JPS6129259B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a reinforcing body for forming rib-shaped reinforcing parts that are adhered to plate materials, particularly plate materials used for vehicle body outer panels such as door panels and roof panels, and are foam-cured and integrated with the plate material. Conventionally, as shown in FIG.
Door outer panel 2 [metal plate material 2
A reinforcing material 4 made of a thermosetting resin to which a reinforcing material 3 such as glass fiber or non-woven fabric has been attached in advance is attached to the inner surface of the board a], and the reinforcing material 4 is heated and hardened to reinforce the plate material. It has been known. In addition, 5 in the figure
is a door inner panel, 6 is a door window sash, 7 is a side window glass, and 8 is an outside door handle. However, in this conventional example, the reinforcing material 4
However, the required reinforcing effect cannot be obtained unless the thickness is considerably increased, and the amount of resin material used is large, which increases the production cost and, in particular, increases the weight. It is also known that as another conventional example, a reinforcing material that has been molded and hardened in advance is bonded to a board, but in this case it is necessary to mold the reinforcing material so that it perfectly matches the shape of the board. There were problems in that it was difficult to form the reinforcing material and it was very difficult to completely bond both the reinforcing material and the plate material. Therefore, as shown in FIG. 2 A and B, the present applicant added glass fiber or other reinforcing material 10 directly to the inner surface of the metal plate 2a that is the door outer panel 2 or onto the anti-rust coating 9. We have previously proposed an automobile plate material and a method for producing the same in which a reinforcing material 11 made of thermosetting resin is applied and a bead-shaped bulging portion 12 is formed on the reinforcing material 11 as described later. According to the proposed invention, all of the problems of the prior art described above are solved. By the way, in order to form this bead-shaped bulge 12, a reinforcing body 13 as shown in FIG. 3 is used. This reinforcing body 13 is an uncured thermosetting material in which the reinforcing material 10 is added to an unfoamed foamed material (for example, a band-shaped foamed material 14 such as a foamed polyethylene sheet or a foamed epoxy sheet) that foams when heated. The reinforcing material 11a made of a synthetic resin is laminated in advance. For example, the uncured resin reinforcing material 11a has a thickness of t ₁ 1.0 mm.
A so-called B-stage epoxy resin sheet material is used. However, such a reinforcing body 13 is pasted on the back of the outer panel of the door using the adhesive properties of epoxy resin, and the foam material is expanded using the drying heat of the subsequent painting process to form a bead-like expansion. When forming the protruding portion 2, a phenomenon was observed in which the reinforcing body 13 slipped downward from the portion where it was first attached to the outer panel, although the probability was small. As a result of analyzing this phenomenon, it was found that the reinforcing material did not have sufficient adhesion in areas where the outer panel had a complex shape due to insufficient flexibility of the reinforcing material, and when heated, the epoxy resin It was found that when softening, the adhesive strength decreases, which causes the adhesive to slip off. Therefore, it is desired to manufacture a reinforcing body 13 that can obtain a predetermined strength while preventing this sliding down. According to various subsequent studies and experiments, the thickness t ₁ of the resin sheet forming the bead-shaped bulge 12
It has been found that even if the bulge portion 12 is thin, a sufficient reinforcing effect can be obtained as long as the height h of the bulge portion 12 itself is sufficient. This invention is proposed based on the above knowledge, and specifically includes an unfoamed foam material, an uncured resin material covering at least one side of the foam material, and a surface or a surface of the resin material. This is a reinforcing body for reinforcing a board consisting of a reinforcing material added to the surface part, and by making the thickness of the resin material even thinner, the reinforcing body can be manufactured at a low cost, and it is possible to attach the reinforcing body to the board. The aim is to improve the ability to follow the shape of the plate and to measure the distortion (sink mark) on the surface of the plate material, thereby making it possible to prevent the above-mentioned slipping off. The details of this invention will be explained below based on FIG. 4 and FIGS. 5A and 5B. [In the above and below descriptions, the term "rib-shaped reinforcing portion" means a reinforcing portion having a bead shape or other so-called protrusions. ] 20 is a reinforcing body, which has a thin and flat shape as a whole. This reinforcing body 20 mainly includes an unfoamed foam material 21, an uncured resin material 22 that covers one side of this foam material 21, and a reinforcing material 23 added to the surface or surface portion of this resin material 22. It is composed of. As the foaming material 21, a foamed polyethylene sheet, a foamed epoxy sheet, or the like that foams when heated can be used, and the material is not particularly limited as long as it expands in volume at an appropriate magnification. Therefore, regardless of whether the material is soft or hard, foaming is not limited to foaming by heating, and depending on the case, foaming at room temperature can also be used. The resin material 22 is preferably a thermosetting resin material, such as a thermosetting epoxy resin, but may be a resin material that hardens at room temperature. This resin material 22 has a thickness t ₂
It should be in the form of a thin sheet of 0.5mm to 0.8mm. When the reinforcing body 20 is adhered to the plate material 24 in the direction of arrow A and foamed and hardened to form a rib-shaped reinforcing portion integrated with the plate material, if the thickness t ₂ is less than 0.5 mm, the foamed material 21
During foaming, holes are formed in the resin material 22, and some of the gas generated during foaming leaks outside through these holes, making it difficult to stably form a rib-shaped reinforcing portion with sufficient height. A sufficient reinforcing effect can be obtained up to 0.5 mm, and the same strength as 1 mm can be obtained by increasing the height of the rib. The upper limit of the thickness _t2 is determined from the point of view of the reinforcing material's conformability to the shape of the outer panel of the door.
0.8mm is appropriate. The reinforcing material 23 can be made of glass cloth, glass fiber, carbon fiber, organic nonwoven fabric, kraft paper, or the like, as long as it can be easily integrated with the resin material 22 and can impart toughness to the resin material 22. The thickness t ₃ of the reinforcing material 23 depends on the type of material, but if glass cloth is used, a plain weave of 0.22 mm is preferable. If the thickness _t3 is too thick, the state of penetration of the resin material 22 will be unfavorable, and if it is too thin, the absolute strength will be insufficient.
As the reinforcing material 23, a material adjusted to a suitable thickness _t3 in accordance with the second type is selected. Note that when organic nonwoven fabric is selected as the reinforcing material 23, the improvement in rigidity is small compared to glass cloth and the like, so it is preferable to utilize the advantage of high elongation and use it when a large reinforcing effect is not required. Next, a test example is shown. A reinforcing body 20 is constructed by covering the upper surface of a foamed polyethylene sheet selected as an unfoamed foamed material 21 with a resin material 22 and a reinforcing material 23 shown in the following table, and is attached to a 0.7 mm thick steel plate as a plate material 24. A rib-shaped reinforcing portion with a height of 10 mm was integrally formed on the steel plate by foaming and hardening by applying and heating. When a bending test was conducted, the relationship between the thickness of the resin material and its rigidity was as shown in Figure 5 A, and the relationship between the reinforcing material and its rigidity was as shown in Figure 5 B. Each was obtained.

