JPH06170967A - Ageing device - Google Patents

Abstract

PURPOSE:To provide an ageing device capable of uniformly and rapidly heating and cooling an ageing mold and capable of easily controlling the cooling speed of the ageing mold. CONSTITUTION:In an ageing device used in a plastic molded product manufacturing method wherein an injection process such that a plastic matrix is inserted in an ageing mold 1 to be heated to its glass transition point or higher to be melted and the molten matrix is gradually cooled to transfer a mirror surface and an ageing process are separated, a mold cooling means having a plurality of heat pipes 4 for cooling the mold 1 and a mold heating means having a plurality of heaters 3 for heating the mold are provided. The heat pipes and the heaters are provided to the die plate of a press machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aging device, and more particularly, it can be applied to an aging device used in a method for producing a plastic molded part, and in particular, an aging die can be uniformly and quickly heated and cooled. The present invention relates to an aging device capable of controlling the cooling rate of the aging mold easily and manufacturing the aging mold easily and at low cost.

[0002]

2. Description of the Related Art Conventionally, a method of manufacturing a plastic molded article is such that a plastic base material is preliminarily processed into a substantially final shape by injection molding, and then the plastic base material is inserted into a mold having a plurality of cavities. A method is known in which the injection step and the aging step, in which the plastic base material is melted and heated to a temperature equal to or higher than the glass transition point, an internal pressure of the resin is generated, and then gradually cooled to transfer a mirror surface, are separated from the injection step and the aging step. .

In the molding method of this plastic molded product, how quickly heating and cooling can be performed in the aging step, and the mold can be controlled with a good controllability so as to obtain a uniform temperature. Is important. On the other hand, in the aging device for performing the aging step, the aging die is provided with a heating unit in which a plurality of heaters are embedded and a cooling unit in which a plurality of heat pipes are embedded, and is embedded in the heating unit. Heating is performed by a plurality of heaters, while cooling is performed by a plurality of heat pipes buried in the cooling unit. Particularly in cooling, a cooling rate is appropriately controlled by circulating a coolant such as water and oil in the exposed portion of the heat pipe from the mold and adjusting the flow rate of the coolant.
Further, a fin is attached to the exposed portion and the cooling rate is appropriately controlled by adjusting the amount of air blown to the fin.

[0004]

However, in the conventional aging device as described above, cooling is performed in the cooling section in which a plurality of heat pipes provided in the aging die are buried, and the flow rate of the refrigerant is reduced. Since it is too wide to increase the flow velocity and sufficient heat exchange cannot be performed,
In addition to being unable to perform quick cooling and fine control of the cooling rate, the temperature of the refrigerant changes near the inlet and outlet of the refrigerant, so use a heat pipe near the inlet and a heat pipe near the outlet. The heat exchange efficiency of the mold was changed, and the mold could not be cooled uniformly.

When installing the heat pipe in the mold,
Since the heat pipe is easily damaged, the heat pipe cannot be press-fitted into the mold, and a clearance is created between the mold and the heat pipe, and heat loss from the mold reduces cooling efficiency. was there. Also, in heating with a heater, if an attempt is made to increase the heating rate, over-shut is likely to occur, and the heating may be unnecessarily long and take time.

Further, since the heater and the heat pipe were installed in the aging die, the aging die provided with the heater and the heat pipe had to be produced every time the molding target was changed, and the die was produced. In addition to the time and effort involved, the manufacturing cost was sometimes too high. Therefore, the present invention can uniformly and quickly heat and cool the aging mold, and can easily control the cooling rate of the aging mold, and moreover, the aging mold can be produced easily and at low cost. The purpose is to provide an aging device that can do.

[0007]

The invention according to claim 1 is
After processing the plastic base material into a substantially final shape by injection molding in advance, insert the plastic base material into an aging mold that is attached to a press machine and that can perform mold clamping and mold opening, Next, the plastic base material is melted and heated to a temperature not lower than the glass transition point to generate an internal pressure of the resin, and then gradually cooled to transfer a mirror surface, thereby producing a plastic molded product in which an injection step and an aging step are separated. The aging device used in the method has a mold cooling means having a plurality of heat pipes for cooling the mold and a mold heating means having a plurality of heaters for heating the mold. However, the heat pipe and the heater are provided on the die plate of the pressing machine.

