Dual-system liquid temperature control device

Abstract

To provide a dual-system liquid temperature control device that is reducible in running cost with a simple structure.SOLUTION: A dual-system liquid temperature control device 100 comprises: a refrigeration cycle 10 which has a first condenser 12, a second condenser 13 and an evaporator 15; a high temperature-side refrigerant circulation path 30 which circulates a high temperature-side refrigerant; a first temperature measuring instrument 32 which is arranged downstream from the first condenser 12 in the high temperature-side refrigerant circulation path 30; a bypass path 33 which connects the upstream side of the first condenser 12 in the high temperature-side refrigerant circulation path 30 to the upstream side of the first temperature measuring instrument 32 on the downstream side of the first condenser 12; a low temperature-side refrigerant circulation path 40 which circulates a low temperature-side refrigerant; and a flow dividing valve 34 which divides the high temperature-side refrigerant to the high temperature-side refrigerant circulation path 30 and the bypass path 33; and an operation control part 70, wherein the operation control part 70 causes the first condenser 12 to exchange heat when a high temperature-side refrigerant temperature measurement value is less than a high temperature-side set temperature, and divides the high temperature-side refrigerant to the bypass path 33 when the high temperature-side refrigerant temperature measurement value becomes the high temperature-side set temperature or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dual-system liquid temperature adjustment device, and more particularly to a dual-system liquid temperature adjustment device that supplies two systems of low-temperature and high-temperature liquid to an object. [Background technology]

[0002] There is a dual-system liquid temperature control device for supplying two types of liquid (cooling water) with different temperatures to load equipment. A known example of such a dual-system liquid temperature control device is the configuration disclosed in Patent Document 1 (JP 2017-205773 A). The dual-system liquid temperature control device disclosed in Patent Document 1 is configured to generate two types of cooling water with different temperatures. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-205773 A (0022-0027, 0045-0047, Fig. 5, etc.) Summary of the Invention [Problem to be solved by the invention]

[0004] In the two-system liquid temperature control device disclosed in Patent Document 1, when providing two types of cooling water with different temperatures, a heater is used to heat the cooling water when the device is started up, so if one of the cooling waters is hot, there is a problem in that the running costs for producing the cooling water become high. [Means for solving the problem]

[0005] The present invention is therefore intended to solve the above problems, and has the following object: To provide a two-system liquid temperature control device that can reduce running costs by actively utilizing waste heat in the refrigeration cycle to minimize the amount of heater usage when heating the high-temperature liquid.

[0006] As a result of intensive research by the inventors to solve the above problems, the inventors have come up with the following configuration: That is, the present invention comprises a refrigeration cycle having a compressor, a first condenser, a second condenser, an expansion valve, and an evaporator, and circulating a refrigeration cycle refrigerant, a high-temperature side liquid circulation path for circulating a high-temperature side liquid between at least the first condenser and a high-temperature side temperature adjustment unit, a low-temperature side liquid circulation path for circulating a low-temperature side liquid between at least the evaporator and a low-temperature side temperature adjustment unit, a first temperature measuring device disposed downstream of the first condenser in the high-temperature side liquid circulation path and measuring the temperature of the high-temperature side liquid, a bypass path provided in the high-temperature side liquid circulation path, connecting the upstream side of the first condenser with a position downstream of the first condenser and upstream of the first temperature measuring device, and bypassing the first condenser, and an upstream connector of the bypass path in the high-temperature side liquid circulation path. and an operation control unit that controls the operation of at least the diverter valve, wherein when a first measurement value measured by the first temperature measuring device is less than a predetermined high-temperature side set temperature, the operation control unit controls the diverter valve to perform a process of heat exchange in the first condenser for a predetermined first volume of the total volume of the high-temperature side liquid, and when the first measurement value becomes equal to or greater than the high-temperature side set temperature, the operation control unit controls the diverter valve so that the first measurement value maintains the high-temperature side set temperature, and performs a process of diverting a predetermined second volume of the total volume of the high-temperature side liquid to the bypass path.

[0007] This allows the waste heat from the refrigeration cycle to be actively utilized to heat the high-temperature side liquid, and by minimizing the amount of heater usage when heating the high-temperature side liquid, the running costs of the two-system liquid temperature control device can be reduced.

