JP3623906B2 - Manufacturing method for vehicle interior parts - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a vehicle interior product having a structure in which a soft foam layer such as an instrument panel (hereinafter referred to as instrument panel) or a door trim is laminated in a sandwich shape, and more specifically, has a sound absorbing material layer on the back side. The present invention relates to a method for manufacturing a vehicle interior product.
[0002]
[Prior art]
As shown in FIG. 5, the instrument panel of an automobile includes a hard plate-like core member 300 made of glass fiber reinforced resin, a skin layer 301 made of polyvinyl chloride or the like, a skin layer 301 and a core member 300. And a foam layer 302 such as polyurethane formed therebetween. The core material 300 provides rigidity, and the foam layer 302 and the skin layer 301 provide good tactile sensation and appearance. In recent years, a sound absorbing material layer 303 such as felt or slab urethane is joined to the back surface of the core member 300, and the sound absorbing material layer 303 can prevent noise from an engine room or the like from entering the vehicle interior. Has been done.
[0003]
That is, by providing such a porous and soft sound-absorbing material layer 303, sound waves that reach the sound-absorbing material layer 303 are scattered, and sound energy is converted into thermal energy in a myriad of holes in the sound-absorbing material layer 303. As a result, the sound wave attenuates or disappears.
[0004]
In order to manufacture such an instrument panel, a core material 300 having a predetermined shape is first formed by injection molding or compression molding, and a skin body having a predetermined shape is formed by vacuum forming or the like. Next, the core material 300 and the skin body are placed in a mold, and foaming resin is injected between the core material 300 and the skin body to perform foam molding. The skin is pressed against the mold surface by the foaming pressure of the foamed resin, and a foam layer 302 having a predetermined shape joined integrally with the skin layer 301 and the core material 300 is formed.
[0005]
Then, after release from the mold, the excess skin is trimmed, and a sheet-like sound absorbing material layer 303 is joined to the back side of the core material 300 with a double-sided tape or an adhesive.
[0006]
[Problems to be solved by the invention]
However, in the method in which the sound absorbing material layer 303 is joined after the foam layer 302 is formed, the instrument panel is a large molded product and is heavy because the weight of the skin layer 301 and the foam layer 302 is added. There's a problem. For this reason, the positioning operation of the bonding position is not easy, and there is a problem that the positioning accuracy is not stable, and the number of steps for joining is large. Further, the skin layer 301 may be damaged during the joining operation, and the occurrence rate of defective products is high.
[0007]
Therefore, a method of forming the foam layer 302 by using the core material 300 in which the sound absorbing material layer 303 has been bonded in advance and placing it in a mold together with the outer skin and performing foam molding has been studied. According to this method, since the core material 300 that does not have the skin layer 301 and the foam layer 302 is handled in the process of joining the sound absorbing material layer 303, the burden on the operator can be reduced as compared with the method described above. , Positioning accuracy is also improved. Moreover, since the skin layer 301 is not damaged, the defect rate can be reduced.
[0008]
However, when an instrument panel with a sound absorbing material layer is manufactured by the above manufacturing method, it has been revealed that there is a problem that the dimensional accuracy is low. That is, when the foaming pressure of the foamed resin is increased in the foam molding process of the foam layer 302, the core material 300 and the sound absorbing material layer 303 are pressed toward the mold surface by the pressure. Then, since the sound absorbing material layer 303 is soft, it is compressed and deformed, and partial movement of the meat also occurs, so that the core material 300 is deformed.
[0009]
The present invention has been made in view of such circumstances, and an object of the present invention is to improve the dimensional accuracy in a method of foam-molding a foam layer by previously placing a base material having a sound-absorbing material layer in a mold. To do.
[0010]
[Means for Solving the Problems]
The feature of the method for manufacturing a vehicle interior product of the present invention that solves the above problem is that a plate-shaped core material made of a hard resin having a soft sound-absorbing material layer on the back surface side is disposed on one mold surface of the mold, A vehicle interior product in which a skin layer is disposed on the other mold surface of the molding die, and a foam layer is formed by injecting a foam resin between the skin body and the core material to form a foam layer bonded to the skin body and the core material. The core material partially has a core material convex portion that penetrates the sound absorbing material layer, and foam molding is performed with the tip of the core material convex portion in contact with one mold surface. is there.
