JPH081679A - Production of resin mold - Google Patents

Abstract

PURPOSE:To produce a high precision resin mold by arranging temp. control pipes to shape fundamental matter and a shape reversal produced article in respective shape reversal processes and allowing a temp.-control medium to flow at the time of casting to control a resin to constant temp. CONSTITUTION:Temp. control pipes 6c, 6d are arranged to a master, a primary reversal mold and a secondary reversal mold 12 becoming shape fundamental matters in respective processes, that is, a process producing a primary reversal mold from a master, a process producing a secondary reversal mold 12 from the primary reversal mold and a process producing a resin mold from the secondary reversal mold 12 and a primary reversal mold, a secondary reversal mold and a resin mold being produced articles and temp. control is performed to stabilize a production state even when there is irregularity in the temp. of a production place or the heat generating temp. at the time of the mixing of a material. When the temp. control pipe 6c is detached after the curing of a casting material is completed, respective shape fundamental matters become a state having flexibility and can be easily bent and the shape fundamental matters and the produced articles can be demolded without being damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin mold manufacturing method, and more particularly to a method of manufacturing a highly accurate resin mold.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a resin mold, a prototype made of plastic, wood, metal or the like is used, and the prototype is fixed and held in a mold, and an epoxy resin or the like is put in the mold. The resin mold material was injected and cured, and after curing, the master mold was released.

However, in this method, if the prototype is made of a hard material and the shape is complicated, or if the draft is small, it is difficult to remove the mold, and the resin mold or the prototype is often damaged. .

As a method of manufacturing a resin mold that solves the problem of demolding, as described in JP-A-2-22014, a prototype is fixed and held in a mold, and a rubber material is placed in the mold. Is injected and cured to make a rubber-made primary inversion mold, and then this primary inversion mold is fixed and held in a mold, and a rubber material is injected into this mold and cured to make a new rubber mold. A method of producing a secondary inversion mold, further fixing and holding the secondary inversion mold in a mold, injecting a resin mold material into the mold and curing the resin mold to manufacture a resin mold is used. .

In this method, since a polysulfide rubber for casting is used as the material of the first inversion type and a material having excellent flexibility such as silicone rubber is used as the material of the second inversion type.
Good releasability, and it is possible to prevent destruction of the resin mold or the original mold at the time of demolding as described above.

[0006]

In the above-mentioned prior art, sufficient consideration has not been given to the dimensional accuracy of the resin mold.

In the method of casting a resin mold directly from the master mold, when the master mold is flexible and has a simple shape, it is possible to remove the master mold and the resin mold without damaging them. . However, the original mold is deformed by the weight of the material for the resin mold, the deformed shape is transferred, and a resin mold having a distorted shape is manufactured.

On the other hand, in the method of manufacturing a resin mold from the master through the first-order inversion type and the second-order inversion type, the master-to-first inversion type, the first-order inversion type to the second-order inversion type, and the second-order inversion type. There is a process of reversing the shape by casting three times from
A dimensional change in shape occurs in each process. Therefore, in order to obtain a highly accurate resin mold, it is necessary to stabilize the dimensional change in each process and correct the dimensions of the original mold in consideration of the dimensional change.

However, the flexibility, which is a characteristic of the first-order reversal type and second-order reversal type materials used here, is that it is easily deformed, which causes a deterioration in accuracy. When the secondary inversion type is produced from the primary inversion type, the primary inversion type is deformed by the weight of the material for the secondary inversion type, the deformed shape is transferred, and the distorted shape of the secondary inversion type is obtained. It is made. Similarly, when a resin mold is manufactured from the secondary reversal mold, the secondary reversal mold is deformed by the weight of the resin mold material and the injection pressure, and the deformed shape is transferred to produce a resin mold having a distorted shape. To be done.

