JP2010208296A - Resin casting die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin casting die capable of simultaneously obtaining a plurality of cast products which hardly generate insulation defects such as voids. <P>SOLUTION: The resin casting die is equipped with the followings: a plurality of cavities 2a, 2b and 2c for obtaining cast products of predetermined shape; an inlet 3 and branch channels 4a, 4b and 4c, which inject an insulation material into the plurality of cavities 2a, 2b and 2c; respective exhaust channels 5a, 5b and 5c, which are prepared in the opposite side of the inlet 3 and connected to the plurality of cavities 2a, 2b and 2c; a common resin reservoir 6 connected to respective exhaust channels 5a, 5b and 5c; and an exhaust pressurizing means prepared in the common resin reservoir 6 and equipped with exhaust channels 5d and 5e, an exhaust hood 7 and a float 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a resin casting mold that is filled with an insulating material such as an epoxy resin to obtain a plurality of cast products.

  Conventionally, in a resin casting mold in which epoxy resin is filled into a cavity and cured by heating, the epoxy resin is filled into the cavity from the bottom of the resin casting mold. It is known to exhaust residual air in a cavity from an exhaust groove provided on the surface. In the exhaust groove, an exhaust valve floating on the epoxy resin is provided, and when the epoxy resin is filled, the exhaust valve closes the exhaust groove and pressurizes the epoxy resin in the cavity (for example, patent) Reference 1).

Japanese Patent Laid-Open No. 5-64820 (second page, FIG. 1)

  The above-described conventional resin casting mold has the following problems. The resin casting mold is provided with a single cavity, and the productivity of cast products has been reduced. For this reason, it is conceivable to use a plurality of cavities. However, providing exhaust grooves in each of the cavities and providing an exhaust valve increases the number of parts and makes it difficult to assemble the resin casting mold. Let

  For this reason, a resin casting mold provided with a plurality of cavities, which has a small number of parts, can be easily assembled, and can simultaneously obtain a plurality of cast products that are less likely to cause insulation defects such as voids. It was rare.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a resin casting mold capable of simultaneously obtaining a plurality of cast products in which insulation defects are unlikely to occur.

  In order to achieve the above object, a resin casting mold of the present invention includes a plurality of cavities for obtaining a cast product having a predetermined shape, an injection port for injecting an insulating material into the plurality of cavities, and the injection port. Each exhaust groove connected to the plurality of cavities, a common resin reservoir connected to each of the exhaust grooves, and an exhaust pressurizing means provided in the common resin reservoir It is characterized by comprising.

  According to the present invention, the common resin reservoir is connected to the plurality of cavities through the exhaust groove, and the exhaust groove and the exhaust valve are provided in the common resin reservoir. A plurality of cast products that are easy and hardly cause insulation defects can be manufactured at the same time.

The front view which shows the structure of the resin casting mold which concerns on Example 1 of this invention. The front view which shows the structure of the resin casting metal mold | die which concerns on Example 2 of this invention. Sectional drawing which shows the structure of the resin casting metal mold | die which concerns on Example 3 of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  First, a resin casting mold according to Example 1 of the present invention will be described with reference to FIG. FIG. 1 is a front view showing a configuration of a resin casting mold according to Embodiment 1 of the present invention. Note that the resin casting mold is divided into two parts, and one resin casting mold will be described.

  As shown in FIG. 1, three first, second, and third cavities 2a, 2b, and 2c for obtaining a cast product having a predetermined shape are engraved at the center of the mating surface of the mold 1. It has been. An injection port 3 having a semicircular cross section that leads to the outside is provided on the surface of the lower mold 1 in the drawing. The end of the injection port 3 in the mold 1 is branched into three paths, and first, second, and third branch grooves 4a, 4b, and 4c having semicircular cross sections are connected. The first, second, and third branch grooves 4a, 4b, and 4c are connected to the first, second, and third cavities 2a, 2b, and 2c, respectively.

  On the side of the first, second, and third cavities 2a, 2b, and 2c that faces the upper injection port 5 in the drawing, the first, second, and third exhaust grooves 5a and 5b each having a semicircular cross section. 5c are provided and connected to the oval common resin reservoir 6. A fourth exhaust groove 5d having a semicircular cross section is provided in the upper middle portion of the common resin reservoir 6 in the figure, and is connected to a cylindrical exhaust chamber 7 having an outer diameter larger than that of the fourth exhaust groove 5d. A fifth exhaust groove 5 e having a semicircular cross section is provided in the upper portion of the exhaust chamber 7 in the figure, and communicates with the outside of the mold 1.

  The exhaust chamber 7 is provided with an elliptical float 8 made of, for example, a fluorine resin that easily floats on the epoxy resin, and the float 8 has a guide rod 9 that moves freely in the fifth exhaust groove 5e. Is fixed.

  Next, the casting method will be described.

  The mold 1 is placed in a vacuum furnace (not shown) maintained at a predetermined temperature, and epoxy resin is injected from the injection port 3. The epoxy resin flows into the first to third cavities 2a, 2b, and 2c through the first to third branch grooves 4a, 4b, and 4c. In the first to third cavities 2a, 2b, and 2c, the liquid level of the epoxy resin gradually rises and expels residual air from the first to third exhaust grooves 5a, 5b, and 5c.

  When the first to third cavities 2a, 2b and 2c are filled with epoxy resin, the epoxy resin passes through the first to third exhaust grooves 5a, 5b and 5c into the common resin reservoir 6. Flows in. When the epoxy resin is filled in the common resin reservoir 6, the epoxy resin flows into the exhaust chamber 7 through the fourth exhaust groove 5d.

