JP2017087440A - Temperature controls - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide temperature controls which can prevent generation of scale in a heat exchanger.SOLUTION: Temperature controls control temperature of an object by circulating medium between a pump and the object through a pipe line. The temperature controls comprise: a heat exchanger having a cooling pipe line supplying cooling water, a cooling channel interposed to the pipe line to flow the cooling water and a medium pass flowing a medium; a cooling valve interposed to the pipe line of the exit side of the heat exchanger; and a by-pass line bypassing between the pipe line of the entry side of the heat exchanger and the pipe line between the cooling valve and the pump.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a temperature control device that controls the temperature of an object by circulating a medium between a pump and the object via a pipe line.

  A mold is used in an injection molding machine for injection molding a molded product using a synthetic resin such as plastic. An injection mold has a cavity that is a space portion filled with molten plastic, and a flow path for flowing a medium for cooling and solidifying the molten plastic. Maintaining the mold temperature at the required temperature is very important for improving the accuracy of the molded product.

  Therefore, a medium pipe through which the medium passes, a medium tank, a heater for heating the medium, a heat exchanger for cooling the medium, a pump, and the like are arranged inside the casing, and the heat exchanger is connected to the medium pipe with the outer pipe. A mold temperature control device is disclosed in which a cooling pipe through which cooling water passes is formed as a double pipe inserted as an inner pipe, and this double pipe is formed in a coil shape (see Patent Document 1). ).

JP 2007-7950 A

  However, in the mold temperature control apparatus described in Patent Document 1, a cooling pipe (primary side pipe) is formed by always flowing a medium through the medium pipe (secondary side pipe) of the heat exchanger and opening and closing a predetermined valve. ) To adjust the temperature of the medium by controlling the cooling water flowing to the medium. Thereby, the temperature of the heat exchange part becomes a temperature close to the high temperature of the medium. For this reason, in the heat exchanger, when heat is exchanged between the cooling water during cooling and the high-temperature heat exchanging part and the cooling water is drained in the open air state, the cooling water becomes below the saturated steam pressure, As the portion evaporates, a scale is generated in which insoluble components in the cooling water adhere to and accumulate on the cooling pipe in the heat exchanger. If scale adheres to and accumulates on the cooling pipe, there is a problem that the heat exchange rate decreases and the operating cost increases. Moreover, it is necessary to perform maintenance of a heat exchanger frequently.

  This invention is made | formed in view of such a situation, and it aims at providing the temperature control apparatus which can suppress generation | occurrence | production of the scale in a heat exchanger.

  A temperature control device according to the present invention communicates with a cooling pipe that supplies cooling water in a temperature control device that controls the temperature of the target by circulating a medium between a pump and the target through a pipe. A heat exchanger having a cooling flow path and a medium flow path that communicates with the pipe and allows the medium to flow, a cooling valve interposed in the pipe on the outlet side of the heat exchanger, and the heat exchanger And a bypass pipe that bypasses between the pipe on the inlet side and the pipe between the cooling valve and the pump.

  In the present invention, the temperature control device includes a cooling channel that communicates with a cooling channel that supplies cooling water and a medium channel that communicates with the channel and allows a medium to flow, and an outlet side of the heat exchanger. And a bypass pipe that bypasses between the cooling valve interposed in the pipe line and the pipe line between the inlet side of the heat exchanger and the pipe line between the cooling valve and the pump.

  That is, when the cooling valve is closed, the medium sent from the outlet side of the pump flows to the object (for example, a mold) through the pipe line, and the medium flowing out from the object passes through the pipe through the bypass pipe. Follow the path and return to the pump. The temperature of the medium flowing through the object is relatively high, for example, 180 ° C., but is not limited thereto. The medium in the medium flow path of the heat exchanger is not circulated because the cooling valve is closed, and the cooling water in the cooling flow path (for example, 20 ° C., but is not limited thereto). It is heat exchanged and adjusted to a relatively low temperature (eg, but not limited to 80 ° C.) below the temperature of the medium.

  When the temperature of the object rises (for example, when the molten plastic is filled in the mold, the temperature of the mold rises) and the temperature of the medium rises (for example, exceeds 180 ° C.), the cooling valve Is opened, the medium in the medium flow path of the heat exchanger circulates in the pipe line, and the temperature of the medium is lowered. Since the heat exchanger medium is not always circulating, the temperature of the heat exchanger does not rise to the medium temperature. For this reason, since the temperature difference between the cooling water of the heat exchanger and the medium in the medium flow path is, for example, 60 ° C. (= 80 ° C.−20 ° C.), the cooling water of the heat exchanger and the medium in the pipe line The temperature difference is remarkably small compared to 160 ° C. (= 180 ° C.−20 ° C.), which is the temperature difference between For this reason, since it is possible to suppress the evaporation of a part of the cooling water in the cooling flow path of the heat exchanger, it is possible to suppress the insoluble components contained in the cooling water from adhering to and accumulating in the cooling flow path. , Generation of scale can be suppressed. Moreover, since generation | occurrence | production of the scale in a heat exchanger can be suppressed, it is not necessary to maintain a heat exchanger frequently.