[0008] Furthermore, it is preferable that the system further includes a heater arranged downstream of the bypass path in the high-temperature side liquid circulation path and upstream of the first temperature measuring device, and a second temperature measuring device arranged downstream of the evaporator in the low-temperature side liquid circulation path to measure the temperature of the low-temperature side liquid, and when the first measurement value is less than the high-temperature side set temperature and the second measurement value measured by the second temperature measuring device has reached a predetermined low-temperature side set temperature, the operation control unit executes a process of heating the high-temperature side liquid with the heater until the first measurement value reaches the high-temperature side set temperature.

[0009] As a result, when the amount of heat released from the first condenser decreases due to the cooling of the low-temperature side liquid reaching the target temperature, the high-temperature side liquid can be heated using the heater. Therefore, even if the difference between a reference temperature such as room temperature and the set temperature of the high-temperature side liquid (high-temperature side set temperature) is larger than the difference between the reference temperature and the set temperature of the low-temperature side liquid (low-temperature side set temperature), the high-temperature side liquid can be reliably raised to the high-temperature side set temperature.

[0010] It is also preferable that the system further includes a cooler through which cooling water circulates to exchange heat with the high-temperature side liquid, and when the first measurement value is equal to or higher than the high-temperature side set temperature, the operation control unit executes a process of circulating the cooling water to the cooler so that the first measurement value maintains the high-temperature side set temperature.

[0011] This allows the temperature of the high-temperature side liquid to be appropriately managed after the high-temperature side liquid has reached the high-temperature side set temperature. [Effects of the Invention]

[0012] According to the configuration of the present invention, the high-temperature side liquid can be heated by actively utilizing the exhaust heat in the refrigeration cycle, and by minimizing the amount of heater usage when heating the high-temperature side liquid, running costs can be reduced. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is an overall configuration diagram of a two-system liquid temperature adjustment device according to the present embodiment. [Figure 2] 10 is a graph showing changes over time in the measured high-temperature side refrigerant temperature value and the measured low-temperature side refrigerant temperature value in a first temperature setting state. [Figure 3] 10 is a graph showing changes over time in the measured high-temperature side refrigerant temperature value and the measured low-temperature side refrigerant temperature value in the second temperature setting state. DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment of a dual-system liquid temperature control device 100 according to the present invention will now be described with reference to the drawings. As shown in FIG. 1, the dual-system liquid temperature control device 100 in this embodiment includes a refrigeration cycle 10, a high-temperature side temperature adjustment unit 22 for the device to be cooled 20, a high-temperature side refrigerant circulation path (high-temperature side liquid circulation path) 30, a low-temperature side temperature adjustment unit 24 for the device to be cooled 20, a low-temperature side refrigerant circulation path (low-temperature side liquid circulation path) 40, a cooler 50, a cooling water supply unit 60, and an operation control unit 70. Here, a configuration in which a high-temperature side refrigerant is used as the high-temperature side liquid and a low-temperature side refrigerant is used as the low-temperature side liquid will be described. Note that the term "two systems" in the dual-system liquid temperature control device 100 does not refer to the number of paths through which the liquid flows, but rather refers to two systems of liquid temperature. Note that the dashed lines in the figure indicate communication paths between each component and the operation control unit 70, but the specific form of the communication paths is not particularly limited, and may be wireless or wired.

[0015] The refrigeration cycle 10 includes a compressor 11, a first condenser 12, a second condenser 13, an expansion valve 14, and an evaporator 15, and circulates a refrigerant while changing its state. In the present embodiment, a temperature and pressure measuring instrument 16 is disposed between the second condenser 13 and the expansion valve 14 in the refrigeration cycle 10. A portion of the high-temperature refrigerant circulation path 30 is disposed in the first condenser 12 for heat exchange. The first condenser 12 exchanges heat between the refrigeration cycle refrigerant and the high-temperature refrigerant circulating through the high-temperature refrigerant circulation path 30, thereby heating the high-temperature refrigerant. The second condenser 13 is also disposed with a second supply path 62, which is a portion of the cooling water supply unit 60, for heat exchange. A second flow rate control valve 64 is disposed in the second supply path 62, allowing adjustment of the amount of heat radiation in the second condenser 13. In the second condenser 13, heat exchange occurs between the refrigeration cycle refrigerant and the cooling water supplied from the second supply path 62.