[0011]
In the above manufacturing method, the core material convex portion is a rib formed on the surface of the core material, and the sound absorbing material layer preferably has a slit through which the rib penetrates.
[0012]
Another feature of the method for manufacturing a vehicle interior product according to the present invention is that a plate-like core material made of a hard resin having a soft sound-absorbing material layer on the back side is disposed on one mold surface of the mold, and molding is also performed. A vehicle interior product in which a skin layer is disposed on the other mold surface of a mold, and a foam layer is formed by injecting a foam resin between the skin body and the core material to form a foam layer bonded to the skin body and the core material. In the manufacturing method, the sound-absorbing material layer partially includes a hard portion, and foam molding is performed in a state where the hard portion is in contact with one mold surface.
[0013]
In the above manufacturing method, the hard part is a thin part formed by partially compressing the sound absorbing material layer, and the thin part is sandwiched between the mold convex part and the core material formed on one mold surface. It is desirable to perform foam molding.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
In one manufacturing method of the present invention, the foam layer is foam-molded in a state where the tips of the core convex portions of the core material are in contact with the mold surface of the mold. Therefore, when the foaming pressure is applied to the core material, the core material convex portion is held in a state of being pressed toward the mold surface, so that the sound absorbing material layer is less likely to be deformed by compression and the movement of meat is less likely to occur. Since the core material is hardly deformed, a vehicle interior product with high dimensional accuracy can be reliably manufactured.
[0015]
In another production method of the present invention, the foam layer is foam-molded in a state where the hard portion of the sound absorbing material layer is in contact with the mold surface of the mold. Therefore, even if foaming pressure is applied to the sound absorbing material layer through the core material, the hard portion is hardly compressed and deformed, and the hard portion is held in a state of being pressed against the mold surface, so that movement of the sound absorbing material layer also occurs. Hateful. As a result, the core material is hardly deformed, and a vehicle interior product with high dimensional accuracy can be reliably manufactured.
[0016]
In the manufacturing method of the present invention, a sound absorbing material layer is first bonded to the core material. Examples of the core material include hard resin such as PP, PE, nylon, ABS, AS, or a mixture of these with a reinforcing material such as glass fiber, and a predetermined plate-shaped core by injection molding, compression molding, or the like. A material can be formed. As the sound absorbing material layer, felt formed from various fiber materials, or foamed materials such as foamed PP, foamed PE, and foamed urethane can be used.
[0017]
In order to join the sound absorbing material layer to the core material, a method of joining with an adhesive or a double-sided tape, a method of joining by heat welding, and the like are exemplified. And in the process of joining a sound-absorbing material layer to a core material, since the core material does not have an epidermis body and a foam layer, it is lighter by that amount, and the burden on the operator can be reduced. In addition, there is no risk of scratching the epidermis.
[0018]
In one manufacturing method of the present invention, the core material partially has a core material protrusion that penetrates the sound absorbing material layer. This core material convex part can be made into various shapes, such as a needle | hook, protrusion, and a rib. For example, if the core material convex portion has a needle shape, the core material convex portion can be penetrated into the sound absorbing material layer. Further, when the core material convex portion is a protrusion, a rib, or the like, it is desirable to form a through portion such as a hole, a slit, or a notch for allowing the core material convex portion to penetrate in the sound absorbing material layer. In the case of the latter, the positioning accuracy at the time of joining a core material and a sound-absorbing material layer improves by engagement with a core material convex part and a penetration part.
