JP4028699B2 - Resin outer plate for vehicle and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin outer plate for a vehicle, and more particularly to a technique for reducing the weight while securing a predetermined rigidity and manufacturing the resin at a low cost.
[0002]
[Prior art]
2. Description of the Related Art As a hood that covers an upper portion of a prime mover portion disposed at a front portion of a vehicle so as to be openable and closable, a resin hood integrally formed of a resin material such as ABS or polystyrene is known. A hood (bonnet) described in Japanese Patent Application Laid-Open No. 10-129526 is an example, and has a hollow outer shell structure by blow molding, and can be reduced in weight while ensuring a predetermined rigidity.
[0003]
[Problems to be solved by the invention]
However, such a resin hood needs to be top-coated (painted) in order to improve the appearance, and expensive coating equipment is required, resulting in high manufacturing costs. In addition, when a hollow outer shell structure is formed by blow molding, it is necessary to provide a large number of reinforcing portions (connecting portions of front and back panels) in order to ensure a predetermined rigidity, and the surface appearance may be impaired.
[0004]
The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a resin hood for a vehicle that has an excellent appearance and is lightweight and inexpensive.
[0005]
[Means for Solving the Problems]
In order to achieve this object, the first invention is a method of manufacturing a resin outer plate for a vehicle using a pair of front surface side mold and back surface mold that are brought close to and away from each other. A pre-molding step in which a skin film is disposed between the front-side mold and the back-side mold, and the skin film is deformed along one molding surface; and (b) a molten resin containing reinforcing fibers. The material is supplied between the back-side mold and the skin film, and kept in a predetermined compressed state in a cavity smaller than a target dimension formed between the back-side mold and the front-side mold. A compression molding step of fixing the skin film to the skin layer at the same time as forming a slightly hardened skin layer on the surface portion of the molten resin material, and (c) a molten resin material inside the skin layer. Cooling / hardness Before the surface side mold and the back side mold are separated from each other and by injecting a gas into the molten resin material, the molten resin is subjected to the springback phenomenon of the reinforcing fiber and the action of gas pressure. inflating the material into the foamed state possess an expansion molding step for the purpose sizes, and, (d) the skin film, the thermoplastic resin base layer is secured to the skin layer, the base layer and form a laminated structure having a metal foil laminated on the surface side than, (e) in the preforming step, clamping the skin film between said surface side mold and the back side mold It is characterized by press forming .
[0006]
The second invention provides a method of manufacturing a vehicle resin exterior panel of the first invention, the thickness of the pre-Symbol vehicle resin exterior panel is substantially constant, shaping of the surface-side mold and the back-side mold plane is substantially characterized the same shape der Turkey.
[0007]
According to a third aspect of the present invention, in the method for manufacturing a resin outer plate for a vehicle according to the first or second invention, (a) the thickness dimension of the resin outer plate for a vehicle is substantially constant; The molding surface of the back-side mold is substantially the same shape, and (b) in the preliminary molding step, the skin film is brought into close contact with the molding surface of the back-side mold by vacuum suction, and the drawing and vacuum suction thereof And preforming together .
[0008]
According to a fourth aspect of the present invention, in the method for manufacturing a resin outer plate for a vehicle according to any one of the first to third aspects, the resin material is polypropylene, the reinforcing fiber is glass fiber, and in the expansion molding step, The resin material including the skin layer is expanded so that the volume thereof is 1.3 to 3 times.
[0009]
A fifth invention is a resin outer plate for a vehicle composed mainly of a resin base material, and (a) the resin base material is made of a resin material mixed with reinforcing fibers. In addition, while the inside is foamed and the surface layer portion has an outer shell structure of a dense skin layer, (b) the resin base material is fixed to the resin base material on the vehicle surface side It has a laminated structure having a base layer made of thermoplastic resin and a metal foil laminated on the surface side of the base layer , and the resin base material before molding the resin base material clamping pressurized by draw forming epidermal Fimuru between the back side mold and the surface-side molding mold for molding the, characterized in that it is integrally fixed.
[0010]
【The invention's effect】
According to such a method for manufacturing a resin outer plate for a vehicle, the resin layer is mainly composed of a resin material having an outer shell structure of a skin layer in which the inside is foamed and the surface layer portion is dense. It is possible to reduce the weight while maintaining a predetermined rigidity, and since it is not necessary to provide a large number of reinforcing parts as in the case of blow molded products, the deterioration of the surface appearance due to the reinforcing parts is prevented. The In addition, since the skin film is fixed to the surface of the resin material, it is possible to easily give a desired appearance with respect to gloss and color, and the skin film is molded in advance by a molding die for molding the resin material. Therefore, even if it has a metal foil, it can be preformed well, and is fixed to the surface simultaneously with the molding of the resin material. Can be manufactured. Furthermore, if the skin film can be peeled off relatively easily, processing during recycling becomes easy.
