JP2003095139A - Resin hood for vehicle and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the head part of a human body from getting a secondary damage by its re-collision to the vicinity of the hinge of a hood in an accident. SOLUTION: A buckling part 14 of outer shell columnar structure having an inner part 10a in foam state and a surface layer part 10b in dense state is integrally formed between a hood body 12 and a hinge connection part 16 to provide an excellent impact energy absorbing action by the buckling of the buckling part 14 so as to relieve an effect (impact) on the human body from the secondary collision to the vicinity of a hinge 22. Particularly, since the inside of the buckling part 14 is formed in foam state, a more excellent impact energy absorbing action than that of a simple hollow structure can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular resin hood, and more particularly to a technique for preventing a human body from re-colliding near the hinge of the hood and being secondarily damaged in the event of an accident. is there.

[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 thereof. The hood has a hollow outer shell structure by blow molding, and a hinge connecting member (nut) is provided at the rear end of the hood. Is insert-molded, and is openably and closably attached to the vehicle body via a hinge.

[0003]

However, in such a resin hood for vehicles, when the head of the human body or the like collides with the hinge of the hood again in the event of an accident, the hinge is generally made of metal and fixed to the vehicle body. Therefore, even if the hood itself is made of a resin material, there is a possibility of giving a large impact to the human body and causing secondary damage. When the resin material has a normal solid structure, the impact received by the hinge and the vehicle body acts on the human body through the resin material as it is, while even in the case of the hollow outer shell structure, it is attached to the vehicle body through the hinge. Since the amount of deformation of the resin material is small in this portion and the resin material is easily crushed in the plate thickness direction, a sufficient impact energy absorbing action cannot be obtained and a large impact is applied to the human body by the hinge or the like.

In a passenger car or the like having a hood protruding forward, when a pedestrian bounces in front of the vehicle, there is a high possibility that the head of the pedestrian may collide with the hinge of the hood again.
In terms of safety, it is strongly desired to mitigate the impact caused by collision near the hinge.

The present invention has been made in view of the above circumstances. The object of the present invention is to prevent a secondary damage such as the head of a human body colliding with the vicinity of the hinge of the hood again in the event of an accident. It is to suppress receiving.

[0006]

In order to achieve such an object, the first invention is (a) a resin hood main body that covers a front part of a vehicle, and (b) a hood main body that can be opened and closed in a vehicle body. To attach, a hinge connecting part in which a hinge connecting member is insert-molded on the back side of the rear end of the hood body,
In a vehicle resin hood having, (c) the hood body and the hinge connecting portion are made of a resin material mixed with reinforcing fibers, and between the hood body and the hinge connecting portion. Is characterized in that a buckling portion having an outer shell columnar structure in which the inside is foamed and the surface layer portion is dense is integrally provided.

According to a second aspect of the invention, (a) a resin hood main body that covers the front part of the vehicle and (b) the hood main body is attached to the vehicle body so that the hood main body can be opened and closed. A vehicle-made resin hood having a hinge connecting portion in which the hinge connecting member is insert-molded, (c) a method of manufacturing using a pair of front surface side molding die and back surface molding die, (d) While setting the hinge connecting member in a connecting portion forming recess provided in the back surface side molding die corresponding to the hinge connecting portion, a molten resin material containing reinforcing fibers is formed on the back surface side forming die. A compression molding step of curing the surface layer portion of the resin material including the hinge connection portion by maintaining a predetermined compression state in the cavity with the front surface side molding die, (e) of the back surface side molding die Of which, at least the connecting portion molding recess While the component is relatively separated from the surface side mold, gas is injected into the molten resin material before curing inside, and the molten resin material is foamed by the action of the springback of the reinforcing fiber and the gas pressure. Expansion molding step of forming a buckling portion of the outer shell columnar structure in which the inside is in a foamed state and the surface layer portion is dense between the hood body and the hinge connecting portion. To do.