  The temperature control device according to the present invention includes a medium temperature detection unit that detects the temperature of the medium, and a cooling valve control unit that controls opening and closing of the cooling valve based on the temperature detected by the medium temperature detection unit. It is characterized by.

  In the present invention, the medium temperature detection unit detects the temperature of the medium. The cooling valve control unit controls opening and closing of the cooling valve based on the temperature detected by the medium temperature detection unit.

  In other words, when the temperature detected by the medium temperature detection unit exceeds a required temperature (for example, 180 ° C.), the cooling valve control unit opens the cooling valve, so that the inside of the medium flow path cooled by the heat exchanger The medium circulates in the pipeline and the temperature of the medium can be lowered.

  The temperature control device according to the present invention is characterized in that the cooling valve control unit opens and closes the cooling valve based on the temperature detected by the medium temperature detection unit every predetermined control cycle.

  In the present invention, the cooling valve control unit opens and closes the cooling valve based on the temperature detected by the medium temperature detection unit every predetermined control cycle. For example, the higher the temperature detected by the medium temperature detection unit, the longer the time until the cooling valve is closed (that is, the longer the time during which the cooling valve is open). Thereby, the temperature of the medium can be controlled to a required temperature.

  The temperature control apparatus according to the present invention includes a temperature adjusting unit that adjusts the temperature of the medium flow path to be within a predetermined range.

  In the present invention, the temperature adjustment unit adjusts the temperature of the medium flow path in the heat exchanger so as to be within a predetermined range. For example, the temperature adjustment unit adjusts the temperature of the medium flow path in the heat exchanger so as to be within a predetermined range when the cooling valve is not opened and closed. The case where the cooling valve is not opened or closed refers to a state where the cooling valve is closed without having to repeatedly open and close the cooling valve one or more times in order to cool the medium. Even in a state where the cooling valve is opened and closed, the temperature adjustment unit may perform an operation to adjust the temperature of the medium flow path in the heat exchanger to be within a predetermined range. The predetermined range is, for example, a relatively low temperature lower than the temperature of the medium and higher than the temperature of the cooling water, and can be, for example, about 80 ° C. ± 5 ° C., but is not limited thereto. It may be about 60 ° C. ± 5 ° C. instead. Accordingly, when the temperature of the medium is a required temperature (for example, 180 ° C.) and the cooling valve is not opened and closed, for example, the medium flow path of the heat exchanger is circulated while circulating the medium through the bypass line. The inside medium can be maintained at a relatively low temperature without being circulated.

  The temperature control device according to the present invention includes a cooling water valve interposed in the cooling pipe line, and the temperature adjusting unit opens and closes the cooling water valve at a predetermined timing so that the temperature of the medium flow path is predetermined. It is characterized by adjusting to be within the range.

  In the present invention, the cooling water valve provided in the cooling pipe is provided, and the temperature adjusting unit opens and closes the cooling water valve at a predetermined timing so that the temperature of the medium flow path is within a predetermined range. Adjust. The predetermined timing can be set in advance based on, for example, the volume of the medium flow path of the heat exchanger, the predetermined range of the temperature of the medium flow path, and the like.

  That is, by opening and closing the cooling water valve at a predetermined timing, the cooling water can flow intermittently through the cooling flow path of the heat exchanger, exchanging heat with the medium in the medium flow path, and the temperature of the medium flow path Can be adjusted to be within a predetermined range. As a result, the temperature of the cooling water flowing through the heat exchanger does not increase and can be kept at a relatively low temperature of about 80 ° C., and the temperature of the cooling water becomes equal to or lower than the saturation temperature. Can be prevented.

  The temperature control device according to the present invention includes a cooling water valve interposed in the cooling pipe, and a flow path temperature detection unit that detects a temperature of the medium flow path, and the temperature adjustment unit includes the flow path Based on the temperature detected by the temperature detector, the cooling water valve is opened and closed to adjust the temperature of the medium flow path to be within a predetermined range.