[0016] A portion of the low-temperature side refrigerant circulation path 40 passes through the evaporator 15, and heat exchange occurs between the evaporator 15 and the low-temperature side refrigerant circulating therethrough, cooling the low-temperature side refrigerant. The temperature and pressure gauge 16 measures at least one of the temperature and pressure of the refrigeration cycle refrigerant circulating in the refrigeration cycle 10. The refrigeration cycle refrigerant measurement values ​​measured by the temperature and pressure gauge 16 are transmitted to the operation control unit 70. In the present embodiment, the refrigeration cycle 10 is provided with the temperature and pressure gauge 16 between the second condenser 13 and the expansion valve 14, but this is not limiting. Alternatively, a refrigeration cycle refrigerant temperature gauge and a refrigeration cycle refrigerant pressure gauge (neither of which are shown) may be provided instead of the temperature and pressure gauge 16. At least one of the refrigeration cycle refrigerant temperature measured by the refrigeration cycle refrigerant temperature gauge and the refrigeration cycle refrigerant pressure measured by the refrigeration cycle refrigerant pressure gauge is used as the refrigeration cycle refrigeration cycle refrigeration cycle refrigerant measurement value.

[0017] The apparatus to be cooled 20 has a high-temperature-side temperature adjustment unit 22 that operates at high temperatures (e.g., 30°C to 120°C) and a low-temperature-side temperature adjustment unit 24 that operates at low temperatures (e.g., -20°C to 10°C). The high-temperature-side temperature adjustment unit 22 is cooled by a high-temperature-side refrigerant that serves as a high-temperature-side liquid and is circulated through a high-temperature-side refrigerant circulation path 30 and adjusted to a temperature of approximately 90°C. The low-temperature-side temperature adjustment unit 24 is cooled by a low-temperature-side refrigerant that serves as a low-temperature-side liquid and is circulated through a low-temperature-side refrigerant circulation path 40 and adjusted to a temperature of approximately -20°C. An example of such an apparatus to be cooled 20 is a semiconductor manufacturing apparatus, but the apparatus to be cooled 20 is not limited to semiconductor manufacturing apparatus. Furthermore, the operating temperatures of the high-temperature-side temperature adjustment unit 22 and the low-temperature-side temperature adjustment unit 24 are not limited to the temperature ranges exemplified in this embodiment.

[0018] The high-temperature side refrigerant circulation path 30 circulates the high-temperature side refrigerant between the first condenser 12 of the refrigeration cycle 10 and the high-temperature side temperature adjustment unit 22 of the device to be cooled 20. The high-temperature side refrigerant circulation path 30 is provided with a heater 31, a high-temperature side refrigerant temperature measurement device 32 as a first temperature measurement device, and a cooler 50. The high-temperature side refrigerant is temperature-adjusted to a high-temperature side set temperature by the first condenser 12, the heater 31, and the cooler 50, and then supplied to the high-temperature side temperature adjustment unit 22 of the device to be cooled 20, where it cools the high-temperature side temperature adjustment unit 22 so that the high-temperature side temperature adjustment unit 22 maintains a predetermined operating temperature. The high-temperature side refrigerant circulation path 30 is also provided with a bypass path 33 for avoiding heat exchange of the high-temperature side refrigerant in the first condenser 12. A diverter valve 34 is provided at an upstream branch of the bypass path 33 for adjusting the flow rate of the high-temperature side refrigerant undergoing heat exchange in the first condenser 12. High-temperature-side refrigerant temperature measuring device 32 measures the temperature of the high-temperature-side refrigerant circulating through high-temperature-side refrigerant circulation path 30, and the measured high-temperature-side refrigerant measured temperature as a first measured value is automatically sent to operation control unit 70. Operation control unit 70 controls the operations of heater 31, flow dividing valve 34, and cooler 50 based on the high-temperature-side refrigerant measured temperature.

[0019] The low-temperature side refrigerant circulation path 40 circulates the low-temperature side refrigerant between the evaporator 15 of the refrigeration cycle 10 and the low-temperature side temperature adjustment unit 24 of the device to be cooled 20. A low-temperature side refrigerant temperature measuring device 42 serving as a second temperature measuring device is disposed in the low-temperature side refrigerant circulation path 40 downstream of the evaporator 15. The low-temperature side refrigerant temperature measuring device 42 measures the temperature of the low-temperature side refrigerant circulating through the low-temperature side refrigerant circulation path 40, and the measured low-temperature side refrigerant measured temperature serving as a second measured value is automatically transmitted to the operation control unit 70. After the temperature of the low-temperature side refrigerant is adjusted to the low-temperature side set temperature, it is supplied to the low-temperature side temperature adjustment unit 24 of the device to be cooled 20 and cools the low-temperature side temperature adjustment unit 24 so that the low-temperature side temperature adjustment unit 24 maintains a predetermined operating temperature.