[0011]
In addition, the use of a laminated skin film with metal foil makes it possible to easily obtain the same appearance as a conventional metal hood and to shield electromagnetic waves from affecting the electronic products in the prime mover room. Is prevented. Further, by clamping pressure in draw forming a skin film between the front side mold and the back side mold, it can be preformed reliably high precision skin film even when using a relatively thick metal foil.
[0012]
In the third aspect of the invention, the skin film is brought into close contact with the molding surface of the back side mold by vacuum suction, preliminarily molded using a combination of drawing and vacuum suction, and then the front side mold in the subsequent compression molding process or expansion molding process. Therefore, there is no fear that the appearance of suction by vacuum suction remains on the surface of the skin film and the appearance is not impaired.
[0013]
In the fourth invention, polypropylene is used as the resin material and glass fiber is used as the reinforcing fiber. On the other hand, in the expansion molding process, the volume of the resin material including the skin layer is expanded to 1.3 to 3 times. Therefore, the weight can be reduced while maintaining a predetermined rigidity.
[0014]
In the resin outer plate for a vehicle according to the fifth aspect of the invention, the resin base material is composed of a resin material mixed with reinforcing fibers, and the resin base material is foamed inside and the surface layer portion is dense. Since the outer shell structure of the skin layer is formed, the strength is higher than that of a simple resin plate, and the weight can be reduced while maintaining a predetermined rigidity. Also, on the vehicle surface side of the resin base material, a skin film having a laminated structure having a base layer made of a thermoplastic resin and a metal foil laminated on the surface side of the base layer is integrated. Therefore, the appearance (gloss, color, etc.) similar to that of a conventional metal hood can be easily obtained, and electromagnetic waves are shielded.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is preferably applied to a resin hood that covers the prime mover chamber, but may also be applied to other vehicle resin outer plates such as a trunk room lid member.
[0016]
Polypropylene is preferably used as the resin material, and glass fiber of a long 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, but is necessary as a vehicle outer plate. Various thermoplastic resins and reinforcing fibers described in, for example, Japanese Patent Application Laid-Open No. 10-305462 can be used within a range in which sufficient strength and rigidity can be obtained.
[0017]
The gold Shokuhaku epidermal film, such as chromium, aluminum, stainless steel, etc. are preferably used, the thickness is appropriately within a range of about 1 to 10 [mu] m. In addition, a color layer containing a predetermined pigment may be provided on the outside of the metal foil, and a clear layer may be provided on the outside of the color layer, that is, on the outermost surface, to give gloss or to provide light resistance. For example, urethane resin or melamine resin is suitably used as the color layer, and for example, urethane resin or acrylic resin is suitably used as the clear layer.
[0018]
The skin film, for example, the third to preformed in combination draw forming and the vacuum as in the invention, but we brought into close contact with the molding surface of the rear mold is by vacuum suction in the third invention, the surface-side molding by close contact with the molding surface of the mold Ru can be preformed.
[0019]
An injection apparatus is preferably used for supplying the molten resin material. For example, after the molten resin material is flowed down and supplied onto the molding surface of the lower mold, the upper mold can be lowered to perform compression molding. Aspects can be employed. Further, the skin film is integrally fixed as the molten resin material is cured. However, if necessary, the back surface of the skin film may be provided with irregularities or an adhesive may be applied.
[0020]
In the second and third inventions, the thickness of the resin outer plate for a vehicle is substantially constant, and the molding surfaces of the front-side molding die and the back-side molding die are substantially the same, but the first invention and the fifth invention Can also be applied to a resin outer plate for a vehicle in which the thickness dimension is changed and the shapes of the front and back surfaces are different.
[0021]
The vehicle resin exterior panel of the fifth invention, Ru is preferably produced by the production method of the first invention to the fourth invention.
[0022]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a view showing a resin hood 10 for a vehicle manufactured according to the method of the present invention, and a skin film 14 is integrally fixed to the surface, that is, the upper surface side of a flat resin substrate 12 having a substantially constant thickness. (A) is a plan view, (b) is a cross-sectional view, and (c) is an enlarged cross-sectional view of the skin film 14. The resin base material 12 is made of polypropylene mixed with long glass fibers having a length of about 5 to 15 mm and a thickness of about 5 to 20 μm as reinforcing fibers, and the inside 12 a is in a foamed state. The outer shell 12b has a porous structure in which the surface layer 12b is a dense skin layer. As is apparent from FIG. 1 (c), the skin film 14 is made of a thermoplastic resin base layer 20 fixed to the resin base material 12, and a metal foil fixed integrally on the base layer 20. 22, a color layer 24 integrally fixed on the metal foil 22, and a clear layer 26 integrally fixed on the color layer 24. As 22, for example, chromium, aluminum, stainless steel or the like having a thickness in the range of about 1 to 10 μm is used. The base layer 20 is made of, for example, 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. The lower end 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. Used attached to open and close.
