Refrigeration apparatus, method for controlling a refrigeration apparatus, exposure apparatus, and method for manufacturing articles

Abstract

This provides a refrigeration system that is advantageous for detecting filter clogging. [Solution] A refrigeration device comprising: a refrigerant circuit including a condenser; a detector disposed in the refrigerant circuit for detecting the state of the refrigerant in the refrigerant circuit; a control valve for adjusting the cooling water flowing into the condenser through piping; and a control unit for adjusting the state of the refrigerant by controlling the opening degree of the control valve. The control unit notifies the user that the first opening degree value has reached a preset second opening degree value when the first opening degree value, which is the opening degree of the control valve after it has fluctuated and then remained within a specified range for a certain period of time, reaches a preset second opening degree value.

Description

[Technical Field]

[0001] The present invention relates to a refrigeration apparatus, a method for controlling a refrigeration apparatus, an exposure apparatus, and a method for manufacturing articles. [Background technology]

[0002] In a refrigeration system that cools an object by circulating a refrigerant through a compressor, condenser, expansion valve, and evaporator, the refrigerant absorbs heat from the object being cooled in the evaporator, and this heat is then discharged outside the refrigeration system in the condenser. There are two types of condensers: air-cooled condensers and water-cooled condensers. Small refrigeration systems with low heat output use air-cooled condensers, which discharge heat by exchanging heat with air, while large refrigeration systems use water-cooled condensers, which discharge heat by exchanging heat with water. When a refrigeration system is used, for example, to cool the heat generated in an exposure system, a large amount of heat is required, so water-cooled condensers are often used.

[0003] Patent Document 1 discloses a method for detecting clogging of a filter installed in piping. A flow meter and a flow control valve are installed in the piping to which the filter is installed, and the flow control valve is opened and closed to maintain the flow rate of the fluid flowing through the piping at a preset flow rate. Under these conditions, if clogging of the filter occurs, the flow control valve will gradually open in order to maintain a constant value without reducing the fluid flow rate. Clogging of the filter is detected when the opening of the flow control valve is fully open or reaches a preset opening.

[0004] If the cooling water contains particles (foreign matter), these particles can get caught in the valve drive mechanism of the cooling water control valve, causing the valve to seize and malfunction. If the cooling water control valve does not operate, the refrigeration system will not be able to properly cool the object being cooled. For example, in the case of an exposure system, this could result in defective products. Therefore, when the cooling water control valve stops working, the exposure system must be temporarily shut down and the cooling water control valve replaced with a working one. As a result, production of goods cannot be carried out until the exposure system is restored, which can cause significant losses.

[0005] To prevent the cooling water control valve from malfunctioning, it is effective to install a particle-collecting filter upstream of the valve. However, if the filter is used for a long period of time, most of it will become clogged, and even if the cooling water control valve is fully opened, the required amount of cooling water will not be obtained. In such a situation, the cooling equipment will not be able to adequately cool the object being cooled, leading to production defects. Therefore, it is desirable to properly determine when the filter should be replaced and replace the filter with a new, working one during equipment maintenance.

[0006] Water-cooled condensers are equipped with a cooling water control valve to adjust the amount of water used for heat exchange. When there is a large amount of heat to be released, the control valve is opened to allow more cooling water to flow into the condenser, and conversely, when there is a small amount of heat to be released, the control valve is closed. Furthermore, the amount of heat to be released may be adjusted by reducing the amount of water required for heat exchange when the water temperature is low, and increasing the amount of water when the water temperature is high. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 06-018401 [Overview of the project] [Problems that the invention aims to solve]

[0008] When a refrigeration system including a water-cooled condenser is used in an exposure system, the temperature and volume of the cooling water supplied from the factory equipment are not constant but may fluctuate. Furthermore, during exposure, the amount of heat generated in the exposure system increases, the amount of heat discharged in the water-cooled condenser increases, and a large amount of cooler water is required. In this way, even if a filter is installed upstream of the cooling water control valve in the refrigeration system and the clogging detection method described in Patent Document 1 is adopted, it is not possible to set the amount of cooling water to flow to the condenser to a predetermined value in advance, and therefore it is not possible to detect clogging of the filter.

[0009] Therefore, the present invention provides a refrigeration device that is advantageous in detecting clogging of a filter.

Means for Solving the Problems

[0010] In order to achieve the above object, a refrigeration device according to an aspect of the present invention includes a refrigerant circuit including a condenser, a detector disposed in the refrigerant circuit for detecting the state of the refrigerant in the refrigerant circuit, a regulating valve for regulating cooling water flowing into the condenser through a pipe, and a control unit for adjusting the state of the refrigerant by controlling the opening degree of the regulating valve. The control unit notifies the user that the first opening degree value, which is the opening degree when the opening degree of the regulating valve is within the range of a specified value for a certain period after the opening degree of the regulating valve has fluctuated, has reached a second opening degree value set in advance.

Advantages of the Invention

[0011] According to the present invention, a refrigeration device that is advantageous in detecting clogging of a filter can be provided.