[0020] The cooler 50 cools the high-temperature-side refrigerant that has returned from the high-temperature-side temperature adjustment unit 22 of the device to be cooled 20. In this embodiment, the cooler 50 is disposed upstream of the position of the flow dividing valve 34, which is the upstream connecting part of the bypass path 33. The cooling performance of the cooler 50 is adjusted by the flow rate and temperature of the cooling water supplied from the cooling water supply unit 60, whose operation is controlled by the operation control unit 70, and the function of the cooler 50 can also be switched on and off.

[0021] The cooling water supply unit 60 has a first supply path 61 that supplies cooling water to the cooler 50 and a second supply path 62 that supplies cooling water to the second condenser 13 of the refrigeration cycle 10. A first flow rate adjustment valve 63 is disposed in the first supply path 61, and a second flow rate adjustment valve 64 is disposed in the second supply path 62. The first supply path 61 after passing through the cooler 50 and the second supply path 62 after passing through the second condenser 13 are connected to a return path 65. The operation of the first flow rate adjustment valve 63 is controlled by an operation control unit 70 based on the high-temperature-side refrigerant measured temperature measured by the high-temperature-side refrigerant temperature measuring instrument 32. The operation of the second flow rate adjustment valve 64 is controlled by the operation control unit 70 based on at least one of the refrigeration cycle refrigerant measured temperature and the refrigeration cycle refrigerant measured pressure measured by the temperature and pressure measuring instrument 16.

[0022] The dual-system liquid temperature adjustment device 100 of this embodiment has the above-described configuration. Next, a method for using the dual-system liquid temperature adjustment device 100 of this embodiment will be specifically described.

[0023] (First set temperature state) As shown in FIG. 2, the first set temperature state is a set temperature state in which the difference ΔT1 (20°C) between the reference temperature (here, room temperature, 20°C) and the high-side set temperature (40°C) is smaller than the difference ΔT2 (40°C) between the reference temperature and the low-side set temperature (-20°C). For ease of explanation, only the temperature difference is focused on here. However, the temperature difference may not be the only factor, as factors such as the flow rates and types (physical properties, etc.) of the high-side and low-side refrigerants, and the heat capacities of the high-side temperature adjustment unit 22 and the low-side temperature adjustment unit 24 also affect the first set temperature state. In this first set temperature state, if the dual-system liquid temperature adjustment device 100 simultaneously heats the high-side refrigerant and cools the low-side refrigerant, the high-side refrigerant will reach the high-side set temperature before the low-side refrigerant reaches the low-side set temperature. Furthermore, since the exhaust heat temperature (here, 80°C) in the first condenser 12 is higher than the high-temperature set temperature, the high-temperature side refrigerant can be heated only by the exhaust heat from the first condenser 12 when cooling the low-temperature side refrigerant. Therefore, the high-temperature side refrigerant can be heated to the high-temperature side set temperature without using the heater 31.

[0024] When an operator starts the dual-system liquid temperature control device 100 in the cold state, the compressor 11 compresses the refrigeration cycle refrigerant and sends it to the first condenser 12, starting the refrigeration cycle 10. Then, before, after, or simultaneously with the start of the refrigeration cycle 10, the high-temperature refrigerant begins circulating through the high-temperature refrigerant circuit 30 and the low-temperature refrigerant begins circulating through the low-temperature refrigerant circuit 40. The high-temperature refrigerant temperature gauge 32 measures the temperature of the high-temperature refrigerant, and the low-temperature refrigerant temperature gauge 42 measures the temperature of the low-temperature refrigerant. The temperature and pressure gauge 16 measures at least one of the temperature and pressure of the refrigeration cycle refrigerant. The measured values ​​of the high-temperature refrigerant temperature gauge 32, the low-temperature refrigerant temperature gauge 42, and the temperature and pressure gauge 16 are automatically sent to the operation control unit 70.

