JPH11114968A - Resin molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin molding apparatus capable of molding a resin to produce a precise optical part such as a lens or the like with high accuracy. SOLUTION: Upper and lower molds are formed of a cermet being a composite material of ceramic and a metal or an alloy thereof and, by appropriately selecting the compsn. of the cermet, the heat conductivity of both molds is made larger than that of core pieces 11, 12 and the coefficient of thermal expansion of them is made equal to or less than that of both core pieces 11, 12. Therefore, the temp. distribution generated in the upper and lower molds at a time of molding is reduced to enhance the molding quality of a resin and, by preventing the distortion of the upper and lower molds caused by the internal pressure of a plastic resin at a time of molding, the molding quality of the plastic resin can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding apparatus, and more particularly to a resin molding apparatus capable of molding a precision plastic optical component such as a lens with high precision.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a high-precision resin molded product such as a lens and a mirror, if a temperature distribution occurs in a molding die, sink and residual stress are generated in the molded product, and a high-precision resin is produced. Unable to produce molded article.

[0003] Conventionally, there is provided an opposing piece provided on both a fixed mold and a movable mold which are arranged to face each other, and a molten resin is injected into a cavity formed between the both input pieces. In the injection molding die device to be filled,
A heat insulating material is provided around a plurality of the input pieces constituting the cavity, heat insulation is provided between the input pieces and the fixed mold and the movable mold supporting the input pieces, and a mold for the plurality of input pieces forming the cavity is provided. There has been proposed an injection mold apparatus for maintaining and controlling the temperature at a high precision (Japanese Patent Laid-Open No. 6-114).
885). That is, this injection molding die apparatus is provided with an air gap or a heat insulating portion formed of a heat insulating material having a low thermal conductivity around an input piece constituting a cavity, and a plurality of input pieces constituting a cavity are maintained at a constant temperature. So that they can be maintained.

In addition, the present applicant first processes a plastic base material into a substantially final shape by injection molding in advance, inserts the plastic base material into a mold having a plurality of cavities, and then applies the plastic base material to the mold. Plastic molding in which the injection step and the aging step of melting and heating the material to a temperature equal to or higher than the glass transition temperature of the plastic base material, generating a resin internal pressure caused by the melting and heating, and then gradually cooling to transfer a mirror surface are performed. In a method of manufacturing a product, there has been proposed an aging mold characterized in that the aging mold is made of a member having a high thermal conductivity (Japanese Patent Laid-Open No. 5-1 / 1993).
No. 62139). That is, in this aging mold, the mold member is made of a member having good thermal conductivity, such as aluminum, an aluminum alloy, copper, or a copper alloy.

[0005]

However, in such conventional injection molding apparatus and aging mold, there is still a point of improvement in improving the precision of a sufficient plastic molded product. there were.

That is, in the mold apparatus for injection molding disclosed in Japanese Patent Application Laid-Open No. 6-114885, if the heat insulating portion is formed by an air gap, the heat insulating portion becomes a gap, and the cavity is formed by the internal pressure during molding. There was a problem in that the pieces were distorted and the molding quality deteriorated. Further, when the heat insulating portion is formed of a heat insulating material having a low thermal conductivity, the mold is constituted by a plurality of members, and the coefficient of thermal expansion between the members is different,
When the mold is heated, the input piece is deformed due to the difference in the coefficient of thermal expansion between the members, and there is a problem that burrs are generated at the time of molding and the molding quality is deteriorated.

In the aging mold described in Japanese Patent Application Laid-Open No. 5-162139, when aluminum or an aluminum alloy is used as a mold member, the aluminum or aluminum alloy has low rigidity and is deformed during molding. There is a risk of deteriorating the molding quality, and when copper or copper alloy is used as a mold member, copper or copper alloy has poor mirror workability, so that high-precision plastic parts such as lenses and mirrors are formed. Was inappropriate.

Therefore, according to the present invention, all parts of the upper mold and the lower mold, or a part thereof, has a thermal conductivity of an input piece which has a mirror surface and defines a cavity. The temperature distribution of the upper mold and the lower mold at the time of resin molding is formed by forming a heat conductive member having a thermal expansion coefficient larger than the thermal conductivity and a thermal expansion coefficient equal to or smaller than the thermal expansion coefficient of the input piece. Uniformity prevents distortion of the upper and lower dies, and enables molding of high-precision molded products without sink marks and internal stress, and shortens the molding cycle.
It is another object of the present invention to provide a resin molding apparatus capable of suppressing the occurrence of burrs during molding.

