EP4692673A1

EP4692673A1 - Temperature regulating device

Info

Publication number: EP4692673A1
Application number: EP24779724.4A
Authority: EP
Inventors: Keigo Suzuki
Original assignee: SMC Corp
Current assignee: SMC Corp
Priority date: 2023-03-31
Filing date: 2024-03-19
Publication date: 2026-02-11
Also published as: TW202445071A; WO2024203599A1; JP2024145807A; CN120981689A; KR20250166217A

Abstract

[Object] To provide a temperature regulating device that is capable of accurately grasping a change in the amount of a circulating liquid flowing between the temperature regulating device and a load and that is capable of early detecting leakage of the circulating liquid.

[Solution] A temperature regulating device 1 includes: a main tank 20 storing a circulating liquid L; a circulation passage 10, through which the circulating liquid in the tank is sent to a load 70 and which receives the circulating liquid from the load to send the circulating liquid to the tank; a circulating pump 23 configured to send the circulating liquid in the tank to the load through the circulation passage; a temperature control unit 8, which is provided to the circulation passage and which is configured to control a temperature of the circulating liquid that has regulated a temperature of the load; and a control unit 60 including a processor 61 configured to execute a leakage detection process of detecting leakage of the circulating liquid. The tank includes a level switch 55 configured to detect a level of the circulating liquid, and a liquid level reference position Ps, where the detection of the leakage of the circulating liquid starts, the liquid level reference position Ps being located above the switch. When the level of the circulating liquid is detected by the switch within a first set time in the leakage detection process, the processor determines that the circulating liquid is leaked from the temperature regulating device and outputs a first alarm signal.

Description

Technical Field

The present invention relates to a temperature regulating device configured to control the temperature of a load so as to be a desired temperature by supplying, to the load, a circulating liquid whose temperature is regulated.

Background Art

A temperature regulating device configured to regulate the temperature of a load so as to be a desired temperature by supplying, to the load, a circulating liquid whose temperature is regulated has been widely known as disclosed in, for example, PTL 1. In the existing temperature regulating device, the circulating liquid for regulating the temperature of the load is supplied from a main tank to the load through a feed passage and regulates the temperature of the load. Then, the circulating liquid that has regulated the temperature of the load flows back to a return passage, is controlled so as to have a certain temperature by, for example, a heat exchanger or a heater, and is stored in the main tank again. In addition, the main tank is provided with level sensors such as level switches configured to detect the level of the circulating liquid. The circulating liquid can be supplied from a sub tank to the main tank or an alarm can be given by detecting the level of the circulating liquid with the level sensor.
Meanwhile, in the case of a temperature regulating device in which, for example, a fluorinated liquid is used as such a circulating liquid, the amount of the circulating liquid to be used has to be appropriately managed in consideration of the environmental effects. In particular, if the circulating liquid is leaked to the outside, there is also a possibility of adverse effects on the temperature regulating function of the temperature regulating device.
However, the existing temperature regulating device is incapable of accurately grasping a change in the amount of the circulating liquid flowing between the temperature regulating device and the load. Thus, it is difficult to early detect leakage of the circulating liquid.

Citation List

Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No. 2005-106434

Summary of Invention

Technical Problem

Accordingly, a technical object of the present invention is to provide a temperature regulating device that is capable of accurately grasping a change in the amount of a circulating liquid flowing between the temperature regulating device and a load and that is capable of early detecting leakage of the circulating liquid.

