to 10 μm. Further, a color layer containing a predetermined pigment may be provided on the outer side of the metal foil, and a clear layer may be provided on the outer side of the color layer, that is, the outermost surface to give gloss or light resistance. For example, urethane resin or melamine resin is preferably used for the color layer, and urethane resin or acrylic resin is preferably used for the clear layer.

The above-mentioned skin film is preformed by being brought into close contact with the forming surface of the back side forming die by vacuum suction as in the third invention, for example, but is made in close contact with the forming surface of the front side forming die to be preformed. You can also It is also possible to perform preforming by using the drawing of the second invention and vacuum suction together.

An injection device is preferably used for supplying the molten resin material. For example, the molten resin material may be flowed down on the molding surface of the lower mold to be supplied, and then the upper mold may be lowered to perform compression molding. Various modes can be adopted. Further, the skin film is integrally fixed as the molten resin material is cured, but the back surface of the skin film may be provided with irregularities or an adhesive may be applied, if necessary.

In the second invention and the third invention, the thickness dimension of the vehicle resin outer plate is substantially constant, and the molding surfaces of the front surface side molding die and the back surface side molding die have substantially the same shape. The fifth aspect of the invention can be applied to a vehicle-use resin outer panel having different thickness dimensions and different front and back shapes.

The resinous outer panel for a vehicle of the fifth invention is preferably manufactured by the manufacturing method of the first to fourth inventions, but may be manufactured by another manufacturing method such as molding the skin film separately. Is also possible.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a diagram showing a vehicle resin hood 10 manufactured according to the method of the present invention, in which a skin film 14 is integrally fixed to the surface, that is, the upper surface side of a flat plate-shaped resin base material 12 having a substantially constant thickness. (A) is a plan view,
(b) is a sectional view and (c) is an enlarged sectional view of the skin film 14. The resin base material 12 has a length of 5 to 5 as a reinforcing fiber.
It was made of polypropylene mixed with long glass fibers having a thickness of about 15 mm and a thickness of about 5 to 20 μm, and the inside 12a was in a foamed state (porous) and the surface layer 12b was a dense skin layer. It has an outer shell structure. As is apparent from FIG. 1 (c), the skin film 14 includes a thermoplastic resin base layer 20 fixed to the resin base material 12, and a metal foil integrally fixed onto the base layer 20. 22 and a color layer 24 integrally fixed to the metal foil 22 and a clear layer 26 integrally fixed to the color layer 24 to form a laminated structure. For example, chromium, aluminum, stainless steel or the like having a thickness of about 1 to 10 μm is used as 22. The base layer 20 is made of, for example, an olefin resin, the color layer 24 is made of, for example, urethane resin or melamine resin, and the clear layer is made of, for example, urethane resin or acrylic resin. The color layer 24 may be omitted and the clear layer 26 may be provided directly on the metal foil 22. The vehicle resin hood 10 is for covering the upper part of the prime mover chamber in front of the vehicle, and the lower end portion in FIG. 1 (a), that is, the rear side portion of the vehicle is attached to the vehicle body via a hinge or the like. It is attached so that it can be opened and closed.

Such a vehicular resin hood 10 is preferably manufactured using the press molding apparatus 30 shown in FIG. The press molding apparatus 30 includes a lower die 32 and the lower die 32.
And a molding surface 32f of the lower mold 32 that is vacuum-sucked on the upper film 34 and the upper film 34 that are vertically movable above the lower mold 32.
A vacuum suction device 36 that closely adheres to the mold, an injection device 38 that injects and supplies a molten resin material into the cavity formed by the lower mold 32 and the upper mold 34, and injects gas such as air into the molten resin material. The gas injection device 40 is provided. The lower die 32 has a substantially flat molding surface 32f having the same shape as the lower surface of the intended vehicle resin hood 10, that is, the surface on the side of the prime mover chamber, and the molding surface 32.
In f, a large number of suction ports for sucking air by the vacuum suction device 36, an injection port for injecting the molten resin material by the injection device 38, a gas injection port for supplying gas by the gas injection device 40, and the like. It is provided. Also,
The upper mold 34 is provided with a substantially flat molding surface 34f having the same shape as the upper surface, that is, the outer surface of the intended vehicle hood 10 for a vehicle, and is moved up and down by a vertical drive device such as a hydraulic or mechanical type. As a result, the lower mold 32 can be moved toward and away from the lower mold 32. The lower die 32 corresponds to the back side molding die, and the upper die 34 corresponds to the front side molding die.