According to a second aspect of the present invention, a cermet which is a composite material of a ceramic and a metal or an alloy thereof is used as a heat conducting member of the upper mold and the lower mold.
By changing the composition of the ceramic and the content of the metal or its alloy to form a heat conductive member having the intended thermal conductivity and thermal expansion coefficient, it is possible to obtain a molded product with higher precision, and a molding cycle. It is an object of the present invention to provide a light-weight and easy-to-handle resin molding apparatus that can be shortened and further suppress generation of burrs during molding.

According to a third aspect of the present invention, the heat conducting member is formed of a cermet formed by casting a molten metal or an alloy thereof into a ceramic and then casting it into a mold having a desired shape. Accordingly, an object of the present invention is to provide a resin molding apparatus which can easily and inexpensively form a heat conductive member having an intended thermal conductivity and thermal expansion coefficient and can mold a high-precision molded product at low cost.

According to a fourth aspect of the present invention, the heat conductive member is formed by infiltrating a molten metal or an alloy thereof into ceramics previously formed in the shape of the heat conductive member of the upper mold and the lower mold. By forming with cermet, the content of metal or alloy constituting cermet is low,
It is an object of the present invention to provide a resin molding apparatus capable of accurately forming a heat conductive member having an intended shape with high precision even when fluidity is low and molding a highly accurate molded product.

According to a fifth aspect of the present invention, a mold heating means for heating the upper mold and the lower mold or a mold cooling means for cooling the upper mold and the lower mold are embedded in the heat conducting member. As a result, the temperature of the upper mold and the lower mold can be efficiently changed by the mold heating means or the mold cooling means to shorten the molding cycle of the resin, and the temperature distribution of the upper mold and the lower mold can be improved. It is an object of the present invention to provide a resin molding apparatus that can further reduce uniformity and mold a molded article with higher precision.

The invention according to claim 6 shortens the molding cycle of the resin by heating the upper mold and the lower mold to a predetermined constant temperature, filling and solidifying the resin, and molding the resin. It is an object of the present invention to provide a resin molding apparatus capable of improving the uniformity of the temperatures of an upper mold and a lower mold during resin molding and further improving the precision of a molded product.

According to a seventh aspect of the present invention, the resin molding cycle is shortened by changing the temperature of the upper mold and the lower mold and molding the resin after filling or inserting the resin into the cavity. It is another object of the present invention to provide a resin molding apparatus capable of improving the uniformity of the temperatures of an upper mold and a lower mold during resin molding and further improving the precision of a molded product.

[0015]

According to a first aspect of the present invention, there is provided a resin molding apparatus comprising an upper mold and a lower mold, and is formed of a member having a predetermined thermal conductivity and thermal expansion coefficient. At least one of an upper mold and the lower mold is provided with an input piece having a mirror surface portion to define a cavity, and a resin molding apparatus for molding a resin filled in the cavity, wherein the upper mold The mold and the lower mold are all parts thereof, or
A part thereof is formed of a heat conductive member whose thermal conductivity is higher than the thermal conductivity of the input piece and whose thermal expansion coefficient is equal to or smaller than the thermal expansion rate of the input piece. As a result, the above object is achieved.

According to the above configuration, all parts of the upper mold and the lower mold, or a part thereof, have a thermal conductivity of
Since the thermal expansion member is formed of a heat conductive member having a mirror surface portion that is larger than the thermal conductivity of the input piece defining the cavity and whose thermal expansion coefficient is equal to or smaller than the thermal expansion coefficient of the input piece, resin The temperature distribution of the upper mold and the lower mold during molding can be made uniform, and the distortion of the upper mold and the lower mold can be prevented.
A high-precision molded product without sink marks and internal stress can be molded, the molding cycle can be shortened, and the occurrence of burrs during molding can be suppressed.

In this case, for example, as described in claim 2, the heat conducting members of the upper mold and the lower mold are
Cermet which is a composite material of ceramic and metal or an alloy thereof may be used.

