JP2815839B2 - Precision molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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 apparatus for producing a large amount of products requiring precision, such as a plastic lens, etc., as disclosed in JP-A-3-33494, JP-A-3-132323, and JP-A-3-132323. -54608, JP-A-4-163119,
It has been proposed as JP-A-4-310717, JP-A-5-162139, and the like.

[0003] Such a precision molding apparatus has a pair of dies which are integrally joined to form one cavity, and the cavity is formed into a shape corresponding to a product to be molded. A pair of die plates on which such a pair of dies are individually mounted are movably supported in the contact and separation directions at positions facing each other, for example, a heating mechanism for heating the dies and a cooling mechanism for cooling. Is provided.

In a precision molding apparatus having such a structure, a pair of dies are integrally joined by a pair of die plates to form one cavity, and a resin is injected into the cavity to precisely mold a product. At this time, the mold is first heated by a heating mechanism to generate an internal pressure in the resin, and then the mold is cooled by a cooling mechanism such as a heat pipe to transfer the transfer surface. In the apparatus of Japanese Patent Application Laid-Open No. 5-162139, the resin base material is processed in advance to a substantially final shape by another molding apparatus,
This resin base material is loaded into a precision molding device, heated, and then cooled to finish-mold into a more precise shape.

In controlling the temperature of the mold as described above, if the temperature of the cavity does not change uniformly, the molding accuracy is reduced. Therefore, in the precision molding apparatus disclosed in Japanese Patent Application Laid-Open No. 5-162139, Formed of copper alloy or aluminum alloy with high rate,
The mold has a built-in rod heater as a heating mechanism and an opening for a cooling mechanism. In such a precision molding apparatus, since a heating mechanism and a cooling mechanism are provided in a mold having a high thermal conductivity, the temperature of the product to be molded can be controlled uniformly, and the molding accuracy and the production speed of the product can be controlled. And can be improved together.

[0006]

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

However, copper alloys and aluminum alloys having good thermal conductivity have low hardness, so that it is difficult to maintain the precision of the cavity, and the pressure at the time of molding deforms the mold, thereby lowering the precision of the product. It's easy to do. Also, in precision molding equipment, the mold is formed exclusively for each product and used after replacement.
If the heating mechanism and the cooling mechanism are provided directly on the mold, it is necessary to perform piping of 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 various types of molds requires complicated work and increases the number of parts of the entire system.

In order to solve the above-mentioned problems, it is conceivable that the heating mechanism and the cooling mechanism are formed separately from the mold, and are formed of a material having high hardness. However, in this case, the heating mechanism and the cooling mechanism have different molds and materials, so that the thermal expansion during heating of the heating mechanism and the thermal expansion of the mold are different, and the heat shrinkage during cooling of the cooling mechanism and the mold are different. Is also different from the heat shrinkage.
For this reason, when the heating mechanism and the cooling mechanism control the temperature of the mold, stress acts on the mold due to the difference in the amount of thermal expansion and the amount of heat shrinkage, and the cavity is deformed to cause molding failure.

[0009]

[0010]

According to the first aspect of the present invention,
It has a pair of dies that are integrally joined to form one cavity, and these pair of dies are supported by the die support mechanism so as to be movable in the contact and separation directions at opposing positions to heat the temperature control member. In a precision molding apparatus for heating the mold by a mechanism, the temperature control member is connected to the die and the die plate.
And a die plate was formed from a material having a higher hardness than the mold, and the mold was joined to the die plate . Therefore, when a pair of molds supported movably in the contact and separation directions by the mold support mechanism are integrally joined,
These pairs of molds form one cavity. When a product is precisely molded by the cavity, the mold is heated by the heating mechanism of the temperature control member. Since the mold is bonded to the die plate formed of a material with high hardness, for example, even if the mold is formed of a copper alloy or aluminum alloy having good thermal conductivity but low hardness, Cavity accuracy is maintained against pressure.

According to the second aspect of the present invention, in the first aspect, the temperature control member is disposed between the mold and the die plate and is separated into a plurality of temperature control blocks. Even if the temperature control member undergoes thermal contraction due to a change in temperature, this thermal contraction is absorbed by the gap between the temperature control blocks, and no unnecessary stress acts on the mold.