First, as shown in FIG. 2, with the upper mold 34 separated upward, the deformable preheated skin film 14 is set on the molding surface 32f of the lower mold 32, and the upper mold 34 is lowered. And vacuum drawing by the vacuum suction device 36, the skin film 14 is pinched between the lower mold 32 and the upper mold 34 as shown in FIG. The surface 32f is suction-adhered and held until the skin film 14 is cooled to a predetermined temperature. The thickness of the vehicle resin hood 10 of this embodiment is substantially constant, and the molding surface 32f of the lower mold 32 and the molding surface 3 of the upper mold 34 are formed.
4f are substantially the same, and the skin film 14 may be preformed by bringing it into close contact with the molding surface 32f of the lower mold 32.
Further, the metal foil 22 is relatively thick (the deformation resistance is large) because the metal foil 22 is pressed and formed between the lower mold 32 and the upper mold 34 by drawing.
Even in this case, the skin film 14 is surely molded. Of FIG.
(a) is a preforming process.

Next, as shown in FIG. 3B, the upper mold 34
Is raised by a predetermined dimension, and the raw material of the resin base material 12, that is, the glass fiber is substantially uniformly dispersed by the injection device 38.
2 is injected and filled between the lower mold 32 and the skin film 14, and is kept in a predetermined compressed state in a cavity smaller than the target size. As a result, the surface layer portion of the molten resin 42, that is, the portion close to the molding surfaces 32f and 34f is cooled first to form a slightly hardened skin layer, while the skin film 14 is pressed against the molding surface 34f of the upper mold 34. It is molded into a desired shape with high accuracy and is integrally fixed to the skin layer. Since the back surface of the skin film 14 is composed of the base layer 20 of thermoplastic resin, the molten resin 42
The skin film 14 is integrally fixed with the cooling and curing of the above, but the back surface of the base layer 20 may be provided with irregularities as necessary. FIG. 3B shows the compression molding process.

After that, before the molten resin 42 inside the skin layer is cooled and hardened, the upper mold 34 is raised to a position having a target dimension as shown in FIG.
By injecting gas into the molten resin 42 by the gas injecting device 40, the molten resin 42 is expanded into a foamed state by the action of the glass fiber springback phenomenon and the gas pressure. As a result, as shown in FIG. 1, the skin film 1 is formed on the surface of the resin base material 12 having an outer shell structure in which the inside 12a is in a foamed state and the surface layer 12b is a dense skin layer.
The vehicle resin hood 10 to which 4 is integrally fixed is obtained. The expansion rate at this time, that is, the ratio of the volume of the resin base material 12 after expansion molding to the volume of the molten resin 42 shown in FIG. 3B, in other words, the increase rate of the vertical thickness is 1.
The position of the upper mold 34 in the compression molding step of FIG. 3 (b) is set so as to fall within the range of 3 to 3 times. Of FIG.
(c) is an expansion molding process.

In such a vehicle resin hood 10 of this embodiment, the resin base 12 is made of polypropylene mixed with glass fiber, and the inside 1
Since 2a has a foamed state and the surface layer 12b has an outer shell structure of a dense skin layer, the strength is higher than that of a simple resin plate material, and it is possible to reduce the weight while maintaining a predetermined rigidity.

In particular, in this embodiment, polypropylene is used as the resin material and glass fiber is used as the reinforcing fiber, while the volume of the resin base material 12 is 1.3 relative to the molten resin 42 in the expansion molding process. Since it is expanded so as to be three times as large, it is possible to surely reduce the weight while maintaining a predetermined rigidity.

Further, since the skin film 14 including the metal foil 22 is integrally fixed to the surface side of the resin base material 12, the same appearance (gloss, color, etc.) as a conventional metal hood is obtained. In addition to being easily obtained, electromagnetic waves are shielded and the influence on electronic products in the motor room is prevented. If the skin film 14 can be peeled off relatively easily, the process at the time of recycling becomes easy.

The skin film 14 is a resin base material 1.
2 is molded in advance by a lower mold 32 and an upper mold 34, and is integrally fixed to the surface of the resin base material 12 simultaneously with the molding of the resin base material 12, while the resin base material 12 is compressed and expanded. Since the outer shell structure having the skin layer is formed in the step, it is possible to easily and inexpensively manufacture the vehicle resin hood 10 having the outer shell structure to which the skin film 12 is fixed.

Further, since it is not necessary to provide the reinforcing portion unlike the blow-molded product, deterioration of the surface appearance due to the reinforcing portion is prevented, while the molding surfaces 32f and 34f of the lower mold 32 and the upper mold 34 are It is possible to have a flat and substantially the same shape, and the skin film 14 has a lower mold 32 and an upper mold 34 for them.
Since it is sandwiched between and to be formed by drawing, the skin film 14 can be reliably preformed with high accuracy even when the metal film 22 having a relatively large thickness is provided.