[0025] Because the measured high-temperature side refrigerant temperature at this time is lower than the preset high-temperature side temperature, the operation control unit 70 stops the functions of the second condenser 13, the heater 31, and the cooler 50 (i.e., the second condenser 13 does not radiate heat, the heater 31 does not heat, and the cooler 50 does not cool). The operation control unit 70 also controls the operation of the diverter valve 34 to supply a volume of the total amount of high-temperature side refrigerant to the first condenser 12, the volume corresponding to a first capacity (0≦first capacity≦total amount) stored in a memory unit (not shown) that is part of the configuration of the operation control unit 70. This allows the high-temperature side refrigerant to be heated using the exhaust heat from the first condenser 12. The first capacity is set in advance by a user or the like and stored in the memory unit. In this embodiment, the first capacity is the total amount of high-temperature side refrigerant; however, the first capacity can be any capacity greater than or equal to 0 and less than the total amount of high-temperature side refrigerant.

[0026] The measured high-temperature side refrigerant temperature immediately after starting up from a cold state is significantly lower than the high-temperature set temperature to be maintained in the high-temperature side temperature adjustment unit 22 of the device 20 to be cooled. For this reason, there are cases where it is desired to heat the high-temperature side refrigerant as quickly as possible. In such cases, the operator can input an option command to rapidly heat the high-temperature side refrigerant using a known input means (not shown), which causes the operation control unit 70 to operate the heater 31, thereby additionally heating the high-temperature side refrigerant that has exchanged heat with the first condenser 12 (and the high-temperature side refrigerant diverted to the bypass path 33 by the diverter valve 34).

[0027] In this embodiment, the high-temperature side set temperature is sufficiently lower than the exhaust heat temperature of the first condenser 12. However, there are cases where the difference between the high-temperature side set temperature and the exhaust heat temperature of the first condenser 12 is small. That is, when the high-temperature side refrigerant that has approached the high-temperature side set temperature circulates through the high-temperature side refrigerant circulation path 30, the high-temperature side refrigerant may not be able to sufficiently absorb the exhaust heat of the first condenser 12, which may reduce the function of the first condenser 12 as a condenser and result in insufficient cooling of the low-temperature side refrigerant. In such cases, the operation control unit 70 may execute a process to supplement the cooling of the low-temperature side refrigerant by starting the supply of cooling water to the second condenser 13.

[0028] As described above, when the dual-system liquid temperature control device 100 is operated for a certain period while preventing insufficient cooling of the low-temperature side refrigerant by the refrigeration cycle 10, the measured high-temperature side refrigerant temperature reaches or exceeds the high-temperature side set temperature before the low-temperature side refrigerant is cooled to the low-temperature side set temperature. When the measured high-temperature side refrigerant temperature reaches or exceeds the high-temperature side set temperature, the operation control unit 70 operates the diverter valve 34 to supply a preset second capacity (0≦second capacity≦total capacity) of the total capacity of the high-temperature side refrigerant to the bypass path 33. The operation control unit 70 also stops the function of the first condenser 12 and executes a process to supply cooling water to the second condenser 13 and the cooler 50, and, if the heater 31 has been used, executes a process to stop the heater 31. Note that, in this embodiment, the second capacity is the total capacity of the high-temperature side refrigerant, but the second capacity can be any capacity greater than or equal to 0 and less than the total capacity of the high-temperature side refrigerant.

[0029] The cooler 50 adjusts the temperature of the high-temperature side refrigerant (cooling process) by adjusting the cooling water supplied from the first supply path 61 so that the temperature of the high-temperature side refrigerant returned from the high-temperature side temperature adjustment unit 22 of the device to be cooled 20 is maintained at the high-temperature side set temperature. In addition, the operation control unit 70 controls the flow rate and temperature of the cooling water supplied to the cooler 50 using the first flow rate adjustment valve 63 so that the measured high-temperature side refrigerant temperature is maintained at the high-temperature side set temperature. Furthermore, the operation control unit 70 compares the measured value of the refrigeration cycle refrigerant temperature from the temperature and pressure measuring device 16 with a preset refrigeration cycle refrigerant set temperature (refrigeration cycle refrigerant setting condition). Based on the comparison result, the operation control unit 70 determines whether the heat exchange by the second condenser 13 (the cooling of the low-temperature side refrigerant by the refrigeration cycle 10) is appropriate, and can also perform a process to optimize the heat exchange by the second condenser 13.