Brief Description of the Drawings

[0012] [Figure 1] It is a diagram showing the configuration of a refrigeration device according to Embodiment 1. [Figure 2] It is a relational diagram of the opening degree of a cooling water regulating valve and a condensing pressure value when the heat load on the refrigeration device changes. [Figure 3] It is a relational diagram of the cooling water temperature, the opening degree of the cooling water regulating valve, and the condensing pressure value. [Figure 4] It is a relational diagram of the cooling water amount, the opening degree of the cooling water regulating valve, and the condensing pressure value. [Figure 5] It is a graph when the opening degree data of the cooling water regulating valve is plotted against the elapsed time. [Figure 6] It is a relational diagram of the clogging rate of the filter, the opening degree of the cooling water regulating valve, and the condensing pressure value. [Figure 7] It is a flowchart showing the processing of the refrigeration device according to Embodiment 1. [Figure 8]This graph shows the result of fitting a least-squares approximation line to the opening degree data of the cooling water control valve when the filter is becoming clogged. [Figure 9] This figure shows the filter arrangement and piping configuration for resolving filter clogging according to Embodiment 2. [Figure 10] This figure shows the flow of cooling water to clear clogging of the filter according to Embodiment 2. [Figure 11] This is a schematic diagram showing the configuration of the exposure apparatus according to Embodiment 3. [Modes for carrying out the invention]

[0013] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0014] <Embodiment 1> Figure 1 shows the configuration of the refrigeration system 10 of Embodiment 1. The refrigeration system 10 includes a refrigerant circuit (refrigerant piping) 20, a high-pressure acquisition unit 21, a low-pressure acquisition unit 22, and a control unit 23.

[0015] The refrigerant circuit 20 is configured to include a compressor 11, a condenser 12, an expansion valve 13, and an evaporator 14. The refrigerant circuit 20 is composed of conduits or piping. In this embodiment, the compressor 11, condenser 12, expansion valve 13, and evaporator 14 are positioned relative to the refrigerant circuit 20 as shown in Figure 1. The configuration of the refrigerant circuit 20 and the refrigerant circulating inside the refrigerant circuit 20 will be described below with reference to Figure 1.

[0016] The refrigerant circulating within the refrigerant circuit 20 is compressed into a gaseous state by the compressor 11 and flows to the condenser 12. Cooling water is connected to the condenser 12, and the high-temperature gaseous refrigerant compressed by the compressor 11 is cooled (dissipated heat) by the cooling water, causing the gaseous refrigerant to condense into a liquid refrigerant. A cooling water control valve 15 is provided in the condenser 12 to control the flow rate of the cooling water flowing in. In other words, the cooling water control valve 15 can adjust the flow rate of cooling water flowing into the condenser 12 through the piping.

[0017] The condensed refrigerant is expanded by the expansion valve 13 and, through heat exchange with the object to be cooled (e.g., air) in the evaporator 14, evaporates into a gaseous refrigerant and returns to the compressor 11. The object to be cooled by the evaporator 14 is heated and adjusted by the heater 24 before being supplied to the object to be cooled.

[0018] The temperature acquisition means 30 measures the supply temperature to the object being cooled. The temperature acquisition means 30 is composed of, for example, a temperature sensor. The temperature acquisition means 30 is positioned in front of the object being cooled, specifically near the object being cooled at a position just before the object is struck by the heated object, which has been heated and adjusted by the heater 24. The heating output of the heater 24 is then adjusted so that the temperature acquired by the temperature acquisition means 30 is a predetermined temperature. The adjustment of the heating output in the heater 24 is performed by the control unit 23, which will be described later.

[0019] The refrigeration system 10 has a high-pressure acquisition unit 21 and a low-pressure acquisition unit 22, which are detectors located in the refrigerant circuit 20 and detect the state of the refrigerant in the refrigerant circuit 20. The high-pressure acquisition unit 21 is configured to include a pressure sensor that measures the high pressure of the refrigerant circulating inside the refrigerant circuit 20. The low-pressure acquisition unit 22 is configured to include a pressure sensor that measures the low pressure of the refrigerant circulating inside the refrigerant circuit 20.

[0020] Furthermore, instead of the high-pressure acquisition unit 21, a high-temperature acquisition unit 31 that measures the temperature of the high-temperature side of the refrigerant circulating inside the refrigerant circuit 20 may be placed in the refrigerant circuit 20. In addition, instead of the low-pressure acquisition unit 22, a low-temperature acquisition unit 32 that measures the temperature of the cold-temperature side of the refrigerant circulating inside the refrigerant circuit 20 may be placed in the refrigerant circuit 20. In that case, the high-temperature acquisition unit 31 and the low-temperature acquisition unit 32 will function as detectors. Furthermore, the high-pressure acquisition unit 21 and the high-temperature acquisition unit 31, and the low-pressure acquisition unit 22 and the low-temperature acquisition unit 32 may be placed in the refrigerant circuit, respectively. In that case, it is preferable to place the high-temperature acquisition unit 31 in a location that does not interfere with the measurement of the high-pressure pressure of the refrigerant by the high-pressure acquisition unit 21, and the low-temperature acquisition unit 32 in a location that does not interfere with the measurement of the low-pressure pressure of the refrigerant by the low-pressure acquisition unit 22.

[0021] In this embodiment, since measuring pressure is often preferable to measuring temperature as a means of understanding the refrigerant state in the refrigerant circuit 20, the configuration in which a high-pressure acquisition unit 21 and a low-pressure acquisition unit 22 are arranged in the refrigerant circuit 20 will be described below.

[0022] The control unit 23 is at least one computer including a CPU and memory, and comprehensively controls the refrigeration system 10 and processes various data of the refrigeration system 10. The control unit 23 also controls the operation and processing of each component of the entire refrigeration system 10 according to a program stored in memory. Furthermore, as shown in Figure 1, the control unit 23 may be configured separately from the refrigeration system 10 (in a separate enclosure), or it may be configured as an integral part of the refrigeration system 10 (in a common enclosure). It may also be installed in a separate location from the refrigeration system 10 and controlled remotely. Note that the control unit 23 is not limited to one CPU or memory; there may be multiple CPUs and memory units. In other words, the control unit 23 is configured as a computer including one or more CPUs and memory units.