According to a second aspect of the present invention, in the first aspect of the invention, there is provided a die plate exchanging means for exchanging the die plate for the heat pipe and the die plate not provided with the heater. It is a thing. The invention according to claim 3 is the member according to any one of claims 1 and 2, wherein the clearance between the heater and the heat pipe and the mold or the die plate is higher than the heating temperature of the mold. It is characterized by being embedded in.

According to a fourth aspect of the present invention, in the above-mentioned first to third aspects of the present invention, a mold temperature detecting means for detecting the temperature of the mold and a predetermined PID control based on the detected temperature of the mold. And a die heating means for heating the die to a temperature. In the invention according to claim 5, in the invention according to any one of claims 1 to 3, the time until the mold reaches a target temperature is predicted in advance, and when the predicted time is reached, the heater is turned on and off. It is characterized by having a mold heating means for heating the mold to a predetermined temperature by doing so.

According to a sixth aspect of the present invention, in the first to fifth aspects of the invention, a coolant is caused to flow in the flow path of the cooling section of the heat pipe, and the flow rate of the coolant is adjusted to adjust the flow rate of the mold. A mold cooling rate control means for controlling a cooling rate is provided, and a partition plate for adjusting the flow rate of the refrigerant is provided in the flow path of the cooling section. The invention according to claim 7 is the same as the invention according to claim 6,
The partition plate is provided in a direction perpendicular to the arrangement direction of the heat pipe in the cooling unit.

The invention according to claim 8 is characterized in that a honeycomb structure is provided in the flow path of the cooling part according to claims 6 to 7. The invention according to claim 9 is the invention according to any one of claims 1 to 8, wherein the heat pipe is provided with fins, and the amount of air supplied from the blower to the fins is adjusted based on the mold temperature. It is characterized in that a mold cooling speed control means for controlling the cooling speed of the mold is provided.

According to a tenth aspect of the present invention, in the above-mentioned ninth aspect, the mold cooling rate control means adjusts the cooling rate of the mold by adjusting the temperature of the cold air supplied to the fins. It is characterized by controlling. The invention according to claim 11 is the invention according to any one of claims 1 to 10, characterized in that the cavity has a nest structure, and only the nest is made of a member having a high thermal conductivity.

[0013]

According to the first aspect of the invention, since the heat pipe for cooling the aging die and the heater for heating the aging die are provided on the die plate of the press machine, the aging die is heated. The aging mold can be heated and cooled without providing a pipe and a heater. For this reason, it is not necessary to install a heat pipe and a heater in a mold that is newly replaced every time the mold is replaced, so that the time and cost for manufacturing the mold can be reduced.

According to the second aspect of the present invention, since the die plate has a die plate exchanging means for exchanging the die plate with an ordinary die plate having no heat pipe and heater, the press provided with the heat pipe and the heater is provided. The die plate of the machine can be replaced as appropriate with a die plate provided with nothing. For this reason, when a heat pipe and a heater are required for the aging mold depending on the object to be molded, the aging mold itself equipped with the heat pipe and the heater can be used, so that versatility can be provided.

According to the third aspect of the present invention, the clearance between the heater and the heat pipe and the mold or the die plate (a member having a melting point higher than the heating temperature of the mold is preferable in terms of heat resistance). Since it is configured to be embedded with a member such as a metal, the clearance between the heater and the heat pipe and the die or die plate can be embedded with a metal having a melting point higher than the die heating temperature. Therefore, since the clearance can be eliminated, the heat loss due to the clearance can be suppressed, the heat exchange efficiency at the time of heating and cooling can be increased accordingly, and the heating and cooling speeds can be increased, and the response The property can be improved.

According to a fourth aspect of the present invention, a mold temperature detecting means for detecting the temperature of the mold and a mold heating for heating the mold to a predetermined temperature by PID control based on the detected temperature of the mold. Since the die temperature is detected, the die temperature can be detected, and the die can be heated to a predetermined temperature by PID control based on the detected temperature of the die. Therefore, the mold can be heated accurately and quickly without causing overshoot or the like.

According to a fifth aspect of the present invention, the time required for the mold to reach a target temperature is predicted in advance, and when the predicted time is reached, the heater is turned on and off to control the mold to a predetermined temperature. Since the mold heating means for heating the mold is provided, the time required for the mold to reach the target temperature is predicted in advance, and when the predicted time is reached, the heater is ON-OFF controlled. The mold temperature can be heated to a predetermined temperature. Therefore, the aging die can be heated accurately and quickly without causing overshoot or the like.

