JP5991678B2 - Mold cooling system and mold cooling method - Google Patents

Description

  The present invention relates to a mold cooling system and a mold cooling method for cooling a heated mold.

2. Description of the Related Art Conventionally, a mold cooling system (mold cooling apparatus) that supplies a cooling medium such as cooling water to a medium flow path provided in a mold in order to cool a heated mold is known. In such a mold cooling system, there is a problem that the cooling medium supplied to the medium flow path of the mold heated to a high temperature is vaporized in the medium flow path and the vapor is discharged.
For example, in Patent Document 1 below, a liquid supply conduit and a drain pipe for supplying a liquid at room temperature to a liquid circulation path configured by connecting a liquid passage of a mold and a liquid passage of a temperature controller, And connecting the liquid supply conduit and the drainage pipe by the throttle passage, thereby supplying the liquid at normal temperature through the throttle passage to the drainage pipe and suppressing the generation of vapor. A temperature control device is disclosed.

JP 2002-52538 A

  By the way, recently, a system for cooling a mold heated to a high temperature such as 150 ° C. to 300 ° C. has been desired along with an increase in size of a molded product and diversification of molding materials. In such a cooling system, when a cooling medium is sent to the medium flow path of the mold, the cooling medium is instantly vaporized in the medium flow path of the mold and the pressure rises, and the heat capacity of the mold is relatively low. In addition, the cooling medium is difficult to be sent from the cooling medium supply side to the mold medium flow path, the cooling time is prolonged, and a pump with a high discharge pressure is required. It was thought to do. For example, as in Patent Document 1 above, it is conceivable to supply liquid to the path on the discharge side of the mold to condense, but it is difficult to supply liquid due to an increase in pressure as in the case of the medium feeding side. It is conceivable that a pump with a high discharge pressure is required.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a mold cooling system and a mold cooling method capable of improving cooling efficiency while being able to suppress discharge of a vaporized cooling medium. Yes.

In order to achieve the above object, a mold cooling system according to the present invention is a mold heated by a mold heater that is energized and controlled so that the mold temperature reaches a preset heating target temperature of 150 ° C. or higher. A system for cooling a mold by supplying a cooling medium from a cooling medium supply source to a medium flow path provided in the mold, the discharge side path being connected to an outlet side of the medium flow path of the mold Is connected to a heat exchanger for condensing the vaporized cooling medium discharged from the medium flow path, while being connected to the inlet side of the medium flow path of the mold, the supply side path from the cooling medium supply source , the steam or air from a steam source or air source which is configured such that connecting the route for supplying the heating step of heating so that the heating target temperature of the mold by the mold heater is performed In the cooling process after, and controls the supply of the steam or the air supply and the cooling medium, after performing the pre-cooling step of supplying the steam or the air in the medium passage of said mold, said mold It has a control part which performs this cooling process which supplies the above-mentioned cooling medium to a medium flow passage.

In the present invention, a cooling path provided so as to branch from the supply side path is connected to a low temperature side flow path of the heat exchanger and connected to a return side of the cooling medium supply source, and It is good also as a structure which connected the said discharge side path | route downstream of a heat exchanger to the return medium side of the said cooling medium supply source .
In the present invention, the control unit controls the supply of the steam or the air supply and the cooling medium, after to supply the cooling medium to the medium flow path of the mold, the mold The steam or the air may be supplied to the medium flow path.
Moreover, in this invention, you may provide the backflow prevention part which prevents a backflow in the discharge side path | route downstream of the said heat exchanger.

In order to achieve the above object, the mold cooling method according to the present invention is heated by a mold heater that is energized and controlled so that the mold temperature becomes a preset heating target temperature of 150 ° C. or higher. A method of cooling a mold by supplying a cooling medium to a medium flow path provided in the mold, and heating the mold so that the heating target temperature is reached by the mold heater In the cooling process after the process is executed, the pre-cooling process for supplying steam or air to the medium flow path of the mold is performed, and then the main cooling process for supplying the cooling medium to the medium flow path of the mold is performed. And a discharge side path connected to the outlet side of the medium flow path of the mold is communicated with a heat exchanger, and the vaporized cooling medium discharged from the medium flow path is condensed in the heat exchanger. Features .

In the present invention, a cooling path provided to branch from a supply side path for supplying the cooling medium to the medium flow path of the mold is communicated with a low temperature side flow path of the heat exchanger, and the cooling path The cooling medium that has passed through is returned to the return side of the cooling medium supply source that supplies the cooling medium, and the cooling medium that has passed through the discharge side path downstream of the heat exchanger is returned to the cooling medium supply source. The medium may be returned to the return side .
Moreover, in this invention, after performing the 1st cooling process as the said main cooling process, you may make it perform the 2nd cooling process which supplies steam or air to the medium flow path of the said metal mold | die.

  Since the mold cooling system and the mold cooling method according to the present invention are configured as described above, the cooling efficiency can be improved while the discharge of the vaporized cooling medium can be suppressed.

1 is a schematic system configuration diagram schematically showing an example of a mold cooling system according to an embodiment of the present invention. It is a schematic time chart which shows typically an example of basic operation performed in the metallic mold cooling system. It is a schematic system block diagram which shows typically an example of the metal mold | die cooling system which concerns on other embodiment of this invention. It is a schematic time chart which shows typically an example of basic operation performed in the metallic mold cooling system. It is a schematic system block diagram which shows typically an example of the metal mold | die cooling system which concerns on further another embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
In FIG. 1, FIG. 3, and FIG. 5, a pipe (pipe) or the like that is a path through which a medium or the like passes is schematically shown by a solid line.
2 and 4 schematically show the ON / OFF operation and the opening / closing operation of each device.