[0023] The control unit 23 controls the opening of the expansion valve 13 and the cooling water control valve 15 in order to control the refrigerant pressure acquired by the high-pressure acquisition unit 21 and the low-pressure acquisition unit 22 to a predetermined value (adjust the state of the refrigerant). That is, for example, the control unit 23 takes the refrigerant pressure after passing through the condenser 12 as a high-pressure value (hereinafter referred to as the condensation pressure value), and controls the high-pressure value to a predetermined value by adjusting the opening of the cooling water control valve 15 to control the flow rate of the cooling water. By controlling in this way, even if the amount of heat entering the refrigeration system 10 (hereinafter referred to as the heat load) changes and the amount of heat to be discharged to the cooling water changes, the amount of heat to be discharged can be adjusted without measuring the temperature or volume of the cooling water. Even if the temperature or volume of the cooling water supplied as power changes, the amount of opening and closing of the cooling water control valve 15 changes according to that change, so that the required amount of heat can be discharged. On the other hand, the refrigerant pressure after passing through the evaporator 14 is low, and by adjusting the opening of the expansion valve 13 so that this low pressure value becomes a predetermined value, the object to be cooled can be cooled without excess or deficiency regardless of changes in the heat load on the refrigeration system 10. The control unit 23 stores the operating status of the refrigeration system 10, including the information acquired by the high-pressure acquisition unit 21 and the low-pressure acquisition unit 22, in a storage medium such as memory.

[0024] In this embodiment, a filter 16 is placed upstream of the cooling water control valve 15 to protect the cooling water control valve 15 by capturing particles (foreign matter) contained in the cooling water. That is, as shown in Figure 1, the cooling water control valve 15 is placed between the filter 16 and the condenser 12. The filter 16 removes particles (foreign matter) contained in the cooling water flowing into the condenser 12 by capturing them, thereby preventing particles from flowing into the condenser 12.

[0025] The filter 16 has a mesh structure, and if the number of squares contained within one side of a 25.4 mm x 25.4 mm square in the mesh is n, it is identified as an n-mesh filter. The smaller the drive resolution of the cooling water control valve 15, the finer the high pressure value of the refrigerant can be adjusted. However, this also increases the risk that if minute particles enter the valve drive unit (not shown) that drives the cooling water control valve 15, the valve will seize up and become inoperable. It is desirable to determine the mesh number n by first investigating the maximum particle size that can be tolerated for the cooling water control valve 15 to be used through durability testing.

[0026] In this embodiment, before the filter 16 becomes clogged to the point where the condenser 12 can no longer obtain the necessary amount of cooling water, the alarm device 33 (notification means) issues an alarm (provides notification). Specifically, the control unit 23 controls the alarm device 33 to emit a warning sound or a corresponding voice message to notify the user that the filter 16 is clogged and to urge them to replace the filter. In addition to alarm sounds and voice messages, the alarm device 33 may also notify the user that the filter 16 is clogged and to urge them to replace the filter by displaying a message on the screen of a predetermined display means. Furthermore, alarm sounds and voice messages may be combined with notifications displayed on the screen. The notification means connected to the refrigeration system 10 is connected, for example, via an internet connection. Therefore, even if the user is located away from the refrigeration system 10, they can receive notifications from the alarm device 33 and recognize the clogging of the filter 16 early.

[0027] FIG. 2 is a graph showing an example of the transition of the opening degree of the cooling water control valve 15 when the heat load applied to the refrigeration apparatus 10 changes. The horizontal axis of the graph represents the elapsed time, and the vertical axis represents, in order from the top of the graph, the heat load applied to the refrigeration apparatus 10, the opening degree of the cooling water control valve 15, and the condensation pressure value of the refrigeration apparatus 10. The opening degree of the cooling water control valve 15 is defined as 0% when fully closed and 100% when fully open. When the heat load applied to the refrigeration apparatus 10 is small, let the amount of that heat load be Q1. At this time, it is necessary to exhaust the total heat amount obtained by adding the heat amount of the heat load Q1 received by the refrigerant in the evaporator 14 of the refrigeration apparatus 10 and the driving heat amount of the compressor 11 to the cooling water in the condenser 12.

[0028] If the heat can be exhausted to the cooling water without excess or deficiency, the gaseous refrigerant before entering the condenser 12 changes to a liquid refrigerant and takes a predetermined condensation pressure value P cond . If the opening degree of the cooling water control valve 15 is not optimal and the heat exhaust amount is not appropriate, the condensation pressure value takes a value other than P cond . For example, when the condensation pressure value is greater than P cond , since the heat exhaust is insufficient and the refrigerant temperature is still high, the cooling water control valve 15 is controlled to open until the condensation pressure value reaches P cond . Let the opening degree of the cooling water control valve 15 when the condensation pressure value stabilizes at P cond be V1. In the refrigeration apparatus 10, the opening degree of the cooling water control valve 15 is controlled by the control unit 23 so that the condensation pressure value always becomes P cond . In actual operation, it is not necessary for the condensation pressure value to exactly match P cond all the time, and it is considered acceptable as long as it falls within the range of the allowable pressure fluctuation with respect to the value of P cond .