[0023]
Such a resin hood 10 for a vehicle is suitably manufactured using a press molding apparatus 30 shown in FIG. The press molding apparatus 30 vacuum-sucks the lower mold 32, the upper mold 34 disposed above the lower mold 32 so as to be movable up and down, and the skin film 14 so as to adhere to the molding surface 32f of the lower mold 32. A vacuum suction device 36, an injection device 38 for injecting and supplying a molten resin material into a cavity formed by the lower mold 32 and the upper mold 34, and gas injection for injecting a gas such as air into the molten resin material Device 40. The lower mold 32 is provided with 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 prime mover chamber side. A large number of suction ports for sucking air, an injection port for injecting a molten resin material by the injection device 38, a gas injection port for supplying gas by the gas injection device 40, and the like are provided. The upper die 34 is provided with a substantially flat molding surface 34f having the same shape as the upper surface, ie, the outer surface, of the target vehicle resin hood 10, and is moved up and down by a hydraulic or mechanical vertical drive device. Thus, the lower mold 32 can be moved closer to and away from the lower mold 32. The lower mold 32 corresponds to the back side mold, and the upper mold 34 corresponds to the front side mold.
[0024]
Then, first, with the upper die 34 being spaced upward as shown in FIG. 2, the skin film 14 preheated so as to be deformable is set on the molding surface 32f of the lower die 32, and the upper die 34 is lowered and vacuumed. As shown in FIG. 3 (a), the skin film 14 is pressed between the lower mold 32 and the upper mold 34 to be drawn and formed on the molding surface 32f of the lower mold 32 by evacuating the suction device 36. Suction and close contact are maintained until the skin film 14 is lowered to a predetermined temperature. The thickness of the resin hood 10 for a vehicle of this embodiment is substantially constant, the molding surface 32f of the lower mold 32 and the molding surface 34f of the upper mold 34 are substantially the same, and the skin film 14 is molded to the molding surface 32f of the lower mold 32. It may be pre-molded by being in close contact with. Further, since the lower mold 32 and the upper mold 34 are nipped and drawn, the skin film 14 is reliably formed even when the metal foil 22 is relatively thick (large deformation resistance). FIG. 3A shows a preforming process.
[0025]
Next, as shown in FIG. 3 (b), the upper die 34 is raised by a predetermined dimension, and the raw material of the resin base material 12, that is, the glass fiber is dispersed substantially uniformly by the injection device 38. The molten resin 42 is injected and filled between the lower mold 32 and the skin film 14 and is held in a predetermined compressed state in a cavity smaller than the target dimension. As a result, the surface layer portion of the molten resin 42, that is, the portions close to the molding surfaces 32 f and 34 f are cooled first to form a slightly cured skin layer, while the skin film 14 is pressed against the molding surface 34 f of the upper die 34. It is molded to 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 the thermoplastic resin, the skin film 14 is integrally fixed as the molten resin 42 is cooled and cured. The surface may be provided with unevenness. FIG. 3B shows a compression molding process.
[0026]
Thereafter, before the molten resin 42 inside the skin layer cools and hardens, the upper mold 34 is raised to a target size as shown in FIG. By injecting gas into 42, the molten resin 42 is expanded into a foamed state by the action of the glass fiber springback phenomenon and gas pressure. As a result, as shown in FIG. 1, the skin film 14 is integrally fixed to the surface of the resin-made base 12 having an outer shell structure in which the inside 12a is in a foamed state and the surface layer portion 12b is a dense skin layer. A resin hood 10 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 rate of increase in the thickness in the vertical direction is 1.3-3. The position of the upper die 34 in the compression molding step of FIG. 3B is set so as to be within the double range. FIG. 3C shows an expansion molding process.
[0027]
In the vehicle resin hood 10 of this embodiment, the resin base material 12 is made of polypropylene mixed with glass fiber, and the inner layer 12a is foamed and the surface layer 12b is a dense skin layer. Therefore, the strength is higher than that of a simple resin plate, and the weight can be reduced while maintaining a predetermined rigidity.
[0028]
In particular, in this embodiment, polypropylene is used as the resin material, and glass fiber is used as the reinforcing fiber. On the other hand, in the expansion molding process, the volume of the resin base material 12 is 1.3 to 3 times that of the molten resin 42. Therefore, the weight can be reliably reduced while maintaining a predetermined rigidity.
[0029]
Further, since the skin film 14 including the metal foil 22 is integrally fixed to the surface side of the resin base material 12, an appearance (gloss, color, etc.) similar to that of a conventional metal hood can be easily obtained. In addition, the electromagnetic wave is shielded to prevent the influence on the electronic products in the prime mover room. If the skin film 14 can be peeled off relatively easily, processing during recycling becomes easy.
