JPH0999437A - Precise molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the entire structure of a system for molding a resin product by a mold and to facilitate the handling. SOLUTION: A temperature control member 3 is provided at a mold supporting mechanism for separably supporting molds 9, 10 to eliminate the necessity of providing the member 3 at many types of the molds 9, 10 and to reduce the number of component parts by simplifying the structure of the entire system. Further, the necessity of piping the member 3 at each time of replacing the molds 9, 10 is eliminated as well, and the handling is facilitated.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a precision molding apparatus for precision molding a product such as a plastic lens.

[0002]

2. Description of the Related Art At present, there is a precision molding device as a device for producing a large amount of products such as plastic lenses that require high precision, which are disclosed in JP-A-3-33494, JP-A-3-132323 and JP-A-3-32. -54608 publication, JP-A-4-163119 publication,
It has been proposed as JP-A-4-310717, JP-A-5-162139 and the like.

Such a precision molding apparatus has a pair of molds which are integrally joined to form one cavity, and the cavity is formed in a shape corresponding to a product to be molded. A pair of die plates to which such a pair of dies are individually mounted are movably supported in the contact and separation directions at positions facing each other, and for example, a heating mechanism for heating the dies and a cooling mechanism for cooling the dies. Is provided.

In the precision molding apparatus having such a structure, a pair of molds are integrally joined by a pair of die plates to form one cavity, and a resin is injected into this cavity to precisely mold a product. At this time, first, the die is heated by a heating mechanism to generate an internal pressure in the resin, and then the die is cooled by a cooling mechanism such as a heat pipe to transfer the transfer surface. Incidentally, in the apparatus of JP-A-5-162139, the resin base material is processed into a substantially final shape in advance by another molding apparatus,
This resin base material is loaded into a precision molding device, heated, cooled, and finish-molded into a more precise shape.

When the temperature of the mold is controlled as described above, the molding accuracy decreases if the temperature of the cavity does not change uniformly. Therefore, in the precision molding apparatus of Japanese Patent Laid-Open No. 5-162139, the mold is heat-conducted. Made of copper alloy or aluminum alloy with high rate,
A bar heater, which is a heating mechanism, is built in this mold, and an air hole, which is a cooling mechanism, is opened. In such a precision molding apparatus, since the mold having high thermal conductivity is provided with the heating mechanism and the cooling mechanism, the temperature of the product to be molded can be uniformly controlled, and the molding accuracy and production speed of the product can be improved. And can be improved together.

[0006]

In the precision molding apparatus of Japanese Patent Laid-Open No. 5-162139, in order to improve both molding precision and production speed of a product, a mold having high thermal conductivity is provided with a heating mechanism and a cooling mechanism. Is provided.

However, since copper alloy and aluminum alloy having good thermal conductivity have low hardness, it is difficult to maintain the accuracy of the cavity, and the mold deforms due to the pressure at the time of molding and the accuracy of the product deteriorates. It's easy to do. Also, in precision molding equipment, the mold is formed exclusively for each product and is used by exchanging,
When the heating mechanism and the cooling mechanism are directly provided on the mold, it is necessary to perform piping for the heating mechanism and the cooling mechanism each time the mold is replaced. Further, providing a heating mechanism and a cooling mechanism in each of the various types of molds complicates the work and increases the number of parts in the entire system.

In order to solve the above problems, it is possible to envision that the heating mechanism and the cooling mechanism are formed separately from the mold and are made of a material having high hardness. However, in this case, since the heating mechanism and the cooling mechanism are different from each other in the mold and the material, the thermal expansion of the heating mechanism during heating and the thermal expansion of the mold are different, and the thermal contraction and the mold during cooling of the cooling mechanism are different. It is also different from the heat contraction.
Therefore, when the heating mechanism or the cooling mechanism controls the temperature of the mold, stress acts on the mold due to the difference in the amount of thermal expansion or the amount of thermal contraction, and the cavity is deformed to cause defective molding.

[0009]

According to the first aspect of the present invention,
It has a pair of molds that are joined together to form a cavity, and these molds are supported by a mold support mechanism so as to be movable in the contact and separation directions at opposite positions, and the temperature control member is heated. In a precision molding apparatus that heats the mold by a mechanism, the temperature control member is provided in the mold supporting mechanism. Therefore, when a pair of molds that are movably supported in the contacting / separating direction by the mold supporting mechanism are integrally joined, the pair of molds forms one cavity. When the product is precisely molded by this cavity, the mold is heated by the heating mechanism of the temperature control member. Since this temperature control member is mounted on the mold support mechanism, it is not necessary to provide a temperature control member for each of the various types of molds, and the structure of the entire system is simple and the number of parts is small. Further, it is not necessary to provide piping for the heating mechanism of the temperature control member every time the mold is replaced.