  In the exhaust chamber 7, as the liquid level of the epoxy resin rises, the float 8 also rises and the fifth exhaust groove 5d is closed. Then, the epoxy resin in the exhaust chamber 7, the common resin reservoir 6, and the first to third cavities 2a, 2b, and 2c stops flowing and is pressurized. When the pressure is increased to a predetermined value, the injection of the epoxy resin from the injection port 3 is stopped, and the state is maintained for a predetermined time to cure the epoxy resin. A plurality of cast products can be obtained by releasing the vacuum after curing and releasing the mold. The cast product is put into a heating furnace (not shown) and secondarily cured.

  Thereby, in the first to third cavities 2a, 2b, and 2c, the residual resin is not entrained and the epoxy resin is cured in a pressurized state, so that a plurality of insulation defects such as voids are hardly generated. Can be manufactured. In addition, since only one exhaust chamber 7 is required for the plurality of cavities 2a, 2b, and 2c, the number of parts is small, and the assembly work of the resin casting mold can be facilitated.

  The larger the volume of the common resin reservoir 6, the better. However, by making the common resin reservoir 6 larger than the combined volume of the first to third exhaust grooves 5a, 5b, 5c, the first to third The residual air in the cavities 2a, 2b, and 2c can be easily exhausted. This is because the residual air is pulled by the common resin reservoir 6 and the exhaust in the first to third cavities 2a, 2b, 2c is promoted.

  In the case where the heater is attached to the mold 1 and temperature control is performed, if the temperature in the vicinity of the common resin reservoir 6 is made higher than the temperature in the vicinity of the first to third cavities 2a, 2b, 2c, the common resin The exhaust of the reservoir 6 can be promoted. And exhaust in the 1st-3rd cavities 2a, 2b, and 2c is also promoted.

  Here, residual air in the first to third cavities 2a, 2b, 2c is injected into the fourth exhaust groove 5d, the exhaust chamber 7, the float 8, and the fifth exhaust groove 5e by injecting epoxy resin. , And after filling, the fifth exhaust groove 5e is closed with a float 8 (exhaust valve) to pressurize the epoxy resin, so that it is defined as an exhaust pressurizing means provided in the common resin reservoir 6.

  According to the resin casting mold of the first embodiment, the common resin reservoir 6 is provided in the first to third cavities 2a, 2b, 2c via the first to third exhaust grooves 5a, 5b, 5c. Since the float 8 that closes the fifth exhaust groove 5e by filling the common resin reservoir 6 with the fourth and fifth exhaust grooves 5d and 5e and the epoxy resin is provided in the common resin reservoir portion 6, the number of parts is small. A plurality of cast products that can be easily assembled and hardly cause insulation defects can be manufactured at the same time.

  Next, a resin casting mold according to Example 2 of the present invention will be described with reference to FIG. FIG. 2 is a front view showing a configuration of a resin casting mold according to the second embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the common resin reservoir is inclined. In FIG. 2, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 2, the common resin reservoir 6 is inclined, and a fourth exhaust groove 5d, an exhaust chamber 7, a float 8, and a fifth exhaust groove 5e are provided in a portion closest to the outside of the mold 1. ing.

  As a result, it is easy to exhaust bubbles or the like that are likely to stagnate on the upper surface of the common resin reservoir 6, and as a result, the residual air in the first to third cavities 2a, 2b, and 2c can be easily exhausted. Especially when the vacuum degree of the vacuum furnace is not set to a high vacuum and the epoxy resin filler is cast at a low vacuum of about 1000 Pa so as not to be scattered at the time of casting, the residual air increases, but the common resin reservoir 6 If exhaust is facilitated, exhaust in the first to third cavities 2a, 2b, 2c can be promoted.

  According to the resin casting mold of the second embodiment, in addition to the effects of the first embodiment, it is possible to obtain a plurality of cast products that are less likely to cause insulation defects.

  Next, a resin casting mold according to Example 3 of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view showing a configuration of a resin casting mold according to Example 3 of the present invention. In addition, this Example 3 is different from Example 2 in that a defoaming layer is attached to the common resin reservoir. In FIG. 3, the same components as those in the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 3, an antifoaming layer 10 formed by applying, for example, a fluorosilicone antifoaming agent is provided on the inner surface of the common resin reservoir 6. Thereby, in the common resin reservoir 6, it is possible to prevent stagnation of bubbles and facilitate exhaust.

  According to the resin casting mold of the third embodiment, in addition to the effects of the second embodiment, the defoaming layer 10 also serves as a release agent, so that removal of burrs and the like is facilitated.

1 Mold 2a, 2b, 2c Cavity 3 Inlet 4a, 4b, 4c Branch groove 5a, 5b, 5c, 5d, 5e Exhaust groove 6 Common resin reservoir 7 Exhaust chamber 8 Float 9 Guide rod 10 Defoaming layer

Claims (4)

A plurality of cavities to obtain a cast product of a predetermined shape;
An inlet for injecting an insulating material into the plurality of cavities;
Each exhaust groove provided on the side facing the inlet and connected to the plurality of cavities;
A common resin reservoir connected to each of the exhaust grooves;
A resin casting mold comprising: an exhaust pressurizing unit provided in the common resin reservoir.   2. The resin casting mold according to claim 1, wherein the common resin reservoir portion is inclined and the exhaust pressurizing means is provided in a portion where the common resin reservoir portion is closest to the outermost side.   The resin casting mold according to claim 1 or 2, wherein a defoaming layer is provided on an inner surface of the common resin reservoir.   4. The resin casting mold according to claim 1, wherein a volume of the common resin reservoir is larger than that of the exhaust groove. 5.

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