  In the present invention, a cooling water valve interposed in the cooling pipe and a flow path temperature detecting unit for detecting the temperature of the medium flow path are provided, and the temperature adjusting unit is a temperature detected by the flow path temperature detecting unit. Based on the above, the cooling water valve is opened and closed to adjust the temperature of the medium flow path to be within a predetermined range. Detecting the temperature of the medium flow path of the heat exchanger with the flow path temperature detecting unit means detecting the temperature of the pipe line on the downstream side (outlet side of the medium) of the heat exchanger communicating with the medium flow path of the heat exchanger. Including.

  That is, the cooling water valve is opened and closed so that the temperature detected by the flow path temperature detection unit is within a predetermined range. Thereby, the cooling water can flow intermittently through the cooling flow path of the heat exchanger, and heat exchange with the medium in the medium flow path can be performed so that the temperature of the medium flow path falls within a predetermined range. it can. As a result, the temperature of the cooling water flowing through the heat exchanger does not increase and can be kept at a relatively low temperature of about 80 ° C., and the temperature of the cooling water becomes equal to or lower than the saturation temperature. Can be prevented.

  According to this invention, generation | occurrence | production of the scale in a heat exchanger can be suppressed.

It is explanatory drawing which shows an example of a structure of the metal mold | die temperature controller as a temperature control apparatus of this Embodiment. It is a time chart which shows an example of operation | movement of the metal mold | die temperature controller of this Embodiment. It is a flowchart which shows an example of the process sequence at the time of the heating control of the metal mold | die temperature controller of this Embodiment. It is a flowchart which shows an example of the process sequence at the time of cooling control of the metal mold | die temperature controller of this Embodiment.

  Hereinafter, the present invention will be described with reference to the drawings illustrating embodiments thereof. FIG. 1 is an explanatory diagram showing an example of the configuration of a mold temperature controller 100 as a temperature control device of the present embodiment. In the present embodiment, the mold temperature controller 100 will be described as an example of the temperature controller, but the temperature controller is not limited to the mold temperature controller. The mold temperature controller 100 adjusts (controls) the temperature of the mold 200 as an object, more specifically, the temperature of the cooling medium supplied to the mold 200.

  As shown in FIG. 1, the mold temperature controller 100 connects the pipe line 11 (medium feed pipe line) between the outlet side (OUT) of the pump 31 and the inlet side of the mold 200. Is connected between the outlet side of the pump 31 and the inlet side (IN) of the pump 31, and the medium (for example, water) is supplied to the pipes 11 and 12 and the bypass pipe 16 by the pump 31. It has come to circulate. That is, for example, the pump 31 rotates the impeller at high speed in the casing by the rotation of the motor and uses the centrifugal force acting on the medium, so that the medium circulates through the pipelines 11 and 12 and the bypass pipeline 16.

  A pressure sensor 62 is provided in the vicinity of the outlet side of the pump 31 in the pipe line 11 so that the pressure of the medium near the outlet side of the pump 31 can be measured. A heater unit 80 is interposed in the middle of the pipe line 11, and the temperature of the medium can be raised by heating the medium. The thermostat 81 stops heating by the heater unit 80 when the heater unit 80 exceeds a predetermined temperature. Further, the pipe 11 is provided with a temperature sensor 71 as a medium temperature detector, and the temperature of the medium in the pipe 11 can be detected.

  The pipeline 11 is branched into two systems in the middle, and each branched pipeline 11 is connected to the inlet side of the mold 200. Each of the branched pipelines 11 is provided with a medium delivery valve 21 so that the flow rate of the medium for each branched pipeline 11 can be adjusted. Similarly, the pipeline 12 is also branched into two systems on the outlet side of the mold 200, and the pipeline 12 branched in the middle is integrated into one pipeline 12. Each branched pipe 12 is provided with a return valve 22, and the flow rate of the medium for each branched pipe 12 can be adjusted.

  A heat exchanger 40 is provided in the middle of the pipe 12, and a cooling electromagnetic valve 23 as a cooling valve is provided in the pipe 12 on the outlet side of the heat exchanger 40. Further, a required portion of the conduit 12 on the inlet side of the heat exchanger 40 (a portion indicated by a symbol A in FIG. 1, also referred to as a branch point A) and a required portion of the conduit 12 on the outlet side of the cooling electromagnetic valve 23 (see FIG. A bypass pipe line 16 is provided between the point B and the branch point B). For convenience, the pipe 12 has a pipe 12a between the branch point A and the heat exchanger 40, a pipe 12b between the heat exchanger 40 and the cooling electromagnetic valve 23, and the cooling electromagnetic valve 23. A space between the branch point B is referred to as a pipe line 12c.