Solution to Problem

To achieve the technical object, the temperature regulating device according to the present invention is a temperature regulating device for regulating a temperature of a load so as to be a predetermined set temperature, the temperature regulating device including: a main tank storing a circulating liquid for regulating the temperature of the load; a circulation passage through which the circulating liquid in the main tank is sent to the load and that receives the circulating liquid that has regulated the temperature of the load to send the circulating liquid to the main tank; a circulating pump configured to send the circulating liquid in the main tank to the load through the circulation passage; a temperature control unit that is provided to the circulation passage and that is configured to control a temperature of the circulating liquid that has regulated the temperature of the load; and a control unit including a processor configured to execute a leakage detection process of detecting leakage of the circulating liquid. The main tank includes a first level detection sensor configured to detect a level of the circulating liquid stored in the main tank, and a liquid level reference position where the leakage detection process starts, the liquid level reference position being located at a position above the first level detection sensor, and when the level in the main tank is detected by the first level detection sensor within a preset first set time in the leakage detection process, the processor determines that the circulating liquid is leaked from the temperature regulating device and outputs a first alarm signal.
In this case, preferably, the temperature control unit includes a heat exchanger configured to exchange heat with the circulating liquid, and a heat exchange circuit configured to supply, to the heat exchanger, a heat exchange medium to be subjected to heat exchange with the circulating liquid. In addition, preferably, the temperature regulating device further includes: a sub tank in which the main tank is disposed and that stores the circulating liquid; and a supply pump configured to supply the circulating liquid in the sub tank into the main tank. The liquid level reference position is defined by a communication hole that passes through a side wall of the main tank and that allows an inside of the main tank and an inside of the sub tank to communicate with each other, or an upper edge of the side wall of the main tank.
In addition, preferably, when the level in the main tank is not detected by the first level detection sensor within the first set time in the leakage detection process, the processor causes the level of the circulating liquid in the main tank to reach the liquid level reference position by driving the supply pump for a preset second set time and by supplying the circulating liquid in the sub tank to the main tank and restarts the leakage detection process.
In addition, preferably, the circulation passage includes a feed passage for sending the circulating liquid in the main tank to the load, the feed passage being connected to the main tank, and a return passage that receives the circulating liquid that has regulated the temperature of the load to return the circulating liquid to the main tank, the feed passage of the circulation passage is provided with a temperature sensor configured to detect a temperature of the circulating liquid sent from the main tank, and when the temperature regulating device starts operation, the processor executes a circulating liquid temperature monitoring process of monitoring whether the temperature of the circulating liquid detected by the temperature sensor satisfies a predetermined condition, and when the temperature of the circulating liquid satisfies the predetermined condition in the circulating liquid temperature monitoring process, the processor causes the level of the circulating liquid in the main tank to reach the liquid level reference position by driving the supply pump for a preset second set time and by supplying the circulating liquid in the sub tank to the main tank and starts the leakage detection process. In addition, preferably, the predetermined condition is that a state in which the temperature of the circulating liquid detected by the temperature sensor is maintained at the set temperature continues for a preset third predetermined time.
In addition, preferably, when the temperature of the circulating liquid detected by the temperature sensor does not satisfy the set temperature during execution of the leakage detection process, the processor stops the leakage detection process and executes the circulating liquid temperature monitoring process.
In addition, preferably, the sub tank is provided with an upper limit level sensor configured to detect an upper limit position where a level of the circulating liquid stored in the sub tank does not reach a bottom of the main tank, and when the upper limit position is detected by the upper limit level sensor, the processor determines that there is a possibility of contact of the circulating liquid in the sub tank with the main tank and outputs a second alarm signal.

Advantageous Effects of Invention

A temperature regulating device that is capable of accurately grasping a change in the amount of a circulating liquid flowing between the temperature regulating device and a load and that is capable of early detecting leakage of the circulating liquid can be provided as the temperature regulating device according to the present invention.

Brief Description of Drawings

[Fig. 1] Fig. 1 is a circuit diagram of a temperature regulating device according to an embodiment of the present invention illustrating a state in which the liquid of a circulating liquid in a main tank is located at a liquid level reference position.
[Fig. 2] Fig. 2 is an enlarged view of an upper part of the main tank.
[Fig. 3] Fig. 3 illustrates a state in which the main tank is full of the circulating liquid supplied from the inside of a sub tank.
[Fig. 4] Fig. 4 illustrates a state in which the level of the circulating liquid in the main tank is lowered and detected by a level detection sensor.
[Fig. 5] Fig. 5 is a flowchart of a processor for detecting leakage of the circulating liquid from a passage during operation of the temperature regulating device.