1 and 2 are explanatory views for explaining a mold cooling system according to the first embodiment and a mold cooling method executed using the mold cooling system.
The mold cooling system 1 according to this embodiment is configured to cool a heated mold 2 by supplying a cooling medium from a cooling medium supply source 10 to a medium flow path 4 provided in the mold 2. Has been. As shown in FIG. 1, the mold cooling system 1 uses a discharge side path 15 connected to the outlet 5 side of the medium flow path 4 of the mold 2, and a vaporized cooling medium discharged from the medium flow path 4. It is set as the structure connected to the heat exchanger 20 to condense.
In the present embodiment, the mold cooling system 1 is a mold heating / cooling system 1 that performs heating in addition to cooling of the mold 2.

The mold 2 has, for example, a configuration having a fixed mold and a movable mold, and the fixed mold and the movable mold are respectively provided with medium flow passages 4 and 4 for circulating a cooling medium. A supply-side path (medium feeding path) 13 is connected to the inlets (medium feeding ports) 3 and 3 of these medium flow paths 4 and 4, and an outlet (medium returning port) 5 of the medium flow paths 4 and 4. , 5 side is connected to a discharge side path (return medium path) 15.
The supply side path 13 and the inlets 3 and 3 of the medium flow paths 4 and 4 are a manifold part that branches the single supply side path 13 into a plurality of parts, hoses and tubes connected to a plurality of connection ports of the manifold part, etc. It is good also as a structure connected through the piping material which has this flexibility.
Further, the discharge side passage 15 and the outlets 5 and 5 of the medium flow passages 4 and 4 are connected to a manifold portion for branching the single discharge side passage 15 into a plurality of ports and a plurality of connection ports of the manifold portion. It is good also as a structure connected through flexible piping materials, such as a hose and a tube.

The mold 2 is provided with a temperature sensor 6 as a detecting means for detecting the temperature of the mold 2. The temperature sensor 6 may detect the temperature of a medium (cooling medium) on the outlet 5 side such as a portion in the vicinity of the outlet 5 of the medium flow passage 4 or a portion in the vicinity of the downstream side of the outlet 5.
The mold 2 is provided with a mold heater 7 as a heating means for heating the mold 2. In the illustrated example, an example is shown in which the mold heaters 7 and 7 are embedded in the fixed mold and the movable mold of the mold 2, respectively.
The heating target temperature (heating set temperature, see FIG. 2) of the mold 2 heated by the mold heater 7 as the heating means depends on the size and shape of the molded product, the type of the molding material, etc. You may make it set suitably from a viewpoint etc. which improve the filling property of a material, and the transferability (transfer rate) of the cavity surface to a molded article. For example, when the molded product is relatively large, the heating target temperature may be about 150 ° C. to 300 ° C., which is a relatively high temperature, or about 200 ° C. to 300 ° C.

  Further, the cooling target temperature (cooling set temperature, see FIG. 2) of the mold 2 cooled by the cooling medium from the cooling medium supply source 10 which will be described later can also be used in the molding cycle because the molten material can be solidified. You may make it set suitably from a viewpoint of aiming at shortening. The cooling target temperature may be lower than the heating target temperature, but if it is too low, the time until the cooling target temperature is reached is prolonged due to the large heat capacity of the mold 2. In addition, the time until the heating target temperature is reached in the next heating step tends to be prolonged. From such a viewpoint and the like, the cooling target temperature may be, for example, about 100 ° C. to 200 ° C., or about 150 ° C. to 200 ° C. Moreover, when the heating target temperature is set to a relatively high temperature as described above, a temperature lower by about 40 ° C. to 120 ° C. than the heating target temperature may be set as the cooling target temperature.

As a molding machine for the mold 2, a synthetic resin as a material melted by a cylinder or the like is injected into a cavity or the like formed by the fixed mold and the movable mold of the mold 2 from a nozzle or the like. In addition, an injection molding machine or the like that sequentially molds the molded product may be used, or another molding machine such as a compression molding machine may be used. Moreover, as a molding material, it is good also as a fiber reinforced synthetic resin material etc. which made the synthetic resin material contain reinforcing fibers, such as carbon fiber and glass fiber.
The means for heating the mold 2 is not limited to the mold heater 7 described above, and a heating medium supply source for supplying a heating medium to a medium flow path provided in the mold 2 may be used as the heating means. In this case, the heating medium may be sent to the same medium flow path as the cooling medium, or the heating medium may be sent to the medium flow path dedicated to the heating medium. In addition, various heating means can be employed. Furthermore, the mold 2 may be heated by the self-heating of the molten material injected into the cavity of the mold 2.

The cooling medium supply source 10 can employ an appropriate supply source according to the type of the cooling medium, the required temperature of the cooling medium itself, the cooling target temperature, and the like. For example, the cooling medium supply source 10 stores the cooling medium. And a cooling medium supply pump 11 (see FIG. 2) that supplies (sends) the cooling medium stored in the storage part toward the mold 2 side. Also good. In this case, temperature control may be performed by a cooler such as an appropriate chiller so that the cooling medium stored in the storage unit is maintained at a predetermined temperature set in advance.
The cooling medium supplied by the cooling medium supply source 10 is liquid on the supply side and is water (pure water) in the present embodiment, but may be ethanol, other alcohols, or other cooling medium. . Moreover, you may make it employ | adopt the cooling medium whose boiling point in a normal pressure is 100 degrees C or less.