According to a second aspect of the present invention, there is provided a pair of molds which are integrally joined to each other to form one cavity, and the pair of molds are arranged in a contacting / separating direction at positions opposed to each other by a mold supporting mechanism. In a precision molding apparatus that movably supports and heats the mold by a heating mechanism of a temperature control member, a deformation preventing member is formed of a material having a hardness higher than that of the mold, and the mold is joined to the deformation preventing member. did. Therefore, when a pair of molds that are movably supported in the contacting / separating direction by the mold supporting mechanism are integrally joined, the pair of molds forms one cavity. When the product is precisely molded by this cavity, the mold is heated by the heating mechanism of the temperature control member. Since the mold is joined to the deformation prevention member formed of a material with high hardness, for example, even if the mold is formed of a copper alloy or aluminum alloy that has good thermal conductivity but low hardness, The accuracy of the cavity is maintained against the pressure of.

According to a third aspect of the invention, in the second aspect of the invention, the temperature control member is disposed between the mold and the deformation preventing member and is divided into a plurality of temperature control blocks. Even if the temperature control member undergoes thermal contraction due to temperature change, this thermal contraction is absorbed in the gap of the temperature control block, and unnecessary stress does not act on the mold.

According to a fourth aspect of the present invention, there is provided a pair of molds which are integrally joined to each other to form a cavity, and the pair of molds are individually mounted to a pair of die plates facing each other. In a precision molding apparatus in which the temperature control member is movably supported by a heating mechanism of a temperature control member, the temperature control member is located between the die and the die plate, and The hardness of the plate is higher than the hardness of the mold, and the thermal conductivity of the temperature control member is higher than the thermal conductivity of the die plate. Therefore, when a pair of dies individually supported by the pair of die plates so as to be movable in the contact and separation directions are integrally joined, the pair of dies form one cavity. When the product is precisely molded by this cavity, the mold is heated by the heating mechanism of the temperature control member. Since the hardness of the die plate is higher than the hardness of the mold, for example, even if the mold is made of a copper alloy or an aluminum alloy that has good thermal conductivity but low hardness, the cavity will resist the pressure during molding. Accuracy is maintained. Since the temperature control member is located between the die and the die plate, and the thermal conductivity of the temperature control member is higher than that of the die plate, the amount of heat generated by the heating mechanism of the temperature control member is good for the die plate. Good conduction to the mold without conduction to the mold.

According to the invention of claim 5, in the invention of claim 4, since the temperature control member is divided into a plurality of temperature control blocks, even if the temperature control member is thermally contracted due to temperature change, this The heat shrinkage is absorbed in the gap of the temperature control block so that unnecessary stress does not act on the mold.

According to a sixth aspect of the present invention, in the third or fifth aspect of the invention, the temperature control blocks are arranged at intervals so that they do not abut each other due to thermal expansion due to the molding temperature. The temperature control member does not come into contact with each other during molding to generate stress.

According to a seventh aspect of the invention, in the third or fifth aspect of the invention, the temperature control block is separated at a position that does not overlap the cavity in the die contacting / separating direction. Deformation can be prevented.

In the eighth aspect of the invention, since the plurality of temperature control blocks are fixed to one support member, the plurality of temperature control members can be handled as one part.

In a ninth aspect of the present invention, a pair of die plates that are individually mounted are integrally joined by a pair of die plates that are movably supported in the contact and separation directions at opposite positions to form one cavity. When the product is precisely formed by using this cavity, the temperature of the mold is controlled by heating the heating mechanism and cooling the cooling mechanism. Since such a temperature control member is separated into a plurality of spaces so as not to interact with each other, the mold is formed by a combination of a plurality of members (for example, a member having high thermal conductivity and a member having high hardness). Even if the temperature control member and the mold are made of different materials, stress due to thermal expansion or contraction generated by heating or cooling does not act on the mold and the mold is not deformed.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, as shown in FIG. 1, the precision molding apparatus 1 illustrated here has a pair of die plates 2 serving as deformation preventing members.
Is a mold support mechanism (not shown) including a hydraulic press machine, etc.
Thus, they are supported so as to be movable in the contact and separation directions at the positions facing each other. Since a pair of temperature control members 3 are individually mounted on the inner surfaces of the pair of die plates 2 that face each other, the temperature control members 3 are mounted on the mold support mechanism via the die plate 2. Has been done.