Description of Embodiments

Figs. 1 to 5 illustrate an embodiment of a temperature regulating device according to the present invention. In the description of the present embodiment, for example, a load is a semiconductor manufacturing apparatus, and a circulating liquid that cools the load is an insulating refrigerant (for example, a fluorinated liquid).
As illustrated in Figs. 1 and 2, a temperature regulating device 1 is formed by including a housing 3, which covers the exterior of the temperature regulating device 1, a main tank 20, which stores a circulating liquid L for regulating the temperature of a load 70, a circulation passage 10, through which the circulating liquid L in the main tank 20 is sent to the load 70 and which receives the circulating liquid L that has regulated the temperature of the load 70 to send the circulating liquid L to the main tank 20, a circulating pump 23, which is configured to send the circulating liquid L in the main tank 20 to the load 70 through the circulation passage 10, a temperature control unit 8, which is provided to the circulation passage 10 and which is configured to control the temperature of the circulating liquid L that has regulated the temperature of the load 70, a sub tank 40, in which the main tank 20 is disposed and which stores the circulating liquid L, a supply pump 51, which is configured to supply the circulating liquid L in the sub tank 40 into the main tank 20, and a control unit 60, which includes a processor 61 configured to execute a leakage detection process of detecting leakage of the circulating liquid L. In the present embodiment, the temperature control unit 8 includes a heat exchanger 11, which is configured to exchange heat with the circulating liquid L, a refrigeration circuit 30 (heat exchange circuit), which is configured to supply, to the heat exchanger 11, a refrigerant (heat exchange medium) to be subjected to heat exchange with the circulating liquid L, and a heater 24, which is configured to heat the circulating liquid L in the main tank 20.
Then, the circulation passage 10, the main tank 20, the circulating pump 23, the temperature control unit 8, the sub tank 40, the supply pump 51, and the control unit 60 are housed in the one housing 3. Then, a circulating liquid discharge port 16a and a circulating liquid return port 14a of the circulation passage 10, and a heat dissipating water supply port 25a and a heat dissipating water discharge port 25b for heat dissipating water to be supplied to a condenser 32 of the refrigeration circuit 30 are open in the side of the housing 3. Thus, it is possible to connect pipes 71, 71', 72, and 72' of, for example, the temperature control target apparatus (load 70) on the user side to the openings (ports) 16a, 14a, 25b, and 25a, respectively.
A drain pan 4 for receiving a leaked circulating liquid is disposed at the bottom of the housing 3. The drain pan 4 is provided with a drain port 5 for discharging the circulating liquid collected in the drain pan 4 to the outside.
As described above, the insulating refrigerant such as a fluorinated liquid is used for the circulating liquid L. The insulating refrigerant (fluorinated liquid) has the property of increasing the volume as the temperature increases. For example, ethylene glycol or water is usable as the circulating liquid L. In the present embodiment, the circulating liquid L in the main tank 20 is sent to the load 70 through a feed passage 16 connecting the main tank 20 and the circulating liquid discharge port 16a and the pipe 71 connecting the circulating liquid discharge port 16a and an inlet port 70a of the load 70. The circulating liquid L that has cooled the load 70 is sent to the heat exchanger 11 through the pipe 71' connecting an outlet port 70b of the load 70 and the circulating liquid return port 14a and a first return passage 14 connecting the circulating liquid return port 14a and the heat exchanger 11 of the temperature control unit 8. The circulating liquid L whose temperature has been controlled in the heat exchanger 11 returns to the main tank 20 again through a second return passage 15 connecting the heat exchanger 11 and the main tank 20. That is, the circulation passage 10 is formed by including the feed passage 16, the pipes 71 and 71', the first return passage 14, the heat exchanger 11, and the second return passage 15.
The feed passage 16 allows an outlet port 20a open in a bottom wall 21 of the main tank 20 and the circulating liquid discharge port 16a to communicate with each other. The pipe 71 allows the circulating liquid discharge port 16a and the inlet port 70a of the load 70 to communicate with each other. The pipe 71' allows the circulating liquid return port 14a and the outlet port 70b of the load 70 to communicate with each other. The first return passage 14 allows the circulating liquid return port 14a and a circulating liquid inlet port 11a of the heat exchanger 11 to communicate with each other. The second return passage 15 allows a circulating liquid outlet port 11b of the heat exchanger 11 and an inlet port 20b open in the bottom wall of the main tank 20 to communicate with each other.