[Table] According to this test example, even if the thickness t ₂ of the resin material (epoxy sheet) is made thinner, the reinforcing effect does not decrease drastically, and the reinforcing effect of the resin material (epoxy sheet) within the range of _0.5 mm to 0.8 mm If it is a material (epoxy sheet), use the sample shown in Figure 5 A.
As seen from the load displacement curves of No. 3 and No. 2, it was confirmed that they could withstand considerable loads. In addition, for the reinforcing material, the thickness of the resin material was 1 mm for this test.
The glass cloth was tested under thicker conditions than the present invention, and found that a glass cloth thickness of 0.22 mm ^t is optimal, and as the thickness _t becomes thicker, the penetration of epoxy deteriorates and the strength is not achieved. It was found that the strength was insufficient, and that even organic nonwoven fabrics could withstand considerable loads, as shown by the load displacement curve in Figure 5B. Therefore, it can be seen that even if the thickness of the resin material is set to 0.5 to 0.8 mm as in the present invention, the organic nonwoven fabric can be used as the reinforcing material.
Although it was not shown as a graph, when glass cloth is 0.22 mm as a reinforcing material and the thickness _t2 of the resin material (epoxy sheet) is 0.6 mm, a rib shape with a height of 13 mm is formed on a thin steel plate with a thickness of 0.7 mm. When the reinforcement part is formed integrally, the thickness of the resin material is 1 mm and the height of the rib is 10 mm.
The same bending stiffness ratio as in the case of was obtained. In addition, sufficient followability of the reinforcing body to the plate material was obtained. Example 40 parts by weight each of Epikote #828 and #1004 (both trade names manufactured by Yuka Ciel Co., Ltd.) which are bisphenol A type epoxy resins, and 20 parts by weight of Vylon #500 (trade name manufactured by Toyobo Co., Ltd.) which is a polyester resin. 5 parts by weight each of dicyandiamide and Kyuazol (trade name manufactured by Shikoku Kasei Co., Ltd.) as curing agents for epoxy resin, 50 parts by weight of talc and 2 parts by weight of asbestos powder were kneaded and then formed into a sheet with a width of 50 mm and a length of 370 mm. A resin material was formed by cutting glass cloth (WK2020A100 manufactured by Nittobo Co., Ltd.) as a reinforcing material into the same dimensions and laminating them. Next, 100 parts by weight of the above-mentioned Epicoat and Hiker, which is a carboxyl group-containing nitrile rubber, were added.
75 parts by weight of CTBN1300×8 (manufactured by B.F. Gutdrich) were mixed and reacted at 150° C. for several hours. Next, 100 parts by weight of this reaction product, 5 parts by weight of dicyandiamide as a hardening agent, and 4 parts by weight of D, P, Hardener (trade name, manufactured by Maruwa Biochemical Co., Ltd.) and 4 parts by weight of a blowing agent Vinyhole (trade name: AK#2 manufactured by Eiwa Kasei Co., Ltd.) were added.
Thoroughly knead and extrude to a thickness of 1.
A sheet-like unfoamed foam material with a width of 10 mm and 10 mm was prepared and attached to the center of the aforementioned resin material using the adhesive strength of the resin material itself. This reinforcing body is shaped to form part of a cylinder with a radius of approximately 1300 mm, and an accent bead is formed on that part to form two sides of a triangle with a height of approximately 8 mm and a base of approximately 30 mm (vertex is 3R). The reinforcing body is pasted vertically across the ridges on an outer panel of an automobile door having ridges like this on the inside,
Then, it was passed through a drying oven under drying conditions of 140°C x 30 minutes. As a result, the reinforcing body foams and hardens.
A 10mm high rib is integrally formed on the outer panel. Further, the reinforcing body did not slip down in the drying oven at all. Also, when pasting it on, it stuck tightly to the outer panel and had good followability to the outer panel. In this embodiment, the resin material was attached to cover one side of the foam material, but it is also possible to cover three sides of the foam material with the resin material except for the side in contact with the plate material. As explained above, according to this invention,
The unfoamed foam material and the thickness t ₂ covering this foam material are
The present applicant constructed a thin flat sheet material as a whole by using an uncured resin material of 0.5 mm to 0.8 mm and a reinforcing material added to the surface or surface portion of this resin material. Compared to the previously proposed reinforcing body (Fig. 3), the thickness of the resin material is thinner, and it has excellent shape following ability even when the shape of the plate is uneven, and is thermosetting as a resin material. When a plastic resin is used, it has the effect of preventing slippage that occurs during heating, and of course, it can be expected that the strength and rigidity of the plate material will be sufficiently improved compared to the one shown in Fig. 3.