[0029] When the amount of heat received by the refrigerant in the evaporator 14 increases, the heat load increases to Q2, but the cooling water control valve 15 opens so that the condensation pressure value becomes P cond , and the valve opening degree becomes V2. Even when the heat load condition changes to a larger heat load Q3, the cooling water control valve 15 opens further and the valve opening degree becomes V3, and the condensation pressure value is maintained at P cond . Thus, regardless of the magnitude of the heat load applied to the refrigeration apparatus 10, the condensation pressure value is P condBy controlling the opening degree of the cooling water control valve 15 to maintain this state, the amount of heat that should be released into the cooling water is released without excess or deficiency.

[0030] Figure 3 is a graph showing an example of the change in the opening degree of the cooling water control valve 15 when the temperature of the cooling water supplied to the refrigeration unit 10 changes. When the cooling water temperature is T4, the condensation pressure value is P cond The opening degree of the cooling water control valve 15 that stabilizes is set to V4. If the cooling water temperature rises to T5 from this state, the amount of heat that can be released into the cooling water by the condenser 12 decreases, so the condensation pressure value is P cond It tends to change in the direction of increasing pressure. The condensation pressure value is P cond To maintain this, the cooling water control valve 15 opens to valve opening V5, allowing more cooling water to flow to the condenser 12 for heat exchange with the refrigerant of the refrigeration system 10. In this way, regardless of changes in cooling water temperature, the condensation pressure value P cond By controlling the opening degree of the cooling water control valve 15 to maintain this state, the amount of heat that should be released into the cooling water is released without excess or deficiency.

[0031] Figure 4 is a graph showing an example of the change in the opening degree of the cooling water control valve 15 when the amount (or water pressure) of cooling water supplied to the refrigeration unit 10 changes. When the amount of cooling water is F6, the condensation pressure value is P cond The opening degree of the cooling water control valve 15 that stabilizes is set to V6. If the amount of cooling water decreases to F7 from this state, the amount of heat that can be released into the cooling water by the condenser 12 decreases, so the condensation pressure value is P cond It tends to change in the direction of increasing pressure. The condensation pressure value is P cond To maintain this, the cooling water control valve 15 opens to valve opening V7, allowing more cooling water to flow to the condenser 12 for heat exchange with the refrigerant of the refrigeration system 10. In this way, regardless of the change in the amount of cooling water, the condensation pressure value P cond By controlling the opening degree of the cooling water control valve 15 to maintain this state, the amount of heat that should be released into the cooling water is released without excess or deficiency.

[0032] Figure 5 is a graph plotting the opening degree data of the cooling water control valve 15 against elapsed time. When the opening degree of the cooling water control valve 15 changes, strictly speaking, as shown in the upper part of Figure 5, it stabilizes at a nearly constant opening degree after some fluctuation. If the opening degree value when this opening degree stabilizes (first opening degree value) is stored in memory and plotted with time on the horizontal axis, the situation will be as illustrated in the lower part of Figure 5. It is preferable to select a cooling water control valve 15 such that the opening degree of the cooling water control valve 15 takes a value of approximately 50% even when the heat load conditions and cooling water temperature change. When determining that the opening degree is stable, for example, it may be determined that the opening degree is stable if, after the opening degree has fluctuated, it has remained within a predetermined range of specified values ​​(within a predetermined threshold) for a certain period of time.

[0033] Figure 6 is a graph showing an example of the changes in the clogging rate of filter 16, the opening degree of the cooling water control valve 15, and the condensation pressure value. Here, the clogging rate is defined as 0% for a state where filter 16 is not clogging, and 100% for a state where it is clogging to the point where the cooling water can no longer flow. Up to elapsed time T1, the filter 16 is not clogging, and the opening degree of the cooling water control valve 15 and the condensation pressure value are the same as the state shown in Figure 5. Now, let's assume that at elapsed time T1, for example, some change occurs on the factory equipment side, and the cooling water begins to contain particles larger than the mesh size of filter 16, causing filter 16 to start to clog.

[0034] When filter 16 becomes clogged, the amount of cooling water flowing into condenser 12 decreases, resulting in insufficient heat dissipation. The required amount of heat dissipates to set the condensation pressure to P. cond To maintain this state, the opening of the cooling water control valve 15 gradually increases after the elapsed time T1. If the opening of the cooling water control valve 15 is fixed at 100%, the required amount of cooling water will be insufficient, and the condensation pressure value will be P condThis can lead to a loss of control. As a result, the cooling device 10 may not be able to adequately cool the object to be cooled, potentially leading to production defects. Thus, the opening degree of the cooling water control valve 15 can fluctuate due to external factors, such as particles larger than the mesh size of the filter 16 being included in the cooling water, as described above.

[0035] Therefore, in this embodiment, the opening degree (opening degree value) of the cooling water control valve 15 is set to a value slightly smaller than 100%. alarm (Example: set to approximately 90%). Then, the opening degree of the cooling water control valve 15 is set to V for the first time. alarm When the above value is recorded (V alarm When the condition is met, the control unit 23 determines that the filter 16 is clogged. After determining that the filter is clogged, the control unit 23 controls the alarm device 33 to notify the user that the filter needs to be replaced (that the filter 16 needs to be replaced with a new one). The control unit 23 determines whether the filter 16 is clogged not immediately after the opening of the cooling water control valve 15 changes, but only after the opening has changed and remained within a predetermined range for a certain period of time. The following explanation will be given with reference to Figure 7.

[0036] Figure 7 is a flowchart showing the determination process and notification process for whether or not filter replacement is necessary, performed by the refrigeration system 10 in this embodiment. Each operation (process) shown in the flowchart of Figure 7 is executed (controlled) by the CPU of the control unit 23 of the refrigeration system 10 executing a program stored in memory. In addition, the notation of each process (step) is omitted by adding an S at the beginning of each step.