The temperature of the cooling medium supplied from the cooling medium supply source 10 may be about room temperature, or may be about 5 ° C. to 90 ° C. or about 10 ° C. to 50 ° C., for example.
Further, the cooling medium supply source 10 is not limited to the above, and may be provided with a storage unit that is not temperature-controlled, or a cooling tower or the like installed in a factory or the like may be used as the cooling medium supply source. Water supply (industrial water supply, water supply) may be used as a cooling medium supply source.

In this embodiment, the mold heating / cooling system 1 is connected to the steam source 8 on the supply side paths 12 and 13 from the cooling medium supply source 10 connected to the inlet 3 side of the medium flow path 4 of the mold 2. In addition, paths 18 and 19 for supplying steam and air from the air source 9 to each other are connected.
The steam source 8 may be a boiler that heats and evaporates a liquid (preferably the same type of liquid as the cooling medium supplied from the cooling medium supply source 10 to the medium flow path 4 of the mold 2) with a heat source. Good.
The steam supply path 18 for supplying steam from the steam source 8 is provided with a steam valve 18a including an electromagnetic valve for supplying or blocking the steam from the steam source 8. One end of the steam supply path 18 is connected to the steam source 8, and the other end is connected to the supply side path 13 via an appropriate joint or the like. The temperature of the steam supplied from the steam source 8 may be set as appropriate according to the above-described cooling target temperature. For example, the temperature may be approximately the same as the above-described cooling target temperature. Alternatively, the temperature may be lower than the cooling target temperature.

The air source 9 is configured to blow air or the like with a blower, for example, a gas compressed by a compressor such as a compressor (high pressure gas) through an after cooler, a drain separator, a dryer, or the like. It is good also as compressed air sources, such as a gas tank to store.
An air supply path 19 for supplying air from the air source 9 is provided with an air valve 19a including an electromagnetic valve for supplying or blocking air from the air source 9. One end of the air supply path 19 is connected to the air source 9, and the other end is connected to the supply side path 13 via an appropriate joint or the like.

Supply-side paths 12 and 13 that connect the cooling medium supply source 10 and the inlet 3 of the medium flow path 4 of the mold 2 are upstream of the connection portion between the steam supply path 18 and the air supply path 19 (cooling). A supply side path 12 on the medium supply source 10 side and a supply side path 13 on the downstream side (on the mold 2 side) of the connection portion are provided.
The supply side path 12 upstream of the supply side paths 12 and 13 is provided with a cooling medium valve 12a including an electromagnetic valve for supplying or blocking the cooling medium from the cooling medium supply source 10. Further, the above-described cooling medium supply pump 11 is disposed in the upstream supply side path 12. In addition, a detection means such as a temperature sensor for detecting the temperature of the cooling medium fed toward the medium flow path 4 of the mold 2 is provided in the upstream supply side path 12 and the storage section, and this detection is performed. The temperature may be adjusted by the above-described cooler or the like so that the temperature of the cooling medium becomes a predetermined temperature set in advance based on the detected value of the means.

The heat exchanger 20 uses a cooling medium fed through the discharge side path 15 connected to the outlet 5 of the medium flow path 4 of the mold 2 as a high-temperature fluid, and a low-temperature fluid that cools and condenses the high-temperature fluid is sent to the heat exchanger 20. The cooling path 14 to be transmitted is communicated. The discharge side path 15 and the cooling path 14 may be connected to the high temperature side flow path and the low temperature side flow path of the heat exchanger 20, respectively.
In this heat exchanger 20, the cooling medium vaporized through the medium flow path 4 of the mold 2 heated to a high temperature is absorbed by the low-temperature fluid sent through the cooling path 14, cooled, condensed, and liquefied. .
In the present embodiment, the cooling path 14 is configured to send the cooling medium supplied from the cooling medium supply source 10 to the low-temperature channel of the heat exchanger 20. That is, the cooling medium supply source 10 that supplies the cooling medium to the medium flow passage 4 of the mold 2 is also used as a supply source that supplies the cooling medium to the low-temperature side flow path of the heat exchanger 20. With such a configuration, a simple configuration can be achieved as compared with a configuration in which a cooling medium supply source is separately provided for the heat exchanger 20.

The cooling path 14 is connected to the upstream side of the upstream side of the supply side path 12 where the cooling medium valve 12a is provided via an appropriate joint or the like. In other words, the upstream-side supply-side path 12 includes a supply-side path 12 toward the mold 2 and a cooling path 14 toward the heat exchanger 20 on the upstream side of the portion where the cooling medium valve 12a is provided. It is branched to.
The cooling path 14 is provided with a heat exchanger cooling valve 14a including an electromagnetic valve or the like for supplying or blocking the cooling medium from the cooling medium supply source 10.
The cooling path 14 is connected to the medium return side of the cooling medium supply source 10.

In the present embodiment, the discharge side path 15 (the discharge side path 15 downstream of the heat exchanger 20) connected to the outlet 5 of the medium flow path 4 of the mold 2 and passing through the heat exchanger 20 is connected to the cooling medium. The supply source 10 is connected to the medium return side. That is, the cooling medium supplied to the medium flow path 4 of the mold 2 is configured to circulate in a closed loop with the cooling medium supply source 10. With such a configuration, impurities and the like are hardly mixed, and the quality control of the cooling medium can be easily performed.
In the illustrated example, an example in which the discharge side path 15 on the downstream side of the heat exchanger 20 is connected so as to join the cooling path 14 on the downstream side of the heat exchanger 20 is illustrated.