A circulating liquid heat exchange passage 12 connected between the circulating liquid inlet port 11a and the circulating liquid outlet port 11b is provided in the heat exchanger 11. The first return passage 14 and the second return passage 15 communicate with the circulating liquid heat exchange passage 12. In addition, a refrigerant heat exchange passage 13 connected between a refrigerant inlet port 11c and a refrigerant outlet port 11d is provided in the heat exchanger 11. A third circulation passage 36 and a fourth circulation passage 37, which are described later, of the refrigeration circuit (heat exchange circuit) 30 are connected to the refrigerant heat exchange passage 13. The circulating liquid flowing in the circulating liquid heat exchange passage 12 exchanges heat with the refrigerant flowing in the refrigerant heat exchange passage 13 and is controlled so as to have a predetermined temperature. The circulating liquid controlled so as to have a predetermined temperature returns from the circulating liquid outlet port 11b of the heat exchanger 11 to the main tank 20 through the second return passage 15.
The first return passage 14 is provided with, in the order from the upstream side toward the downstream side, a flow rate sensor 14b and a temperature sensor 14c for detecting the flow rate and the temperature of the circulating liquid L. The sensors 14b and 14c are electrically connected to the control unit 60. In addition, the feed passage 16 is provided with, in the order from the upstream side toward the downstream side, a pressure sensor 16b and a temperature sensor 16c for detecting the pressure and the temperature of the circulating liquid L. The sensors 16b and 16c are also electrically connected to the control unit 60.
The main tank 20 includes an upper part having an opening, is defined by the bottom wall 21 and a side wall 22, and stores the circulating liquid L therein. On the other hand, the sub tank 40 has a first end 40a and a second end 40b on respective sides in the width direction, is defined by a bottom wall 41, a side wall 42, and an upper wall 43, has a larger capacity than the main tank 20, houses the entire main tank 20 therein, and stores the circulating liquid L therein. The main tank 20 is located closer to the first end 40a of the sub tank 40 and is disposed in an upper part of the sub tank 40 with a gap above the bottom wall 21 of the main tank 20. Thus, a space portion 44 is formed around the main tank 20 in the sub tank 40. In the present embodiment, the space portion 44 includes a lower space portion 44a, which is formed between the bottom wall 41 of the sub tank 40 and the bottom wall 21 of the main tank 20, a side space portion 44b, which is formed closer to the second end 40b of the sub tank 40, and an upper space portion 44c, which is formed above the main tank 20.
The circulating liquid L is stored in the lower space portion 44a. The heat exchanger 11 is disposed in the side space portion 44b. Various sensors to be described later are disposed in the upper space portion 44c.
The refrigeration circuit 30 of the temperature control unit 8 includes a compressor 31, which is configured to compress a gas refrigerant into a high-temperature, high-pressure gas refrigerant, the condenser 32, which is configured to cool the high-temperature, high-pressure gas refrigerant sent from the compressor 31 into a low-temperature, high-pressure liquid refrigerant, a first expansion valve 33, which is configured to decompress the low-temperature, high-pressure liquid refrigerant sent from the condenser 32 into a low-temperature, low-pressure liquid refrigerant, and the heat exchanger 11 (evaporator), which is configured to heat the low-temperature, low-pressure liquid refrigerant sent from the first expansion valve 33 into a high-temperature, low-pressure gas refrigerant. In the present embodiment, the heat exchanger 11 is part of the circulation passage 10 and is also part of the refrigeration circuit 30.
The refrigeration circuit 30 includes a first refrigerant passage 34, which connects an outlet port 31b of the compressor 31 and an inlet port 32a of the condenser 32, a second refrigerant passage 35, which connects an outlet port 32b of the condenser 32 and an inlet port 33a of the first expansion valve 33, a third refrigerant passage 36, which connects an outlet port 33b of the first expansion valve 33 and the refrigerant inlet port 11c of the heat exchanger 11, and a fourth refrigerant passage 37, which connects the refrigerant outlet port 11d of the heat exchanger 11 and an inlet port 31a of the compressor 31. The second refrigerant passage 35 is provided with, in the order from the upstream side toward the downstream side, a pressure sensor 35a, a high-pressure sensor 35b, and a filter 35c. The pressure sensor 35a and the high-pressure sensor 35b are also electrically connected to the control unit 60.
In addition, a fifth refrigerant passage 38 connecting the part of the third refrigerant passage 36 downstream of the first expansion valve 33 and the first refrigerant passage 34 is provided therebetween. The fifth refrigerant passage 38 is provided with a second expansion valve 27. In addition, a sixth refrigerant passage 39 connecting the part of the second refrigerant passage 35 downstream of the filter 35c and the compressor 31 is provided therebetween. The sixth refrigerant passage 39 is provided with a third expansion valve 28. Then, the second expansion valve 27 is capable of controlling the function of the heat exchanger 11 to regulate the temperature of the circulating liquid L by using the refrigerant. The third expansion valve 28 is capable of preventing overheating of the compressor 31. The compressor 31, the first expansion valve 33, the second expansion valve 27, and the third expansion valve 28 are also electrically connected to the control unit 60. The control unit 60 controls the compressor 31, the first expansion valve 33, the second expansion valve 27, and the third expansion valve 28.