[0030] As described above, the refrigeration cycle 10 using the second condenser 13 instead of the first condenser 12 can maintain the cooling performance of the low-temperature side refrigerant. Specifically, the operation control unit 70 maintains the cooling performance of the low-temperature side refrigerant in the refrigeration cycle 10 by starting the supply of cooling water from the second supply path 62 to the second condenser 13, increasing or decreasing the amount of cooling water supplied relative to the normal supply amount, or heating or cooling the cooling water relative to the normal supply temperature, based on the measured refrigeration cycle refrigerant temperature and the set refrigeration cycle refrigerant temperature. When the measured low-temperature side refrigerant temperature reaches the set low-temperature side temperature, the operation control unit 70 adjusts the capacity of the refrigeration cycle 10 so that the measured low-temperature side refrigerant temperature maintains the set low-temperature side temperature. Of course, the operation control unit 70 continues the process of maintaining the high-temperature side refrigerant at the set high-temperature side temperature after the measured high-temperature side refrigerant temperature reaches the set high-temperature side temperature.

[0031] As described above, the dual-system liquid temperature control device 100 can minimize the use of the heater 31 when circulating the high-temperature refrigerant between the device to be cooled 20 and the refrigeration cycle 10 while maintaining the high-temperature set temperature and the low-temperature refrigerant at the low-temperature set temperature. This is advantageous in that it reduces the running costs of the dual-system liquid temperature control device 100. Then, when the measured high-temperature refrigerant temperature reaches the high-temperature set temperature and the measured low-temperature refrigerant temperature reaches the low-temperature set temperature, an operator places a workpiece (not shown) in the device to be cooled 20, which then starts operating and performs a predetermined process on the workpiece. When the device to be cooled 20 begins processing the workpiece, the high-temperature refrigerant and the low-temperature refrigerant absorb heat from the workpiece, and the measured high-temperature refrigerant temperature becomes higher than the high-temperature set temperature and the measured low-temperature refrigerant temperature becomes higher than the low-temperature set temperature. Therefore, the operation control unit 70 continues the cooling process by the cooler 50 so that the high-temperature side refrigerant temperature measurement value maintains the high-temperature side set temperature, and continues to adjust the cooling capacity of the refrigeration cycle 10 so that the low-temperature side refrigerant temperature measurement value maintains the low-temperature side set temperature.

[0032] (Second set temperature state) As shown in FIG. 3, the second set temperature state is a set temperature state in which the difference ΔT1 between the reference temperature (room temperature) and the high-side set temperature is greater than the difference ΔT2 between the reference temperature and the low-side set temperature. For ease of explanation, as with the first set temperature state, only the temperature difference is focused on here. However, the temperature difference may not be the only factor, as factors such as the flow rates and types (physical properties, etc.) of the high-side and low-side refrigerants, and the thermal capacities of the high-side temperature adjustment unit 22 and the low-side temperature adjustment unit 24 also affect the second set temperature state. In the second set temperature state, when the dual-system liquid temperature control device 100 simultaneously heats the high-side refrigerant and cools the low-side refrigerant from room temperature, the measured low-side refrigerant temperature reaches the low-side set temperature before the measured high-side refrigerant temperature reaches the high-side set temperature. In other words, even if the high-side refrigerant is heated using the exhaust heat from the first condenser 12, the exhaust heat from the first condenser 12 is reduced, making it impossible to heat the high-side refrigerant to the high-side set temperature using only the exhaust heat from the first condenser 12.

[0033] Therefore, in the temperature range that cannot be heated using the exhaust heat of the first condenser 12 (the range of 60°C to 80°C in FIG. 3), the operation control unit 70 executes a process to heat the high-temperature side refrigerant to the high-temperature side set temperature using the heater 31. Note that the operation of the dual-system liquid temperature control device 100 until the low-temperature side refrigerant reaches the low-temperature side set temperature in the second set temperature state is the same as the basic operation in the first set temperature state (operation except for the operation when the high-temperature side refrigerant temperature measurement value approaches the high-temperature side set temperature), and therefore will not be described here. Below, we will explain the operation of the dual-system liquid temperature control device 100 after the low-temperature side refrigerant has reached the low-temperature side set temperature.

[0034] In the second set temperature state, when the low temperature side refrigerant measurement value reaches the low temperature side set temperature, the operation control unit 70 executes a process to maintain the low temperature side refrigerant temperature measurement value of the low temperature side refrigerant at the low temperature side set temperature. Specifically, the operation control unit 70 executes a process to adjust the cooling capacity of the refrigeration cycle 10 (to reduce the cooling capacity). Such a process to adjust the cooling capacity of the refrigeration cycle 10 reduces the exhaust heat from the first condenser 12, making it impossible to heat the high temperature side refrigerant to the high temperature side set temperature using only the exhaust heat from the first condenser 12.