According to the above construction, since the cermet, which is a composite material of ceramic and a metal or an alloy thereof, is used as a heat conducting member of the upper mold and the lower mold, the composition of the ceramic or the metal or the alloy thereof is determined. By changing the content of, it is possible to form a heat conductive member having an intended coefficient of thermal conductivity and thermal expansion, it is possible to obtain a more accurate molded product, shorten the molding cycle, and, The generation of burrs during molding can be further suppressed, and
Lightweight and easy to handle.

Further, for example, as described in claim 3, the heat conducting member is formed by impregnating a molten metal or an alloy thereof into a ceramic and then casting it into a mold formed into a desired shape. It may be a cermet.

According to the above construction, after the molten metal or its alloy is infiltrated into the ceramic,
Since it is formed of a cermet formed by casting into a mold made into a desired shape, a heat conductive member having an intended coefficient of thermal conductivity and coefficient of thermal expansion can be formed easily and inexpensively, and inexpensively. High-precision molded products can be molded.

Further, for example, as described in claim 4, the heat conductive member is formed by melting metal or metal melted into ceramics previously formed in the shape of the heat conductive member of the upper mold and the lower mold. A cermet formed by infiltrating the alloy may be used.

According to the above construction, the heat conducting member is formed by infiltrating a molten metal or an alloy thereof into ceramics previously formed in the shape of the heat conducting member of the upper mold and the lower mold. Since the cermet is made of a low content of metal or alloy and has low fluidity, it is possible to accurately form a heat conductive member of the intended shape with high precision. Articles can be molded.

Further, for example, as described in claim 5, the heat conducting member is a mold heating means for heating the upper mold and the lower mold, or the upper mold and the lower mold. May be embedded in the mold cooling means.

According to the above configuration, the heat conduction member embeds the mold heating means for heating the upper mold and the lower mold, or the mold cooling means for cooling the upper mold and the lower mold. Therefore, the temperature of the upper mold and the lower mold can be efficiently changed by the mold heating means or the mold cooling means, and the molding cycle of the resin can be shortened. To further reduce the non-uniformity of the temperature distribution of
An even higher precision molded product can be molded.

Further, for example, as described in claim 6, the resin molding device heats the upper mold and the lower mold to a predetermined constant temperature, and then fills and solidifies the resin. The resin may be molded.

According to the above configuration, the upper mold and the lower mold are heated to a predetermined constant temperature, and then filled and solidified to form the resin. It is possible to improve the uniformity of the temperature of the upper mold and the lower mold during resin molding, and to further improve the precision of the molded product.

Further, for example, as described in claim 7, the resin molding apparatus changes the temperature of the upper mold and the lower mold after filling or inserting the resin into the cavity. The resin may be molded.

According to the above configuration, after filling or inserting the resin into the cavity, the resin is molded by changing the temperature of the upper mold and the lower mold, thereby shortening the molding cycle of the resin. In addition to improving the uniformity of the temperatures of the upper mold and the lower mold during resin molding, the precision of the molded product can be further improved.

[0029]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 3 show an embodiment of the resin molding apparatus of the present invention. FIG. 1 shows a resin molding apparatus 1 to which an embodiment of the resin molding apparatus of the present invention is applied. It is principal part front sectional drawing.

In FIG. 1, a resin molding apparatus 1 has a pair of opposed die plates 3a, 3b fixed to a pair of arms 2a, 2b of a press machine (injection molding machine).
Each die plate 3a, 3b has a heat insulating plate 4a,
The upper mold 6 and the lower mold 7 are fixed via the mold 4b and the mold temperature adjusting plates 5a and 5b.

A mold heating member (mold heating means) such as a heater for keeping the upper mold 6 and the lower mold 7 at a constant temperature, respectively, or a high precision mold temperature adjusting plate 5a, 5b. Temperature control units 8a and 8b such as a mold cooling member (mold cooling means) such as a coolant channel controlled at a constant temperature are embedded in the mold, and the mold temperature control plates 5a and 5b are provided with temperature control units. 8
The upper mold 6 and the lower mold 7 are adjusted to a constant temperature by adjusting the temperature by a and 8b.

The temperature adjusting portions 8a and 8b may be formed directly on the upper die 6 and the lower die 7, but may be formed on separate die temperature adjusting plates 5a and 5b. When the upper mold 6 and the lower mold 7 are fixed to each other, the upper mold 6 and the lower mold 7 can be easily formed.