Further, by vacuum suction, the molding surface 3 of the lower mold 32
The skin film 14 is brought into close contact with 2f for preforming, and the molding surface 3 of the upper mold 34 is subjected to the subsequent compression molding process or expansion molding process.
Since it is pressed into 4f and molded into the final shape, there is no fear that suction marks due to vacuum suction will remain on the surface of the skin film 14 and spoil the appearance.

The embodiment of the present invention has been described in detail with reference to the drawings, but this is merely an embodiment,
The present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a view showing an example of a vehicle resin hood manufactured according to the method of the present invention, (a) is a plan view, (b) is a sectional view,
(c) is a cross-sectional view of the skin film.

FIG. 2 is a schematic configuration diagram illustrating a press molding apparatus that can manufacture the vehicle resin hood of FIG.

FIG. 3 is a diagram illustrating a manufacturing process when a vehicle resin hood is manufactured using the press molding apparatus of FIG.

[Explanation of symbols]

10: Resin hood for vehicle (outer plate) 12: Resin base material 12a: Inside 12b: Surface layer portion (skin layer) 14: Skin film
20: Base layer 22: Metal layer 32: Lower mold (backside mold) 3
4: Upper mold (front surface molding mold) 42: Molten resin

Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // B29K 23:00 B29K 105: 04 105: 04 B29L 31:30 B29L 31:30 B62D 25/10 D (72) Invention Author Yoshinori Suzuki 4-50, Hosoya-cho, Toyota-shi, Aichi Toyota Iron Works Co., Ltd. (72) Inventor So Sato 1 Toyota-cho, Toyota-shi, Aichi F-term inside Toyota Motor Corporation (reference) 3D004 AA01 AA03 BA02 CA05 4F206 AA11 AB25 AD04 AD16 AG03 AG20 AH18 JA04 JA07 JB13 JB30 JF05 JM05 JN27

Claims (5)

[Claims] 1. A method of manufacturing a resin outer panel for a vehicle using a pair of a front surface side molding die and a rear surface side molding die which are spaced apart from each other, wherein the front surface side molding die and the back surface side molding die are provided. Between the back surface side molding die and the skin film, a pre-forming step of disposing a skin film between the two, and deforming the skin film along one molding surface, and a molten resin material containing reinforcing fibers. And a predetermined compression state in a cavity smaller than the target dimension formed between the back side molding die and the front side molding die, thereby slightly curing the surface layer portion of the resin material. A compression molding step of fixing the skin film to the skin layer at the same time as forming the skin layer, and the front side molding die and the back side molding before the molten resin material inside the skin layer is cooled and cured. By separating the molds and injecting a gas into the molten resin material, the molten resin material is expanded into a foamed state by the action of the springback phenomenon of the reinforcing fibers and the gas pressure, and expansion to a target size is achieved. A method of manufacturing a resin outer panel for a vehicle, comprising: 2. The skin film has a laminated structure having a resin base layer and a metal foil laminated on the surface side of the base layer, and the thickness of the resin outer panel for a vehicle. The height dimension is substantially constant, the molding surfaces of the front surface side molding die and the back surface side molding die have substantially the same shape, and in the preliminary molding step, the back surface side molding die and the front surface side molding die have the same shape. The method for producing a resin outer panel for a vehicle according to claim 1, wherein the skin film is pressed and drawn. 3. The thickness dimension of the vehicle resin outer plate is substantially constant, the molding surfaces of the front surface side molding die and the back surface side molding die have substantially the same shape, and in the preliminary molding step, vacuum suction is performed. 3. The method for producing a resin outer panel for a vehicle according to claim 1, wherein the skin film is brought into close contact with the molding surface of the back side molding die to perform pre-molding. 4. The resin material is polypropylene, the reinforcing fiber is glass fiber, and the volume of the resin material portion including the skin layer is 1.
It expands so that it may become 3 to 3 times, The manufacturing method of the resin outer panel for vehicles of any one of Claims 1-3 characterized by the above-mentioned. 5. A vehicular resin outer panel mainly composed of a resin base material, wherein the resin base material is composed of a resin material mixed with reinforcing fibers, and While the inside has a foamed state and the surface layer has a dense skin layer outer shell structure, a skin film including a metal foil is integrally fixed to the vehicle surface side of the resin base material. A characteristic resin outer panel for vehicles.