  The heat exchanger 40 has a cooling flow path 13a for flowing cooling water on the primary side and a medium flow path 12d for flowing medium on the secondary side. One end of the medium flow path 12 communicates with the pipe line 12a, and the other end of the medium flow path 12 communicates with the pipe line 12b. The heat exchanger 40 performs heat exchange between the cooling water flowing through the cooling flow path 13a and the medium flowing through the medium flow path 12d, and cools the medium flowing through the medium flow path 12d to adjust the temperature.

  In addition, a temperature sensor 72 as a flow path temperature detecting unit is provided at a predetermined location of the pipe line 12b. The temperature sensor 72 detects the temperature of the medium in the medium flow path 12d of the heat exchanger 40. Note that the temperature sensor 72 detects the temperature of the medium flow path 12d of the heat exchanger 40 is a pipe line on the downstream side (media outlet side) of the heat exchanger 40 communicating with the medium flow path 12 of the heat exchanger 40. It also includes detecting the temperature of 12b. In FIG. 1, the temperature sensor 72 is illustrated as being provided in the middle of the pipe line 12 b, but actually, the temperature sensor 72 is provided between the medium flow path 12 d and the pipe line 12 b of the heat exchanger 40. The temperature sensor 72 is provided in the vicinity of the connection location so that the temperature of the medium in the medium flow path 12d of the heat exchanger 40 can be detected. Note that detecting the temperature of the medium in the medium flow path 12d by the temperature sensor 72 includes detecting the temperature of the medium in the pipe line 12b. In particular, when the cooling electromagnetic valve 23 is closed, the medium in the medium flow path 12d and the pipe 12b does not circulate. Therefore, even if the temperature sensor 72 is provided in the pipe 12b, the temperature of the medium in the medium flow path 12d can be detected. Can do. Moreover, both ends of the cooling flow path 13a are connected with the cooling pipe line 13 which supplies cooling water.

  A pressure sensor 63 and an open relief valve are provided in the vicinity of the inlet side of the pump 31 in the pipe line 12. The pressure sensor 63 measures the pressure of the medium near the inlet side of the pump 31. In addition, a strainer is provided on the pipe 12 on the inlet side of the heat exchanger 40 (upstream from the branch point A). The strainer removes solid components contained in the medium.

  A pipe 14 is provided between the water supply port and the branch point B of the pipe 12. A strainer and a pressure sensor 61 are provided on the water supply port side of the pipeline 14. The pressure sensor 61 measures the feed water pressure. A check valve 26 is interposed in the middle of the pipe line 14, and a branch pipe 14 a having a pressurizing pump 32 is connected to both sides of the check valve 26.

  The pressurizing pump 32 pressurizes so that the pressure of the medium (for example, water) in the pipe lines 11 and 12 and the bypass pipe line 16 becomes higher than the saturated vapor pressure.

  A cooling pipe 13 for branching the cooling water and flowing it to the heat exchanger 40 is connected to the upstream side of the pipe 14 where the branch pipe 14 a is connected. The cooling conduit 13 is connected to one end of the cooling passage 13 a on the inlet side of the heat exchanger 40. The cooling pipe line 13 connected to the other end of the cooling flow path 13a on the outlet side of the heat exchanger 40 is connected to the drain outlet. A cooling water electromagnetic valve 25 as a cooling water valve is interposed in the middle of the cooling pipe line 13 connected to the drain outlet.

  Further, a drain line 15 connected to a drain port is connected to the pipe line 12b between the temperature sensor 72 and the cooling electromagnetic valve 23. A drain electromagnetic valve 24 is interposed in the middle of the drain pipe 15.

  The mold temperature controller 100 includes a temperature controller 50, and the temperature controller 50 includes a valve opening / closing controller 51, a heat exchanger temperature controller 52, and the like. The temperature control unit 50 can acquire the temperatures detected by the temperature sensors 71 and 72.

  The valve opening / closing control unit 51 controls the opening / closing of the cooling electromagnetic valve 23, the drain electromagnetic valve 24, and the cooling water electromagnetic valve 25. The heat exchanger temperature adjusting unit 52 adjusts the temperature of the medium in the cooling flow path 12d of the heat exchanger 40.