The deformation in each of these steps is not constant but often varies. That is, there is a large difference in the finished dimensions of a plurality of primary reversal molds produced using the same prototype. The same phenomenon occurs in a plurality of secondary inversion types manufactured by using the same primary inversion type and a plurality of resin types manufactured by using the same secondary inversion type. Therefore, it is difficult to predict a dimensional change, and it is not easy to obtain a resin mold having a predetermined size by manufacturing once in consideration of the dimensional change from the beginning. In addition, even if the manufacturing process is performed once and the dimension of the prototype is corrected using the result of the dimension change, the deformation is not stable, so that the predetermined dimension may not be obtained even when the manufacturing process is performed next.

This is because the manufacturing conditions are not stable in each reversal process, such as a change in the temperature of the manufacturing place and a heat generation when the casting material is hardened depending on the mixing cost of the materials.

Therefore, there is a problem in that the resin mold has poor dimensional accuracy, and the dimensional accuracy of the molded product also becomes poor.

An object of the present invention is to solve the above conventional problems and provide a highly accurate resin mold.

Further, since the resin type material has a smaller thermal conductivity than metal, when the molding is performed using this material, the cooling efficiency of the molded molten resin is poor, the molding time becomes long, and the production capacity is increased. There is also a problem in that the cost of the molded product increases as the size becomes smaller.

Another object of the present invention is to provide a highly accurate resin mold which can solve this problem.

[0016]

In order to achieve the above object, in the present invention, in each shape reversing step, a basic object of a shape (a master or a master fixing jig for fixing the master,
A temperature control tube is placed on the first-order reversal type, second-order reversal type) and shape reversal products (first-order reversal type, second-order reversal type, resin type), and the temperature control medium is flowed during casting to control at a constant temperature. I decided to do it.

A method for producing a resin mold from a master through a primary inversion type and a secondary inversion type, 1) a secondary inversion type cast in the step of producing a secondary inversion type from a primary inversion type After the material is hardened, the temperature control tube placed in the primary inversion type is removed from the primary inversion type, and then the secondary inversion type is removed from the primary inversion type, and 2) the secondary inversion type is changed to the resin type. In the manufacturing process, after the cast resin mold material is cured, the temperature control tube placed in the secondary inversion mold is removed from the secondary inversion mold, and then the resin mold is
The mold was removed from the next inversion type.

Further, the temperature control tube arranged in the above resin mold is used as a cooling flow path during molding.

[0019]

Function: A basic object of a shape is formed in each step of a step of producing a primary inversion type from an original die, a step of producing a secondary inversion type from a primary inversion type, and a step of producing a resin die from a secondary inversion type. By arranging temperature control tubes on the prototype, the first inversion type, the second inversion type, and the manufactured first inversion type, the second inversion type, and the resin type, and controlling the temperature, the temperature of the manufacturing place and the material It is possible to stabilize the production state even if there is a variation in heat generation temperature during mixing.

If a temperature control tube made of a strong material such as metal is used, even if it is a flexible primary reversal type or secondary reversal type, it is inserted. In addition, the rigidity becomes higher, and even if the casting material is injected, the weight of the material and the deformation due to the injection pressure can be reduced. The object becomes flexible, can be easily bent, and can be demolded without damaging the shape basic object and the product.

Therefore, a highly accurate resin mold can be manufactured without damaging the original mold and the resin mold.

Further, by utilizing the temperature control tube arranged in the resin mold as a cooling flow path at the time of molding, it becomes possible to cool the portion close to the cavity surface, the cooling efficiency is improved, and the molding time is improved. Can be shortened, the production capacity can be improved, and the cost of the molded product can be reduced.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the resin mold manufacturing method of the present invention will be described below with reference to FIGS.

FIG. 1 is a view showing an embodiment in which a primary reversal mold is cast from a master mold according to the present invention. 1a, 1b,
1c and 1d are molds for determining the size of the primary inversion mold to be manufactured, 2 is an injection port for injecting the primary inversion mold material into the mold 1, 3
Is a prototype, 4 is a jig for fixing the prototype which positions, fixes and holds the prototype, 5 is a casting space surrounded by the mold 1, the prototype 3, and the prototype fixing jig 4, and 6a and 6b are the prototype fixing Jig 4
Among them, a temperature control pipe arranged in the casting space 5, 7a and 7b are pipes connected to the temperature control pipes 6a and 6b, and 8a and 8b are mold temperature controllers connected to the pipes 7a and 7b, respectively. , 9a,
9b is a temperature sensor arranged in the prototype fixing jig 4 and 10a and 10b are temperature sensors 9a and 10b, respectively.
9b is a wiring connecting the mold temperature controllers 8a and 8b.