[0019]
Moreover, it is preferable that a core convex part is a rib and a penetration part is a slit. In this way, the total area of the penetrating portion with respect to the entire area of the sound absorbing material layer can be reduced while exhibiting an effect of preventing deformation of the core material due to the contact between the core convex portion and the mold surface, and sound absorption by the penetrating portion can be reduced. The decrease in the sound absorbing effect of the material layer can be minimized. Further, the positioning accuracy can be further increased, and the work of joining the sound absorbing material layer is easy. This slit may be in the shape of a long hole whose both ends are located in the sound absorbing material layer, or may be in the form of a notch whose one end is open at the end of the sound absorbing material layer.
[0020]
And in another manufacturing method of this invention, the sound-absorbing material layer has a hard part partially. This hard part can be formed by partially impregnating the sound absorbing material layer with resin, or by partially applying pressure and heating. Alternatively, the hard member may be partially embedded or attached to the sound absorbing material layer, but it is desirable that the entire hard portion in the thickness direction is hard. However, when a sound-absorbing material layer having a hard part is joined to the core material, the positioning accuracy may be lower than when the core material convex part and the through part are provided. Therefore, it is desirable to use in combination with the structure having the core convex portion and the penetrating portion described above.
[0021]
The hard part is preferably a thin part formed by partially compressing the sound absorbing material layer. In this way, by forming a mold convex portion corresponding to the shape of the thin portion on one mold surface of the molding die, the mold surface of the molding die is engaged with the mold convex portion and the thin portion. The positioning accuracy at the time of disposing is improved. In foam molding, it is possible to more reliably prevent the sound absorbing material layer from moving relative to the mold surface due to the engagement between the mold convex portion and the thin portion, and the dimensional accuracy of the resulting vehicle interior product Is further improved.
[0022]
The number and pitch of the core material protrusions or hard parts can be variously set according to the strength of the core material itself and the foaming pressure, but in order to prevent deterioration of the sound absorption characteristics, keep the number to the minimum necessary. It is desirable to set the pitch as wide as possible.
[0023]
The epidermis is formed into a predetermined shape by vacuum forming a sheet made of a soft material such as PVC or thermoplastic elastomer. Alternatively, a skin having a predetermined shape can be produced by powder slush molding.
[0024]
Next, the core material to which the sound-absorbing material layer is bonded is disposed on one mold surface of the mold, and the skin formed in a predetermined shape is disposed on the other mold surface of the mold. Then, a foamed resin is injected between the skin body and the core material, and a foam layer integrally joined with the skin body and the core material is formed by foam molding. At this time, foam molding is performed with one or both of the core material convex portion and the hard portion being in contact with one mold surface, so that deformation of the core material and the sound absorbing material layer is prevented as described above, and dimensional accuracy is improved. High vehicle interior parts are produced.
[0025]
As the foamed resin for forming the foam layer, various foamed resins such as foamed urethane, foamed PP, and foamed polystyrene can be used. The injection method is not particularly limited, such as a simple injection method, an injection method, and a powder arrangement method, and the expansion ratio can be variously set according to the purpose.
[0026]
【Example】
Hereinafter, the present invention will be described specifically by way of examples.
[0027]
(Example 1)
FIG. 1 is a sectional view of an instrument panel manufactured by the manufacturing method of this embodiment. This instrument panel is integrally coated on a surface of the foam layer 2 and a plate-like core material 1 made of glass fiber reinforced AS resin, a foam layer 2 made of polyurethane foam formed on the surface side of the core material 1. The outer skin 3 made of PVC and the sound absorbing material layer 4 made of foamed polyurethane formed on almost the entire back surface of the core material 1. A plurality of ribs 10 are formed on the back surface side of the core material 1, and the tip surfaces thereof are exposed from the surface of the sound absorbing material layer 4.
[0028]
In manufacturing this instrument panel, first, as shown in FIG. 2, a core material 1 having ribs 10 was formed from glass fiber reinforced AS resin by injection molding. On the other hand, as shown in FIG. 2, a sound absorbing material 4 ′ having a plurality of slits 40 was formed from foamed urethane by foam molding. The thickness of the sound absorbing material 4 ′ is the same as the height of the rib 10, and the size of the slit 40 is almost the same as the dimension of the rib 10.