  The outline of the operation of the mold temperature controller 100 is as follows. When the drainage electromagnetic valve 24, the cooling electromagnetic valve 23, the medium sending valve 21, and the medium return valve 22 are opened and water as a medium is supplied from the water supply port, the water in the circulation path such as the pipes 11 and 12 and the bypass pipe 16 is provided. The air is completely exhausted, and then the drainage electromagnetic valve 24 is closed to fill the circulation paths such as the pipelines 11 and 12 and the bypass pipeline 16 with the medium. Further, the pressure of the medium in the circulation path such as the pipes 11 and 12 and the bypass pipe 16 is maintained by the pressurizing pump 32 to be equal to or higher than the saturated vapor pressure corresponding to the medium temperature. The temperature of the medium in the circulation paths such as the pipelines 11 and 12 and the bypass pipeline 16 is increased by the heater unit 80 so as to reach a required temperature. Further, the temperature of the medium in the circulation path such as the bypass pipe line 16 is cooled by the heat exchanger 40 so as to become a required temperature. By the heating operation by the heater unit 80 and the cooling operation by the heat exchanger 40, the temperature of the medium in the circulation paths such as the pipelines 11 and 12 and the bypass pipeline 16, that is, the temperature of the medium in the mold 200 becomes a required temperature. Regulated (controlled).

  Hereinafter, the mold temperature controller 100 will be described in detail.

  As described above, the mold temperature controller 100 according to the present embodiment includes the cooling channel 13a and the channel that are interposed in the cooling channel 13 and the channel 12 for supplying cooling water and communicate with the cooling channel 13. 12, a heat exchanger 40 having a medium flow path 12d through which the medium flows, and a cooling electromagnetic wave interposed in the pipe 12 on the outlet side of the heat exchanger 40 (between management 12b and 12c in FIG. 1) Valve 23 (cooling valve), bypass pipe that bypasses between the pipe line 12 (branch point A) on the inlet side of the heat exchanger 40 and the pipe line 12 (branch point B) between the cooling electromagnetic valve 23 and the pump 31 A path 16 is provided.

  That is, when the cooling electromagnetic valve 23 is closed under the control of the valve opening / closing control unit 51, the medium sent from the outlet side of the pump 31 flows to the mold 200 through the pipe line 11, and from the mold 200. The discharged medium flows through the bypass line 16 through the pipe line 12 and returns to the pump 31. The temperature of the medium flowing through the mold 200 is relatively high, for example, 180 ° C., but is not limited to this.

  The medium in the medium flow path 12 of the heat exchanger 40 is not circulated because the cooling electromagnetic valve 23 is closed, and the cooling water in the cooling flow path 13a (for example, 20 ° C., but is not limited thereto). The temperature of the medium is adjusted to a relatively low temperature lower than the temperature of the medium (for example, 80 ° C., but is not limited thereto, and may be, for example, about 60 ° C.).

  When the molten plastic is filled in the mold 200 in the injection molding cycle, the temperature of the mold 200 rises and the temperature of the medium rises. For example, when the temperature of the medium exceeds a required temperature of 180 ° C., the medium in the medium flow path 12d of the heat exchanger 40 circulates in the pipe lines 12 and 11 by opening the cooling electromagnetic valve 23. The temperature of the medium can be lowered.

  The temperature difference between the cooling water of the heat exchanger 40 and the medium in the medium flow path 12d is, for example, 60 ° C. (= 80 ° C.−20 ° C.). On the other hand, in the case of a conventional mold temperature controller, since all of the medium in the circulation path flows through the secondary side flow path of the heat exchanger, the temperature of the cooling water of the heat exchanger (for example, 20 ° C.) The temperature difference from the temperature of the medium in the flow path (for example, 180 ° C.) is about 160 ° C.

  That is, the temperature difference (for example, 60 ° C.) between the primary side cooling flow path 13a and the secondary side medium flow path 12d in the heat exchanger 40 in the mold temperature controller 100 of the present embodiment has been conventionally This is significantly smaller than the case of. For this reason, since it can suppress that a part of cooling water in the cooling flow path 13a of the primary side of a heat exchanger evaporates, the insoluble component contained in cooling water adheres and accumulates on the cooling flow path 13a. It is possible to suppress the generation of scale. And the problem that a heat exchange rate falls and an operating cost increases can be eliminated. Moreover, since generation | occurrence | production of the scale in the heat exchanger 40 can be suppressed, it is not necessary to maintain the heat exchanger 40 frequently.

  The temperature sensor 71 detects the temperature of the medium in the pipe line 11. The valve opening / closing control unit 11 has a function as a cooling valve control unit, and controls the opening / closing of the cooling electromagnetic valve 23 based on the temperature detected by the temperature sensor 71.