According to a third aspect of the present invention, in the method of manufacturing a resin hood for a vehicle according to the second aspect, the expansion molding step relatively separates the front surface side mold and the back surface side mold from each other, and the hood main body. Also, it is characterized in that the inside has a foamed state and the surface layer has a dense outer shell structure.

A fourth aspect of the present invention is the method for producing a resin hood for a vehicle according to the second or third aspect of the invention, wherein: (a) the connecting portion forming recess of the back side forming die is formed on the front side forming die. In a nesting structure capable of being partially separated from each other, (b) in the expansion molding step, the nest is separated from the front surface side mold to form the buckling portion. And

[0010]

In the vehicle resin hood of the first aspect of the present invention, the buckling portion having the outer shell columnar structure in which the inside is foamed and the surface layer portion is dense is integrally provided between the hood body and the hinge connecting portion. Therefore, the buckling of the buckling portion provides an excellent effect of absorbing the collision energy, and the effect (impact) on the human body at the time of a secondary collision near the hinge is mitigated. In particular,
Since the inside of the buckling portion is in a foamed state, a more excellent collision energy absorbing action can be obtained as compared with a simple hollow structure.

The second invention to the fourth invention relate to a manufacturing method capable of suitably manufacturing the vehicle resin hood of the first invention, and substantially the same effects as the first invention can be obtained. In the fourth aspect of the present invention, the connecting portion forming recess portion for forming the hinge connecting portion has a nesting structure, and the nesting portion is separated from the front surface side forming die to form the buckling portion. The size of the buckling part whose inside is foamed can be set independently of the hood body, and the impact energy absorption performance of the buckling part can be set separately from the rigidity and impact energy absorption performance required for the hood body. It is possible to further reduce the impact on the human body at the time of a collision.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Polypropylene is preferably used as the resin material of the resin hood for vehicles of the present invention, and the reinforcing fiber has a length of about 5 to 15 mm and a thickness of 5 to 2.
Glass fibers having a long fiber length of about 0 μm are preferably used, but various thermoplastic resins and reinforcements described in, for example, Japanese Patent Application Laid-Open No. 10-305462 and the like are provided within a range in which strength and rigidity required for a vehicle hood can be obtained. Fibers for use can be adopted.

An injection device is preferably used for supplying the molten resin material. For example, the molten resin material may be flowed down and supplied onto the molding surface of the lower mold, and then the upper mold may be lowered to perform compression molding. Various modes can be adopted.

As the hinge connecting member, for example, a screw member such as a bolt or a nut for fixing the resin hood to the hinge is preferably used, but a connecting member other than a screw can be adopted, or the hinge itself. It may be the case of insert molding.

The buckling portion provided between the hood body and the hinge connecting portion is provided, for example, so as to project substantially vertically from the back surface of the plate-shaped hood body, and buckles when a large impact is applied. Composed.

In the second aspect of the invention, the molten resin material is expanded into the foamed state by the action of the springback of the reinforcing fiber and the gas pressure. However, only the springback of the reinforcing fiber is expanded into the foamed state. Other manufacturing techniques can also be used.

According to the third aspect of the present invention, the front side mold and the back side mold are relatively separated from each other so that not only the buckling portion between the hood body and the hinge connecting portion but also the hood body is in a foamed state. However, when carrying out the first invention, the second invention, or the fourth invention, the inside of the hood body does not necessarily have to be in a foamed state.

If necessary, a skin film having a metal foil or the like is provided on the surface of the resin hood. The skin film may be molded and fixed at the same time when the resin hood is molded, but may be molded in a separate body and fixed to the surface of the resin hood with an adhesive or the like. It is possible.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1A and 1B are views showing a vehicle resin hood 10 according to an embodiment of the present invention, in which FIG. 1A is a plan view and FIG.
6 is a sectional view taken along line BB in FIG. The vehicle resin hood 10 is for covering an upper portion of a prime mover chamber in front of the vehicle, and is a flat resin hood body 12 having a substantially constant thickness.
The hinge connecting portions 16 are integrally formed on the rear surfaces of the rear end portion of the hood body 12 on both the left and right sides via columnar buckling portions 14 that project substantially vertically from the hood body 12. It is provided. Hinge connection part 16
Is for attaching the hood main body 12 to the vehicle body so as to be openable and closable, and two bolts 20 integrally fixed to a rectangular metal plate 18 by welding or the like are insert-molded as hinge connecting members. The hinge 22 fixed to the vehicle body is connected by a nut 24. The vehicle resin hood 10 is made of polypropylene in which glass fibers, which are long fibers having a length of about 5 to 15 mm and a thickness of about 5 to 20 μm, are mixed as reinforcing fibers, and the hood is used. The main body 12 and the inside 10a of the buckling portion 14 are in a foamed state (porous), and the surface layer portion 10b and the hinge connecting portion 16 thereof form a dense and solid outer shell structure.

