JPS6351890B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for molding an automotive sunshade, and more particularly to a method for molding an integrally molded synthetic resin automotive sunshade having a reinforcing insert.

A sunshade for an automobile is attached to the rear window of an automobile and is used for the purpose of blocking sunlight and other light entering the vehicle from above without obstructing the rear view. The main body of this Sunshade is the blade,
Usually, a frame body is required to fix the position of the blade and to attach it to an automobile, and a rib is required to prevent the blade from sagging or deforming. Conventionally, this sunshade was mainly composed of a combination of metal plates.
In addition, some of them were made of synthetic resin, especially the blade, and were constructed with metal frames and ribs. However, these sunshields are relatively heavy and do not meet the goal of reducing the weight of automobiles in recent years. On the other hand, the method of combining the blade, frame, and ribs requires a lot of time and effort to manufacture, and the manufacturing cost is high.

Therefore, the present inventor considered making the sunshade an integrally molded product made of synthetic resin. Sunshield has a relatively complicated shape, so it is relatively difficult to integrally mold it using a thermoplastic resin injection molding method. For example, in order to form a thin blade part, it is necessary to inject a synthetic resin with good flowability at high pressure, which requires a large and high-performance injection molding device. Furthermore, even if an integrally molded sunshade can be obtained by injection molding of a thermoplastic resin, a sunshade made only of synthetic resin is considered to be insufficiently durable and easily deformed.

Therefore, the present inventor considered integrally molding the Sunshade using a molding method in which a curable liquid synthetic resin raw material is injected into a mold and hardened. In this method, since the synthetic resin raw material is initially a liquid with relatively good flowability, it can be easily injected into a thin part such as a blade forming part of a mold. On the other hand, by arranging reinforcing inserts in advance in the required portions of the mold and performing molding, it is possible to obtain a sunshade having a reinforcing material inside. As a result, a sunshade with high strength that does not cause deformation or the like can be obtained. In the above-mentioned ordinary injection molding method, it is impossible to perform molding by placing a relatively large insert in the mold, and this becomes possible only by using a liquid synthetic resin raw material with better flowability.

The present invention relates to a method of molding an integrally molded sunshade made of synthetic resin. That is,
The present invention is a method for molding a synthetic resin automobile sunshade consisting of a blade, a frame body, and a rib, in which hard inserts are respectively disposed in a bonded state in cavity portions in a mold forming the frame body and ribs. , a method for molding an automotive sunshield, characterized by injecting a curable liquid synthetic resin raw material into a mold and curing it to obtain an integrally molded product consisting of a blade, a hardened insert reinforcing frame, and a hard insert reinforcing rib. be.

The sunshade obtained by the present invention will first be explained with reference to the drawings. FIG. 1 is a plan view showing an example of the sunshade of the present invention, FIG. 2 is a cross-sectional view taken along line A-A' in FIG. 1, FIG. 3 is a cross-sectional view taken along line B-B', and FIG. -C' sectional view. Sunshade has 8 blades 1, surrounding frames 2 and 3
It is composed of book ribs 3. FIG. 2 shows a cross section of the upper and lower frames 2 and the blade 1 between them. A pipe-shaped insert 4 is arranged inside the frame 2. Note that plate-shaped inserts are arranged inside the left and right frames. FIG. 3 is a cross-sectional view of the surface portion of the flat insert 5 placed inside the rib 3. As shown in FIG. The flat insert 5 has a plurality of holes 6, and the pipe inserts 4 are inserted into the holes at both ends. The other holes 6 are filled with resin constituting the sunshade, and spacers 7, which will be described later, penetrate into the other holes 6. FIG. 4 shows a cross section of the rib 3 and the flat insert 5 therein, as well as a cross section of the blade 1.

Although the sunshade shown in FIGS. 1 to 4 is a preferred example of the sunshade of the present invention, the sunshade of the present invention is not limited to this shape or configuration. In FIGS. 1 to 4, the inserts 4, 5 are arranged in all parts of the frame 2 and the ribs 3, but the inserts can also be arranged partially. For example, it is also possible to arrange the insert only in a part of the frame 2 or only in a part of the rib 3. However, even if only partially, the insert in the frame 2 must be connected to the insert in the rib 3, and similarly, even if only partially, the insert in the rib 3 must be connected to the insert in the rib 3. It is necessary that it is connected to the insert in the frame body 2. This bonding between the inserts is necessary to improve the strength of the sunshade, and without this bonding, sufficient mechanical strength cannot be obtained. Of course, the coupling means are not limited to the illustrated penetration coupling means. Although these shapes and configurations are not limited to those shown, it is important to note that both ends of the inserts 5 in the ribs 3 are connected to both of the inserts 4 in the upper and lower frames 2. The insert 5 is arranged in the frame body 2, and the insert 4 is arranged in any of the four circumferential frames 2.
It is preferable to Sunshade in terms of mechanical strength. Although the shape of the inserts 4 and 5 is not limited, it is preferable that the insert 5 disposed in the rib 3 has a flat plate shape, and the insert 4 disposed in the frame 2 may be a pipe-shaped insert, a plate-shaped insert, or a bar-shaped insert, etc. can also be used. However, in order to fully achieve the above object, sunshades having the configurations shown in FIGS. 1 to 4 are most preferable.