[0035] Therefore, when the measured high-temperature side refrigerant temperature is less than the high-temperature side set temperature and the measured low-temperature side refrigerant temperature has reached the low-temperature side set temperature, the operation control unit 70 performs heat exchange in the first condenser 12 and heats the high-temperature side refrigerant with the heater 31. At this time, the second condenser 13 and the cooler 50 continue to be in a stopped state. The operation control unit 70 can also control the operation of the diverter valve 34 to circulate a first volume of the entire amount of high-temperature side refrigerant through the bypass path 33. Of course, the operation control unit 70 continues to maintain the low-temperature side refrigerant at the low-temperature side set temperature after the measured low-temperature side refrigerant temperature has reached the low-temperature side set temperature.

[0036] As described above, when the high-temperature-side refrigerant is heated by the first condenser 12 and the heater 31 and the high-temperature-side refrigerant reaches or exceeds the high-temperature-side set temperature, the operation control unit 70 executes a process to stop the functions of the first condenser 12 and the heater 31 and a process to supply cooling water to the second condenser 13 and the cooler 50. When the low-temperature-side refrigerant temperature measurement value reaches the low-temperature-side set temperature and the high-temperature-side refrigerant temperature measurement value reaches the high-temperature-side set temperature, an operator places a workpiece (not shown) on the apparatus to be cooled 20, which then starts operating and performs a predetermined process on the workpiece. When the apparatus to be cooled 20 begins processing the workpiece, the high-temperature-side refrigerant temperature measurement value and the low-temperature-side refrigerant absorb heat from the workpiece, and the high-temperature-side refrigerant temperature measurement value reaches or exceeds the high-temperature-side set temperature and exceeds the low-temperature-side set temperature. At this time, the operation control unit 70 continues the cooling process by the cooler 50 so that the high-temperature-side refrigerant temperature measurement value maintains the high-temperature-side set temperature, and also executes a process to adjust the cooling capacity of the refrigeration cycle 10 so that the low-temperature-side refrigerant temperature measurement value maintains the low-temperature-side set temperature.

[0037] As described above, when the high-temperature side refrigerant is set to the high-temperature side set temperature and the low-temperature side refrigerant is set to the low-temperature side set temperature using the dual-system liquid temperature adjustment device 100, the exhaust heat of the first condenser 12 is utilized as much as possible, thereby reducing the use of the heater 31. This is advantageous in that the running costs of the dual-system liquid temperature adjustment device 100 can be reduced.

[0038] The second set temperature state is exemplified as a set temperature state in which the difference ΔT1 between the reference temperature (room temperature) and the high-side set temperature is larger than the difference ΔT2 between the reference temperature and the low-side set temperature, but is not limited to this. Even if the difference ΔT1 between the reference temperature (room temperature) and the high-side set temperature is smaller than the difference ΔT2 between the reference temperature and the low-side set temperature, the same processing as the second set temperature state can be selected if the high-side set temperature is higher than the exhaust heat temperature of the first condenser 12.

[0039] Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments. For example, in the above embodiments, the cooler 50 is disposed upstream of the flow dividing valve 34, which is the upstream connecting part of the bypass path 33, but the present invention is not limited to this configuration. The cooler 50 can be disposed at any position within the high-temperature refrigerant circulation path 30.

[0040] When the cooler 50 is disposed upstream of the diverter valve 34, which is the upstream connecting portion of the bypass path 33, an additional high-temperature-side refrigerant temperature measuring device (not shown) may be disposed between the cooler 50 and the diverter valve 34. The operation control unit 70 then executes a process to calculate the difference between the high-temperature-side refrigerant temperature measured by the additional high-temperature-side refrigerant temperature measuring device after the cooling process by the cooler 50 and the high-temperature-side set temperature. If the calculated difference exceeds a preset threshold (i.e., the cooler 50 is supercooled), the operation control unit 70 can also execute a process to control the operation of the diverter valve 34 and heat a portion of the high-temperature-side refrigerant after the cooling process with exhaust heat from the first condenser 12. By executing this process, the high-temperature-side refrigerant after the cooling process is supplied to the device to be cooled 20 while maintaining the high-temperature-side set temperature with high accuracy.