The upper mold 6 and the lower mold 7 have a mirror 1 having a mirror 9 and a mirror 10 at opposing positions, respectively.
1 and the input piece 12 are inserted, and the input pieces 11 and 12
A cavity 13 is defined by the upper mold 6 and the lower mold 7.

The entry piece 11 and the entry piece 12 that define the cavity 13 are required to have rigidity that does not cause distortion during molding and workability of the mirror surface portion 9 and the mirror surface portion 10. It is formed of an excellent member, and is usually formed of an iron-based member.

The upper mold 6 and the lower mold 7 are made of a cermet (heat conductive member) which is a composite material of ceramic and metal or ceramic and metal alloy.
It is formed by a casting method in which a molten metal or metal alloy is infiltrated into ceramic and cast into a mold formed into a desired shape. Thus, when the upper mold 6 and the lower mold 7 are formed by the casting method, the upper mold 6 and the lower mold 7 are formed.
Can be easily and inexpensively formed, and the replica of the upper mold and the lower mold 7 can be formed very easily.

The cermet, which is a member for forming the upper mold 6 and the lower mold 7, has its characteristics and properties by appropriately adjusting the ceramic material and the metal or metal alloy material and the content ratio thereof. In particular, the thermal conductivity and the thermal expansion coefficient can be adjusted. In the present embodiment, the cermet forming the upper mold 6 and the lower mold 7 has a large thermal conductivity and a large thermal expansion coefficient. The same size as the iron-based member which is a material for forming the pieces 11 and 12 is used.

The cermet is made of Si as a ceramic.
C, SiN, Al ₂ O _{3 and the} like can be used, and as the metal, aluminum, copper, zinc, tin, iron and the like can be used, and a cermet having desired characteristics by appropriately adjusting the content ratio thereof. Thus, the upper mold 6 and the lower mold 7 can be formed.

For example, a cermet, which is a composite material of a ceramic and a metal or an alloy, is made of SiC
Using aluminum alloy as the metal, the thermal conductivity, coefficient of thermal expansion, modulus of longitudinal elasticity and density of aluminum alloy, copper alloy and iron-based members, thermal conductivity, coefficient of thermal expansion, When compared with the elastic modulus and the density, the results shown in FIG. 2 were obtained. In FIG. 2, the cermet is described as a composite material. As can be seen from FIG. 2, the cermet has a thermal conductivity of 160 to 180 W /
At m ° C., the thermal conductivity of the iron-based member, which is the forming member of the input pieces 11 and 12, is three times or more larger than that of the aluminum alloy or the copper alloy. The modulus of longitudinal elasticity is 106 to 265 GPa, which is larger than the modulus of longitudinal elasticity of an aluminum alloy or a copper alloy, is equal to the modulus of longitudinal elasticity of an iron-based member, and has a specific gravity of 2.7.
3.0 or less, which is less than half of that of iron-based members, which is as small as aluminum alloy.

As described above, the cermet has its thermal conductivity, thermal expansion coefficient, and longitudinal elasticity by changing the material of the ceramic material and the material of the metal or metal alloy and the content ratio thereof. Characteristics such as coefficient and density can be adjusted.

For example, when the cermet was formed of ceramic and an aluminum alloy and the content of the aluminum alloy was changed to compare the characteristics, the results shown in FIG. 3 were obtained.

As can be seen from FIG. 3, when the content of the aluminum alloy is changed, all of the thermal conductivity, the coefficient of thermal expansion, the modulus of longitudinal elasticity, and the density of the cermet change. Therefore, cermet adjusts its properties such as thermal conductivity, thermal expansion coefficient, longitudinal elastic modulus and density by changing the ceramic material and metal or metal alloy material which are the constituent materials and their content ratio. By changing the composition of the ceramic itself, the characteristics of the cermet can be adjusted. As a cermet, the thermal conductivity is larger than that of the input pieces 11 and 12,
In addition, the upper mold 6 and the lower mold 7 are formed by fabricating one having a thermal expansion coefficient equal to or less than that of the input pieces 11 and 12.

Although not shown in FIG. 1, the resin molding apparatus 1 includes a gate, a sprue, a runner, and the like for filling the cavity 13 with resin.

