JP2521035Y2 - Panel material for automobile outer panels - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a panel member for an automobile outer panel integrally formed by blow molding a skin and a stiffener which face each other with a synthetic resin, and particularly to a relatively large horizontal panel such as a bonnet, a trunk or a roof. The present invention relates to a panel member for an automobile outer panel, which is suitable for use as a vehicle.

[0002]

2. Description of the Related Art Conventionally, injection molding of a thermoplastic resin has been put into practical use as a panel member for an automobile outer panel made of a synthetic resin. However, since such a panel member has insufficient rigidity, a vertical member such as a fender is required. It is only used for panels.

Therefore, in order to form a relatively large horizontal panel such as a bonnet, a trunk or a roof, which requires sufficient rigidity, from a synthetic resin, the skin located outside the vehicle body and the stiffener located inside are made of FRP. It is necessary to separately form and bond them, or to set a stiffener formed from a stampable sheet in a mold and then injection-mold a skin with a thermoplastic resin.

[0004]

However, each of the above methods requires two molding steps, resulting in a long cycle time and problems in mass productivity and cost.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an outer panel panel for an automobile which has sufficient rigidity and can be manufactured by blow molding in a short time and at low cost. .

[0006]

In order to achieve the above object, the present invention provides a panel member for an automobile outer panel, which is formed by integrally blow-molding a skin and a stiffener, which face each other, with a synthetic resin. The first feature is that a rib forming a closed loop is integrally projected from the stiffener toward the skin, and the tip of the rib is fixed to the back surface of the skin.

In addition to the first feature described above, the present invention provides
A second feature is that the rib is provided with a notch for allowing a blow molding gas to flow therethrough.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an apparatus for blow-molding an automobile bonnet. The mold 1 is composed of a pair of mold halves 2 and 3 which can be opened and closed, and one mold half. The body 2 forms a skin on the front wall side of the bonnet, and the other mold half 3 forms a stiffener on the back wall side. The cavity surface of the mold half 2 is formed into a smooth curved surface corresponding to the surface of the skin, while the cavity surface of the mold half 3 is formed with ribs and dimples on the stiffener.
Book protrusions 3a to 3e and a plurality of protrusions 3h are provided in a protruding manner.
The ridges 3a, 3b, 3c, 3e are provided so as to form a substantially rectangular closed loop, and four notches 3 are provided at the corners thereof.
i is provided. Similarly, the ridges 3a, 3d, 3c, 3e are arranged so as to form a substantially rectangular closed loop, and four notches 3i are provided at the corners thereof.

The nozzle 5 of the parison extruder 4 has a flat shape so that the width of the mold 3 in the opening / closing direction is narrow and the width in the direction orthogonal thereto is wide. Therefore, the parison P extruded from the nozzle 5 has a flat tubular shape, and the wide surface thereof is sandwiched between the mold halves 2 and 3.

A blow pin 6 for supplying air into the parison P sandwiched between the mold halves 2 and 3 is provided in the mold 1 so as to be movable back and forth.

In this blow molding machine, after the parison P made of thermoplastic resin is extruded from the nozzle 5 of the parison extruder 4 with both mold halves 2 and 3 open,
The mold halves 2 and 3 are clamped. As a result, the upper and lower ends of the bag-shaped parison P are pinched by the outer peripheral portion of the mold 1 to be closed, and the important part of the middle part of the parison P is a ridge protruding from the mold half 3. 3a to 3e and the tips of the protrusions 3h are pressed against each other to be in close contact with each other.

Subsequently, the blow pin 6 inserted in the mold 1
The tip of the is pierced into the edge of the parison, and high pressure air is supplied to the inside. As a result, the parison P made of a thermoplastic resin expanded by the internal pressure is formed in close contact with the cavity surfaces of both mold halves 2 and 3, and is pressed by the tips of the protrusions 3a to 3e and the protrusion 3h. In, the front and back of the parison P are melted together and joined to each other. During the blow molding process, the high pressure air supplied from the blow pin 6 can be evenly distributed inside the parison P through the notches 3i formed between the protrusions 3a to 3e.

The bonnet B blow-molded as described above is a hollow body having a skin 7 having a smooth curved surface on the outside of the vehicle body and a stiffener 8 for reinforcing the back surface of the skin 7, as shown in FIGS. 3 and 4. With structure. Skin 7
The stiffener 8 and the stiffener 8 are in close contact with each other over the entire length of the outer periphery, and the ribs 8a to 8e protruding from the stiffener 8 and the tips of the plurality of dimples 8h are integrally fused to the back surface of the skin 7 at the intermediate portion. Four ribs 8a, 8b, 8c,
The rib 8e and the four ribs 8a, 8d, 8c, and 8e substantially form a closed loop except for the notch 8i, which gives the bonnet B a great rigidity against bending and twisting. be able to. Further, the plurality of dimples 8h arranged between the ribs 8a to 8e can provide resistance to the load in the direction in which the skin 7 and the stiffener 8 are crushed.

FIG. 5 and FIG. 6 show a second embodiment of the present invention. In this embodiment, another rib 8f is parallel to the rib 8a.
In addition to the fact that the strength is improved by adding
It is characterized in that the end portions of e are connected by a rib 8g having a low height. A notch 8i is formed between the rib 8g having a low height and the back surface of the skin 7, and the rib 8g improves the strength, and the notch 8i allows the flow of high-pressure air for blow molding. I have to.