According to a third aspect of the present invention, there is provided a pair of dies which are integrally joined to form a single cavity, and a pair of die plates on which the pair of dies are individually mounted face each other. In a precision molding apparatus that is movably supported in the contact and separation directions and heats the mold by a heating mechanism of a temperature control member, the temperature control member is positioned between the mold and the die plate, 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 a pair of die plates movably in the contact and separation directions are integrally joined, the pair of dies form one cavity. When a product is precisely molded by the 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 formed of a copper alloy or aluminum alloy having good thermal conductivity but low hardness, the cavity can be formed against the pressure during molding. Accuracy is maintained. Since the temperature control member is located between the mold and the die plate, and the heat conductivity of the temperature control member is higher than the heat conductivity of the die plate, the heat generated by the heating mechanism of the temperature control member is good for the die plate. Without being conducted to the mold.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the temperature control member is divided into a plurality of temperature control blocks. The heat shrinkage is absorbed in the gap of the temperature control block, and no unnecessary stress acts on the mold.

According to the fifth aspect of the present invention, there is provided the second aspect of the present invention.
In the invention described in Item 4 , since the temperature control blocks are arranged at intervals that do not abut each other due to thermal expansion due to the molding temperature, a plurality of sequentially arranged temperature control members abut during molding to generate stress. There is no.

According to the sixth aspect of the present invention, the second aspect or the second aspect
In the invention described in Item 4 , since the temperature control block is separated at a position that does not overlap with the cavity in the direction in which the mold is brought into contact with or separated from the mold, deformation of the cavity due to the internal molding pressure can be prevented.

In the invention according to claim 7 , 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.

According to the eighth aspect of the present invention, a pair of dies individually mounted are integrally joined by a pair of die plates supported movably in contact and separation directions at opposing positions to form one cavity. When a product is precisely molded by the 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 and forms an interval that does not interact with each other, the mold is formed by combining 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 and contraction generated by heating and cooling does not act on the mold, and the mold does not deform.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. First, as shown in FIG. 1, a precision molding apparatus 1 exemplified here has a pair of die plates 2 serving as deformation preventing members.
Is a mold support mechanism (not shown) composed of a hydraulic press machine or the like
Thereby, it is supported movably in the approaching / separating direction at opposing positions. Since a pair of temperature control members 3 are individually mounted on opposing inner surfaces of the pair of die plates 2, the temperature control members 3 are mounted on the mold supporting mechanism via the die plate 2. Have been.

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 or the like, which is a material having high thermal conductivity, and have a rod-shaped heater 5 serving as a heating mechanism, a cooling mechanism, And a heat pipe 6. As shown in FIG. 2, the temperature control member 3 has one outer frame 7 as a support member, and the five temperature control blocks 4 are fixed to the outer frame 7 by bolts 8. , Are formed in a flat plate shape as a whole.

As shown in FIG. 1, a pair of dies 9 and 10 are individually mounted on opposing inner surfaces of the pair of temperature control members 3, and these dies 9 and 10 are integrated. Are formed, two cavities 11 are formed. The inner 12 which is a portion communicating from the cavity 11 to the temperature control member 3 is formed of an aluminum alloy or the like which is a material having a high thermal conductivity, and the outer 13 which 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. The hardness of the die plate 2 is higher than the hardness of the dies 9 and 10, but the heat conductivity is lower than the heat conductivity of the temperature control member 3. .

The temperature control member 3 includes one outer frame 7.
The five temperature control blocks 4 are fixed to
These are arranged at predetermined intervals in parallel with the joining surfaces of the dies 9 and 10. More specifically, they are arranged at intervals that do not abut each other due to thermal expansion due to the molding temperature, and are separated at positions that do not overlap with the cavities 11 in the direction in which the dies 9 and 10 come and go. Furthermore, since the cavities 11 are arranged symmetrically with respect to the center line, the cavities 11 are formed in a shape in which no stress acts on the dies 9 and 10 due to thermal expansion and thermal contraction.