According to a sixth aspect of the present invention, a mold cooling rate control means for controlling the cooling rate of the mold by causing a refrigerant to flow in the flow path of the cooling section of the heat pipe and adjusting the flow rate of the refrigerant. Since the partition plate for adjusting the flow rate of the refrigerant is provided in the flow path of the cooling unit, the flow path region is adjusted by the partition plate provided in the flow path of the cooling unit. As a result, the flow rate of the coolant can be adjusted to appropriately control the cooling rate of the mold. Therefore, for example, a partition plate can be provided in the flow path in parallel to the arrangement direction of the heat pipe to narrow the flow path as appropriate, and thus the flow velocity of the refrigerant flowing in the flow path can be increased. Accordingly, the heat exchange efficiency can be increased to accelerate the cooling rate of the mold, and the responsiveness can be improved.

According to the seventh aspect of the invention, since the partition plate is provided in a direction perpendicular to the arrangement direction of the heat pipe, the refrigerant can flow in the direction perpendicular to the heat pipe. Therefore, the plurality of heat pipes can be cooled more uniformly, so that the mold can be prevented from being unevenly cooled. In particular, it is possible to avoid uneven cooling of the mold caused by the temperature difference between the vicinity of the refrigerant outlet and the vicinity of the inlet.

According to the eighth aspect of the present invention, since the honeycomb structure is provided in the cooling section channel, the cross-sectional area in contact with the refrigerant can be increased. Therefore, it can be cooled quickly. In the invention according to claim 9, a mold cooling rate control for controlling the cooling rate of the mold by providing fins on the heat pipe and adjusting the amount of air supplied from the blower to the fins based on the mold temperature. Since it is configured by providing a means, for example, by electrically controlling the fan motor drive voltage of the blower with a voltage varying means based on the mold temperature detected by a temperature sensor installed in the mold The cooling temperature of the mold can be controlled by adjusting the air flow rate of the mold based on the mold temperature. Therefore, the cooling rate of the mold can be easily controlled.

According to the tenth aspect of the present invention, the die cooling rate control means is configured to control the cooling rate of the die by adjusting the temperature of the cold air supplied to the fins. The cooling rate of the mold can be controlled by adjusting the temperature of the cold air supplied to the mold. Therefore, the cooling air can be cooled by supplying it to the fins and adjusting the temperature thereof, so that the cooling can be performed more quickly than in the case of the invention described in claim 9.

According to the eleventh aspect of the present invention, since the cavity has a nest structure and only the nest is composed of a member having a high thermal conductivity, only the insert piece can be replaced when the object of the molded product is changed. For this reason, it is possible to prevent unnecessary labor and cost, and it is not necessary to configure the mold as a whole with costly members such as copper alloy with high thermal conductivity. The cost of the mold can be reduced by using a member having a high rate.

[0023]

EXAMPLE In the present invention, a plastic base material is preliminarily processed into a substantially final shape by injection molding, and then the plastic is applied to a mold having a plurality of cavities which is attached to a press machine so as to perform mold clamping and mold opening. Inserting the base material, then melting and heating the plastic base material to a temperature above the glass transition point to generate an internal pressure of the resin, and then gradually cooling to transfer the mirror surface to separate the injection step and the aging step. In an aging device used in a method for producing a plastic molded article, a mold cooling means having a plurality of heat pipes for cooling the mold, and a mold having a plurality of heaters for heating the mold. A die heating means is provided, and the heat pipe and the heater are provided on the die plate of the press machine so that the die can be replaced every time the die is replaced. That mold eliminates the need to install a heat pipe and heater, so that to reduce the labor and cost of the mold produced. Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a schematic perspective view showing the structure of an aging device according to an embodiment of the present invention. FIG. 1 (a) is a schematic perspective view showing a die plate and an aging die,
FIG. 1B is a schematic perspective view showing an aging die.
In FIG. 1, 1 is an aging die, and 2 is a die plate of a press machine provided with a heater 3 and a heat pipe 4. In this embodiment, as shown in FIG.
Since the heater 3 and the heat pipe 4 of the aging device are provided on the die plate 2 of the pressing machine, the die 1 can be heated and cooled without providing the heater 3 and the heat pipe 4 on the die 1. Therefore, as shown in FIG.
As shown in FIG. 5, it is not necessary to install the heat pipe 4 and the heater 3 in the mold 1 that is newly replaced every time the mold 1 is replaced. Therefore, it is possible to avoid the complexity of the mold structure and the time and effort for manufacturing the mold. It is possible to avoid unnecessary costs.