The sunshade obtained by the present invention is an integrally molded product obtained by curing a curable liquid synthetic resin raw material in a mold. Synthetic resins obtained by curing curable liquid synthetic resin raw materials include polyurethane resins, epoxy resins, unsaturated polyester resins, vinyl ester resins, polyamide resins,
There are other things. Particularly preferred is polyurethane resin. Although these synthetic resins can be used alone, it is preferable to mix fillers in order to increase the strength and rigidity of the synthetic resin. As the filler, chopped glass fiber strands, milled glass fibers, wollastonite, and other reinforcing fibrous fillers are preferred. However, the filler may also be calcium carbonate, aluminum hydroxide, clay, other powder fillers, or other fillers. These synthetic resins will be further explained in the later explanation of the molding method.

The material of the insert is not particularly limited as long as it is hard, but iron, aluminum, and other metals are preferable. As the insert other than metal, it is possible to use a material with higher strength and rigidity than the synthetic resin of the Sunshade body, such as FRP (fiber reinforced synthetic resin).

Next, a method for molding the sunshade will be described. First, a mold that is usually divided into upper and lower parts is prepared. This mold has a molding space (cavity) inside.
The curable liquid synthetic resin raw material is cured in this cavity to form sunshade. The shape of this cavity is necessary so that the sunshade can be integrally molded. Below, the cavity is the blade molding part,
The method of molding the sunshield shown in FIGS. 1 to 4 will be explained by dividing it into a frame molding section and a rib molding section. In a mold consisting of an upper mold and a lower mold, the inserts are first placed in the required portions of the cavity before the molds are brought together. If the pipe-shaped insert 4 is placed as it is in the frame forming part of the cavity, it will come into contact with the inner surface of the mold, resulting in the insert 4 being placed on the frame surface after molding.
There is a risk that the surface of the product may be exposed. Therefore, it is preferable to provide a means for preventing the insert 4 from coming into contact with the inner surface of the mold, and it is even more preferable to provide a fixing means that prevents the insert 4 from moving much due to resistance caused by the flow of the synthetic resin raw material during molding. . Therefore, it is preferable to use a spacer to separate and position the insert 4 and the inner surface of the mold, and this spacer is more preferably a spacer 8 coupled to the insert 4. FIG. 5 is a partial perspective view of the pipe-shaped insert 4 to which two spacers 8 are attached. 6th
The figure is a partial cross-sectional view of the mold showing a portion where this pipe-shaped insert 4 is arranged in a frame forming portion 11 of a cavity formed between an upper mold 9 and a lower mold 10, and a blade forming portion 12 of the cavity. .

FIG. 7 shows a plate-shaped insert 5 placed in the rib 3.
FIG. 4 is a partial perspective view showing the connecting portion of the pipe-shaped insert 4. FIG. Since the pipe-like insert 4 penetrates into the plate-like insert 5, the plate-like insert 5 does not come into contact with the lower part of the inner surface of the lower mold. However, since this plate-shaped insert 5 may move laterally and come into contact with the inner side of the mold, it is preferable to further attach a second spacer 13. This second spacer 13 is preferably attached to a part of the hole 6 of the plate-shaped spacer 5 or attached to the surface of the plate-shaped insert 5 with an adhesive or the like. FIG. 8 is a partial cross-sectional view showing the insert 5 placed in the rib forming portion 11 of the cavity between the upper mold 9 and the lower mold 10. It can be seen that the second spacer 13 can prevent the surface of the plate-shaped insert 5 from coming into contact with the inner side of the lower die 10. Further, as shown in FIG. 7, the plate-shaped insert 5 preferably has holes 6 in addition to the attachment portion of the second spacer 13. This is effective in increasing the adhesive strength between the insert and the main body synthetic resin and reducing the weight of the insert. One of the reasons for using the pipe-shaped insert 4 is to reduce the weight of the insert.
Even when the insert in the frame is a plate-shaped insert, it is preferable to provide a hole.

Although the material of the spacer is not particularly limited, its surface may be exposed on the surface of the sunshade after molding, so it is preferable to consider countermeasures in advance. For example, it is preferable that not only the mounting position but also the appearance, such as color, does not deteriorate the appearance of the synthetic resin of the main body. moreover,
It is also necessary to have good adhesion to the synthetic resin of the main body. Therefore, it is preferable to use a synthetic resin that has a high affinity with the synthetic resin of the main body, especially a synthetic resin of the same type.