[0029]
Then, as shown in FIG. 2, the ribs 10 are respectively inserted into the corresponding slits 40, the sound absorbing material 4 ′ is joined to the core material 1 using a double-sided tape (not shown), and the sound absorbing material layer 4 is formed on the surface of the core material 1. Formed. At this time, the rib 10 and the slit 40 could be easily and accurately positioned. In addition, since the foam layer and the skin body are not formed on the core material 1, the core material 1 is lighter by that amount, and there is no fear of damaging the skin body. Therefore, the burden on the operator can be reduced and the number of man-hours can be reduced.
[0030]
On the other hand, a sheet material made of PVC was cut into a predetermined size and shaped into a predetermined shape by vacuum forming to form a skin body 3.
[0031]
Next, as shown in FIG. 3, the core material 1 having the sound absorbing material layer 4 is arranged so that the sound absorbing material layer 4 extends along one mold surface 50 of the pair of molds 5, and the skin 3 is placed on the other mold surface. The pair of molds 5 was closed by being arranged along the line 51. At this time, the tip surfaces of the plurality of ribs 10 that are exposed through the slits 40 of the sound absorbing material layer 4 are in contact with the mold surface 50.
[0032]
In that state, a predetermined amount of foamed urethane resin (not shown) was injected into the cavity 13 formed between the core material 1 and the skin 3 and foamed to form the foam layer 2. At this time, the core material 1 is pressed in the direction close to the mold surface 50 by the foaming pressure. However, since the plurality of ribs 10 are in contact with and supported by the mold surface 50, deformation of the core material 1 is prevented. Further, since the deformation of the core material 1 is prevented, the sound absorbing material layer 4 is not compressed, and the elastic reaction force due to the compression does not act on the core material 1.
[0033]
Therefore, the core material 1 is not deformed, and the instrument panel with the sound absorbing material layer can be manufactured with high dimensional accuracy according to the manufacturing method of this embodiment. Further, since the area of the end face of the rib 10 exposed to the slit 40 of the sound absorbing material layer 4 is sufficiently small, the sound absorbing action of the sound absorbing material layer 4 is sufficiently exerted, and the noise from the engine room enters the vehicle interior. Well can be prevented.
[0034]
(Example 2)
In this example, first, a felt made of PP fiber was prepared, and heat-pressed in a mold, and shaped into a predetermined shape to form a sound absorbing material 6 ′ shown in FIG. At this time, a part was strongly pressed and compressed to form a concave hard portion 60 to which the fibers were fixed. A plurality of hard portions 60 are formed in a circular shape with a diameter of 8 mm at a pitch of 50 mm, and each of them is a thin-walled concave portion that is thinner than other portions. And the flat surface located in the opposite side to the recessed part of this sound-absorbing material 6 'was joined by the double-sided tape and the flat core material 1 formed by injection molding separately. Since the foam layer and the skin body are not formed on the core material 1, the core material 1 is lighter by that amount, and there is no fear of damaging the skin body. Therefore, the burden on the operator is reduced and the number of man-hours can be reduced.
[0035]
On the other hand, a sheet material made of PVC was cut into a predetermined size and shaped into a predetermined shape by vacuum forming to form a skin 3 similar to that in Example 1.
[0036]
Next, as shown in FIG. 4, the core material 1 having the sound absorbing material layer 6 is arranged so that the sound absorbing material layer 4 extends along one mold surface 50 of the pair of molds 5, and the skin 3 is placed on the other mold surface. The pair of molds 5 was closed by being arranged along the line 51. One mold surface 50 is formed with a concave shape of the hard portion 60 and a plurality of mold convex portions 52 corresponding to the positions thereof, and the mold convex portion 52 engages with the concave hard portion 60 to form the hard portion. 60 is held together with the core material 1. Therefore, the positioning of the core material 1 having the sound absorbing material layer 6 can be accurately and easily performed by the engagement between the mold convex portion 52 and the hard portion 60.