[0037] In S101, the control unit 23 determines whether the opening degree of the cooling water control valve 15 has changed. If the determination shows that the opening degree of the cooling water control valve 15 has changed, the process proceeds to S102. On the other hand, if the opening degree of the cooling water control valve 15 has not changed, the process waits until the opening degree of the cooling water control valve 15 changes. Here, the control unit 23 may determine whether the opening degree of the cooling water control valve 15 has changed based on a predetermined threshold. For example, the control unit 23 determines that the opening degree of the cooling water control valve 15 has changed if the change exceeds a preset threshold. Any value can be set for the predetermined threshold. For example, the control unit 23 may determine that the opening degree of the cooling water control valve 15 has changed if it has changed by 0.5%, 1%, or 5% from the opening degree before the determination. Furthermore, it is assumed that the opening degree of the cooling water control valve 15 will fluctuate due to external factors, such as particles larger than the mesh size of the filter 16 being included in the cooling water, as described above.

[0038] In S102, the control unit 23 determines whether the opening degree of the cooling water control valve 15 has stabilized. If the determination shows that the opening degree of the cooling water control valve 15 is stable, the process proceeds to S103. On the other hand, if the opening degree of the cooling water control valve 15 is not stable, this process is repeated until the opening degree of the cooling water control valve 15 stabilizes. The determination of whether the opening degree of the cooling water control valve 15 has stabilized is made, for example, if the opening degree has remained within a predetermined range (within a predetermined threshold) for a certain period of time after fluctuating.

[0039] Furthermore, in addition to determining whether the opening degree of the cooling water control valve 15 has stabilized in the S102 process, the control unit 23 may also determine whether it has detected an abnormality in the high-pressure acquisition unit 21 or the low-pressure acquisition unit 22, which functions as a detector. In that case, if the opening degree of the cooling water control valve 15 is stable and no abnormality has been detected in the high-pressure acquisition unit 21 or the low-pressure acquisition unit 22, the process proceeds to S103. On the other hand, if the opening degree of the cooling water control valve 15 is not stable, this process is repeated until the opening degree of the cooling water control valve 15 stabilizes. Also, if an abnormality is detected in the high-pressure acquisition unit 21 or the low-pressure acquisition unit 22, the process waits until the abnormality is no longer detected. Here, if an abnormality is detected in the high-pressure acquisition unit 21 or the low-pressure acquisition unit 22, the control unit 23 may control the alarm device 33 to notify the user of this fact.

[0040] In S103, the control unit 23 determines whether the opening value of the cooling water control valve 15 after its opening has stabilized (first opening value) has reached a preset threshold value (second opening value). If the determination shows that the first opening value of the cooling water control valve 15 has reached the second opening value, the process proceeds to S104. That is, the control unit determines whether the opening value (first opening value) of the cooling water control valve 15, after its opening has fluctuated and remained within a predetermined range (within a predetermined threshold) for a certain period of time, has reached a preset threshold value (second opening value). Furthermore, if the first opening value of the cooling water control valve 15 has reached the second opening value, the control unit 23 also determines that the filter 16 is clogged. In addition, if the control unit 23 determines that the filter 16 is clogged, it also determines that the filter 16 needs to be replaced. On the other hand, if the first opening value of the cooling water control valve 15 has not reached the second opening value, the process returns to S101 and the same procedure is performed.

[0041] In S104, the control unit 23 controls the alarm device 33 to notify the user that the first opening value has reached the second opening value (that the filter is clogged) (notification step). Alternatively, it notifies the user to replace the filter (that the filter 16 needs to be replaced with a new one). The control unit 23 may notify the user of both that the first opening value has reached the second opening value and that it is urging the user to replace the filter. The control unit 23 may also notify the user of at least one of the above by voice, such as that the first opening value has reached the second opening value and that it is urging the user to replace the filter. Alternatively, the control unit 23 may notify the user of at least one of the above by displaying it on the screen of the display device. The control unit 23 may also notify the user of the above by combining voice and screen display. After informing the user that the first opening value has reached the second opening value, and prompting the user to replace the filter, the process shown in Figure 7 is terminated.

[0042] Thus, after the opening degree of the cooling water control valve 15 fluctuates, if the first opening degree value, which is the opening degree when it has remained within a specified range for a certain period of time, reaches a preset second opening degree value, the control unit 23 notifies the user that the first opening degree value has reached the second opening degree value. In other words, after the opening degree of the cooling water control valve 15 fluctuates due to external factors, if the opening degree (first opening degree value) when the control has stabilized (the opening degree has stabilized) reaches a preset opening degree (second opening degree value), the control unit 23 determines that the filter 16 is clogged. After this determination, the control unit 23 controls the alarm device 33 to notify the user of this fact (that the first opening degree value has reached the second opening degree value). That is, the control unit 23 controls the alarm device 33 to notify the user to replace the filter 16.

[0043] Furthermore, if it is determined in S102 whether an abnormality has been detected in the high-pressure acquisition unit 21 or the low-pressure acquisition unit 22, which functions as a detector, the following processing is performed. The control unit 23 does not detect an abnormality in the output of the detector, and after the opening degree of the cooling water control valve 15 has fluctuated due to external factors, the first opening degree value, which is the opening degree at which it has remained within a specified range for a certain period of time, reaches a preset second opening degree value, and provides a predetermined notification. The predetermined notification is the same as above, informing the user that the first opening degree value has reached a preset second opening degree value.