In the present embodiment, the condenser 32 is a water-cooled condenser disposed along an outer surface of the side wall 42 of the sub tank 40 and is provided with a heat dissipating circuit 25, in which industrial water flows. The heat dissipating circuit 25 includes a heat dissipating water supply passage 25c, which connects the heat dissipating water supply port 25a and a heat dissipating water inlet port 32c of the condenser 32, and a heat dissipating water discharge passage 25d, which connects the heat dissipating water discharge port 25b and a heat dissipating water outlet port 32d of the condenser 32. The heat dissipating water discharge passage 25d is provided with a sluice valve 25e. The sluice valve 25e is also electrically connected to the control unit 60. The control unit 60 controls the opening degree of the sluice valve 25e, thus enabling control of the refrigerant temperature. The condenser 32 may be an air-cooled condenser.
The sub tank 40 is provided with the supply pump 51 configured to supply the circulating liquid L in the sub tank 40 into the main tank 20. In the present embodiment, the supply pump 51 is an immersible pump configured to draw the circulating liquid L in the sub tank 40 into the main tank 20 and is disposed in the side space portion 44b closer to the second end 40b of the sub tank 40 so as to extend in an up-down direction. A discharge port 51a for discharging the drawn circulating liquid L in the sub tank 40 into the main tank 20 is open in an upper part of the supply pump 51. The supply pump 51 is also electrically connected to the control unit 60.
Three level switches 52, 53, and 54 are provided in the sub tank 40. The level switch 52 is provided at a position below and close to the upper wall 43 of the sub tank 40. The level switch 53 is provided at a position below and close to the bottom wall 21 of the main tank 20. The level switch 54 is provided above the bottom wall 41 of the sub tank 40. In the present embodiment, the level switches 52, 53, and 54 are float-type level switches and are electrically connected to the control unit 60. Details of the float-type level switches will be described later. In addition, the part of the side wall 42 closer to the first end 40a of the sub tank 40 is provided with a level gauge 45, which enables the amount of the circulating liquid L in the sub tank 40 to be visually checked from the outside of the housing 3, and a circulating liquid injection port 46 for supplying the circulating liquid L to the sub tank 40 from the outside of the housing 3.
In addition, a discharge pipe 47 extending outward is provided at the bottom of the part of the side wall 42 closer to the first end 40a of the sub tank 40. A drain cock 47a is attached to a tip end portion of the discharge pipe 47. The circulating liquid L in the sub tank 40 can be discharged to the outside by opening the drain cock 47a. Of the three level switches 52, 53, and 54, the level switch 52 disposed at the position below and close to the upper wall 43 detects the level of the circulating liquid L when the sub tank 40 is substantially full of the circulating liquid L. In addition, the level switch (upper limit level sensor) 53 disposed at the position below and close to the bottom wall 21 of the main tank 20 detects the upper limit position where the level of the circulating liquid L stored in the sub tank 40 does not reach the bottom of the main tank 20. In addition, the level switch 54 disposed at the bottom of the inside of the sub tank 40 detects the lower limit level of the circulating liquid L stored in the sub tank 40. Then, when the three level switches 52, 53, and 54 detect the respective levels of the circulating liquid L in the sub tank 40, the processor 61 gives an alarm for urging the circulating liquid to be supplied from the circulating liquid injection port 46 to the sub tank 40 and an alarm for urging the drain cock 47a to open to discharge the circulating liquid L from the sub tank 40. Details of the alarms will be described later.
The main tank 20 is provided with the immersible circulating pump 23 configured to send the circulating liquid L to the feed passage 16 of the circulation passage 10. Then, the circulating pump 23 is also electrically connected to the control unit 60. In addition, the upper wall 43 of the sub tank 40 is provided with the heater 24 (temperature control unit 8) configured to heat the circulating liquid L above the middle position in the up-down direction of the circulating liquid L stored in the main tank 20. In addition, the upper wall 43 of the sub tank 40 is provided with a thermal fuse 26 disposed in the upper space portion 44c above the main tank 20. The heater 24 and the thermal fuse 26 are also electrically connected to the control unit 60. Thus, for example, when the temperature of air in the main tank 20 becomes higher than a predetermined temperature, the processor 61 determines that the circulating liquid L is in an overheated state and is thus capable of turning off the power of the temperature regulating device 1.
In addition, the upper wall 43 of the sub tank 40 is provided with two level switches 55 and 56 disposed in the up-down direction in an upper part of the inside of the main tank 20. The level switches 55 and 56 are also electrically connected to the control unit 60. Then, the level switches 55 and 56 are capable of detecting the level of the circulating liquid L in the main tank 20. Of the two level switches 55 and 56, the level switch 55 (first level detection sensor) disposed above detects the level of the circulating liquid L in the main tank 20. Thus, the processor 61 enables detection of leakage of the circulating liquid L from the temperature regulating device 1. The leakage of the circulating liquid L from the temperature regulating device 1 will be described later. The level switch 56 is disposed below the level switch 55 and detects the lower limit level of the circulating liquid L stored in the main tank 20.
