JPH0425422A - Burying method for insert into synthetic resin molding and the resin molding - Google Patents

Abstract

PURPOSE:To simultaneously mold a required molded form with an insert buried thereinto by fitting the insert to a block for holding and providing this fitted insert to the prescribed part in an injection molding cavity and filling resin for a raw material. CONSTITUTION:The top force 4 of a forming mold is removed and thereafter glass fiber web G1 for reinforcing a molded form is spread on the inner surface of a cavity 5. Then an insert 1 is fitted to a block 2 for holding and this block 2 is wrapped with glass fiber web G2. thereafter the block 2 is placed on the glass fiber G1 in the position correspondent to an auxiliary cavity 5a. The other glass fiber web G3 is overlapped on the glass fiber web G1, G2 and then the top force 4 is covered and mold clamping is performed. In this state, resin for a raw material is introduced from an filling port 6. When the insides of the molding cavity 5 and the auxiliary cavity 5a are decompressed, the resin for the raw material is spread to all corners of the gaps of glass fiber web G1-G3. When the filled resin is cured and the mold is released, a required panel A is obtained into which the insert 1 is integrally buried.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Application Field) The present invention provides a method for integrating an insert into a synthetic resin molded body when molding a synthetic resin, especially fiber reinforced plastic, by an injection molding method or the like. The present invention relates to a method of embedding the object in a plastic container, and a synthetic resin molded article formed by this method.

(Prior Art) Conventionally, a method shown in FIG. 13 has been used to bolt a vehicle ceiling panel made of, for example, fiber reinforced plastic (hereinafter referred to as FRP) to a beam material of a vehicle body.

That is, prepare a Z-shaped metal fitting 53 to which a nut 52 is welded,
The base was temporarily fixed to a predetermined location on the upper surface of the ceiling panel 51 using putty 54, and the surrounding corners were filled in. It was embedded as shown in 5.

This ceiling panel 51 with metal fittings has bolts 5 for its installation.
7 was screwed into the nut 52 via the beam material 5G, thereby fixing it to the beam material 5G.

According to this method, there is no need for the bolts to pass through the ceiling panel and be exposed on the underside, resulting in an unsightly problem.

In addition, Fig. 14 shows an FRP pumper G1 for automobiles.
Another conventional example is shown in which the side end portions 61a are bolted to the chassis 62. A U-shaped metal fitting 64 with a nut $3 welded to the inner surface of the both side end portions G1a is attached, and its base is fixed as described above. Similarly, it was embedded between the upper 5 side end portion 61a of 6 FRP layers formed by the hand lay-up method.

Also in this case, the mounting bolts G6 of the bumper G1 do not need to be exposed on the outer surface of the side end portion of the bumper 61.

(Problems to be Solved by the Invention) In the above two conventional examples, in order to fix the metal fitting 53 or fi4 to which the nut is welded to the ceiling panel 51 or the bumper 61, putty is not used to temporarily fix it, and the metal fitting 53 or fi4 with a welded nut is not temporarily fixed using putty. Since the FRP layer is formed by the up method, which requires extremely inefficient manual work, productivity is extremely low, and the metal fitting S3. The joint strength of G4 was far from perfect. Furthermore, the hand lay-up method has health management problems in that workers are exposed to harmful gases such as styrene monomer.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for efficiently embedding metal fittings (inserts) during injection molding of synthetic resin, especially FRP, in cases such as those shown in the above conventional example, and An object of the present invention is to provide a synthetic resin molded article having a novel configuration.

[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the method for embedding an insert in a synthetic resin molded body according to the present invention is as follows: Insert 1.11.2
1.31, its holding block 2.12.22.32
The holding block 2 is attached to the mold cavity 5 of the injection mold, and then the mold cavity s is filled with raw resin.

The holding blocks 2 are preferably made of hard synthetic resin foam or the like.

Furthermore, the synthetic resin molded body in which the insert is embedded according to the present invention includes the insert 1.11.21.31 and the holding block 2.12 made of a hard synthetic resin foam and having an arbitrary shape.
．． The configuration was such that it was attached to 22.32 and embedded.

(Function) The insert is attached to a holding block 2 made of, for example, hard foamed synthetic resin and has an arbitrary shape, and this holding block 2 is then placed in a synthetic resin molding mold. If the molding cavity 5 is placed at a predetermined location in the molding cavity S, and raw resin is filled into the molding cavity 5 in this state, a synthetic resin molded body in which the inserts are integrally embedded is molded.

At the same time, the holding block 2 is attached to the synthetic resin molded body.
A reinforcing structure for the protrusions or protrusions is formed near the buried location.

(Embodiment) Below, with reference to FIGS. 1 to 6, the first embodiment of the present invention will be described.
An example will be explained.

As shown in FIG. 6, this embodiment exemplifies the case where a panel A made of FRP as a synthetic resin molded body is bolted to the lower side of its mounting frame B using mounting bolts 3. .

As shown in Fig. 4, the insert 1 to be buried in this panel A is made of a metal strip of a predetermined length, and after being embedded in the molded body, a wire hole is drilled from outside the molded body using a drill or a tap. 1a is provided.