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.
An upper mold 34 and a lower mold 3 that are vertically movable above the
An injection device 36 that injects and supplies a molten resin material into a cavity formed by the upper mold 34 and the gas injection device 38 that injects gas such as air into the molten resin material. The lower mold 32 is provided with a 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, and the molding surface 32f is filled with the molten resin material by the injection device 36. An injection port for injection, a gas injection port for supplying gas by the gas injection device 38, and the like are provided. Molding surface 32f
Has a substantially flat shape as a whole corresponding to the hood body 12, but a portion for forming the buckling portion 14 and the hinge connecting portion 16 has a connecting portion forming recess 32 corresponding thereto.
s is provided. Further, the upper mold 34 is provided with a substantially flat molding surface 34f having the same shape as the upper surface of the target vehicle resin hood 10, that is, the outer surface of the hood body 12, and is vertically driven by a hydraulic type or a mechanical type. By being moved up and down by the device, the lower mold 32 is moved closer to and away from the lower mold 32. The lower die 32 is a back side molding die,
The upper mold 34 corresponds to the front surface molding mold.

First, the recess 3 for forming the connecting portion of the lower die 32 is formed.
After arranging the metal plate 18 with the bolt 20 fixed in 2s, the upper mold 34 is lowered to a predetermined lower position as shown in FIG.
0 raw material, that is, a molten resin 40 of polypropylene in which glass fibers are substantially uniformly dispersed is injected and filled between the lower mold 32 and the upper mold 34, and the vertical dimension, that is, the dimension of the hood body 12 in the plate thickness direction. Holds a predetermined compressed state in a cavity smaller than the target size. As a result, the surface layer portion of the molten resin 40, that is, the portions near the molding surfaces 32f and 34f, and the metal plate 18 in the coupling portion molding recess 32s.
The hinge connecting portion 16 on which the above parts are arranged is cooled first to form a slightly hardened hardened layer. FIG. 2 shows a compression molding process.

Thereafter, before the molten resin 40 inside the hardened layer is cooled and hardened, the upper mold 34 is raised to a position having a target dimension as shown in FIG. By injecting a gas into the glass 40, the molten resin 40 is expanded into a foamed state by the action of the springback phenomenon of the glass fiber and the gas pressure, and is cured in that state. As a result, as shown in FIG. 1, the interior 10 of the hood body 12 and the buckling portion 14 are
The vehicle resin hood 10 having an outer shell structure in which a is in a foamed state and the surface layer portion 10b and the hinge connecting portion 16 thereof are in a dense and solid state is obtained. FIG. 3 shows an expansion molding process.

The vehicle-made resin hood 10 of the present embodiment as described above is provided between the hood body 12 and the hinge connecting portion 16.
Since the buckling portion 14 having an outer shell columnar structure in which the inside 10a is in a foamed state and the surface layer portion 10b is dense is integrally provided, the buckling of the buckling portion 14 provides an excellent collision energy absorbing action, and the hinge. The impact (impact) on the human body at the time of a secondary collision around 22 is mitigated. In particular, since the inside of the buckling portion 14 is in a foamed state, a more excellent collision energy absorbing action can be obtained as compared with a simple hollow structure.

