JPS62134205A - Mold for compression molding - Google Patents

Abstract

PURPOSE:To obtain a high quality compression molding form without generating any trouble in post processes by a method wherein an annular body, for forming a recessed part on the compression molding form, is provided at the opening end of a vent hole in the side of a cavity so as to be communicated with the vent hole. CONSTITUTION:An annular body 14 is formed so as to have an outer diameter larger than the inner diameter of a vent hole 13, and is fitted to the vent hole 13 through a hole 15 while the annular body 14 is protruded from the surface of a bottom force 3. Molding material, bond by resin or the like, is put between a top force 2 and a bottom force 3 to mold it through compression molding, when the annular body 14 is fitted into the lower surface of the compression molding form 5. In case, a protruded part 17 is formed in the hole 16 of the annular body 14, however, the height of the protruded part 17 from the lower surface of the compression molding form 5 is sufficiently lower than the height of the annular body 14, therefore, the protruded part 17 will never be protruded from the whole of the lower surface of the compression molding form 5 and smooth molding may be effected as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a compression molding mold for compression molding using wood fibers obtained from wood chips, sawdust, etc.

(Prior Art) Conventionally, there is a mold as shown in FIG. 4 for obtaining wood fibers from pieces of wood, sawdust, etc., bonding them with resin, etc., and compression molding them. This mold 21 forms a cavity 24 having a shape corresponding to the compression molded body 25 between a lower mold 23 and an upper mold 22. The lower mold 23 is mounted on a spacer block 28, and this spacer block 2B is fixed to the base 28 via a press platen 27. A hole 29 is bored in the lower mold 23, and an extrusion bottle 20 for pushing up the compression-molded body 25 when the mold is opened is positioned from below the hole 29, and the upper end thereof passes through the hole 29. Similar to the hole 29 for the extrusion bottle 20, a gas vent hole 33 is provided in the lower die 23 so as to communicate with the cavity 24 for discharging gas, moisture, air, etc. generated during compression molding. .

(Problems to be Solved by the Invention) However, in the configuration of the conventional gas vent hole 33,
The pressure 1i formed as shown in FIG. 5, which is an enlarged version of FIG.
l! The molded body 25 forms a convex portion 37 toward the inside of the gas vent hole 33 at the location of the gas vent hole 33 by compression. This convex part 37 is used as a base on which the compression molded body 25 is placed, for example, when applying a skin such as a plastic material to the surface of the compression molded body 25 in the next step, vacuum suction is applied from the side of the convex part 37. Alternatively, it is necessary to take measures to avoid the convex portion 37 in the mold, which increases manufacturing costs.

Further, if the base and the mold are on a horizontal surface, the convex portion 37 becomes an obstacle to vacuum suction, and a device with a large suction capacity is required.

Therefore, the present invention solves the above problems, and includes:
For compression molding, it is possible to obtain a high-quality compression molded product in which the convex portions produced by compression molding do not cause problems in subsequent processes by communicating the annular body that forms the recesses in the compression molded product with the gas vent holes. The purpose is to provide molds.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides that the opening end on the cavity side of the gas vent hole bored in either the upper mold or the lower mold for compressing the material to be molded. .

The compression molded body has a structure in which an annular body forming a concave portion is provided in communication with the gas vent hole.

(Function) With the above configuration, when the upper mold and the lower mold compress the material to be molded to form a compression molded product, the annular body provided in the gas vent hole fits into the inside of the compression molded product. By pressing the convex parts of the four parts formed on the compression molded body within the height range of the annular body without protruding from the surface of the compression molded body, molding with a smooth overall surface is achieved. It can be achieved.