Moreover, in this embodiment, it is set as the structure which provided the backflow prevention part 16 which prevents a backflow in the discharge side path | route 15 of the downstream of the heat exchanger 20. FIG.
In the present embodiment, the backflow prevention unit 16 allows the flow of fluid from the heat exchanger 20 side to the cooling medium supply source 10 side, while allowing fluid to flow from the cooling medium supply source 10 side to the heat exchanger 20 side. A check valve (check valve, check valve) that prevents flow is used. By adopting such a backflow prevention valve as the backflow prevention unit 16, for example, opening / closing control or the like becomes unnecessary when discharging (returning medium) compared to a case where an on / off valve or the like is provided as the backflow prevention unit. The backflow can be prevented with simple control.

As the heat exchanger 20 described above, various heat exchange methods such as a double tube heat exchanger, a plate heat exchanger, a shell and tube heat exchanger, a cross fin heat exchanger, and the like are available. It is possible to adopt a heat exchanger. Moreover, although the heat exchanger 20 like a parallel flow type is illustrated in the example of the figure, you may make it employ | adopt heat exchangers, such as a counterflow type and a crossflow type.
Further, a steam trap or the like may be appropriately provided in the discharge side path 15 (the discharge side path 15 upstream of the backflow prevention unit 16) on the downstream side of the heat exchanger 20 as necessary.
In the example shown in the figure, the valves for opening and closing the upstream supply side path 12, the cooling path 14, the steam supply path 18 and the air supply path 19 are individually set as on-off valves (ON / OFF valves). However, all or any of these may be configured by a multi-port multi-position switching valve or the like.

Further, the mold heating / cooling system 1 includes a control panel 21 including the mold heater 7, the cooling medium supply pump 11, and a controller 22 that controls the valves 12 a, 14 a, 18 a, and 19 a.
The control panel 21 includes a control unit 22 composed of a CPU and the like, a display unit connected to the control unit 22 via signal lines and the like for setting, inputting, and displaying various settings. The display operation unit 24 constituting the operation unit, and various programs such as a control program for executing the setting conditions and input values set and input by the operation of the display operation unit 24 and each operation described later are set in advance. The storage unit 23 stores various operating conditions, various data tables, and the like, and includes various memories.

The control unit 22 includes clocking means such as a clock timer, an arithmetic processing unit, and the like, and is connected to the mold heater 7, the cooling medium supply pump 11, and the valves 12a, 14a, 18a, and 19a via signal lines and the like. These are configured to control these. The control unit 22 is also connected to the temperature sensor 6 of the mold 2 described above via a signal line or the like.
In the present embodiment, the control unit 22 is configured to control the supply of steam and air and the supply of the cooling medium.
In the present embodiment, as shown in FIG. 2, the control unit 22 supplies steam to the medium flow path 4 of the mold 2 and then supplies the cooling medium to the medium flow path 4 of the mold 2. It is set as the structure controlled to.
In the present embodiment, as shown in FIG. 2, the control unit 22 supplies air to the medium flow path 4 of the mold 2 after supplying the cooling medium to the medium flow path 4 of the mold 2. It is set as the structure controlled to.

  As the mold cooling device constituting the mold heating / cooling system 1, as shown by the two-dot chain line in FIG. 1, the open / close valves disposed in the paths 12, 14, 18, 19 described above. 12a, 14a, 18a, 19a, the backflow prevention unit 16, the heat exchanger 20, and the control panel 21 may be grasped, and in addition to this, the steam source 8, the air source 9 and It may be understood that at least one of the cooling medium supply sources 10 is provided. Further, in addition to such a mold cooling apparatus, it may be understood as a mold heating / cooling apparatus further provided with a heating means 7 for heating the mold 2.

In the mold heating / cooling system 1 according to the present embodiment configured as described above, the mold 2 is heated when the mold heater 7 is activated. The mold heater 7 is controlled by the control unit 22 so that the temperature of the mold 2 becomes a preset heating target temperature based on the measured temperature signal (detected temperature) of the temperature sensor 6 of the mold 2. Control of energization such as control may be performed. The heating target temperature may be input and set via the display operation unit 24.
When the cooling medium supply pump 11 is activated and the cooling medium valve 12a is opened, the cooling medium from the cooling medium supply source 10 is supplied to the medium flow path 4 of the mold 2 (circulation supply in this embodiment). Is done.

Further, when the cooling medium supply pump 11 is activated and the heat exchanger cooling valve 14 a is opened, the cooling medium from the cooling medium supply source 10 is supplied to the low temperature side flow path of the heat exchanger 20. The heat exchanger cooling valve 14a generates a measurement temperature signal (detected temperature) of a temperature sensor that detects the temperature downstream of the heat exchanger 20 in the discharge-side path 15 communicated with the high-temperature side flow path of the heat exchanger 20. On the basis of this, the controller 22 may perform opening / closing control such as PID control so that the temperature of the cooling medium to be returned becomes a preset return target temperature. This return medium target temperature may be input and set via the display operation unit 24.
If the steam valve 18 a is opened, the steam from the steam source 18 is supplied to the medium flow path 4 of the mold 2.
If the air valve 19 a is opened, air from the air source 19 is supplied to the medium flow path 4 of the mold 2.

Next, an example of a mold heating / cooling method (mold cooling method) as an example of a basic operation executed in the mold heating / cooling system 1 according to the present embodiment configured as described above will be described with reference to FIG. I will explain.
In the graph of FIG. 2, the horizontal axis is the time axis and the vertical axis is the detected temperature of the temperature sensor 6, and the transition is schematically shown.