In such a configuration, the precision molding device 1
Is connected to one end of the molds 9 and 10 mounted on the die plate 2 by a mold support mechanism and pressurized, and the molds 9 and 10 are
A resin is injected into the cavity 11 to precisely mold a plastic lens. At this time, the molds 9 and 10 are first heated by the heater 5 of the temperature control member 3 to generate internal pressure in the resin, and then the molds 9 and 10 are cooled by the heat pipe 6 to transfer the transfer surface. In addition, plastic lenses can be produced at high speed with good accuracy.

The above-described precision molding apparatus 1 comprises the dies 9, 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. For this reason, the number of parts of the entire system is reduced, and there is no need to perform piping and 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 the plurality of temperature control blocks 4 are provided, the mold 9,
The temperature of the ten cavities 11 can be uniformly controlled. Further, the cavities 11 of such dies 9 and 10
Are formed of an aluminum alloy or a copper alloy having a high thermal conductivity, so that the temperature of the cavity 11 can be favorably controlled by the temperature control member 3. On the other hand, since the outer 13 around the molds 9 and 10 is formed of a ferrous alloy having high hardness, the cavity 11 is not deformed by the pressure during molding, and the product can be molded with good precision. it can.

In particular, since the dies 9 and 10 are mounted on the high-hardness die plate 2, even if the dies 9 and 10 are integrally joined by these die plates 2 and pressed, the molding is performed. The cavity 11 is not deformed by the pressure at that time. In addition, since the die plate 2 has a lower thermal conductivity than the dies 9 and 10, the heat generated by the temperature control member 3 is not transmitted to the die plate 2 satisfactorily and is good for the dies 9 and 10. The temperature of the molds 9 and 10 is controlled by the temperature control member 3 with high efficiency.

Further, the outer 13 around the molds 9 and 10 is provided.
Since the materials of the temperature control member 3 and the temperature control member 3 are different from each other, 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 support the dies 9 and 10 They are arranged parallel to the joining surfaces of the dies 9 and 10. The dies 9 and 1 are arranged at intervals that do not abut 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.
No stress is applied to zero. Therefore, the temperature change of the temperature control member 3 causes the cavities 11 of the molds 9 and 10 to change.
Can be molded with good precision without deformation.

In addition, as described above, there are a plurality of temperature control blocks 4 for supporting the dies 9, 10, but this separation is performed at a position where the cavities 11 do not overlap with the dies 9, 10 in the direction of contact. Therefore, the pressure of the die plate 2 is well transmitted to the dies 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. In addition, since the plurality of temperature control blocks 4 are fixed to one outer frame 7 as described above, they can be handled as one temperature control member 3, and each of the temperature control blocks 4 is fixed at a predetermined position. , The dies 9 and 10 can be supported with good positional accuracy.

In this embodiment, various types of dies 9,
Although it is assumed that one type of temperature control member 3 is provided in the precision molding apparatus 1 in which the mold 10 is replaced, if the shape and the temperature distribution of the mold to be replaced are largely different, the temperature of the corresponding shape is changed. Preferably, a control member is provided. Even in such a case, for example, three types of temperature control members may be provided for thirty types of molds, so that the number of parts of the entire system can be reduced, and piping and wiring of the temperature control members can be reduced. Work load is also reduced.

In the precision molding apparatus 1 described above, the example in which the plurality of temperature control blocks 4 are fixed to the single outer frame 7 serving as a support member with the bolts 8 has been described, but the present invention is not limited to the above-described method. As shown in FIG. 3, it is also 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]

[0032]

According to the first aspect of the present invention, a die plate is formed of a material having a hardness higher than that of a mold, and
Maintained by bonding the mold bets, for example, be a mold formed by thermal conductivity is good hardness lower copper alloy or aluminum alloy, the cavity of accuracy against the pressure in the molding Therefore, the product can be molded with good accuracy.