(Example) Examples of the present invention will be described below based on the drawings. First, FIG. 1 shows a mold l of the present invention in which a compression molded body 5 is molded in a cavity 4 having a predetermined space formed between an upper mold 2 and a lower mold 3. It shows. The material to be molded may be any material that can be compression molded, such as a mixture of wood fiber and resin, etc.
The upper die 2 is a die that can move up and down, and is attached to a press ram (not shown). The lower mold 3 is supported by a spacer block 6, which is attached to a press platen 7. The press platen 7 is attached to the base 8 of the molding machine. A hole 9 is bored in the lower mold 3, and the hole 9 is used to push up the compression molded product 5 after compression molding. An extrusion pin 10 is fitted into the extrusion pin 10, and the extrusion pin 10 can be slid by a drive rod 12 that is vertically movable below via the mounting plate 11.The compression molded body 5 is formed on the tip surface of the extrusion pin IO. When being molded, it is on the same plane as the surface of the lower die 3, and the compression molded body 5
When pushed up, it protrudes from the surface of the lower mold 3. Apart from the hole 9 of the extrusion pin IO, a gas vent hole 13 having a relatively small inner diameter passes through the lower mold 3. The positions of the gas vent holes 13 are provided at a plurality of locations depending on the size of the compression molded body 5. Each of these gas vent holes 1
An annular body 14 of the present invention is formed in the vicinity of the mold 3 facing the upper mold 2. This annular body 14, as shown in FIG.
It is formed into a tubular shape with a diameter larger than the inner diameter of the gas vent hole 13, has a countersunk hole 15 that is fitted into the gas vent hole 13, and is formed so as to protrude from the surface of the lower mold 3. . The annular body 14 is fixed to the slotted hole 15 by caulking the lower mold 3 around the annular body 14 with a saw, or by electron beam welding, etc. The annular body 14 protrudes from the surface of the lower mold 3. Its height is larger than the height of the convex portion 17 from the compression molded body 5 that projects into the hole 16 in the annular body 14 together with the concave portion 17a formed in the compression molded body 5 after compression molding.

On the other hand, in another embodiment of the m-shaped body 14 shown in FIG. It is fixed to the surface of the lower mold 3 by electron beam welding or the like so as to match the hole 13. In this case as well, the height of the annular body 14 is formed to be larger than the height of the convex portion 17 from the four portions 17a formed in the compression molded body 5 after compression molding.

Although two embodiments of the annular body 14 have been described above, the shape of the annular body 14 is not limited to this, and other shapes may be used as long as a depression is formed on the lower surface of the compression molded body 5.

When the mold l having such a configuration is used for compression molding, when a material to be molded bonded with resin or the like is placed between the upper mold 2 and the lower mold 3 and compression molded, the annular body 14 is compressed. It will fit into the lower surface of the body 5. At this time, by compression molding the compression molded body 5, the hole 1B of the annular body 14
A convex portion 17 is formed in the compression molded body 5, but since the height of the convex portion 17 from the lower surface of the compression molded body 5 is sufficiently smaller than the height of the annular body 14, the convex portion 17 is formed from the entire lower surface of the compression molded body 5. There is no protrusion and the molding is smooth overall.

Note that since the tip end surface of the extrusion pin 10 only needs to be maintained on the same plane as the surface of the lower mold 3 during compression molding, it is not necessary to support the drive rod 12, which can move up and down, with a complicated elastic member. This makes manufacturing easier.

In the above embodiments, the upper mold 2 is movable and the lower mold 3 is fixed, but the reverse may also be used.
, the lower mold 3, and the annular body 14 is also formed along it.

Although an example of compression molding of a plate-shaped compression molded body 5 has been described here, compression molding of a sufficiently tall cube is also possible.

(Effects of the Invention) As described above, the present invention provides an annular body in the gas vent hole, so that the convex portion formed on the compression molded body is formed inside the compression molded body rather than on the surface thereof. , high-quality compression molding can be achieved without hindrance in subsequent processes. In particular, in processes such as attaching a skin to a compression molded product, there is no need for expensive bases or molds that take convexities into account, which reduces manufacturing costs.
When attaching the compression molded body to another object, there is an effect that a design that takes convex portions into consideration is not necessary.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing the compression molding mold of the present invention, Fig. 2 is an enlarged view of the gas vent hole in Fig. 1 with an annular body provided therein, and Fig. 3 is an enlarged view showing another annular body. FIG. 4 is a vertical sectional view showing a state of compression molding using a conventional mold. FIG. 5 is an enlarged view showing the state of the gas vent hole and the compression molded body shown in FIG. 4. 1: Mold 2 2 Upper mold 3: Lower mold 4: Cavity 5:
Compression molded body 13: Gas vent hole 14: Li-shaped body 17a
: Concave Patent Applicant: Toyota Motor Corporation Figure 4, Port 5

Claims (1)

[Claims] (1) At the open end on the cavity side of a gas vent hole bored in either the upper mold or the lower mold that compresses the material to be molded, an annular body forming a recess in the compression molded body is communicated with the gas vent hole. A mold for compression molding, characterized in that it is provided with