First, you may make it perform the preheating process which starts the metal mold | die heater 7 and preheats the metal mold | die 2 of about normal temperature until it becomes about cooling target temperature. If preheated in this way, it will be in a standby state.
In the molding machine for the mold 2, although not shown, the mold 2 is closed, and a molten material such as resin is injected into a cavity provided in the mold 2 and filled appropriately. When the pressure is maintained and the molten material is solidified, the mold is opened and the molded product is taken out. In such a series of molding processes, a mold heating process is performed so that the solidification of the molten material is delayed and filling is performed smoothly, and the mold according to the present embodiment is used to perform this mold heating process. A heating / cooling system 1 is used. In addition, after the molten material is filled into the cavity, a mold cooling process is performed to quickly solidify the molten material, and the mold heating / cooling according to the present embodiment is performed in order to execute the mold cooling process. System 1 is used. The mold heating process and the mold cooling process executed by using the mold heating / cooling system 1 are linked to the molding operation of the molding machine, for example, a mold closing signal, an injection signal, a pressure holding signal of the molding machine. It is also possible to execute (start and stop) based on a mold opening signal or the like.

If the molding machine side signal or other heating start signal is received in the pre-heated state as described above, a heating process for heating the mold 2 is executed, and the mold 2 is set to a preset heating target temperature. It is heated to become. This heating process may be terminated if a signal on the molding machine side or other heating end signal is received, or may be terminated after a predetermined time has elapsed after reaching the heating target temperature. .
When this heating process is completed and a predetermined time has passed, or when a signal on the molding machine side or other cooling start signal is received, a cooling process for cooling the mold 2 is executed, and the mold 2 is Cooling is performed to achieve the set cooling target temperature. The cooling target temperature may be input and set via the display operation unit 24.

In the present embodiment, as described above, the heat exchanger cooling valve 14a for supplying or shutting off the low temperature medium (cooling medium) is provided in the low temperature side flow path of the heat exchanger 20, so this is performed during the cooling process. Opening / closing control of the heat exchanger cooling valve 14a is performed. In addition, when it is set as the aspect which does not provide such a heat exchanger cooling valve 14a like 2nd Embodiment and 3rd Embodiment which are mentioned later, a low-temperature medium (cooling | cooling) is provided in the low temperature side flow path of the heat exchanger 20. The medium may be constantly supplied.
Further, in this operation example, prior to supplying the cooling medium to the medium flow path 4, a pre-cooling step of supplying steam to the medium flow path 4 is executed. That is, with the cooling medium valve 12 a closed, the steam valve 18 a is opened, and steam is supplied to the medium flow passage 4. If steam is supplied in this way, the heat is absorbed by the contact with the inner peripheral surface of the medium flow passage 4 and the like, precooling is performed, and the heat exchanger 20 is reached for condensation. As a result, the pressure in each of the supply side path 13, the medium flow path 4, and the discharge side path 15 drops. That is, it is also possible to provide the backflow prevention unit 16 by vaporizing the cooling medium attached to the inner peripheral surface of the steam and the medium flow passage 4 and condensing and liquefying sequentially in the heat exchanger 20. As a result, the pressure in each of the paths drops rapidly.

This pre-cooling step may be executed so that the supply side path 13, the medium flow path 4 and the discharge side path 15 are substantially filled with steam. Further, this pre-cooling step may be executed until a predetermined time elapses, or a path such as a pressure sensor provided in any one of the supply side path 13, the medium flow path 4 and the discharge side path 15. You may make it perform until the measurement pressure signal (detection pressure) of the detection means which detects the pressure in this falls below the predetermined pressure (threshold value) set beforehand. In other words, the steam supply may be switched to the coolant supply if the pressure is lower than the predetermined pressure. For example, the predetermined pressure may be a pressure at which the cooling medium to be supplied next can be supplied. For example, the predetermined pressure is appropriately set according to the capacity (discharge pressure) of the cooling medium supply pump 11 or the like. May be. The predetermined pressure may be input and set via the display operation unit 24.
In this pre-cooling step, a small amount of cooling medium may be mixed and supplied to the steam, or air may be supplied instead of supplying steam. A small amount of cooling medium or steam may be mixed and supplied.

After performing the pre-cooling process in this way, the main cooling process for supplying the cooling medium to the medium flow path 4 of the mold 2 is performed. That is, the cooling medium supply pump 11 is started, the steam valve 18a is closed, and the cooling medium valve 12a is opened. In the illustrated example, the cooling medium supply pump 11 is activated earlier than the cooling medium valve 12a is opened in consideration of the rise time and the like.
In this operation example, after the first cooling process including the main cooling process is performed, the second cooling process for supplying air to the medium flow path 4 of the mold 2 is performed. That is, the cooling medium valve 12 a is closed, the air valve 19 a is opened, and air is supplied to the medium flow passage 4. Note that the cooling medium supply pump 11 may be stopped when the cooling medium valve 12a is closed. Further, a bypass path for connecting the supply side path 12 and the discharge side path 15 (cooling path 14 in the figure) is provided, and the bypass valve provided in this bypass path is interlocked with the opening / closing of the cooling medium valve 12a. On the contrary, the cooling medium supply pump 11 may be operated at all times in principle by opening and closing.