Next, the die plate 2 of the press equipped with the heater 3 and the heat pipe 4 may be replaced with a normal die plate provided with nothing. In this case, the die plate 2 provided with the heater 3 and the heat pipe 4 can be appropriately replaced with a normal die plate provided with nothing. Therefore, when the heat pipe 4 and the heater 3 are required for the mold 1 depending on the molded product, the mold 1 itself with the heat pipe 4 and the heater 3 installed can be used, so that versatility can be provided. .

Next, as the heating means of the aging device, the temperature of the mold 1 is detected by a temperature sensor installed in the mold 1, and the target temperature is reached by PID control based on the detected temperature of the mold 1. The mold 1 may be heated until that time. In this case, since the mold 1 can be heated to a predetermined temperature based on the detected temperature of the mold 1, it is possible to quickly and accurately perform heating without causing an overshoot or the like.

Next, the time required for the mold 1 to reach the target temperature is predicted in advance in consideration of the amount of overshoot, and when the predicted time is reached, the heater is set to be turned off. May be used, in this case O during heating
Fast heating can be performed without N-OFF. Next, it is unavoidable that a clearance is formed between the heater 3 and the heat pipe 4 and the mold 1, and the heat loss therefrom is large. Therefore, by embedding the clearance with metal, it may be possible to prevent the heat loss associated with the clearance, thereby increasing the heat exchange efficiency at the time of heating and cooling and speeding up the heating and cooling speed. As well as
Responsiveness can also be improved. In consideration of heat resistance, it is desirable to use a low melting point metal having a melting point equal to or higher than the heating temperature of the aging die 1.

Next, as a cooling method of the aging device, as shown in FIG. 2, a cooling part 21 for covering the heat pipe 4 is provided on the exposed part of the heat pipe 4 from the mold 1, and the flow path of this cooling part 21 is provided. A method may be adopted in which a cooling medium is circulated to cool the exposed portion of the heat pipe 4 quickly to cool the die 1, or as shown in FIG. 3, the heat pipe 4 is exposed from the die 1. A method may be adopted in which the fins 7 are attached to the parts, and the blower 8 supplies air to the fins 7 to quickly cool the exposed parts of the heat pipe 4 to cool the mold 1. The method of circulating the refrigerant and the method of supplying the wind may be performed on the heat pipe 4 provided on the die plate 2.

Next, in the method of circulating the exposed portion refrigerant of the heat pipe 4 of FIG. 2, in the flow path of the cooling unit 21, as shown in FIG. The partition plate 10 may be provided in parallel to the partition plate 10, and the partition plate 10 may be configured to appropriately narrow the flow path.
Since the flow velocity of the refrigerant flowing in the flow path can be increased,
The heat exchange efficiency can be increased and the cooling rate can be increased with good controllability. Further, as shown in FIG. 5, a partition plate 10 may be provided in a direction perpendicular to the arrangement direction of the heat pipe 4, and in this case, the refrigerant can flow in the direction perpendicular to the heat pipe 4. Therefore, it is possible to more uniformly cool the plurality of heat pipes 4 and prevent the mold 1 from being unevenly cooled. In particular, it is possible to avoid uneven cooling of the mold caused by the temperature difference between the vicinity of the refrigerant outlet and the vicinity of the inlet.

Next, in the method of attaching the fins 7 to the heat pipe 4 of FIG. 3 and supplying the air from the blower 8 to the fins 7, the amount of air supplied from the blower 8 to the fins 7 is
The fan motor drive voltage of the blower 8 may be controlled by electric control which is appropriately changed by the voltage changing means based on the temperature detection data from the temperature sensor installed in the mold 1. In this case, Since the amount of air from the blower 8 can be adjusted based on the temperature of the mold 1 by the above electrical control, accurate cooling control can be performed with good controllability. Alternatively, the cooling fan may be configured to control the cooling rate by adjusting the temperature of the wind from the blower 8 to be cool air. In this case, the cooling rate can be increased. The cooling rate may be controlled by combining the temperature and the air volume of the cold air, and more efficient control can be performed as compared with the case of adjusting only the air volume.