[0044] If an alarm is issued at elapsed time T1, but the user fails to notice and replace the filter 16, the opening of the coolant control valve 15 will continue to increase and eventually become fixed at 100%. If the elapsed time at this point is T2, then the amount of coolant will be insufficient thereafter, and the condensation pressure value will be P cond If the pressure continues to rise, the object to be cooled will not be able to be cooled sufficiently, which may lead to production defects. Furthermore, if the refrigerant pressure continues to rise, there is a risk of damage to the piping of the refrigerant circuit 20 and the various components that make up the refrigeration unit 10. Therefore, the pre-set upper limit P alarm When this condition is reached, the control unit 23 forcibly stops the operation of the refrigeration unit 10 to protect it.

[0045] In Embodiment 1, even when the heat load conditions and cooling water conditions applied to the refrigeration system 10 fluctuate, the condensation pressure value of the refrigerant in the refrigeration system 10 is P cond The control unit 23 adjusts the opening of the cooling water control valve 15 to maintain the desired level and monitors its opening value. Specifically, if the opening of the cooling water control valve 15 fluctuates due to external factors and the control stabilizes, and the opening (first opening value) reaches a preset opening (second opening value), the control unit 23 determines that the filter 16 is clogged and notifies the user accordingly. This facilitates the detection of filter 16 clogging, thereby preventing cooling water shortages and damage to various equipment.

[0046] <Embodiment 2> In Embodiment 2, the method by which the control unit 23 predicts the replacement time of the filter 16 will be described below with reference to Figure 8. Note that the configuration of the refrigeration system 10 in Embodiment 2 is the same as that of the refrigeration system 10 in Embodiment 1, so similar points will not be explained.

[0047] Figure 8 is a graph obtained by fitting a least-squares approximation line to the opening degree data of the cooling water control valve when clogging is progressing in the filter. In the graph of Figure 8, the slope a and intercept b of the following equation (1) are calculated by applying a least-squares approximation to the plot data (v,t) of elapsed time t and the opening degree (opening degree value) v of the cooling water control valve 15 from elapsed time T1 onwards.

number

[0048] The opening degree V of the cooling water control valve 15 when an alarm is triggered in the above equation (1) alarm Substituting this value gives an estimated elapsed time T for when filter 16 should be replaced. alarm This can be predicted by the following equation (2).

number

[0049] T calculated using the above formula (2) alarm The alarm device 33 notifies the user in advance, allowing the user to prepare a new filter 16 beforehand and replace the filter 16 during equipment maintenance.

[0050] As described above, according to the refrigeration system 10 of Embodiment 2, a least-squares approximation line is calculated between the opening value of the cooling water control valve 15 and the usage time of the filter 16 to estimate the replacement time of the filter 16. This makes it possible to determine the replacement time of the filter 16 before it becomes clogged, and, as with Embodiment 1, it is possible to suppress cooling water shortages and damage to various equipment.

[0051] <Embodiment 3> In this embodiment, a method for clearing clogging of the filter 16 without stopping the production of goods by the device and without replacing the filter 16 with a new one will be described with reference to Figures 9 and 10. Note that the configuration of the refrigeration device 10 in Embodiment 3 is the same as that of the refrigeration device 10 in Embodiment 1, so the explanation of the similarities will be omitted.

[0052] Figure 9 shows a structure that can clear the clogging of filter 16. Figure 10 shows the flow of cooling water to clear the filter clogging.

[0053] In Figures 9 and 10, the solid lines represent the piping 17 through which the cooling water flows. In Embodiment 3, two filters and four three-way valves are provided outside the refrigeration unit 10. Specifically, the piping 17 connected to the refrigeration unit 10 is equipped with a first filter 16a and a second filter 16b, as well as a first three-way valve 18a, a second three-way valve 18b, a third three-way valve 18c, and a fourth three-way valve 18d. The second filter 16b is a different filter from the first filter 16a. In the figures, the thick solid lines represent the piping 17 through which the cooling water actually flows. The thin solid lines represent piping through which the cooling water does not flow.

[0054] The control unit 23 in Embodiment 3 switches the flow path of the cooling water by performing first control and second control. In other words, the control unit 23 switches the flow path of the cooling water from the first flow path to the second flow path, or from the second flow path to the first flow path, by controlling multiple switching valves (multiple three-way valves). The first flow path will be described below.

[0055] In the first flow path, the cooling water first passes through the first three-way valve 18a, the first filter 16a, and the second three-way valve 18b during the first control, and then through the cooling water control valve 15 and the condenser 12. After that, the cooling water passes through the third three-way valve 18c, the second filter 16b, and the fourth three-way valve 18d during the first control before being discharged to the outside. The discharged cooling water returns to the factory equipment side, for example. Thus, in the first control which is the first flow path, the control unit 23 controls each three-way valve (first three-way valve 18a to fourth three-way valve 18d) so that the water passes through in the order of first filter 16a, cooling water control valve 15, condenser 12, and second filter 16b.

[0056] In this type of cooling water flow, particles (foreign matter) are collected by the first filter 16a on the outward path, and the cleaned (foreign matter removed) cooling water flows to the second filter 16b on the return path. Therefore, the possibility of particles accumulating on the second filter 16b through which the cooling water passes on the return path is very low. In the case of the first flow path, the first filter 16a functions as a filter on the outward path side, and the second filter functions as a filter on the return path side.

[0057] In this configuration, as the cooling water continues to flow, clogging progresses in the first filter 16a, which the water passes through on the outward path. In Embodiment 3, as in Embodiment 1, when the opening value (first opening value) of the cooling water control valve 15 reaches a preset opening value (second opening value), the control unit 23 determines that the first filter 16a is clogged and controls the alarm device 33 to issue an alarm.