The first cooling step and the second cooling step can generally discharge (purge) the cooling medium in the medium flow path 4 by executing the second cooling step, so that overcooling or the like does not occur. You may make it perform each until predetermined time passes so that it may not fall below cooling target temperature largely at the end of a process. Alternatively, the first cooling process may be switched to the second cooling process based on the temperature detected by the temperature sensor 6, and the second cooling process may be terminated, that is, the air valve 19a may be closed.
In the second cooling step, instead of or in addition to air, a small amount of cooling medium may be intermittently supplied as in the operation example of the second embodiment to be described later. You may make it supply. When supplying steam in this way, a small amount of cooling medium may be intermittently supplied in addition to steam. Further, when supplying steam or a small amount of cooling medium in this way, substantially the entire amount is vaporized in the medium flow passage 4 at the end of the second cooling step, and the amount of medium remaining in the medium flow passage 4 is substantially reduced. The supply control may be performed as appropriate so that there is no problem. For example, the amount of heat released from the inner wall surface of the medium flow passage 4 is calculated based on the volume of the medium flow passage 4, the mold temperature before and after filling with a molten material such as resin, and the amount of heat of vaporization and cooling of the medium. It may be determined experimentally or empirically in consideration of the target temperature or the like. In addition, since it is considered that vaporization occurs during the mold opening and taking-out process, a relatively small amount of residual medium may be present.

After performing this cooling process, in the metal mold | die 2, a mold opening and taking-out of a molded article are made | formed suitably, and a heating process and a cooling process are repeatedly performed.
Thus, by performing the heating process for heating the mold 2 and the cooling process for cooling, the transferability (transfer rate) of the cavity surface to the molded product can be improved, and the molding cycle can be improved. Can be shortened.

The mold cooling system (mold heating / cooling system) 1 according to the present embodiment and the mold cooling method (mold heating / cooling method) executed using the mold cooling system 1 are configured as described above. Although the discharge of the vaporized cooling medium can be suppressed, the cooling efficiency can be improved.
That is, the discharge side path 15 connected to the outlet 5 side of the medium flow path 4 of the mold 2 is communicated with the heat exchanger 20 that condenses the vaporized cooling medium discharged from the medium flow path 4. Therefore, the vaporized cooling medium can be condensed in the heat exchanger 20, and discharge of the vaporized cooling medium can be suppressed. Further, by condensing in the heat exchanger 20, it is possible to reduce the pressure that has increased due to vaporization of the cooling medium. Thereby, it becomes easy to send the cooling medium to the medium flow path 4, the cooling time can be shortened, and the cooling efficiency can be improved.

  Further, in the present embodiment, the discharge side path 15 on the downstream side of the heat exchanger 20 is configured to return the medium to the cooling medium supply source 10, that is, the cooling medium is circulated. Therefore, compared to a configuration in which a new cooling medium is supplied and discharged without circulating the cooling medium, the medium flow passage 4 of the mold 2 such as silica or scale contained in the cooling medium by vaporization of the cooling medium. And the like can be reduced. Thereby, the maintenance frequency etc. of the medium flow path 4 can be reduced.

Moreover, in this embodiment, it is set as the structure which provided the backflow prevention part 16 which prevents a backflow in the discharge side path | route 15 of the downstream of the heat exchanger 20. FIG. Therefore, when the cooling medium vaporized in the heat exchanger 20 is condensed, the pressure in the path can be reduced more effectively. Thereby, it becomes easier to send the cooling medium to the medium flow path 4, the cooling time can be further shortened, and the cooling efficiency can be greatly improved.
The backflow prevention unit 16 is not limited to the backflow prevention valve as shown in the figure, and may be an on-off valve that is controlled to open and close by the control unit 22. In this case, the pressure drop accompanying the condensation in the heat exchanger 20 is detected by a pressure sensor or the like, or the temperature drop is detected by a temperature sensor or the like. The medium may be discharged (returned).

  Further, as in the example described above, the supply of steam or air and the supply of the cooling medium are controlled, and after the steam or air is supplied to the medium flow path 4 of the mold 2, the medium flow path 4 of the mold 2 is supplied. It is good also as a structure provided with the control part 22 which supplies a cooling medium. That is, the cooling medium may be supplied to the medium flow path 4 of the mold 2 after the pre-cooling step of supplying steam or air to the medium flow path 4 of the mold 2. With such a configuration, the mold 2 can be pre-cooled with steam or air, and it becomes easier to send the cooling medium to the medium flow path 4 later. That is, the heat of the medium flow path 4 of the mold 2 can be absorbed by the medium vaporized by mixing the medium with steam or air. Further, the vaporized medium mixed with steam or air is condensed in the heat exchanger 20, so that the pressure can be lowered, and this also makes it easier to send the cooling medium to the medium flow path 4. Become.

  Further, as in the above-described example, the supply of the steam or air and the supply of the cooling medium are controlled, the cooling medium is supplied to the medium flow path 4 of the mold 2, and then the steam is supplied to the medium flow path 4 of the mold 2. Or it is good also as a structure provided with the control part 22 which supplies air. That is, after the first cooling process for supplying the cooling medium to the medium flow path 4 of the mold 2 is performed, the second cooling process for supplying steam or air to the medium flow path 4 of the mold 2 is performed. Also good. With this configuration, the mold 2 can be cooled by absorbing heat by contact with the medium flow path 4 while purging the cooling medium remaining in the medium flow path 4 of the mold 2. Thereby, the residual medium remaining in the medium flow path 4 of the mold 2 can be reduced, and efficient heating can be performed.

Next, an example of a mold cooling system according to another embodiment of the present invention and an example of a mold cooling method executed using the mold cooling system will be described.
3 and 4 are explanatory diagrams for explaining a mold cooling system and a mold cooling method executed using the mold cooling system according to the second embodiment.
Note that differences from the first embodiment will be mainly described, and the same components are denoted by the same reference numerals, and description thereof will be omitted or simplified. Also, the description of the same operation as the above operation example will be omitted or briefly described.