The insert 1 is embedded in the holding block 2 with its upper surface exposed flush with the upper surface of the holding block 2.

The holding block 2 is a columnar body having a trapezoidal cross section, and in this case is made of rigid polyurethane foam with a foaming ratio of about 30 times.

In order to attach the insert 1 to the holding block 2 in an embedded state as described above, it is necessary to perform so-called integral foam molding, in which the insert 1 is placed in advance in the molding cavity when the holding block 2 is foam-molded. Alternatively, the heated insert 1 may be press-fitted into the upper surface of the holding block 2 made by cutting, or a method such as bonding may be adopted.

Next, in Figures 1 to 3 showing the method of molding panel A with insert 1 embedded in a predetermined location, 3 and 4 are the lower and upper molds of the injection mold for molding panel A. The lower mold 3 is provided with a tray-shaped molding cavity 5, and the upper mold 4 is provided with an auxiliary cavity 5a having a trapezoidal cross section at a predetermined location for arranging the insert 1.

The volume of the auxiliary cavity 5a is set to be large enough to surround the outer periphery of the holding block 2 with a gap approximately the same thickness as the thickness of the panel A when the holding block 2 is supported in the center of the auxiliary cavity 5a. ing. G is a filling port provided in the upper mold 4 for filling the raw material resin.

In FIG. 3 showing a cross section of the panel A in which the insert 1 is embedded integrally, 1 is a coating resin layer that covers the outer peripheral surface of the holding plate 2 with a thickness corresponding to the gap.

Next, the operation of the above configuration will be explained.

First, as shown in Fig. 1, the upper mold 4 of the mold was removed, and a glass fiber web G1 reinforcing the molded body was spread over the inner surface of the molding cavity 5.Then, the insert 1 was attached. The holding block 2 is wrapped in a glass fiber web G2 and placed on the glass fiber G1 at a position corresponding to the auxiliary cavity s&. Finally, add another glass fiber web G3, glass fiber web Gl, G2
The upper mold 4 is placed on top of the upper mold 4 and the mold is clamped.

In this state, the raw resin is injected from the filling port 6 into the molding cavity 5. When the pressure inside the auxiliary cavity Sa is reduced, the raw resin spreads to every corner of the voids of the glass fiber webs G1 to G3. If the mold is removed after the filled resin has hardened, the third
A desired panel A shown in the figure in which the insert 1 is embedded can be taken out.

The holding block 2 buried together with the insert 1 in this completed panel A is in a state of being embedded in the coating resin layer 7 formed in the gap of the auxiliary cavity 5a.

In order to provide the wire holes 1a for the mounting bolts 8 in the insert 1 embedded in the completed panel A as shown in FIG. Then, post-processing such as screwing a tapper into this hole may be performed.

To assemble panel A to mounting frame B, the mounting bolts inserted into the bolt holes of mounting frame B are screwed into the wire holes 1a through the drilled holes in the coating resin layer 1, and this installation work is easy. Complete quickly and reliably.

Then, in this installation completed state, the ridge-like coating resin layer 1 surrounding the holding block 2 in which the insert 1 is embedded plays the role of reinforcing the panel A.

Moreover, the insert 1, which replaces the prior art nut 52.1i3 (FIG. 1314), has a surface area similar to that of this nut 52.1i3 (FIG. 1314). Since it is much wider than $3, the fastening force exerted on panel A by the mounting plate will be widely dispersed, and even if the overall structural strength of panel A is designed to be low, stress failure will occur at the insert attachment point. There is no risk of this occurring.

7 and 8 show a second embodiment in which the present invention is applied to a bumper made of FRP for an automobile, and inserts 11 are embedded in both ends 11& of the bumper 1@.

The insert 11 made of iron plate has a wire hole 1 into which a bumper mounting bolt (as shown) is screwed after the bumper 10 is formed.
1M is drilled.

12 is a holding block to which this insert 11 is attached, and has the shape shown in FIG.

The manufacturing method of this bumper 11 is similar to the above embodiment, so its explanation will be omitted.

If both end portions of the bumper 1- are configured in this way, the first
Unlike the conventional model shown in Fig. 4, it is no longer necessary to provide bent portions 11b at both ends that serve as reinforcement and decorative covers. The key point was 2 minutes I'11
An oval mold will be sufficient.

The holding blocks 12 serve to reinforce both ends 10a of the bumper 10 in the same manner as in the embodiment described above.

9 to 11 show a third embodiment in which the present invention is applied to manufacturing a door made of FRP.
As shown in Figure 10, the side end of the hollow FRP door 20 has a wire hole 21. An insert 21 made of a metal strip plate for providing a hinge is buried over substantially the entire length of this side end, and serves as a mounting base for a hinge.

As shown in FIG. 11, this insert 21 is a prismatic holding block 2 made of rigid polyurethane foam.
2, and when the door 20 is injection molded, it is placed at a predetermined position in the mold in the same manner as in the previous embodiment.