[0058] When the control unit 23 determines that the filter 16 is clogged, it controls the switching of multiple three-way valves as shown in Figure 10 to switch the flow path of the cooling water. Specifically, the flow path of the cooling water is switched by rotating the ball members having L-shaped flow paths provided in the first three-way valve 18a, the second three-way valve 18b, the third three-way valve 18c, and the fourth three-way valve 18d. In Embodiment 3, the switching of each of these three-way valves is performed by the control unit 23, but for example, the switching of the three-way valve 18 may be performed manually by an operator.

[0059] By performing control to switch the cooling water flow path, that is, control to switch from the first flow path to the second flow path (second control), the cooling water flow path (first flow path) is changed as shown in Figure 10, and the cooling water flows through the changed flow path (second flow path). In the case of the second flow path, the cooling water first passes through the first three-way valve 18a, the second filter 16b, and the second three-way valve 18b during the second control, and then passes through the cooling water control valve 15 and the condenser 12. After that, the cooling water passes through the third three-way valve 18c, the first filter 16a, and the fourth three-way valve 18d during the second control and is discharged to the outside. The discharged cooling water returns to the factory equipment side, for example. Thus, in the second control that switches the first flow path to the second flow path, the control unit 23 controls each three-way valve (first three-way valve 18a to fourth three-way valve 18d) so that the water passes through the second filter 16b, the cooling water control valve 15, the condenser 12, and the first filter 16a in that order.

[0060] By changing the flow path of the cooling water in this way, particles can be collected by the second filter 16b while the particles collected by the first filter 16a are discharged. In other words, particles are now collected by the second filter 16b, which was not used for collection in the flow path shown in Figure 9. As a result, clean cooling water flows into the first filter 16a, which has become clogged, from the opposite direction to before the three-way valve was switched as shown in Figure 9, allowing particles to be discharged towards the factory equipment, thus resolving the clogging of the first filter 16a.

[0061] Furthermore, if the clogging of the second filter 16b progresses and the opening value (first opening value) of the cooling water control valve 15 reaches a preset opening value (second opening value), the control unit 23 determines that the second filter 16b is clogged, controls the alarm device 33, and issues an alarm.

[0062] In other words, the control unit 23 controls multiple three-way valves to switch the flow path from the second flow path to the first flow path. By repeatedly switching the flow path in this way, particles are collected by a filter other than the one that has become clogged, and the clogged filter can be discharged to the factory equipment side by clean cooling water flowing in from the opposite direction. Thus, the control unit 23 of Embodiment 3 controls multiple switching valves (three-way valves) that switch the flow path of the cooling water in the piping 17 where the first filter 16a and the second filter 16b, which collect particles contained in the cooling water flowing into the condenser 12, are located. In other words, if the control unit 23 determines that either the first filter 16a or the second filter 16b has become clogged, it controls multiple switching valves (three-way valves) to repeatedly switch the flow path of the cooling water.

[0063] As described above, according to the refrigeration device 10 of Embodiment 3, multiple three-way valves are controlled to repeatedly switch between the first flow path and the second flow path. This makes it possible to eliminate filter clogging without stopping the production of goods and without replacing the two filters (first filter 16a and second filter 16b) with new ones.

[0064] <Embodiment 4> In Embodiment 4, an example in which the refrigeration device 10 described above is mounted on the exposure device 100 will be described below with reference to Figure 11. Note that the configuration of the refrigeration device 10 in Embodiment 3 is the same as the configuration of the refrigeration device 10 in Embodiment 1, so the explanation of the similarities will be omitted. Figure 11 is a schematic diagram showing the configuration of the exposure device 100 in Embodiment 4.

[0065] The exposure apparatus 100 is used in the lithography process when manufacturing semiconductor devices and devices such as flat panel displays (FPDs). The exposure apparatus 100 forms a latent image pattern on a substrate by transferring the pattern of a mask (master plate) onto a substrate coated with resist. In this embodiment, a step-and-scan type exposure apparatus is described, but it is not limited to this, and other exposure methods such as a step-and-repeat method may also be used.

[0066] The exposure apparatus 100 includes a light source 101, an illumination optical system 102, a mask stage 103, a projection optical system 104, a substrate stage 105, and a refrigeration device 10. The mask stage 103 is a movable stage that holds a mask M. The substrate stage 105 is a movable stage that holds a substrate W. The mask M and the substrate W are positioned optically conjugate via the projection optical system 104. Light emitted from the light source 101 illuminates the mask M via the illumination optical system 102, and the pattern of the mask M is projected onto the substrate W to perform an exposure process that forms a latent image pattern on the resist layer on the substrate W.

[0067] When exposure processing is performed, heat is generated in various parts of the exposure apparatus 100. For example, when exposure light is irradiated onto the optical elements of the projection optical system 104, some of the energy of the exposure light is absorbed, generating heat within the projection optical system 104. Also, when the substrate stage 105 is driven during the exposure processing to change the exposure area, heat is generated in components such as the linear motor used to perform the drive. Furthermore, heat is also generated when the transport robot 106, which transports the mask M and substrate W, is driven. The heat generated in various parts of the exposure apparatus 100 can cause a decrease in exposure performance. Therefore, in order to keep the various parts of the exposure apparatus 100 within an appropriate temperature range, temperature-controlled air is supplied to the exposure apparatus 100 by a blower 108 in a machine room 107 consisting of a refrigeration system 10 and a heater 24 to recover the heat.

[0068] In this case, if the cooling water control valve 15 of the refrigeration unit 10 is stopped by particles, the heat generated in the exposure unit 100 will not be able to be properly discharged, which will lead to defects in the produced goods, and therefore the operation of the exposure unit 100 must be stopped.