As illustrated in Figs. 1 and 2, a communication hole 22a is open in an upper part of the side wall 22 of the main tank 20 closer to the first end 40a of the sub tank 40. The communication hole 22a passes through the side wall 22 and communicates with a gap 48 formed between the side wall 22 of the main tank 20 and the side wall 42 of the sub tank 40 facing the side wall 22. The gap 48 extends in the up-down direction and communicates with the circulating liquid injection port 46 and the lower space portion 44a. Thus, the circulating liquid L discharged from the communication hole 22a returns to the inside of the sub tank 40 through the gap 48. Then, the communication hole 22a enables the level of the circulating liquid L in the main tank 20 to be maintained at the same position as the position of the communication hole 22a.
Hereinafter, the position of the communication hole 22a in the main tank 20 is referred to as a "liquid level reference position Ps". In the present embodiment, the communication hole 22a has an opening extending in the up-down direction. Thus, the liquid level reference position Ps is defined as the position of the lower end of the communication hole 22a. The liquid level reference position Ps is a reference position when starting detection of leakage of the circulating liquid L from the temperature regulating device 1. The liquid level reference position Ps may be defined by the upper edge of the side wall 22 of the main tank 20. In this case, the communication hole 22a is unnecessary.
The level switch 55 is disposed at a position at a predetermined distance h downward from the liquid level reference position Ps. For example, the predetermined distance h is defined in consideration of the amount of the circulating liquid L leaked from the temperature regulating device 1 per unit time.
As described above, the level switches 52 to 56 are, for example, float-type level switches. The level switches 52 to 56 have the same structure. Thus, the level switch 55 will be described below. In the float-type level switch 55, a magnet is set on an inner surface of a float 55a, and a reed switch is disposed in a stem 55b supporting the float 55a so as to be movable. The level switch 55 is configured such that the reed switch turns on and off due to the magnetic field of the magnet when the float 55a moves upward and downward relative to the stem 55b. In addition, the stem 55b is provided with stoppers (not illustrated) for restricting the upward and downward movement of the float 55a on the respective upper and lower sides of the float 55a. The level switch 56 is disposed below the level switch 55 and detects the lower limit level of the circulating liquid L stored in the main tank 20.
Next, the control unit 60 including the processor 61 configured to execute the leakage detection process of detecting leakage of the circulating liquid L will be described.
As illustrated in Figs. 1 and 5, when the temperature regulating device 1 starts operation, the processor 61 executes a circulating liquid temperature monitoring process of monitoring whether the temperature of the circulating liquid L in the main tank 20 detected by the temperature sensor 16c satisfies a predetermined condition (step 1). Here, in the present embodiment, the predetermined condition is that the state in which the temperature of the circulating liquid L detected by the temperature sensor 16c is maintained at a preset temperature continues for a predetermined time (third predetermined time, for example, three hours). Then, when the detected temperature of the circulating liquid L does not satisfy the set temperature in the circulating liquid temperature monitoring process, the step 1 is repeated. When the temperature of the circulating liquid L does not satisfy the set temperature, the processor 61 may control the temperature of the refrigerant flowing in the heat exchanger 11 of the refrigeration circuit 30 to control the temperature of the circulating liquid L or may control the temperature of the circulating liquid L in the main tank 20 by using the heater 24. In addition, the set temperature may be settable so as to have a predetermined tolerance.
Then, when the circulating liquid L satisfies the predetermined condition in the circulating liquid temperature monitoring process, the process proceeds to a step 2, and the processor 61 causes the level switch 55 to start detection of the level of the circulating liquid L. Then, the processor 61 causes the supply pump 51 to be driven for a preset time (second set time, for example, four seconds) to supply the circulating liquid in the sub tank 40 to the main tank 20 (step 3). Accordingly, for example, the level of the circulating liquid L in the main tank 20 is displaced upward from the state in which the level of the circulating liquid L is detected by the level switch 55 (see Fig. 3) and reaches the liquid level reference position Ps (see Fig. 4). Even when the level of the circulating liquid L supplied to the main tank 20 tries to exceed the liquid level reference position Ps during driving of the supply pump 51, the circulating liquid L flows out from the communication hole 22a into the sub tank 40. Thus, it is possible to maintain the level of the circulating liquid L in the main tank 20 at the liquid level reference position Ps.
Then, in synchronization with the end of supply of the circulating liquid L from the supply pump 51, the processor 61 resets a timer configured to calculate an elapsed time (step 4) and starts the leakage detection process (steps 5 to 7).