After the insert and the like are placed in the cavity as described above and the upper and lower molds are brought together, a curable liquid synthetic resin raw material is injected into the cavity.
A high-pressure method and a low-pressure method can be used to inject the liquid synthetic resin raw material, and in particular, a reaction injection molding method called the RIM method is used. The RIM method is already a well-known molding method and is suitable for molding polyurethane, but it is also known that it can be used for molding epoxy resins, unsaturated polyester resins, polyamide resins, etc. This method is
This is a molding method in which at least two highly reactive liquid synthetic resin raw materials are mixed immediately before being injected into a mold, and then injected into the mold and reacted within the mold for a short time to form a synthetic resin. The liquid synthetic resin raw materials are usually mixed by an impingement mixing method, and therefore the liquid synthetic resin raw materials are processed to a relatively high pressure. In this method, a filler-filled synthetic resin molded article can be obtained by mixing a filler into at least one of the liquid synthetic resin raw materials, and separately from at least two liquid synthetic resin raw materials. Fillers can also be mixed in at the same time as mixing. For example, in the RIM method for polyurethane, one liquid synthetic resin raw material usually has a polyisocyanate compound as its main component, and the other liquid synthetic resin raw materials have a polyol as its main component. When filling milled glass fibers or chopped strands, it is preferable to disperse them in at least one of these two liquid synthetic resin raw materials in advance. During molding, two liquid synthetic resin raw materials are collided and mixed in a high-pressure mixing device, and immediately injected and filled into a cavity in a mold. The mixed curable liquid synthetic resin raw materials immediately react to form polyurethane.

As a low pressure method, there is a method in which a liquid synthetic resin raw material with relatively low reactivity is injected into a mold at a relatively low pressure. For example, in the molding of FRP, a molding method called resin injection is equivalent. In this method, for example, an unsaturated polyester resin and its curing agent are mixed and gradually injected into the mold, and since the resin is not very reactive, it will not harden midway even if the injection time is long. .

In the molding method of the present invention, the RIM method is particularly preferred. Although this method is a high-pressure method, injection is performed at a much lower pressure in the mold than in injection molding methods for thermoplastic resins. This is because what is injected is not a high viscosity molten synthetic resin but a low viscosity liquid synthetic resin raw material. The mixed mixture of at least two liquid synthetic resin raw materials initially has a low viscosity and is easily and completely filled into a thin cavity part such as a blade molding part. Therefore, it is particularly suitable for integral molding of molded products with thin parts such as blades and molded products with complicated shapes.

EXAMPLE A sunshade having the shape shown in the figure was molded using the RIM method using glass fiber reinforced polyurethane. The shape and structure of the sunshade are as follows.

Size: 900 x 400 x 14mm Blade thickness: 2.0mm Blade width: 45mm Upper and lower frame cross-section: 8 x 8mm Left and right frame cross-section: 14 x 6mm Rib cross-section: 12 x 6mm Upper and lower frames Inserts inside the body: Length 996mm, diameter 4mm aluminum pipe Inserts inside the left and right frames and ribs: 396 x 10 x
2mm aluminum plate The inserts in the upper and lower frames and the inserts in the left and right frames and ribs are connected as shown in Figure 7.

The spacer (made of polyurethane) is attached as shown in Figures 5 to 8.

Liquid synthetic resin raw material: combination of modified MDI and polyether polyol containing glass fiber milled fiber Molding time: 5 minutes (2 minutes for assembling the mold such as arranging the inner insert) Sunshield weight: 1.5Kg (sunblade of the same shape The weight of the one composed of a polyprolene blade and iron plate is approximately 2.8 kg)

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an example of the sunshade of the present invention, Fig. 2 is a cross-sectional view taken along A-A', Fig. 3 is a cross-section taken along B-B', and Fig. 4 is a cross-sectional view taken along C-C'. FIG. Fig. 5 is a perspective view of the insert placed in the frame, Fig. 7 is a perspective view of the insert placed in the rib, and Figs. 6 and 8 show the respective inserts placed in the mold. FIG. 1...Blade, 2...Frame, 3...Rib,
4, 5...insert.

Claims (1)

[Claims] 1. A method for molding a synthetic resin automobile sunshield comprising a blade, a frame body, and a rib, in which a hard insert is bonded to each cavity in a mold forming the frame body and ribs. A sunshade for an automobile, characterized in that a curable liquid synthetic resin material is injected into the mold and cured to obtain an integrally molded product consisting of a blade, a hard insert reinforcing frame, and a hard insert reinforcing rib. molding method. 2. The method according to claim 1, wherein the molding method in which a curable liquid synthetic resin raw material is injected into a mold and cured is a reaction injection molding method. 3. A method according to claim 1, characterized in that at least a portion of the rigid insert is fitted with a spacer and placed in a mold.