In order to attach the hinge 23 to the side end surface of the completed door 20 as shown in FIG. 910, it is sufficient to screw it into the wire hole 21a provided in the insert 21 using the screw 24.

FIG. 12 shows a modification of the third embodiment, in which an insert 3 is embedded in the side end of a hollow FRP door 30.
1 is adhered to the side end surface of a holding block 32 formed in a panel shape that is one size smaller than the door 3Q.

The material of this holding block 32 is the same as that of the first embodiment.

With this configuration, the FRP door 30 can be attached to the hinge 2.
3 is reinforced by an insert 31 made of iron plate, and the inner cavity of the door 31 is filled with rigid polyurethane foam with excellent strength to weight ratio, making the door 30 lightweight and strong. It can be manufactured efficiently.

In each of the above embodiments, the holding block 2°12.
22. The material of 32 is not limited to rigid polyurethane foam, but may also be foamed materials such as phenol resin, vinyl chloride resin, urea resin, etc. If the injection pressure of the raw material resin is low, cardboard may be folded. It may also be something that is made by processing a song.

Also, insert 1.11. - Instead of providing the wire holes 1a and 11a in The shape of the insert force and its embedding method can be modified in various ways, such as by explosive contact.

The synthetic resin molded articles suitable for applying the method of the present invention are, of course, not limited to those of the above embodiments, but can be applied to various molded articles such as boats and housings for various equipment. .

U Effects of the Invention] As is clear from the above description, the method of embedding an insert in a synthetic resin molded body and the synthetic resin molded body in which the insert is embedded according to the present invention have the excellent effects described below.

a) When it is desired to attach an insert (metal fitting) to a synthetic resin molded article made of synthetic resin, especially FRP, place the insert attached to the holding block at a predetermined location within the injection molding cavity. The desired molded body with the insert embedded therein can be molded all at once by simply filling it with the raw material resin.

Therefore, the conventional extremely inefficient and unhygienic manual process of embedding the base of the metal fitting to be attached in an FRP layer formed by the hunt and embedding method is completely eliminated.

b) In order to hold the insert at a predetermined location within the molding cavity, it is sufficient to simply place the holding block with the insert attached thereon, eliminating the need for special holding means that would increase labor and expense.

C) In the synthetic resin molded body made as described above, a protruding or protruding reinforcing structure is naturally formed near the embedding location of the insert, so the mounting strength of the insert is noticeably increased and , the strength of the molded product is also significantly improved.

[Brief explanation of drawings]

Figures 1 to 6 show a first embodiment of the present invention, Figures 1 and 2 are explanatory diagrams of the molding process, and Figure 3 shows the main points of the synthetic resin molded body in which the insert is embedded. Fig. 4 is a partial perspective view of the insert included in the holding block; Fig. 5 is an explanatory view of the insert embedded in the synthetic resin molded body with wire holes provided; FIG. 6 is an explanatory diagram of a state in which a molded resin book is attached to its mounting frame. 7 and 8 show a second embodiment of the present invention applied to a bumper made of FRP for automobiles. FIG. 7 is a cross-sectional view showing the main parts of the bumper, and FIG. FIG. 3 is a perspective view of a holding block with an insert attached thereto. 9 to 11 show a third embodiment in which the present invention is applied to an FRP door. FIG. 9 is a partially cutaway front view, and FIG. 1st cross-sectional view along
1 is a diagram corresponding to FIG. 2, and FIG. 12 is a diagram corresponding to FIG. 10, showing a modification of the third embodiment. 13 and 14 are explanatory diagrams showing different conventional examples, respectively. Code Table 1.11.21.31 Insert 2.12.22.32 Holding block 3 Lower mold
4 Upper mold 5 Molding cavity 6 Filling port A Covering resin layer 1 F dimension bolt 3 Tap 1- Bumper (synthetic resin molded body) 20 Door (synthetic resin molded body) 23 Hinge 24 Screw 30 Door (synthetic resin molded body) la , 11m, 21a, wire hole 5a Auxiliary cavity 1・a Both ends A Panel (synthetic resin molded body) B Mounting frame 01 to G3 Glass fiber web 51 Ceiling panel 52 Nut 53 Metal fitting 54 Putty 55 FRP layer 51i Beam material 57 Bolt bumper Nut FRP layer side end yarn - bent part of metal fitting bolt

Claims (3)

[Claims] (1) Attach the inserts 1, 11, 21, 31 to their holding blocks 2, 12, 22, 32, and place the holding blocks 2... at a predetermined position in the molding cavity 5 of the injection mold. A method for embedding an insert in a synthetic resin molded body, the method comprising: placing the insert in a synthetic resin molded body, and then filling the molding cavity 5 with raw resin. (2) The method for embedding an insert in a synthetic resin molded body according to claim 1, wherein the holding blocks 2 are made of a hard synthetic resin foam. (3) A holding block 2 in which the inserts 1, 11, 21, and 31 are made of hard synthetic resin foam and have an arbitrary shape.
, 12, 22, 32 and embedded therein.