With such an arrangement, the mold temperature controller 8
Each of a and 8b is set to a predetermined temperature. Then, the temperature control medium having a predetermined temperature is discharged from the mold temperature controllers 8a and 8b, respectively, and the temperature control tube 6a and the casting space 5 arranged in the prototype fixing jig 4 are passed through the pipes 7a and 7b. It flows through the temperature control tube 6b arranged in the above, and is returned to the mold temperature controllers 8a and 8b again.

Then, the main component of the material for the primary reversal type such as casting polysulfide rubber and the curing agent are mixed, and the mixture is injected from the injection port 2 to the mold 1
It is poured into the casting space 5a therein. Until the injected material for the primary inversion type is hardened, the temperature of the primary inversion type material injected into the prototype fixing jig 4 and the casting space 5 is measured by the temperature sensors 9a and 9b, and the wirings 10a and 10b are used. It is transmitted to the mold temperature controllers 8a and 8b.

In the mold temperature controllers 8a and 8b, the temperature of the temperature control medium is adjusted so that the measured temperatures of the primary fixing material 4 injected into the prototype fixing jig 4 and the casting space 5 become predetermined temperatures. Control up and down.

When the curing is completed, the mold 1 is removed, and the cured primary reversal mold is removed from the prototype 3 and the prototype fixing jig 4. As a result, the primary inversion type is manufactured.

In the above steps, since the temperatures of the primary reversal type and the original type are constantly controlled, the outside air temperature changes,
Since the production state can be made as desired regardless of the reaction heat generated when the material for the primary inversion type is cured, the primary inversion type having stable dimensions was always obtained.

In this embodiment, the temperature control tube 6a and the temperature sensor 9a are arranged in the prototype fixing jig 4, but the prototype 3
If it is sufficiently large, it can be placed in the prototype 3. It may be arranged on both the prototype 3 and the prototype fixing jig 4.

FIG. 2 is a view showing an embodiment of casting the first-order inversion type to the second-order inversion type according to the present invention. The structure is almost the same as in FIG. Reference numeral 11 is a first-order inversion type.

As in FIG. 1, mold temperature controllers 8b and 8c.
The material for the secondary inversion type, which has been injected into the primary inversion type 11 and the casting space 5b, is controlled to a predetermined temperature until the secondary inversion type material is cured. A flexible material such as silicone rubber is used as the secondary reversal type material.

Therefore, since the temperatures of the secondary inversion type and the primary inversion type are constantly controlled, the temperature of the outside air does not change, and the reaction heat generated when the material for the secondary inversion type is hardened does not depend on the reaction heat. Since the manufacturing conditions can be made as desired, the secondary reversal type having stable dimensions was always obtained.

Here, the primary reversal mold 11 is made of a flexible material such as casting polysulfide rubber, but the temperature control tube 6b made of a material having high strength such as metal is provided inside. By being arranged, it has rigidity and is difficult to deform.
Therefore, the deformation of the primary inversion type 11 due to the weight of the secondary inversion type material and the material injection pressure was small, and a highly accurate secondary inversion type was produced.

Further, after the secondary reversal type material is cured,
The mold 1 is removed, and then the temperature control tube 6b in the primary reversing mold 11 is removed from the primary reversing mold 11. Then, since the primary reversal type 11 is made of a flexible material,
It could be easily bent, and both the primary inversion type and the secondary inversion type could be released from the mold without damage.

FIG. 3 is a view showing an embodiment in which a resin mold is cast from a secondary reversal mold according to the present invention. The structure is almost the same as in FIGS. 12 is a first-order inversion type.