Also in this embodiment, the mold cooling system 1A is a mold heating / cooling system 1A that performs heating in addition to cooling of the mold 2.
In the present embodiment, the steam supply path 18 for supplying steam from the steam source 8 is not connected to the supply side path 13, and the cooling path 14 communicated with the low temperature side flow path of the heat exchanger 20. The main difference from the first embodiment is that the heat exchanger cooling valve 14a is not provided, the backflow prevention unit 16 is not provided in the discharge-side path 15 on the downstream side of the heat exchanger 20, and the like.

In the present embodiment, the cooling medium supply amount from the cooling medium supply source 10 can be increased or decreased. In the illustrated example, a small flow rate path 12b is provided in parallel on the upstream supply side path 12 connected to the medium feeding side of the cooling medium supply source 10, and the cooling medium is supplied to or cut off from the small flow path 12b. The cooling medium small amount valve 12c is provided. That is, if the upstream supply side path 12 is a main path, the cooling medium valve 12a provided in the supply side path 12 is closed, and the cooling medium small amount valve 12c of the small flow path 12b is opened. In addition, a cooling medium with a small flow rate is supplied. This cooling medium small quantity valve 12c is connected to the control unit 22 through a signal line or the like, like other valves, and is controlled to be opened and closed by the control unit 22.
In addition, it is good also as an aspect etc. which replaced with such an aspect and provided the flow volume adjustment valve etc. which can control opening degree as the cooling medium valve 12a.

Next, an example of a mold heating / cooling method (mold cooling method) as an example of a basic operation executed in the mold heating / cooling system 1A according to the present embodiment having the above-described configuration will be described with reference to FIG. I will explain.
In the graph of FIG. 4 as well, the horizontal axis is the time axis and the vertical axis is the detected temperature of the temperature sensor 6, and the transition is schematically shown.

First, similarly to the above, a preheating process may be performed and a heating process may be performed.
Next, a cooling process for cooling the mold 2 may be performed.
In this operation example, the cooling medium is supplied to the medium flow path 4 of the mold 2 without executing the pre-cooling step of supplying steam or air to the medium flow path 4 of the mold 2. That means
The cooling medium supply pump 11 is activated, and the cooling medium valve 12 a is opened so that the cooling medium from the cooling medium supply source 10 is supplied to the medium flow path 4 of the mold 2. In the example shown in the figure, the cooling medium supply pump 11 is started earlier than the opening of the cooling medium valve 12a in consideration of the rise time and the like, as described above.

  In this operation example, after the first cooling process including the main cooling process is performed, the second cooling process for intermittently supplying the cooling medium and the air with a small flow rate to the medium flow path 4 of the mold 2 is performed. Like to do. In this operation example, the cooling medium valve 12a is closed, the cooling medium small amount valve 12c is opened intermittently, and a small flow rate of cooling medium is intermittently supplied to the medium flow passage 4 of the mold 2, and then the air valve 19a is intermittently opened, and air is intermittently supplied to the medium flow path 4 of the mold 2. Note that the cooling medium supply pump 11 may be stopped when the cooling medium small amount valve 12c is closed. In place of the above-described embodiment, in the second cooling step, the air valve 19a is intermittently opened to supply air intermittently to the medium flow path 4 of the mold 2, and then the cooling medium small amount valve It is good also as a structure which opens 12c intermittently and supplies the cooling medium of a small flow volume to the medium flow path 4 of the metal mold | die 2 intermittently. Furthermore, after that, the air valve 19a may be opened intermittently to supply air intermittently to the medium flow path 4 of the mold 2. Or it is good also as a structure which opens the cooling medium small quantity valve 12c and the air valve 19a alternately, and supplies the small flow volume cooling medium and air to the medium flow path 4 of the metal mold | die 2 alternately.

In this operation example, when the detected value of the temperature sensor 6 is below a predetermined threshold value (switching threshold value), the first cooling process is switched to the second cooling process. In the setting of the switching threshold and the execution control of the second cooling step, the cooling medium in the medium flow passage 4 can be almost discharged (purged) by executing the second cooling step, as described above, so that overcooling and the like do not occur. In other words, it may be set and controlled as appropriate so as not to greatly fall below the target cooling temperature at the end of the cooling step. The switching threshold may be input and set via the display operation unit 24.
In the second cooling step, steam may be supplied instead of or in addition to the air.
Also in this operation example, the pre-cooling step as described above may be executed.
Also in this operation example, after the cooling process is performed, the mold 2 is appropriately opened and the molded product is taken out, and the heating process and the cooling process are repeatedly performed.
Also in the mold cooling system (mold heating / cooling system) 1A and the mold cooling method (mold heating / cooling method) executed by using the mold cooling system (mold heating / cooling system) according to the present embodiment, the first embodiment and the operation example thereof. The effect is almost the same.

Next, an example of a mold cooling system according to still another embodiment of the present invention and an example of a mold cooling method executed using the mold cooling system will be described.
FIG. 5 is an explanatory diagram for explaining a mold cooling system and a mold cooling method executed using the mold cooling system according to the third embodiment.
Note that differences from the above embodiments will be mainly described, and the same components will be denoted by the same reference numerals, and description thereof will be omitted or simplified.

Also in this embodiment, the mold cooling system 1B is a mold heating / cooling system 1B that performs heating in addition to cooling of the mold 2.
In the present embodiment, the cooling path 14A for supplying the cooling medium to the low temperature side flow path of the heat exchanger 20A is not communicated with the cooling medium supply source 10 for supplying the cooling medium to the medium flow path 4 of the mold 2. In addition, the cooling medium supply source 17 for the heat exchanger 20A is communicated. With such a configuration, for example, the cooling medium supply source 17 may be a cooling tower installed in a factory or the like, and the cooling medium supply source 10 may be a storage unit or the like that is not temperature-controlled. The configuration of the cooling medium supply source 10 can be simplified.
Note that, in the mold heating / cooling system 1B according to the present embodiment as well, it is possible to perform substantially the same operation (mold heating / cooling method (mold cooling method)) as in the above-described operation examples. The effects similar to those of the embodiments and the operation examples are obtained.