Next, the operation of the present embodiment will be described. When molding the plastic resin, the resin molding apparatus 1 adjusts the temperature of the upper mold 6 and the lower mold 7 to a predetermined constant temperature by the heaters of the temperature adjusting units 8a and 8b or the refrigerant flow paths.
Mold temperature adjusting plates 5a, 5b Press arms 2a, 2b
Then, the upper mold 6 and the lower mold 7 are clamped via the die plates 3a and 3b, and then the resin is filled into the cavity 13 defined by the input pieces 11 and 12. When the resin is filled into the cavity 13, the resin molding apparatus 1 gradually cools the upper mold 6 and the lower mold 7 to a temperature not higher than the heat denaturation temperature of the resin, and presses the upper mold 6 and the lower mold 6 with the arms 2a and 2b of the press machine. Open the mold 7 and take out the resin molded product.

In molding this plastic resin,
The upper mold 6 and the lower mold 7 of the resin molding apparatus 1 are formed of a cermet, and the composition of the cermet forming the upper mold 6 and the lower mold 7 is appropriately selected to form the cermet. The thermal conductivity of the upper mold 6 and the lower mold 7 is changed to the insertion pieces 11 and 1 inserted in the upper mold 6 and the lower mold 7.
2 and the thermal expansion coefficient is equal to or less than the thermal expansion coefficient of the input pieces 11 and 12.

Therefore, since the upper mold 6 and the lower mold 7 have higher thermal conductivity than the input pieces 11 and 12, the temperature distribution generated in the upper mold 6 and the lower mold 7 during molding is reduced. And the molding quality of the plastic resin can be improved.

Since the thermal expansion coefficients of the upper mold 6 and the lower mold 7 are equal to or higher than the thermal expansion coefficients of the input pieces 11 and 12, the upper mold 6 and the lower mold 6 are formed by the internal pressure of the plastic resin during molding. The lower mold 7 can be prevented from being distorted, and the molding quality of the plastic resin can be improved.

Further, the cermet forming the upper mold 6 and the lower mold 7 has a specific gravity of 2.7 to 3.0, which is less than half that of an iron-based member, and is as small as an aluminum alloy. Therefore, handling is very easy.

In this embodiment, the upper mold 6
While the lower mold 7 is heated to a certain temperature, the molten resin is filled into the cavity 13 and then the resin is cooled and solidified. In this case, the upper mold 6 and the lower mold 7 Since the rate is large, cooling after filling the resin can be performed quickly, the molding cycle can be shortened, and the temperatures of the upper mold 6 and the lower mold 7 at the time of molding are made uniform, so that molding can be performed. Accuracy can be improved.

In the present embodiment, the temperature adjusting sections 8a and 8b are provided on the mold temperature adjusting plates 5a and 5b different from the upper mold 6 and the lower mold 7, but the upper mold 6 And the lower mold 7. In this case, after the upper mold 6 and the lower mold 7 are formed with an insertion hole for inserting a mold heating member or a mold cooling member constituting the temperature adjusting portions 8a and 8b by the casting method as described above, When the mold heating member or the mold cooling member is inserted into the insertion hole, a clearance is generated between the mold heating member or the mold cooling member and the wall surfaces of the insertion holes of the upper mold 6 and the lower mold 7. Then, a heat insulating layer of air is formed in the clearance. Accordingly, the thermal efficiency between the mold heating member or the mold cooling member, which is the temperature adjusting portions 8a and 8b, and the upper mold 6 and the lower mold 7 is deteriorated.
Temperature distribution is likely to occur in the upper mold 6 and the lower mold 7. If the clearance varies depending on the location due to the processing accuracy, the temperature distribution of the upper die 6 and the lower die 7 becomes large at the time of molding, and the precision of the molded product deteriorates.