The temperature control member 3 is divided into five temperature control blocks 4 here. As shown in FIGS. 1 and 2, these temperature control blocks 4 are formed in a rectangular parallelepiped shape from an aluminum alloy, which is a material having high thermal conductivity, and have a rod-shaped heater 5 serving as a heating mechanism and a cooling mechanism. And the heat pipe 6 that is built in. As shown in FIG. 2, the temperature control member 3 has one outer frame 7 as a support member, and five temperature control blocks 4 are fixed to the outer frame 7 by bolts 8. , Is formed in a flat plate shape as a whole.

As shown in FIG. 1, a pair of molds 9 and 10 are individually mounted on the inner surfaces of the pair of temperature control members 3 facing each other, and these molds 9 and 10 are integrated. Two cavities 11 are formed when they are bonded to each other. The inner 12 that is a portion that communicates from the cavity 11 to the temperature control member 3 is formed of an aluminum alloy that is a material having a high thermal conductivity, and the outer 13 that is a peripheral portion has a high hardness. It is formed of a material such as an iron alloy.

The die plate 2 is made of, for example, an iron alloy, and its hardness is higher than that of the molds 9 and 10, but its thermal conductivity is lower than that of the temperature control member 3. .

The temperature control member 3 includes one outer frame 7
Five temperature control blocks 4 are fixed to
These are arranged at a predetermined interval in parallel with the joint surface of the molds 9 and 10. More specifically, they are arranged at intervals such that they do not come into contact with each other due to thermal expansion due to the molding temperature, and are separated at a position where they do not overlap with the cavity 11 in the contact and separation direction of the molds 9 and 10. Further, since the cavities 11 are arranged symmetrically with respect to the center line of the cavity 11, the cavities 11 are formed in a shape in which stress does not act on the molds 9 and 10 due to thermal expansion and contraction.

In such a structure, the precision molding device 1
Is joined to one end of the molds 9 and 10 mounted on the die plate 2 by the mold supporting mechanism and pressurizes the molds 9 and 10.
The resin is injected into the cavity 11 to precisely mold the plastic lens. At this time, first, the heaters 5 of the temperature control member 3 heat the molds 9 and 10 to generate internal pressure in the resin, and then the heat pipes 6 cool the molds 9 and 10 to transfer the transfer surface. The plastic lens can be produced at high speed with good accuracy.

The above-described precision molding apparatus 1 includes the molds 9 and 10.
Since the heater 5 and the heat pipe 6 for controlling the temperature are provided in the temperature control member 3, it is not necessary to provide the heater 5 and the heat pipe 6 in each of the molds 9 and 10 to be replaced for each product. Therefore, the number of parts of the entire system is reduced, and it is not necessary to perform piping or wiring every time the molds 9 and 10 are replaced.

Further, since the temperature control member 3 has the heater 5 and the heat pipe 6 built in each of the plurality of temperature control blocks 4, even if there are a plurality of temperature control blocks 4, the mold 9,
The temperature of the cavities 11 of 10 can be uniformly controlled. Further, the cavities 11 of the molds 9 and 10
Since the inner member 12 and the temperature control member 3 that form the above are both formed of an aluminum alloy or a copper alloy having high thermal conductivity, the temperature control member 3 can favorably control the temperature of the cavity 11. On the other hand, since the outer 13 around the molds 9 and 10 is formed of an iron alloy having high hardness, the cavity 11 is not deformed by the pressure during molding, and the product can be molded with good accuracy. it can.

Particularly, since the molds 9 and 10 as described above are mounted on the high hardness die plate 2, even if the molds 9 and 10 are integrally joined by the die plate 2 and pressed, the molding is performed. The cavity 11 will not be deformed by the pressure at the time. Moreover, since the die plate 2 has a lower thermal conductivity than the molds 9 and 10, the amount of heat generated by the temperature control member 3 is not well conducted to the die plate 2 and is good to the molds 9 and 10. The temperature of the molds 9 and 10 is highly efficiently controlled by the temperature control member 3.