[0030]
The skin film 14 is molded in advance by the lower mold 32 and the upper mold 34 for molding the resin base material 12 and is integrally fixed to the surface at the same time as the resin base material 12 is molded. Since the base material 12 has an outer shell structure having a skin layer in the compression molding process and the expansion molding process, the outer shell resin resin hood 10 to which the skin film 12 is fixed is easily and inexpensively manufactured. Can do.
[0031]
Further, since it is not necessary to provide a reinforcing portion unlike a blow-molded product, the 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 substantially flat. The skin film 14 can be formed in the same shape, and the skin film 14 is pressed and drawn between the lower mold 32 and the upper mold 34, so that the skin film can be formed even when the metal foil 22 is relatively thick. 14 can be reliably preformed with high accuracy.
[0032]
Further, the outer skin film 14 is brought into close contact with the molding surface 32f of the lower mold 32 by vacuum suction and preformed, and then pressed to the molding surface 34f of the upper mold 34 in the subsequent compression molding process or expansion molding process to be molded into the final shape. Therefore, there is no possibility that the suction mark by vacuum suction remains on the surface of the skin film 14 to impair the appearance.
[0033]
As mentioned above, although the Example of this invention was described in detail based on drawing, this is an embodiment to the last, and this invention implements in the aspect which added the various change and improvement based on the knowledge of those skilled in the art. Can do.
[Brief description of the drawings]
FIG. 1 is a view showing an example of a resin hood for a vehicle manufactured according to the method of the present invention, wherein (a) is a plan view, (b) is a sectional view, and (c) is a sectional view of a skin film.
2 is a schematic configuration diagram illustrating a press molding apparatus that can manufacture the resin hood for a vehicle in FIG. 1; FIG.
3 is a diagram for explaining a manufacturing process when manufacturing a resin hood for a vehicle using the press molding apparatus of FIG. 2; FIG.
[Explanation of symbols]
10: Resin hood for vehicle (outer plate) 12: Substrate made of resin 12a: Internal 12b: Surface layer portion (skin layer) 14: Skin film 20: Base layer 22: Metal foil 32: Lower mold (back-side mold) 34: Upper mold (surface-side mold) 42: Molten resin

Claims (5)

A method of manufacturing a resin outer plate for a vehicle using a pair of front surface side mold and back surface side mold that are brought close to and away from each other,
Placing a skin film between the surface-side mold and the back-side mold, and a preforming step for deforming the skin film following one molding surface;
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. A compression molding step of fixing the skin film to the skin layer at the same time as forming a slightly cured skin layer on the surface layer portion of the resin material by maintaining a predetermined compression state in the cavity;
Before the molten resin material inside the skin layer cools and hardens, the front side mold and the back side mold are separated from each other, and gas is injected into the molten resin material, thereby An expansion molding process in which the molten resin material is expanded into a foamed state by the action of a fiber springback phenomenon and gas pressure to obtain a target dimension;
And
The skin film has a laminated structure having a base layer made of a thermoplastic resin fixed to the skin layer, and a metal foil laminated on the surface side of the base layer,
In the pre-molding step, the outer skin film is sandwiched between the back-side mold and the front-side mold to draw-mold. A method for producing a resin outer plate for a vehicle. The vehicle resin according to claim 1, wherein a thickness dimension of the vehicle resin outer plate is substantially constant, and molding surfaces of the front surface side mold and the back surface side mold are substantially the same. A method for manufacturing an outer plate. The thickness dimension of the resin outer plate for a vehicle is substantially constant, and the molding surfaces of the front side molding die and the back side molding die are substantially the same shape,
3. The preforming step, wherein the skin film is brought into close contact with a molding surface of the back-side molding die by vacuum suction, and preforming is performed by using the drawing and vacuum suction together. The manufacturing method of the resin-made outer plate | board for vehicles as described in any one of. The resin material is polypropylene, the reinforcing fiber is glass fiber, and in the expansion molding step, the resin material portion including the skin layer is expanded so that the volume is 1.3 to 3 times. The manufacturing method of the resin-made outer plate | board for vehicles of any one of Claims 1-3 to do. A resin outer plate for a vehicle composed mainly of a resin base material,
While the resin base material is made of a resin material mixed with reinforcing fibers, and the inside is in a foamed state and the surface layer portion has a dense outer skin structure,
On the vehicle surface side of the resin base material, a laminated structure having a thermoplastic resin base layer fixed to the resin base material and a metal foil laminated on the surface side of the base layer is formed. And a skin film that is drawn and pressed between a back-side mold and a front-side mold for molding the resin substrate before molding the resin substrate. A resin outer plate for a vehicle characterized by being integrally fixed.

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