The heat exchangers 20 and 20A are not limited to a mode in which a cooling medium is sent to the low-temperature side flow path and cooled, and, for example, vaporized cooling that is cooled by a fan or the like and sent to the high-temperature side flow path A configuration for condensing the medium, that is, an air-cooled type may be used.
In addition, different configurations and operations described in the above embodiments may be applied by appropriately rearranging or combining them. In this case, you may make it deform | transform suitably as needed.
Moreover, although each said embodiment has shown the example made into the aspect which connected the discharge side path | route 15 of the downstream of the heat exchangers 20 and 20A to the return side of the cooling medium supply source 10, and circulated the cooling medium. The discharge side path 15 on the downstream side of the heat exchangers 20 and 20A may be discharged as drain without being connected to the return side of the cooling medium supply source 10.

In the above embodiments, the mold heating / cooling systems 1, 1 </ b> A, and 1 </ b> B that perform heating in addition to the cooling of the mold 2 are shown, but the mold cooling system that cools the mold 2. 1, 1A, 1B may be used. In this case, a mold heating system (mold heating apparatus) for heating the mold 2 that is controlled separately from the mold cooling systems 1, 1A, 1B according to each embodiment may be provided.
Further, in each of the above operation examples, the second cooling step of supplying steam or air to the medium flow path 4 of the mold 2 after executing the first cooling process of supplying the cooling medium to the medium flow path 4 of the mold 2. However, the second cooling process may not be executed. In this case, in the cooling process, the precooling process as described above may be executed, and then the main cooling process may be executed. Further, only the main cooling process may be executed. That is, the discharge side path 15 connected to the outlet 5 side of the medium flow path 4 of the mold 2 is communicated with the heat exchangers 20 and 20A, and the vaporized cooling medium discharged from the medium flow path 4 is transferred to the heat exchanger. It is good also as a structure which drops a pressure by condensing in 20 and 20A, supplies a cooling medium effectively, and cools.

1,1A, 1B Mold heating / cooling system (mold cooling system)
2 Mold 3 Inlet 4 Medium flow path 5 Outlet 8 Steam source 9 Air source 10 Cooling medium supply source 12, 13 Supply side path 15 Discharge side path 16 Backflow prevention unit 18 Steam supply path 19 Air supply path 20, 20A Heat exchanger 22 Control unit

Claims (7)

A mold heated by a mold heater that is energized and controlled so that the temperature of the mold reaches a preset heating target temperature of 150 ° C. or higher is supplied to a cooling medium supply source in a medium flow path provided in the mold. A system for cooling by supplying a cooling medium from
The discharge side path connected to the outlet side of the medium flow path of the mold communicates with a heat exchanger for condensing the vaporized cooling medium discharged from the medium flow path, while the medium flow path of the mold A path for supplying steam or air from a steam source or an air source is connected to a supply side path from the cooling medium supply source connected to the inlet side of
In the cooling step after the heating step of heating the die to the heating target temperature by the die heater is performed, the supply of the steam or the air and the supply of the cooling medium are controlled, and the die And a controller that performs a main cooling step of supplying the cooling medium to the medium flow path of the mold after performing a pre-cooling process of supplying the steam or the air to the medium flow path of the mold. And mold cooling system. In claim 1,
A cooling path provided to be branched from the supply side path is connected to the return side of the cooling medium supply source in communication with the low temperature side flow path of the heat exchanger, and downstream of the heat exchanger The mold cooling system is characterized in that the discharge side path on the side is connected to the return medium side of the cooling medium supply source . In claim 1 or 2,
Wherein the control unit controls the supply of the steam or the air supply and the cooling medium, after to supply the cooling medium to the medium flow path of the die, the to-medium flow paths of the mold steam or mold cooling system, characterized in that make supplying the air. In any one of Claims 1 thru | or 3,
The mold cooling system according to claim 1, wherein a backflow prevention unit for preventing backflow is provided in a discharge side path downstream of the heat exchanger. Supply a cooling medium to a medium flow path provided in the mold heated by a mold heater that is energized and controlled so that the mold temperature reaches a preset heating target temperature of 150 ° C. or higher. And the method of cooling,
In the cooling step after the heating step of heating the mold so as to reach the heating target temperature by the die heater , a pre-cooling step of supplying steam or air to the medium flow path of the die was executed. Thereafter, a main cooling step of supplying the cooling medium to the medium flow path of the mold is performed, and a discharge side path connected to an outlet side of the medium flow path of the mold is communicated with a heat exchanger, A mold cooling method, wherein the vaporized cooling medium discharged from the medium flow path is condensed in the heat exchanger. In claim 5,
A cooling path provided to branch from a supply side path for supplying the cooling medium to the medium flow path of the mold is communicated with a low temperature side flow path of the heat exchanger, and the cooling medium passes through the cooling path. To the return side of the cooling medium supply source that supplies the cooling medium, and the cooling medium that has passed through the discharge path downstream of the heat exchanger is returned to the return side of the cooling medium supply source. A mold cooling method characterized by returning the medium. In claim 5 or 6,
After performing the 1st cooling process as the said main cooling process, the 2nd cooling process which supplies steam or air to the medium flow path of the said mold is performed, The metal mold cooling method characterized by the above-mentioned.

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