When the processor 61 starts the leakage detection process, the processor 61 determines whether the temperature of the circulating liquid L detected by the temperature sensor 16c satisfies the set temperature (step 5). Then, when the temperature of the circulating liquid L satisfies the set temperature, the leakage detection process continues and proceeds to the step 6. When the temperature of the circulating liquid L does not satisfy the set temperature, the leakage detection process stops to return to the step 1, and the circulating liquid temperature monitoring process is then executed.
In the step 5, when the temperature of the circulating liquid L satisfies the set temperature, the process proceeds to the step 6, and the processor 61 determines whether the level of the circulating liquid L in the main tank 20 is detected by the level switch 55. Then, when the processor 61 determines that the level of the circulating liquid L in the main tank 20 is not detected by the level switch 55, the process proceeds to the step 7, and the processor 61 determines whether the time elapsed from when the timer is reset exceeds a preset first set time (for example, one hour). Then, when the processor 61 determines that the elapsed time is within the first set time, the process returns to the step 5, and the processor 61 continues the leakage detection process.
On the other hand, in the leakage detection process, when the processor 61 determines that the level of the circulating liquid L in the main tank 20 is detected by the level switch 55 (step 6), the process proceeds to the step 8, and the processor 61 determines that the circulating liquid L is leaked from the temperature regulating device 1 and outputs a first alarm signal. Here, when the processor 61 outputs the first alarm signal, the processor 61 is capable of causing, for example, a display and a speaker provided in the control unit 60 to output an indication and a sound for notifying leakage of the circulating liquid L and is capable of stopping the operation of the temperature regulating device 1.
In this manner, in the leakage detection process, the level switch 55 detects a change in the level of the circulating liquid L within the first predetermined time. Thus, it is possible to accurately grasp a change in the amount of the circulating liquid L flowing between the load 70 and the temperature regulating device 1. Accordingly, the processor 61 is capable of outputting the first alarm signal by determining that the circulating liquid L is leaked from the temperature regulating device 1 on the basis of the detection of the level of the circulating liquid L by the level switch 55.
In addition, in the step 6, when the processor 61 determines that the level of the circulating liquid L in the main tank 20 is not detected by the level switch 55, the processor 61 causes the supply pump 51 to be driven for the second set time to supply the circulating liquid L in the sub tank 40 to the main tank 20 in the case of the time elapsed from when the timer is reset exceeding the first set time (for example, one hour) (step 7). Thus, the processor 61 causes the level of the circulating liquid L in the main tank 20 to reach the liquid level reference position Ps and restarts the leakage detection process.
Meanwhile, when the level switch 53 (upper limit level sensor) provided in the sub tank 40 detects that the level of the circulating liquid in the sub tank 40 is located at the upper limit position during the operation of the temperature regulating device 1, the processor 61 determines that there is a possibility of contact of the circulating liquid L in the sub tank 40 with the main tank 20 and outputs a second alarm signal. This is because, when the circulating liquid L in the sub tank 40 comes into contact with the main tank 20, there is a possibility of a change in the temperature of the circulating liquid L in the main tank 20 due to heat exchange between the circulating liquid L in the sub tank 40 and the circulating liquid L in the main tank 20. In this case, similarly to the case of the first alarm signal, the processor 61 is capable of causing, for example, a display and a speaker provided in the control unit 60 to output an indication and a sound for notifying the contact of the circulating liquid with the main tank 20 and is capable of stopping the operation of the temperature regulating device 1.
As described above, according to the temperature regulating device 1, it is possible to provide the temperature regulating device 1 capable of accurately grasping a change in the amount of the circulating liquid L flowing between the temperature regulating device 1 and the load 70 by detecting the level of the circulating liquid L in the main tank 20 by using the level switch 55 within the first predetermined time in the leakage detection process and capable of early detecting leakage of the circulating liquid L.
The above embodiment illustrates the temperature control unit 8 including the refrigeration circuit 30 (heat exchange circuit) configured to supply, to the heat exchanger 11, the refrigerant to be subjected to heat exchange with the circulating liquid L, but the configuration is not limited thereto. The temperature control unit 8 may include a heat exchange circuit in which the heat dissipating water supply passage 25c and the heat dissipating water discharge passage 25d of the heat dissipating circuit 25 are connected to the heat exchanger 11 so as to be able to directly supply cooling water to the heat exchanger 11.