Also, the outer 13 around the molds 9 and 10
Since the materials of the temperature control member 3 and the temperature control member 3 are different, the amounts of thermal expansion and thermal contraction are also different, but the plurality of temperature control blocks 4 of the temperature control member 3 that actually supports the molds 9 and 10 are The molds 9 and 10 are arranged parallel to the joint surface. The molds 9 and 1 are arranged at intervals such that they do not come into contact with each other due to thermal expansion due to the molding temperature, and are arranged symmetrically with respect to the center line of the cavity 11, due to thermal expansion and contraction.
No stress is applied to 0. Therefore, due to the temperature change of the temperature control member 3, the cavities 11 of the molds 9 and 10 are
The product can be molded with good accuracy without being deformed.

Moreover, as described above, there are a plurality of temperature control blocks 4 that support the molds 9 and 10. However, this separation is performed at a position where the molds 9 and 10 do not overlap with the cavity 11 in the contact and separation direction. Therefore, the pressure of the die plate 2 is satisfactorily transmitted to the molds 9 and 10 by the temperature control block 4,
Since the molds 9 and 10 are not deformed by the internal pressure of the cavity 11, the product can be molded with good accuracy. Moreover, since the plurality of temperature control blocks 4 are fixed to one outer frame 7 as described above, this can be handled as one temperature control member 3, and each of the temperature control blocks 4 is fixed at a predetermined position. Since they are arranged in a uniform manner, the molds 9 and 10 can be supported with good positional accuracy.

In this embodiment, various types of molds 9,
It is assumed that one type of temperature control member 3 is provided in the precision molding apparatus 1 for exchanging 10, but if the shape or temperature distribution of the die to be exchanged is largely different, the temperature of the shape corresponding to this It is preferable to provide a control member. Even in such a case, for example, since it is sufficient to provide three types of temperature control members for thirty types of molds, the number of parts of the entire system can be reduced, and the piping and wiring of the temperature control members can be reduced. Work load is also reduced.

In the above-mentioned precision molding apparatus 1, it has been illustrated that the plurality of temperature control blocks 4 are fixed to one outer frame 7 serving as a supporting member by the bolts 8, but the present invention is not limited to the above method. As shown in FIG. 3, it is possible to form the temperature control member 16 by fixing the temperature control block 4 to the beam 14 provided at the center of the outer frame 7 with bolts 15.

[0031]

According to the first aspect of the present invention, since the temperature control member is provided in the die support mechanism, it is not necessary to provide the temperature control member in each of the various types of dies, and therefore the structure of the entire system is improved. The number of parts can be simplified and the number of parts can be reduced, and it is possible to eliminate the need for piping for the heating mechanism of the temperature control member each time the mold is replaced.

According to the second aspect of the present invention, the deformation preventing member is formed of a material having a hardness higher than that of the mold, and the mold is joined to the deformation preventing member. For example, the mold has good thermal conductivity. However, even if it is formed of a copper alloy or an aluminum alloy having a low hardness, the accuracy of the cavity can be maintained against the pressure at the time of molding, so that the product can be molded with good accuracy.

According to the third aspect of the present invention, the temperature control member is disposed between the mold and the deformation preventing member and is divided into a plurality of temperature control blocks, so that the temperature control member changes in temperature. Even if heat shrinks, the heat shrinkage is absorbed in the gap of the temperature control block and unnecessary stress does not act on the mold, so it is possible to prevent stress from acting on the mold and deform the cavity. It can be molded with good accuracy.

According to a fourth aspect of the present invention, the temperature control member is located between the mold and the die plate, the hardness of the die plate is higher than the hardness of the mold, and the thermal conductivity of the temperature control member is that of the die plate. Higher than the thermal conductivity, for example, to maintain the accuracy of the cavity against the pressure during molding, even if the mold is made of copper alloy or aluminum alloy that has good thermal conductivity but low hardness. Therefore, the product can be molded with good accuracy, and the amount of heat generated by the heating mechanism of the temperature control member is not well conducted to the die plate but is well conducted to the die. The temperature can be controlled with high efficiency by the temperature control member.

According to the fifth aspect of the invention, the temperature control member is divided into a plurality of temperature control blocks, so that even if the temperature control member thermally contracts due to temperature change, this thermal contraction causes the temperature control block to contract. Since it is absorbed in the gap and unnecessary stress does not act on the die, it is possible to prevent the cavity from being deformed due to the stress on the die, and the product can be molded with good accuracy.