Although the lower die 32 is integrally formed in the above embodiment, as shown in FIG. 4, the connecting portion forming recess 32 is formed.
The portion forming s is formed separately by the nest 42,
The nest 42 can also be independently driven up and down. In that case, in the expansion molding step, the nest 42
By lowering the hood by a predetermined dimension, the hood body 12
Since the size of the buckling portion 14 in which the inside 10a is foamed can be set independently of the above, the impact energy absorbing performance of the buckling portion 14 can be set separately from the rigidity and the impact energy absorbing performance required for the hood body 12. It can be set, and the impact on the human body during a collision can be further mitigated.

Although the embodiment of the present invention has been described in detail with reference to the drawings, it 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 a vehicle resin hood which is an embodiment of the present invention, in which (a) is a plan view and (b) is a sectional view taken along line BB in (a).

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 an expansion molding process when a vehicle resin hood is manufactured using the press molding apparatus of FIG.

FIG. 4 is a diagram illustrating another example of a press molding apparatus that can manufacture the resin hood for a vehicle of the present invention, and is a diagram corresponding to FIG. 3.

[Explanation of reference symbols] 10: Resin hood for vehicle 10a: Inside 10
b: surface layer 12: hood body 14: buckling portion
16: Hinge connecting portion 20: Bolt (hinge connecting member) 22: Hinge 32: Lower die (back side molding die)
32s: Recessed part molding recess 34: Upper mold (front surface molding mold) 40: Molten resin 42: Nesting

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI theme code (reference) B29L 31:30 B62D 25/10 E (72) Inventor So Sato 1 Toyota-cho, Toyota-shi, Aichi Prefecture Toyota Automobile In-house F-term (reference) 3D004 AA04 BA02 CA02 4F206 AA11 AB02 AB25 AD03 AD18 AD23 AG20 AG21 AH18 JA07 JB12 JF04 JF05 JM05 JN25 JN27

Claims (4)

[Claims] 1. A resin hood main body for covering a front part of a vehicle, and a hinge connecting member formed by insert molding on a rear surface side of a rear end portion of the hood main body in order to openably and closably attach the hood main body to a vehicle body. In a vehicle resin hood having a hinge connecting part, the hood main body and the hinge connecting part are made of a resin material mixed with reinforcing fibers, and the hood main body and the hinge connecting part are provided. A resin-made hood for vehicles, characterized in that a buckling portion having an outer shell columnar structure in which the inside is foamed and the surface layer portion is dense is integrally provided between them. 2. A resin hood main body for covering a front part of the vehicle, and a hinge connecting member is insert-molded on the rear surface side of the rear end of the hood main body so that the hood main body can be opened and closed. A method for manufacturing a vehicle-made resin hood having a hinge connecting part and a pair of front side molding dies and back side molding dies, the method being provided on the back side molding dies corresponding to the hinge connecting parts. The hinge connecting member is set in the formed connecting portion forming recess, and the molten resin material containing the reinforcing fibers is brought into a predetermined compressed state in the cavity between the back side forming die and the front side forming die. By holding, a compression molding step of curing the surface layer portion of the resin material including the hinge coupling portion, and at least the coupling portion molding recess portion of the back surface side molding die is relatively opposed to the front surface side molding die. Causes spaced, the gas injected into the molten resin material before internal curing,
By expanding the molten resin material into a foamed state by the action of springback and gas pressure of the reinforcing fiber,
An expansion molding step of forming a buckling portion having an outer shell columnar structure with a dense inner layer and a dense outer layer portion between the hood body and the hinge connection portion, and a resin hood for a vehicle. Manufacturing method. 3. In the expansion molding step, the front surface side molding die and the back surface side molding die are relatively separated from each other, and the hood body also has an outer shell structure in which the inside is foamed and the surface layer portion is dense. It is a thing, The manufacturing method of the resin hood for vehicles of Claim 2 characterized by the above-mentioned. 4. The connecting portion molding recess portion of the rear surface side molding die has a nesting structure capable of being partially separated from the front surface side molding die. The method for manufacturing a resin hood for vehicles according to claim 2 or 3, wherein the buckling portion is formed apart from the front surface side mold.