  That is, when the temperature of the medium detected by the temperature sensor 71 exceeds a required temperature (for example, 180 ° C.), the valve opening / closing control unit 51 is cooled by the heat exchanger 40 by opening the cooling electromagnetic valve 23. The medium in the medium flow path 12d circulates in the pipe lines 12 and 11, and the temperature of the medium can be lowered. The volume of the medium flow path 12d of the heat exchanger 40 can be approximately 10 to 20% of the total volume of the circulation paths such as the pipe lines 11 and 12 and the bypass pipe line 16, and circulates in the medium flow path 12d. The medium cooled without circulating through the pipes 12 and 11 can reduce the temperature of the medium. Note that the volume of the medium flow path 12d is not limited to the above-described 10 to 20%.

  Further, the valve opening / closing control unit 51 opens and closes the cooling electromagnetic valve 23 based on the temperature detected by the temperature sensor 71 at every predetermined control cycle. For example, the time until the cooling electromagnetic valve 23 is closed is increased as the temperature detected by the temperature sensor 71 is higher (that is, the time during which the cooling electromagnetic valve 23 is opened is increased). Thereby, the temperature of the medium can be controlled to a required temperature.

  The heat exchanger temperature adjusting unit 52 has a function as a temperature adjusting unit, and adjusts the temperature of the medium flow path 12d in the heat exchanger 40 to be within a predetermined range. For example, the heat exchanger temperature adjustment unit 52 adjusts the temperature of the medium flow path 12d in the heat exchanger 40 to be within a predetermined range when the cooling electromagnetic valve 23 is not opened and closed. The case where the cooling electromagnetic valve 23 is not opened or closed refers to a state where the cooling electromagnetic valve 23 is closed without having to repeatedly open and close the cooling electromagnetic valve 23 one or more times in order to cool the medium. Even when the cooling electromagnetic valve 23 is opened and closed, the heat exchanger temperature adjusting unit 52 operates to adjust the temperature of the medium flow path 12d in the heat exchanger 40 to be within a predetermined range. May be. The predetermined range is, for example, a relatively low temperature lower than the temperature of the medium and higher than the temperature of the cooling water, and can be, for example, about 80 ° C. ± 5 ° C., but is not limited thereto. It may be about 60 ° C. ± 5 ° C. instead.

  Thereby, when the temperature of the medium circulating through the pipelines 11 and 12 and the bypass pipeline 16 is a required temperature (for example, 180 ° C.) and the cooling electromagnetic valve 23 is not opened and closed, for example, While the medium is circulated through the path 16, the medium in the medium flow path 12 d of the heat exchanger 40 can be maintained at a relatively low temperature without being circulated.

  For example, there are two methods for adjusting the temperature by the heat exchanger temperature adjusting unit 52. In the first method, the heat exchanger temperature adjusting unit 52 operates the valve opening / closing control unit 51 to open and close the cooling water electromagnetic valve 25 at a predetermined timing, and intermittently connects to the cooling flow path 13a of the heat exchanger 40. Then, cooling water is flowed to adjust the temperature of the medium flow path 12d to be within a predetermined range. The predetermined timing can be set in advance based on, for example, the volume of the medium flow path 12d of the heat exchanger 40, the predetermined range of the temperature of the medium flow path 12d, and the like.

  That is, by opening and closing the cooling water electromagnetic valve 25 at a predetermined timing, the cooling water can be intermittently flowed into the cooling flow path 13a of the heat exchanger 40, and heat exchange with the medium in the medium flow path 12d is performed. The temperature of the medium flow path 12d can be adjusted to be within a predetermined range. As a result, the temperature of the cooling water flowing through the heat exchanger 40 does not increase and can be kept at a relatively low temperature of about 80 ° C., and the temperature of the cooling water becomes equal to or lower than the saturation temperature. Can be prevented.

  In the second method, the heat exchanger temperature adjusting unit 52 operates the valve opening / closing control unit 51 to open and close the cooling water electromagnetic valve 25 based on the temperature detected by the temperature sensor 72, thereby causing the temperature of the medium flow path 12d. Is adjusted to be within a predetermined range.

  That is, the cooling water solenoid valve 25 is opened and closed so that the temperature detected by the temperature sensor 72 is within a predetermined range. As a result, the cooling water can be intermittently passed through the cooling flow path 13a of the heat exchanger 40, and heat exchange with the medium of the medium flow path 12d is performed so that the temperature of the medium flow path 12d is within a predetermined range. Can be adjusted. As a result, the temperature of the cooling water flowing through the heat exchanger 40 does not increase and can be kept at a relatively low temperature of about 80 ° C., and the temperature of the cooling water becomes equal to or lower than the saturation temperature. Can be prevented. When using the first method described above, the temperature sensor 72 may not be provided.