According to the sixth aspect of the present invention, the temperature control blocks are arranged at intervals such that they do not abut each other due to thermal expansion due to the molding temperature. Since they do not come into contact with each other due to expansion and generate stress in the mold, deformation of the cavity can be prevented and the product can be molded with good accuracy.

In the invention according to claim 7, the temperature control block is separated at a position which does not overlap with the cavity in the die contacting / separating direction, so that the pressure of the die plate is applied to the cavity of the die by the temperature control member. Therefore, the cavity can be prevented from being deformed by the internal pressure of the cavity during molding, and the product can be molded with good accuracy.

According to the eighth aspect of the invention, since the plurality of temperature control blocks are fixed to one support member, the plurality of temperature control members can be handled as one component, and the temperature control members can be positioned at predetermined positions. It can be fixedly arranged at.

According to the ninth aspect of the present invention, since the heating mechanism and the cooling mechanism are provided in the temperature control member, it is not necessary to provide the heating mechanism and the cooling mechanism in each of the molds to be replaced. In addition to reducing the number of parts, it is possible to eliminate the need for piping and wiring for the heating mechanism and cooling mechanism each time the mold is replaced.In addition, the temperature control member can be separated into multiple parts to reduce stress due to thermal expansion and contraction. By forming a gap that does not act on the mold, thermal expansion due to heating of the temperature control member and thermal contraction due to cooling do not act as stress on the mold, so that the cavity of the mold may be deformed during molding of the product. Therefore, the product can be molded with good accuracy.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a precision molding device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a temperature control member in which a plurality of temperature control members are fixed to an outer frame which is one support member.

FIG. 3 is a plan view showing a modified example of the temperature control member.

[Explanation of symbols]

 1 Precision Molding Equipment 2 Deformation Preventing Member, Die Plate 3 Temperature Control Member 4 Temperature Control Block 5 Heating Mechanism 6 Cooling Mechanism 9, 10 Mold 11 Cavity

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hidenobu Kishi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (9)

[Claims] 1. A pair of molds that are integrally joined to form one cavity, and the pair of molds are supported by a mold support mechanism so as to be movable in the contact and separation directions at positions facing each other. A precision molding apparatus for heating the mold by a heating mechanism of a temperature control member, wherein the temperature control member is provided in the mold supporting mechanism. 2. A pair of molds that are integrally joined to form one cavity, and the pair of molds are movably supported in a contacting and separating direction at positions facing each other by a mold supporting mechanism, In a precision molding apparatus for heating the mold by a heating mechanism of a temperature control member, a deformation preventing member is formed of a material having a hardness higher than that of the mold, and the mold is joined to the deformation preventing member. Precision molding equipment. 3. The precision molding apparatus according to claim 2, wherein the temperature control member is arranged between the mold and the deformation preventing member and is divided into a plurality of temperature control blocks. 4. A pair of molds that are integrally joined to form one cavity, and the pair of molds move in a contacting / separating direction at a position where a pair of die plates individually mounted are opposed to each other. In a precision molding apparatus that freely supports and heats the mold by a heating mechanism of a temperature control member, the temperature control member is located between the mold and the die plate, and the hardness of the die plate is the metal mold. The precision molding apparatus is characterized in that the hardness is higher than the mold hardness and the thermal conductivity of the temperature control member is higher than that of the die plate. 5. The precision molding apparatus according to claim 4, wherein the temperature control member is divided into a plurality of temperature control blocks. 6. The precision molding apparatus according to claim 3, wherein the temperature control blocks are arranged at intervals such that they do not abut each other due to thermal expansion due to molding temperature. 7. The precision molding apparatus according to claim 3, wherein the temperature control block is separated at a position which does not overlap with the cavity in the contact / separation direction of the mold. 8. The temperature control block according to claim 3, wherein the temperature control blocks are fixed to one support member.
Precision molding equipment described. 9. A pair of dies that are integrally joined to form one cavity, and the pair of dies move in a contacting / separating direction at a position where a pair of die plates individually mounted are opposed to each other. In a precision molding apparatus that freely supports and includes a heating mechanism that heats the mold and a cooling mechanism that cools the mold, the heating mechanism and the cooling mechanism are provided in a temperature control member, and the temperature control member is separated into a plurality of parts. A precision molding apparatus is characterized in that a gap is formed so that stress due to thermal expansion or thermal contraction does not act on the mold.