[0041] Furthermore, in the first set temperature state, even if the difference ΔT1 between the reference temperature (room temperature) and the high-temperature set temperature is smaller than the difference ΔT2 between the reference temperature (room temperature) and the low-temperature set temperature, it is also possible that the exhaust heat temperature of the first condenser 12 is lower than the high-temperature set temperature. In such a case, the operation control unit 70 executes a process of heating the high-temperature side refrigerant using only the exhaust heat of the first condenser 12 until the measured high-temperature side refrigerant temperature value reaches the exhaust heat temperature of the first condenser 12. Then, the operation control unit 70 executes a process of heating the high-temperature side refrigerant with the heater 31 until the measured high-temperature side refrigerant temperature value reaches from the exhaust heat temperature of the first condenser 12 to the high-temperature side set temperature.

[0042] It is also possible to adopt a form in which the modified examples described in the above embodiments are combined as appropriate. [Explanation of symbols]

[0043] 10: Refrigeration cycle 11: Compressor, 12: First condenser, 13: Second condenser, 14: Expansion valve, 15: Evaporator, 16: Temperature and pressure measuring instrument (temperature and pressure measuring instrument for refrigeration cycle) 20: Cooling target device 22: High temperature side temperature adjustment section, 24: Low temperature side temperature adjustment section 30: High temperature side refrigerant circulation path 31: heater, 32: high temperature side refrigerant temperature measuring instrument (first temperature measuring instrument), 33: Bypass route, 34: Diversion valve 40: Low temperature side refrigerant circulation path 42: Temperature measuring instrument for low-temperature side refrigerant (second temperature measuring instrument) 50:Cooler 60: Cooling water supply section 61: First supply path, 62: Second supply path, 63: First flow rate adjustment valve, 64: Second flow rate adjustment valve, 65: Return flow path 70: Motion control unit 100:2 system liquid temperature controller

Claims

1. a refrigeration cycle having a compressor, a first condenser, a second condenser, an expansion valve, and an evaporator, and circulating a refrigerant for the refrigeration cycle; a high-temperature-side liquid circulation path that circulates high-temperature-side liquid between at least the first condenser and the high-temperature-side temperature adjustment unit; a low-temperature side liquid circulation path that circulates low-temperature side liquid at least between the evaporator and the low-temperature side temperature adjustment unit; a first temperature measuring device disposed downstream of the first condenser in the high-temperature side liquid circulation path and configured to measure a temperature of the high-temperature side liquid; a bypass path that is provided in the high-temperature side liquid circulation path, that connects the upstream side of the first condenser with a position that is downstream of the first condenser and upstream of the first temperature measuring device, and that bypasses the first condenser; a dividing valve disposed at an upstream connection portion of the high-temperature side liquid circulation path with respect to the bypass path, dividing the high-temperature side liquid into the high-temperature side liquid circulation path and the bypass path; an operation control unit that controls the operation of at least the flow dividing valve; The operation control unit A two-system liquid temperature control device characterized in that, when a first measurement value measured by the first temperature measuring device is lower than a predetermined high-temperature side set temperature, the diverter valve is controlled to perform a process of heat exchanging a predetermined first volume of the total volume of the high-temperature side liquid in the first condenser, and when the first measurement value becomes equal to or higher than the high-temperature side set temperature, the diverter valve is controlled so that the first measurement value maintains the high-temperature side set temperature, and a process of diverting a predetermined second volume of the total volume of the high-temperature side liquid to the bypass path is performed.

2. a heater disposed in the high-temperature-side liquid circulation path downstream of the bypass path and upstream of the first temperature measuring device; a second temperature measuring device disposed downstream of the evaporator in the low-temperature side liquid circulation path and configured to measure the temperature of the low-temperature side liquid; When the first measurement value is less than the high temperature setting temperature and the second measurement value measured by the second temperature measuring device reaches a preset low temperature setting temperature, The operation control unit 2. The two-system liquid temperature control device according to claim 1, wherein the heater heats the high-temperature side liquid until the first measurement value reaches the high-temperature side set temperature.

3. a cooler through which cooling water circulates to exchange heat with the high-temperature liquid; When the first measurement value is equal to or higher than the high temperature setting temperature, The operation control unit 3. The dual-system liquid temperature control device according to claim 1, wherein a process is executed to circulate the cooling water through the cooler so that the first measurement value maintains the higher temperature set temperature.

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