[0037]
In that state, a predetermined amount of foamed urethane resin (not shown) was injected into the cavity 13 formed between the core material 1 and the skin 3 and foamed to form the foam layer 2. At this time, the core material 1 and the sound-absorbing material layer 6 are pressed in the direction close to the mold surface 50 by the foaming pressure, but the plurality of hard portions 60 abut against the mold convex portions 52, and the hard portions 60 are hardly compressed. Therefore, deformation of the core material 1 is prevented. Further, since deformation of the core material 1 is prevented, portions other than the hard portion 60 of the sound absorbing material layer 6 are not compressed, and elastic reaction force due to compression does not act on the core material 1.
[0038]
Therefore, the core material 1 is not deformed, and the instrument panel with the sound absorbing material layer can be manufactured with high dimensional accuracy according to the manufacturing method of this embodiment. Further, since the area of the hard portion 60 of the sound absorbing material layer 6 is sufficiently small, the sound absorbing action of the sound absorbing material layer 6 is sufficiently exerted, and the noise from the engine room can be well prevented from entering the vehicle compartment.
[0039]
In addition, the hard part 60 is further formed in the sound-absorbing material layer 4 having the slit 40 by combining the first and second embodiments, the rib 10 is inserted through the slit 40, and the mold convex part 52 is engaged with the hard part 60. It is also preferable to combine them. In this way, the positioning accuracy when the sound absorbing material layer 4 and the core material 1 are joined is improved, and the core material 1 having the sound absorbing material layer 4 is disposed on one mold surface 50 of the mold 5. The positioning accuracy is improved. Therefore, an instrument panel with higher dimensional accuracy can be manufactured.
[0040]
【The invention's effect】
That is, according to the manufacturing method of the present invention, a vehicle interior product having extremely high dimensional accuracy can be manufactured easily and reliably, and the number of steps required for manufacturing can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an instrument panel manufactured in an embodiment of the present invention.
FIG. 2 is a perspective view showing a state before joining a core material and a sound absorbing material in one embodiment of the present invention.
FIG. 3 is a cross-sectional view of an essential part showing a configuration in a mold immediately before foam-molding a foam layer in one embodiment of the present invention.
FIG. 4 is a cross-sectional view of a main part showing a configuration in a mold immediately before foam-molding a foam layer in a second embodiment of the present invention.
FIG. 5 is a cross-sectional view of an instrument panel manufactured by a conventional manufacturing method.
[Explanation of symbols]
1: Core material 2: Foam layer 3: Skin body 4: Sound absorbing material layer 5: Mold 10: Rib (core material convex part)
40: Slit 60: Hard part 52: Mold convex part

Claims (4)

A plate-shaped core material made of a hard resin having a soft sound-absorbing material layer on the back side is disposed on one mold surface of the molding die, and a skin body is disposed on the other mold surface of the molding die. And a method of manufacturing a vehicle interior product that forms a foam layer bonded to the outer skin and the core material by injecting a foam resin between the core material and performing foam molding,
The core material has a core material convex portion partially penetrating the sound absorbing material layer, and the foam molding is performed in a state where the tip of the core material convex portion is in contact with one of the mold surfaces. Manufacturing method for vehicle interior parts. 2. The method for manufacturing a vehicle interior product according to claim 1, wherein the core convex portion is a rib formed on the surface of the core material, and the sound absorbing material layer has a slit through which the rib penetrates. A plate-shaped core material made of a hard resin having a soft sound-absorbing material layer on the back side is disposed on one mold surface of the molding die, and a skin body is disposed on the other mold surface of the molding die. And a method of manufacturing a vehicle interior product that forms a foam layer bonded to the outer skin and the core material by injecting a foam resin between the core material and performing foam molding,
The sound absorbing material layer has a hard part partially, and the foam molding is performed in a state where the hard part is in contact with one of the mold surfaces. The hard part is a thin part formed by partially compressing the sound absorbing material layer, and the thin part is sandwiched between the mold convex part formed on one of the mold surfaces and the core member. The method for manufacturing a vehicle interior product according to claim 3, wherein the foam molding is performed.

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