  FIG. 2 is a time chart showing an example of the operation of the mold temperature controller 100 of the present embodiment. FIG. 2 shows the temperature of the medium and the medium in the heat exchanger (the temperature of the medium flow path 12d), the operating state of the pump 31, the operating state of the heater unit 80, the drainage electromagnetic wave in order from the upper chart to the lower chart. The operation state of the valve 24, the operation state of the cooling electromagnetic valve 23, and the operation state of the cooling water electromagnetic valve 25 are shown. In FIG. 2, the horizontal axis indicates time, and in the order from left to right, a chart at the time of heating control, cooling control, and stability is shown.

  First, at the time of heating control, the pump 31 is in an operating state, and the drain electromagnetic valve 24, the cooling electromagnetic valve 23, and the cooling water electromagnetic valve 25 are in a stopped state. The heater unit 80 operates at a predetermined cycle. That is, the heating operation by the heater unit 80 is intermittently performed, and the temperature of the medium is increased so as to reach a required temperature (for example, 180 ° C.).

  When it is time to open the cooling water solenoid valve 25 (time t1 in FIG. 2), the cooling water solenoid valve 25 is opened for a predetermined time. By opening the cooling water electromagnetic valve 25 for a predetermined time, the cooling water flows into the cooling flow path 13a of the heat exchanger 40, and the temperature of the medium flow path 12d of the heat exchanger 40 is set to a required temperature (for example, 80 ° C.). Can be maintained. If the cooling water electromagnetic valve 25 is kept closed without being opened for a predetermined time, the medium temperature in the heat exchanger 40 rises beyond a required temperature as shown by the broken line in FIG.

  Next, at the time of cooling control, the pump 31 is in an operating state, and the drain electromagnetic valve 24, the cooling electromagnetic valve 23, and the cooling water electromagnetic valve 25 are in a stopped state. When it is time to open the cooling water solenoid valve 25 (time t2 in FIG. 2), the cooling water solenoid valve 25 is opened for a predetermined time. Thereby, the temperature of the medium flow path 12d of the heat exchanger 40 is maintained at a required temperature (for example, 80 ° C.).

  Then, the mold 200 is filled with molten plastic, the mold temperature rises, and the medium temperature rises. When the temperature of the medium exceeds an upper limit value (for example, but not limited to 181 ° C.), the opening / closing operation of the cooling electromagnetic valve 23 is started (time t3 in FIG. 2). The medium maintained at a relatively low required temperature in the medium flow path 12d of the heat exchanger 40 by opening only for the required time flows through the pipes 12 and 11 and the bypass pipe 16, so that the temperature of the medium is increased. Lower.

  Further, since the high temperature medium flows into the medium flow path 12d of the heat exchanger 40 by opening the cooling electromagnetic valve 23, the cooling water electromagnetic valve 25 is opened for a required time in order to lower the medium temperature in the heat exchanger 40. As a result, the cooling water is caused to flow through the cooling flow path 13a. The opening / closing operations of the cooling electromagnetic valve 23 and the cooling water electromagnetic valve 25 are repeated until the medium temperature falls below the upper limit value (time t4 in FIG. 2).

  Further, at the stable time when it is not necessary to perform heating control and cooling control, the pump 31 is in an operating state, and the heater unit 80, the drain electromagnetic valve 24, the cooling electromagnetic valve 23, and the cooling water electromagnetic valve 25 are in a stopped state. When it is time to open the cooling water solenoid valve 25 (time t5, t6 in FIG. 2), the cooling water solenoid valve 25 is opened for a predetermined time. By opening the cooling water electromagnetic valve 25 for a predetermined time, the cooling water flows into the cooling flow path 13a of the heat exchanger 40, and the temperature of the medium flow path 12d of the heat exchanger 40 is set to a required temperature (for example, 80 ° C.). Can be maintained.

  FIG. 3 is a flowchart showing an example of a processing procedure at the time of heating control of the mold temperature controller 100 of the present embodiment. Hereinafter, for the sake of convenience, the subject of processing will be described as the temperature controller 50. The temperature control unit 50 closes the drain electromagnetic valve 24 (S11), closes the cooling electromagnetic valve 23 (S12), and closes the cooling water electromagnetic valve 25 (S13). The temperature controller 50 operates the heater unit 80 at a predetermined cycle (S14).

  The temperature controller 50 determines whether or not it is time to open the cooling water solenoid valve 25 (S15). If it is time to open the cooling water solenoid valve 25 (YES in S15), the temperature control unit 50 sets the cooling water solenoid valve 25 to a predetermined value. Open only for a time (S16). When it is not time to open the cooling water solenoid valve 25 (NO in S15), the temperature control unit 50 performs the process of step S17 described later without performing the process of step S16.