As in FIGS. 1 and 2, the mold temperature controller 8 is used.
The resin mold material injected into the secondary inversion mold 12 and the casting space 5c at c and 8d is controlled to a predetermined temperature until the resin mold material is cured.

Therefore, since the temperatures of the resin type and the secondary reversal type are constantly controlled, the outside air temperature changes,
Since the production state can be made as desired regardless of the reaction heat generated when the resin mold material is cured, a resin mold having a stable dimension was always obtained.

Here, the secondary reversal type 12 is made of a flexible material such as silicone rubber, but the temperature control tube 6c made of a material having high strength such as metal is arranged inside. Therefore, it has rigidity and is less likely to be deformed. Therefore, the deformation of the secondary reversal mold 12 due to the weight of the resin mold material and the material injection pressure was small, and a highly accurate resin mold was produced.

After the resin mold material has hardened, the mold 1 is removed, and then the temperature control tube 6c in the secondary reversal mold 12 is removed from the secondary reversal mold 12. Since the secondary reversal mold 12 is made of a flexible material, it can be easily bent,
Both were able to be removed from the mold without damaging the secondary reversal type and the resin type.

By the above manufacturing method, it is possible to manufacture a highly accurate resin mold which is always stable in size and has a small deformation.

Further, since the temperature control tube 6d is disposed in the manufactured resin mold, the cooling efficiency is improved by using the temperature control tube 6d at the time of molding and flowing the cooling medium, and the thermal conductivity is significantly smaller than that of metal. Even with a mold, the molding time was not extended, the production capacity could be improved, and the cost of the molded product could be reduced.

If the master 3 is flexible, it is possible to manufacture a highly accurate resin mold by directly injecting the resin mold material in the embodiment shown in FIG.

In the embodiment shown in FIGS. 1 to 3, even if the temperature controlled by the mold temperature controllers 8a, 8b, 8c, 8d is a constant temperature, the temperature control is a pattern that changes with time. Either can be used. Further, the respective temperatures may be the same or different. Further, in this embodiment, the temperature adjusting tubes 6a and 6b are arranged in the prototype fixing jig 4 and the casting space 5a, and the temperature adjusting tubes 6b are arranged in the primary reversing mold 11 and the casting space 5b. 6c, a temperature control tube 6c arranged in the secondary reversing mold 12 and the casting space 5c
Separate mold temperature controllers are used for and 6d, but there is no problem even if they are controlled by one mold temperature controller.

As described above, the basic object of the shape (a prototype or a jig for fixing the prototype, a primary inversion type, a secondary inversion type) and a shape inversion product (a primary inversion type, a secondary inversion type, Since the temperature control pipe is placed in the resin mold and the temperature control medium is made to flow at the time of casting to control the temperature to a constant temperature, the manufacturing state can be stabilized, so the dimensions of the resin mold are stabilized. In addition, by arranging the temperature control tube, it has rigidity at the time of casting and it has flexibility by removing it at the time of demolding, so it is possible to prevent deformation at the time of casting, and it is highly accurate. The resin mold of

Further, the cooling efficiency can be improved by the temperature control tube arranged in the resin mold, the production capacity can be improved, and the cost of the molded product can be reduced.

[0047]

As described above, according to the present invention, the manufacturing state can be stabilized and the deformation at the time of casting can be prevented, so that a highly accurate resin mold can be provided. Further, since the cooling efficiency in the molding using this can be improved, the production capacity can be improved and the cost of the molded product can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a method for producing a primary inversion mold from a master mold according to the present invention.

FIG. 2 is a longitudinal sectional view showing an embodiment of a method for manufacturing a secondary inversion type from a primary inversion type according to the present invention.

FIG. 3 is a vertical cross-sectional view showing an embodiment of a method for manufacturing a resin mold from a secondary inversion mold according to the present invention.

[Explanation of symbols]

 1 ... Formwork, 2 ... Injection port, 3 ... Prototype, 4 ... Prototype fixing jig, 5 ... Casting space, 6 ... Temperature control pipe, 7 ... Piping, 8 ... Mold temperature controller, 9 ... Temperature Sensor, 10 ... Wiring, 11 ... Primary inversion type, 12 ... Secondary inversion type.