Therefore, the temperature adjusting sections 8a and 8b are
And the lower mold 7, the upper mold 6 and the lower mold 7
Is cast into a desired mold, a mold heating member or a mold cooling member serving as the temperature adjusting portions 8a and 8b is simultaneously cast. In this way, the clearance between the mold heating member or the mold cooling member and the upper mold 6 and the lower mold 7 can be completely eliminated and can be brought into close contact with each other. The temperature distribution of the mold 7 can be made uniform, and the accuracy of the molded product can be improved. In addition, it is possible to improve the thermal conductivity between the mold heating member or the mold cooling member constituting the temperature adjustment units 8a and 8b and the upper mold 6 and the lower mold 7.
When raising or lowering the temperature of the upper mold 6 and the lower mold 7 by the mold heating member or the mold cooling member during molding, the heating rate and the cooling rate can be increased, and the molding cycle can be shortened. Can be.

In the above embodiment, the upper mold 6 and the lower mold 7 are formed by the casting method. However, the method of forming the upper mold 6 and the lower mold 7 is not limited to the casting method. is not. In particular, the cermet of the upper mold 6 and the lower mold 7 is
The lower the content of the metal or its alloy as the constituent material and the higher the content of the ceramic, the higher the stiffness. Even when the upper mold 6 and the lower mold 7 are provided with the temperature adjusting portions 8a and 8b, Although the rigidity of the temperature adjusting portions 8a and 8b increases, the fluidity of the ceramic decreases,
With the casting method, it is not possible to process with high accuracy.

In such a case, the molten metal or its alloy is infiltrated into the ceramic previously formed into the shape of the upper mold 6 and the lower mold 7 to form a cermet, thereby forming a cermet.
Then, the lower mold 7 is manufactured.

In this manner, the upper mold and the lower mold 7 having the intended thermal conductivity and thermal expansion coefficient can be formed easily and inexpensively, and a high-precision molded article can be formed at low cost. it can.

Further, in the above embodiment, the molten resin is charged into the cavity 13 while the upper mold 6 and the lower mold 7 are heated to a constant temperature, and then the resin is cooled and cooled.
After the resin is filled or inserted into the cavity 13, the upper mold 6 and the lower mold 7 are heated or cooled, or heated and cooled, so as to reduce the residual stress generated in the molded product. Thus, the accuracy of the molded product may be further improved.

For example, after processing a plastic base material into a substantially final shape by injection molding in advance, the plastic base material is inserted into the cavity 13, and then the plastic base material is heated to a temperature equal to or higher than the glass transition temperature of the plastic base material. After melting and generating the resin internal pressure, the mirror surface portion 9 and the mirror surface portion 10 of the input piece 11 and the input piece 12 constituting the cavity 13 may be transferred to the plastic base material by gradually cooling.

At this time, in the resin molding apparatus 1, since the upper mold 6 and the lower mold 7 are formed of a cermet having a large thermal conductivity, the heating rate and the cooling rate of the upper mold 6 and the lower mold 7 are changed. The molding cycle can be shortened, the molding cycle can be shortened, and the temperature distribution of the upper mold 6 and the lower mold 7 during heating and cooling becomes uniform, so that molding quality can be improved.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

In the above embodiment, the entire upper mold 6 and lower mold 7 are formed of cermet.
Only a part of the upper mold 6 and the lower mold 7 may be formed of cermet.

[0060]

According to the resin molding apparatus of the first aspect of the present invention, all of the upper mold and the lower mold, or a part thereof, has a heat conductivity having a mirror surface portion and a cavity. Since the thermal expansion coefficient is larger than the thermal conductivity of the input piece, and the thermal expansion coefficient is formed of a heat conductive member equal to or smaller than the thermal expansion rate of the input piece, The temperature distribution of the lower mold is made uniform, the distortion of the upper mold and the lower mold can be prevented, and highly accurate molded products without sink marks and internal stress can be formed. It is possible to reduce the length and suppress the generation of burrs during molding.

According to the resin molding apparatus of the second aspect of the invention, the cermet, which is a composite material of ceramic and metal or an alloy thereof, is used as the heat conducting member of the upper mold and the lower mold. By changing the composition of the ceramic or the content of the metal or its alloy, it is possible to form a heat conductive member having the intended thermal conductivity and thermal expansion coefficient, and it is possible to obtain a molded product with higher precision, The molding cycle can be shortened, the generation of burrs at the time of molding can be further suppressed, and the weight can be reduced and the handleability can be improved.

According to the resin molding apparatus of the third aspect of the present invention, the heat conductive member is formed by impregnating the molten metal or its alloy into the ceramic and then casting it into a mold formed into a desired shape. Since the cermet is formed from the cermet, a heat conductive member having the intended thermal conductivity and thermal expansion coefficient can be formed easily at low cost, and a high-precision molded product can be formed at low cost.