Next, as shown in FIG. 6, the honeycomb structure 12 may be provided in the flow path of the cooling part 21 through which the refrigerant flows, and in this case, the cross-sectional area in contact with the refrigerant can be increased. Therefore, the cooling rate can be increased. This method can also be applied to the method of supplying air from the blower 8 of FIG. 3 to the fins 7. Next, as shown in FIG.
A plurality of cavities may have a nesting structure, and only this nest may be configured by a member having a high thermal conductivity. In this case, when the target of the molded product 13 is changed, it is useless to replace only the insert piece 14. It is possible to prevent trouble and cost. Further, in order to quickly and uniformly heat and cool the mold 1, the mold member is made of a member having a high thermal conductivity such as a copper alloy, and the nest has a heater 3 as shown by A in FIG. Alternatively, by contacting the plate on which the heat pipe 4 is installed, it is not necessary to configure the mold 1 as a whole with a member having a high thermal conductivity, so that only the insert piece 13 is configured with a member having a high thermal conductivity. By doing so, heating and cooling can be performed quickly and uniformly, and it is possible to reduce the cost of the mold 1 because it is not necessary to configure the entire mold 1 with a costly member such as a copper alloy. it can.

[0032]

According to the present invention, the aging die can be uniformly and quickly heated and cooled, and
The cooling rate of the aging die can be easily controlled, and the aging die can be manufactured easily and at low cost.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing the configuration of an aging device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a cooling method of an aging device.

FIG. 3 is a diagram showing a cooling method of an aging device.

FIG. 4 is a diagram showing a cooling method of an aging device.

FIG. 5 is a diagram showing a cooling method of an aging device.

FIG. 6 is a diagram showing a cooling method of an aging device.

FIG. 7 is a diagram showing a case where a cavity has a nested structure.

[Explanation of symbols]

 1 Mold 2 Die Plate 3 Heater 4 Heat Pipe 7 Fins 8 Blower 10 Partition Plate 12 Honeycomb Structure 13 Molded Product 14 Inserting Piece 21 Cooling Section

Claims (11)

[Claims] 1. An aging die comprising a plurality of cavities, which is preliminarily processed into a final shape by injection molding and is then attached to a press machine so as to perform mold clamping and mold opening. Insert the material,
Next, the plastic base material is melted and heated to a temperature equal to or higher than the glass transition point to generate an internal resin pressure, and then,
In an aging device used in a method for producing a plastic molded product in which an injection step of gradually cooling and transferring a mirror surface and an aging step are separated, a die cooling having a plurality of heat pipes for cooling the die An aging apparatus comprising: a heating means and a die heating means having a plurality of heaters for heating the die, wherein the heat pipe and the heater are provided on a die plate of the pressing machine. 2. The aging apparatus according to claim 1, further comprising a die plate exchanging means for exchanging the die plate for the heat pipe and the die plate not provided with the heater. 3. The clearance between the heater and the heat pipe and the mold or the die plate is filled with a member having a melting point higher than a heating temperature of the mold. The aging device according to 2. 4. A mold temperature detecting means for detecting the temperature of the mold, and a mold heating means for heating the mold to a predetermined temperature by PID control based on the detected temperature of the mold. The aging device according to claim 1, which is characterized in that 5. A heater is turned on when a time required for the mold to reach a target temperature is predicted in advance and the predicted time is reached.
The aging apparatus according to claim 1, further comprising a mold heating unit that heats the mold to a predetermined temperature by controlling the -OFF. 6. A mold cooling rate control means for controlling a cooling rate of the mold by causing a refrigerant to flow in a flow path of a cooling part of the heat pipe and adjusting a flow rate of the refrigerant, the cooling The aging device according to any one of claims 1 to 5, wherein a partition plate for adjusting the flow rate of the refrigerant is provided in the flow path of the section. 7. The aging device according to claim 6, wherein the partition plate is provided in a direction perpendicular to an arrangement direction of the heat pipe in the cooling section. 8. The aging apparatus according to claim 6, wherein a honeycomb structure is provided in the flow path of the cooling section. 9. A mold cooling speed control means for controlling the cooling speed of the mold by providing fins on the heat pipe and adjusting the amount of air supplied from the blower to the fins based on the mold temperature. It is provided, It is characterized by the above-mentioned.
The aging device according to any one of claims 1 to 5. 10. The aging apparatus according to claim 9, wherein the mold cooling rate control unit controls the cooling rate of the mold by adjusting the temperature of the cold air supplied to the fins. 11. The aging device according to claim 1, wherein the cavity has a nest structure, and only the nest is configured by a member having high thermal conductivity.