According to the second aspect of the present invention, the temperature control member is disposed between the mold and the die plate, and is separated into a plurality of temperature control blocks. Even if heat shrinks, this heat shrinkage is absorbed in the gap of the temperature control block and no unnecessary stress acts on the mold, so that it is possible to prevent the cavity from being deformed due to the stress acting on the mold, thereby improving the product quality. It can be molded with high precision.

According to a third aspect of the present invention, the temperature control member is located between the die and the die plate, the hardness of the die plate is higher than the hardness of the die, and the thermal conductivity of the temperature control member is lower than that of the die plate. By having a higher thermal conductivity, for example, even if the mold is formed of a copper alloy or aluminum alloy that has good thermal conductivity but low hardness, the precision of the cavity is maintained against the pressure during molding. Since the product can be molded with good accuracy, the heat generated by the heating mechanism of the temperature control member is well transmitted to the die without being well transmitted to the die plate. Can be efficiently controlled by the temperature control member.

According to the fourth aspect of the present invention, since the temperature control member is separated into a plurality of temperature control blocks, even if the temperature control member thermally contracts due to a change in temperature, the thermal contraction is prevented by the temperature control block. Since unnecessary stress does not act on the mold due to absorption in the gap, it is possible to prevent the cavity from being deformed due to stress acting on the mold, and it is possible to mold the product with good precision.

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

According to the sixth aspect of the present invention, the temperature control block is separated at a position where the temperature control block does not overlap with the cavity in the direction of contacting and separating the mold, so that the pressure of the die plate is applied to the cavity of the mold by the temperature control member. The cavity can be prevented from deforming due to the internal pressure of the cavity during molding, and the product can be molded with good precision.

According to the seventh aspect of the present 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 member is moved to a predetermined position. Can be fixedly arranged.

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

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing a precision molding apparatus 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 modification of the temperature control member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Precision molding apparatus 2 Deformation prevention member, die plate 3 Temperature control member 4 Temperature control block 5 Heating mechanism 6 Cooling mechanism 9,10 Mold 11 Cavity

Continuation of the front page (72) Inventor Hidenobu Kishi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (56) References JP 6-73888 (JP, B2) (58) Fields surveyed (Int.Cl. ⁶ , DB name) B29C 33 / 02,45 / 26

Claims (8)

(57) [Claims] 1. A pair of dies which are integrally joined to form one cavity, and these dies are individually mounted.
Wear is the movably supported to and away direction by a pair of die plates facing each position, the precision molding device for heating the mold by the heating mechanism of the temperature control member, said temperature system
The control member is located between the mold and the die plate.
And a die plate formed of a material having a higher hardness than the die , and the die is bonded to the die plate . 2. A temperature control member is disposed between the die and the die plate, precision molding apparatus according to claim 1, wherein it is separated into a plurality of temperature control block. 3. A pair of dies which are integrally joined to form one cavity, and a pair of die plates to which the pair of dies are individually mounted are moved in opposing positions at opposing positions. 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. A precision molding apparatus having a hardness higher than a mold hardness and a thermal conductivity of the temperature control member being higher than a thermal conductivity of the die plate. 4. The precision molding apparatus according to claim 3 , wherein the temperature control member is divided into a plurality of temperature control blocks. 5. The precision molding apparatus according to claim 2 , wherein the temperature control blocks are arranged at intervals that do not abut each other due to thermal expansion due to molding temperature. 6. The precision molding apparatus according to claim 2 , wherein the temperature control block is separated at a position where the temperature control block does not overlap with the cavity in the direction of approaching and separating the mold. 7. The temperature control block according to claim 2 , wherein a plurality of temperature control blocks are fixed to one support member.
The precision molding device as described. 8. A pair of dies that are integrally joined to form one cavity, and a pair of die plates to which the pair of dies are individually mounted are moved in opposing positions at opposing positions. In a precision molding apparatus having a heating mechanism for heating the mold and a cooling mechanism for cooling the mold, the heating mechanism and the cooling mechanism are provided on a temperature control member, and the temperature control member is provided on the mold. And between the die plate
A precision molding apparatus, wherein a gap is formed in which the temperature control member is divided into a plurality of parts and a stress due to thermal expansion or thermal contraction does not act on the mold.