According to the resin molding apparatus of the fourth aspect of the present invention, the heat conductive member is formed by melting a metal or an alloy thereof into ceramic previously formed in the shape of the heat conductive member of the upper mold and the lower mold. Since the cermet is formed by infiltrating the cermet, the content of the metal or alloy constituting the cermet is low, and even when the fluidity is low, a heat conductive member having an appropriately intended shape is accurately formed. It is possible,
High-precision molded products can be molded.

According to the resin molding apparatus of the present invention, the heat conduction member has a mold heating means for heating the upper mold and the lower mold, or a mold for cooling the upper mold and the lower mold. Since the mold cooling means is embedded, the temperature of the upper mold and the lower mold can be changed efficiently by the mold heating means or the mold cooling means, and the molding cycle of the resin can be shortened. In addition, it is possible to further reduce the non-uniformity of the temperature distribution of the upper mold and the lower mold, and to mold a molded product with higher precision.

According to the resin molding apparatus of the present invention, after the upper mold and the lower mold are heated to a predetermined constant temperature,
Since the resin is filled and solidified to form the resin,
The molding cycle of the resin can be shortened, and the temperature uniformity of the upper mold and the lower mold during resin molding can be improved, so that the precision of the molded product can be further improved.

According to the resin molding apparatus of the present invention, after filling or inserting the resin into the cavity, the resin is molded by changing the temperature of the upper mold and the lower mold. The molding cycle of the resin can be shortened, and the temperature uniformity of the upper mold and the lower mold during resin molding can be improved, so that the precision of the molded product can be further improved.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a main part of a resin molding apparatus to which an embodiment of a resin molding apparatus according to the present invention is applied.

FIG. 2 is a view showing a comparison between characteristics of a cermet of SiC and an aluminum alloy and characteristics of an aluminum alloy, a copper alloy, and an iron-based member.

FIG. 3 is a diagram showing a change in characteristics when the aluminum content of a cermet of a ceramic and an aluminum alloy is changed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resin molding apparatus 2a, 2b Arm 3a, 3b Die plate 4a, 4b Heat insulation plate 5a, 5b Mold temperature adjustment plate 6 Upper mold 7 Lower mold 8a, 8b Temperature adjustment unit 9, 10 Mirror surface part 11, 12 Input piece 13 cavities

Claims (7)

[Claims] An upper mold and a lower mold are formed of members having predetermined thermal conductivity and thermal expansion coefficient, and at least one of the upper mold and the lower mold has a mirror surface portion. An input piece that defines a cavity is provided, and is a resin molding apparatus that molds a resin filled in the cavity, wherein the upper mold and the lower mold have all or part thereof. A part is formed of a heat conductive member whose thermal conductivity is larger than the thermal conductivity of the input piece, and whose thermal expansion coefficient is equal to or smaller than the thermal expansion rate of the input piece. A resin molding apparatus. 2. The resin molding apparatus according to claim 1, wherein the heat conducting members of the upper mold and the lower mold are cermets, which are composite materials of ceramic and metal or an alloy thereof. 3. The cermet according to claim 1, wherein the heat conducting member is a cermet formed by impregnating a molten metal or an alloy thereof into a ceramic, and then casting the molten metal or the alloy into a mold formed into a desired shape. The resin molding apparatus according to claim 1 or 2. 4. The heat conducting member is a cermet formed by infiltrating molten metal or an alloy thereof into ceramic previously formed in the shape of the heat conducting member of the upper mold and the lower mold. The resin molding apparatus according to claim 1 or 2, wherein 5. The heat conduction member includes a mold heating means for heating the upper mold and the lower mold, or a mold cooling means for cooling the upper mold and the lower mold. The resin molding apparatus according to any one of claims 1 to 3, wherein: 6. The resin molding apparatus heats the upper mold and the lower mold to a predetermined constant temperature, and then fills and solidifies the resin to mold the resin. The resin molding device according to claim 1. 7. The resin molding apparatus is characterized in that after filling or inserting the resin into the cavity, the resin is molded by changing the temperature of the upper mold and the lower mold. The resin molding device according to claim 1.