7 and 8 show a third embodiment of the present invention. In this embodiment, a skin 7 and a stiffener 8 are connected by two ribs 8a to 8d provided on the stiffener 8 so as to project vertically and horizontally. ing. Nine closed loops are formed by the four ribs 8a to 8d and the outer periphery of the bonnet B, and the insides of these closed loops are the heights of the ribs 8a to 8d so as to enable the flow of high-pressure air for blow molding. Are communicated with each other by a notch 8i formed by partially lowering the height.

FIG. 9 shows a fourth embodiment of the present invention.
In this embodiment, the protrusions 3a to 3e and the protrusion 3h of the iron mold half 3 are formed of aluminum in order to prevent the surface of the skin 7 from being depressed by a sink during blow molding. ing.

That is, when the bonnet B blow-molded inside the mold 1 is cooled and solidified, the fusion portion of the skin 7 and the stiffener 8 has a large wall thickness and the cooling is delayed as compared with other portions. A concave portion due to a sink mark is generated on the surface of the skin 7 corresponding to the fused portion. However, as in this embodiment, the protrusions 3a to 3e and the protrusion 3h corresponding to the fusion-bonded portion are formed.
Is formed of aluminum having a higher thermal conductivity than iron, the fused portion can be cooled and solidified at an early stage to prevent the occurrence of sink marks.

FIG. 10 shows a fifth embodiment of the present invention. In this embodiment, the adhesive layer P ₁ is previously formed on the inner surface of the parison P.
Ribs of the stiffener 8 during blow molding
The tips of a to 8e and the dimples 8h and the back surface of the skin 7 are joined to each other by the adhesive layer P ₁ . According to this embodiment, since the thick portion due to fusion bonding is not formed, the problem of sink marks during cooling does not occur.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and does not deviate from the present invention described in the scope of claims for utility model registration.
It is possible to make various small design changes.

For example, in the examples, blow molding is carried out by air, but when air is used, the thermoplastic resin in the molten state, for example, the resin having an amide bond, is oxidized and the fusion between the skin and the stiffener is incomplete. Therefore, it is desirable to prevent the resin from oxidizing by using an inert gas such as helium or nitrogen instead of air. When the blow molding is performed using the inert gas as described above, the skin and the stiffener are reliably fused, so that the width of the fused portion can be narrowed. As a result, heat accumulation in the fusion-bonded portion becomes small, and sink marks are less likely to occur on the surface of the skin during cooling after blow molding,
The appearance can be improved. For the sake of perfection, it is desirable to purge the air inside the parison with an inert gas in advance.

Further, the panel member of the present invention is not limited to the bonnet but can be applied to other panel members such as a trunk and a roof. Further, the shape of the closed loop formed by the ribs is not limited to that of the embodiment, and any shape can be adopted.

[0023]

As described above, according to the first feature of the present invention, when the skin of the panel member and the stiffener are integrally blow-molded, the ribs that substantially form the closed loop are directed from the stiffener to the skin. Since the ribs are projectingly provided and the tips of the ribs are fixed to the back surface of the skin, it is possible to manufacture a highly rigid panel member in which the skin and the stiffener are firmly integrated with each other in a short time and at low cost. Also, when a car runs at high speed, negative pressure is generated on the skin side of the panel member due to aerodynamic force, but since the skin is connected to the stiffener through the ribs, the skin is prevented from being deformed by suction due to the negative pressure. it can.

Further, according to the second aspect of the present invention, since the rib is provided with a notch for allowing a blow molding gas to flow therethrough, the gas can be evenly distributed inside the parison for precise blow molding. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is an overall front view of a blow molding device (cross-sectional view taken along line 1-1 of FIG. 2).

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a partial sectional view of a bonnet according to the first embodiment.

FIG. 4 is a sectional view taken along line 4-4 of FIG.

FIG. 5 is a partial sectional view of a bonnet according to the second embodiment.

6 is a sectional view taken along line 6-6 of FIG.

FIG. 7 is a partial sectional view of a bonnet according to a third embodiment.

8 is a sectional view taken along line 8-8 of FIG.

FIG. 9 is a partial sectional view of a mold and a bonnet according to a fourth embodiment.

FIG. 10 is a partial sectional view of a bonnet according to a fifth embodiment.

[Explanation of symbols]

 7 ... Skin 8 ... Stiffener 8a-8g ... Rib 8i ... Notch

Claims (2)

(57) [Scope of utility model registration request] 1. A panel member for an automobile outer panel, which is obtained by integrally blow-molding a skin (7) and a stiffener (8), which face each other, with a synthetic resin, wherein the ribs (8a-8g) substantially form a closed loop. ) Is integrally projected from the stiffener (8) toward the skin (7), and the ribs (8a-8)
A panel member for an automobile outer panel, characterized in that the tip of (g) is fixed to the back surface of the skin (7). 2. The panel member for an automobile outer panel according to claim 1, wherein the ribs (8a to 8g) are provided with notches (8i) for allowing a blow molding gas to flow therethrough.