[Brief explanation of the drawing]

Fig. 1A is a front explanatory view of a conventional door; Fig. 1B is an explanatory cross-sectional view taken along the Ro-Ro line in Fig. 1A; Fig. 1C is an enlarged cross-sectional view of C in Fig. Figure A is a perspective explanatory view of the main parts of the door outer panel that has already been proposed as a solution to the conventional example, and Figure 2B is a -
3 is a cross-sectional explanatory view of the reinforcing body before reaching FIG. An explanatory diagram of a load-displacement curve showing the relationship between thickness and rigidity, and the same figure is an explanatory diagram of a load-displacement curve showing the relationship between reinforcing material and rigidity. 1...Door, 2...Door outer panel, 2a...
...Metal plate material, 3,10...Reinforced material, 4,11
... Reinforcement material, 12 ... Bead-shaped bulge, 13,
20... Reinforcement body, 14, 21... Foaming material, 22...
... Resin material, 23 ... Reinforcement material, t ₁ , t ₂ ... Thickness of resin material, t ₃ ... Thickness of reinforcement material, 24 ... Plate material.

Claims (1)

[Claims] 1. An unfoamed foam material, an uncured resin material having a thickness t of 0.5 mm to 0.8 mm that covers at least one side of the foam material, and the surface or surface of the resin material. A reinforcing body for reinforcing plate materials, which is made up of a thin flat sheet-like body with reinforcing material added to the parts. 2. A reinforcing body for reinforcing a plate material according to claim 1, wherein the resin material is a thermosetting epoxy resin. 3. A reinforcing body for reinforcing a plate according to claim 1 or 2, wherein the reinforcing material is glass cloth.