Claims (5)

[Claims] 1. A primary inversion type is produced from a prototype by casting,
Next, in a method of producing a secondary inversion type from the primary inversion type by casting, and further producing a resin mold from the secondary inversion type by casting, in the step of producing the primary inversion type from the master, A prototype fixing jig for fixing the inside or the prototype is equipped with a temperature control tube, the temperature control tube is arranged in a space for casting the first-order inversion type material, and the master for fixing the inside or the prototype at the time of casting A temperature control medium is caused to flow through a temperature control tube arranged in a fixing jig and a temperature control tube arranged in the casting space to control the temperatures of the prototype and the cast primary inversion material, When the casting material for the next reversal type is cured, the temperature control tube arranged in the casting space is arranged in the cured first reversal type, and the second reversal type is produced from the first reversal type. In the step of, the temperature control tube is provided in the primary inversion type, and the secondary inversion type material is cast. A temperature control tube is disposed between the temperature control tubes arranged in the first inversion mold and the temperature control tube arranged in the casting space at the time of casting, and the temperature control medium is flowed to the first inversion type and When the temperature of the cast secondary reversal type material is controlled and the casting material for the secondary reversal type is cured, a temperature control tube arranged in the casting space is arranged in the cured secondary reversal type material. In the process of manufacturing the resin mold from the secondary inversion mold, a temperature control pipe is provided in the secondary inversion mold, and the temperature control pipe is arranged in the space for casting the resin mold material. At the time of molding, a temperature control medium is caused to flow through the temperature control tube arranged in the secondary reversal mold and the temperature control tube arranged in the casting space to control the temperature of the secondary reversal mold and the cast resin mold material. Controlling, when the casting material for the resin mold is cured, the temperature control pipe arranged in the casting space is arranged in the cured resin mold. Resin type method for producing characterized in that. 2. The method according to claim 1, wherein in the step of producing the secondary inversion type from the primary inversion type, after the cast secondary inversion type material is cured, the temperature is set in the primary inversion type. In the process of removing the pipe from the primary inversion mold, then removing the secondary inversion mold from the primary inversion mold, and producing a resin mold from the secondary inversion mold, the cast resin mold material is After curing, the temperature control tube arranged in the secondary inversion mold is removed from the secondary inversion mold, and then the resin mold is released from the secondary inversion mold. 3. A primary inversion type is produced from a prototype by casting,
Next, a method of producing a secondary inversion type from the primary inversion type by casting, and further producing a resin type from the secondary inversion type by casting, in which the secondary inversion type is produced from the primary inversion type In the process of
The primary reversal mold has rigidity at the time of casting, and has flexibility at the time of demolding after casting, and in the step of manufacturing the resin mold from the secondary reversal mold, the secondary reversal mold is cast. A method for producing a resin mold, which has rigidity at the time of molding and has flexibility at the time of demolding after casting. 4. The primary inversion type according to claim 1, wherein the primary inversion type has rigidity due to the presence of a temperature control tube installed in the primary inversion type. By removing the temperature control tube installed in the secondary reversal mold from the primary reversal mold, the primary reversal mold becomes flexible, and there is the temperature control pipe installed in the secondary reversal mold. As a result, the secondary inversion type has rigidity, and by removing the temperature control pipe installed in the secondary inversion type from the primary inversion type, the secondary inversion type has flexibility. A method for producing a resin mold, comprising: 5. A method for producing a resin mold from a mold by casting, wherein a temperature adjusting tube is provided in the mold or a mold fixing jig for fixing the mold, and the temperature is adjusted in a space for casting the resin mold material. A pipe is arranged, and a temperature control medium is flown into the temperature control pipe arranged in the prototype or a mold fixing jig for fixing the prototype during casting and the temperature control pipe arranged in the casting space, and the prototype and A method for producing a resin mold, characterized in that the temperature of the cast resin mold material is controlled.