Reference Signs List

1: temperature regulating device
8: temperature control unit
10: circulation passage
11: heat exchanger (temperature control unit)
14: first return passage (return passage)
15: second return passage (return passage)
16: feed passage
16c: temperature sensor
20: main tank
22: side wall
22a: communication hole
22b: upper edge
23: circulating pump
24: heater (temperature control unit)
30: refrigeration circuit (temperature control unit, heat exchange circuit)
40: sub tank
51: supply pump
53: level switch (upper limit level sensor)
55: level switch (first level detection sensor)
60: control unit
61: processor
70: load
L: circulating liquid
Ps: liquid level reference position

Claims

A temperature regulating device for regulating a temperature of a load so as to be a predetermined set temperature, the temperature regulating device comprising:
a main tank storing a circulating liquid for regulating the temperature of the load;

a circulation passage through which the circulating liquid in the main tank is sent to the load and that receives the circulating liquid that has regulated the temperature of the load to send the circulating liquid to the main tank;

a circulating pump configured to send the circulating liquid in the main tank to the load through the circulation passage;

a temperature control unit that is provided to the circulation passage and that is configured to control a temperature of the circulating liquid that has regulated the temperature of the load; and

a control unit including a processor configured to execute a leakage detection process of detecting leakage of the circulating liquid, wherein

the main tank includes
a first level detection sensor configured to detect a level of the circulating liquid stored in the main tank, and

a liquid level reference position where the leakage detection process starts, the liquid level reference position being located at a position above the first level detection sensor, and

when the level in the main tank is detected by the first level detection sensor within a preset first set time in the leakage detection process, the processor determines that the circulating liquid is leaked from the temperature regulating device and outputs a first alarm signal.
The temperature regulating device according to claim 1, wherein
the temperature control unit includes
a heat exchanger configured to exchange heat with the circulating liquid, and

a heat exchange circuit configured to supply, to the heat exchanger, a heat exchange medium to be subjected to heat exchange with the circulating liquid.
The temperature regulating device according to claim 1, further comprising:
a sub tank in which the main tank is disposed and that stores the circulating liquid; and

a supply pump configured to supply the circulating liquid in the sub tank into the main tank, wherein

the liquid level reference position is defined by
a communication hole that passes through a side wall of the main tank and that allows an inside of the main tank and an inside of the sub tank to communicate with each other, or

an upper edge of the side wall of the main tank.
The temperature regulating device according to claim 3, wherein
when the level in the main tank is not detected by the first level detection sensor within the first set time in the leakage detection process, the processor causes the level of the circulating liquid in the main tank to reach the liquid level reference position by driving the supply pump for a preset second set time and by supplying the circulating liquid in the sub tank to the main tank and restarts the leakage detection process.
The temperature regulating device according to claim 3, wherein
the circulation passage includes
a feed passage for sending the circulating liquid in the main tank to the load, the feed passage being connected to the main tank, and

a return passage that receives the circulating liquid that has regulated the temperature of the load to return the circulating liquid to the main tank,

the feed passage of the circulation passage is provided with a temperature sensor configured to detect a temperature of the circulating liquid sent from the main tank, and

when the temperature regulating device starts operation, the processor executes a circulating liquid temperature monitoring process of monitoring whether the temperature of the circulating liquid detected by the temperature sensor satisfies a predetermined condition, and when the temperature of the circulating liquid satisfies the predetermined condition in the circulating liquid temperature monitoring process, the processor causes the level of the circulating liquid in the main tank to reach the liquid level reference position by driving the supply pump for a preset second set time and by supplying the circulating liquid in the sub tank to the main tank and starts the leakage detection process.
The temperature regulating device according to claim 5, wherein
the predetermined condition is that a state in which the temperature of the circulating liquid detected by the temperature sensor is maintained at the set temperature continues for a preset third predetermined time.
The temperature regulating device according to claim 5 or 6, wherein
when the temperature of the circulating liquid detected by the temperature sensor does not satisfy the set temperature during execution of the leakage detection process, the processor stops the leakage detection process and executes the circulating liquid temperature monitoring process.
The temperature regulating device according to claim 3, wherein
the sub tank is provided with an upper limit level sensor configured to detect an upper limit position where a level of the circulating liquid stored in the sub tank does not reach a bottom of the main tank, and

when the upper limit position is detected by the upper limit level sensor, the processor determines that there is a possibility of contact of the circulating liquid in the sub tank with the main tank and outputs a second alarm signal.