  The temperature control unit 50 determines whether or not to end the process (S17). If the process is not ended (NO in S17), the process after step S15 is continued and the process is ended (YES in S17). The process ends.

  FIG. 4 is a flowchart showing an example of a processing procedure during cooling control of the mold temperature controller 100 of the present embodiment. The temperature control unit 50 closes the drain electromagnetic valve 24 (S31), closes the cooling electromagnetic valve 23 (S32), and closes the cooling water electromagnetic valve 25 (S33). The temperature control unit 50 determines whether it is time to open the coolant electromagnetic valve 25 (S34).

  When it is time to open the cooling water solenoid valve 25 (YES in S34), the temperature control unit 50 opens the cooling water solenoid valve 25 for a predetermined time (S35). If it is not time to open the cooling water solenoid valve 25 (NO in S34), the temperature control unit 50 performs the process of step S36 described later without performing the process of step S35.

  The temperature controller 50 detects the temperature of the medium by the temperature sensor 71 (S36), and determines whether or not the detected temperature of the medium exceeds the upper limit value (S37). When the detected temperature of the medium exceeds the upper limit value (YES in S37), the temperature control unit 50 opens the cooling electromagnetic valve 23 for a predetermined time (S38) and opens the cooling water electromagnetic valve 25 for a predetermined time (S39). . When the detected temperature of the medium does not exceed the upper limit value (NO in S37), the temperature control unit 50 performs the process of step S40 described later without performing the processes of steps S38 and S39.

  The temperature control unit 50 determines whether or not to end the process (S40). If the process is not ended (NO in S40), the process after step S34 is continued and the process is ended (YES in S40). The process ends.

  In the above-described embodiment, water can be used as the medium, but oil can also be used instead of water.

  In the above-described embodiment, the mold temperature controller has been described as an example of the temperature control device. However, the temperature control device is not limited to the mold temperature controller, and heat exchange of the medium (for example, heat The present embodiment can be applied to any device provided with an exchanger or the like.

  Note that at least a part of the above-described embodiments can be arbitrarily combined.

11, 12, 12a, 12b, 12c, 14 Pipe line 12d Medium flow path 13 Cooling pipe line 13a Cooling flow path 14a Branch pipe 15 Drain pipe line 16 Bypass pipe line 21 Transmission valve 22 Return valve 23 Cooling electromagnetic valve (cooling) valve)
24 Drainage solenoid valve 25 Cooling water solenoid valve (cooling water valve)
26 Check Valve 31 Pump 32 Pressure Pump 40 Heat Exchanger 50 Temperature Control Unit 51 Valve Open / Close Control Unit (Cooling Valve Control Unit)
52 Heat exchanger temperature controller (temperature controller)
61, 62, 63 Pressure sensor 71 Temperature sensor (medium temperature detector)
72 Temperature sensor (channel temperature detector)
80 Heater unit 81 Thermostat 100 Mold temperature controller (temperature control device)
200 Mold (object)

Claims (6)

In a temperature control device for controlling the temperature of an object by circulating a medium between a pump and the object via a pipeline,
A heat exchanger having a cooling flow path communicating with a cooling pipe supplying cooling water and a medium flow path communicating with the pipe and flowing the medium;
A cooling valve interposed in the conduit on the outlet side of the heat exchanger;
A temperature control device comprising: a bypass pipe that bypasses between the pipe on the inlet side of the heat exchanger and the pipe between the cooling valve and the pump. A medium temperature detector for detecting the temperature of the medium;
The temperature control device according to claim 1, further comprising: a cooling valve control unit that controls opening and closing of the cooling valve based on the temperature detected by the medium temperature detection unit. The cooling valve controller is
3. The temperature control device according to claim 2, wherein the cooling valve is opened and closed based on the temperature detected by the medium temperature detection unit every predetermined control cycle.   The temperature control device according to any one of claims 1 to 3, further comprising a temperature adjusting unit that adjusts the temperature of the medium flow path to be within a predetermined range. A cooling water valve interposed in the cooling pipe,
The temperature control unit is
The temperature control device according to claim 4, wherein the temperature of the medium flow path is adjusted to be within a predetermined range by opening and closing the cooling water valve at a predetermined timing. A cooling water valve interposed in the cooling pipe;
A flow path temperature detection unit for detecting the temperature of the medium flow path,
The temperature control unit is
The temperature control according to claim 4, wherein the temperature of the medium flow path is adjusted to be within a predetermined range by opening and closing the cooling water valve based on the temperature detected by the flow path temperature detection unit. apparatus.

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