[0069] Therefore, by using the refrigeration device 10 described in Embodiments 1 to 3 in the exposure device 100 in this embodiment, the time for replacing the filter 16 can be detected early. As a result, the time during which the device is shut down can be reduced, and the decrease in productivity can be suppressed.

[0070] Furthermore, the exposure apparatus 100 may be equipped with multiple refrigeration devices 10. In addition to the refrigeration devices 10 described in Embodiment 1, the refrigeration devices 10 described in Embodiments 1 and 3 may also be equipped. Moreover, the methods described in Embodiments 1 to 3 may be combined. The exposure apparatus 100 also has a main control unit (not shown).

[0071] The main control unit is at least one computer including a CPU and memory, and comprehensively controls the exposure apparatus 100. The main control unit also controls the operation and processing of each component of the entire exposure apparatus 100 according to a program stored in memory. The main control unit may be configured as an integral part of the other parts of the exposure apparatus 100 (within a common housing), or as a separate unit (within a separate housing), or it may be installed in a different location from the exposure apparatus 100 and controlled remotely. In addition to controlling the exposure apparatus 100, the main control unit may also control the refrigeration apparatus 10 instead of the control unit 23. Alternatively, the control unit 23 of the refrigeration apparatus 10 may control the exposure apparatus 100 in addition to controlling the refrigeration measures 10.

[0072] Furthermore, the refrigeration device 10 shown in Embodiments 1 to 3 is not limited to being placed in an exposure apparatus. For example, it can be used in an imprint apparatus that performs an imprinting process to sequentially form patterns of imprint material in multiple imprint areas on a substrate coated with imprint material using a mold having a pattern portion. It can also be used in a planarization apparatus that planarizes a composition on a substrate using a planarization member. In other words, the refrigeration device 10 shown in Embodiments 1 to 3 is a device that can be used with each apparatus such as an exposure apparatus, an imprint apparatus, and a planarization apparatus. And as described above, each apparatus may have multiple refrigeration devices 10. In addition, not only the refrigeration device 10 described in Embodiment 1, but also the refrigeration devices 10 described in Embodiments 2 and 3 may be placed. Furthermore, the methods described in Embodiments 1 to 3 may be combined.

[0073] <Embodiment for manufacturing an article> The method for manufacturing an article performed by the exposure apparatus 100 in Embodiment 4 is suitable, for example, for manufacturing an FPD (flat panel display). The method for manufacturing an article in this embodiment includes the steps of: forming a latent image pattern on a photosensitive material coated on a substrate by exposure using the above-mentioned exposure apparatus to obtain an exposure substrate (exposure step); and developing the exposure substrate on which the latent image pattern was formed in the above step to obtain a developed substrate (development step). Furthermore, this manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The method for manufacturing an article in this embodiment is advantageous over conventional methods in at least one of the performance, quality, productivity, and production cost of the article.

[0074] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its essence. Furthermore, the above embodiments may be implemented in combination.

[0075] Furthermore, some or all of the control in each of the embodiments described above may be performed by supplying a computer program that realizes the functions of each embodiment described above to the imprint device 1, etc., via a network or various storage media. The computer (or CPU, MPU, etc.) in that device may then read and execute the program. In that case, the program and the storage medium storing the program constitute the present invention.

[0076] This embodiment includes the following configurations and methods.

[0077] (Composition 1) A refrigerant circuit including a condenser, A detector is placed in the refrigerant circuit and detects the state of the refrigerant in the refrigerant circuit. A control valve that regulates the cooling water flowing into the condenser through piping, The system includes a control unit that adjusts the state of the refrigerant by controlling the opening degree of the control valve, When the control unit reaches a preset second opening value, which is the opening value of the control valve after it has fluctuated and then returned to within a specified range for a certain period of time, the control unit notifies the user that the first opening value has reached the preset second opening value. A refrigeration apparatus characterized by the following features.

[0078] (Configuration 2) The refrigeration apparatus according to configuration 1, characterized in that the control unit determines that the filter for collecting foreign matter contained in the cooling water flowing into the condenser is clogged when the opening value of the control valve reaches a preset opening value after the opening degree of the control valve has fluctuated and the control has stabilized.

[0079] (Composition 3) The refrigeration apparatus according to configuration 2, characterized in that when the control unit determines that the filter is clogged, it controls a notification means that provides a predetermined notification to the user, and notifies the user that the filter should be replaced.

[0080] (Composition 4) The refrigeration apparatus according to configuration 3, characterized in that the control unit controls the notification means and notifies the user by voice that the filter should be replaced.

[0081] (Composition 5) The refrigeration apparatus according to configuration 3 or 4, characterized in that the control unit controls the notification means and notifies the user via a screen display that the filter should be replaced.

[0082] (Composition 6) The refrigeration apparatus according to any one of configurations 1 to 5, characterized in that the control unit does not detect an abnormality in the output of the detector, and when the opening degree of the control valve fluctuates due to external factors and then returns to a predetermined range for a certain period of time, the control unit notifies the user that the opening degree of the control valve has reached a preset second opening degree.

[0083] (Composition 7) The refrigeration apparatus according to any one of configurations 1 to 6, characterized in that the detector includes a high-pressure acquisition unit for measuring the high-pressure pressure of the refrigerant circulating inside the refrigerant circuit and a low-pressure acquisition unit for measuring the low-pressure pressure of the refrigerant circulating inside the refrigerant circuit.

[0084] (Composition 8) The refrigeration apparatus according to any one of configurations 1 to 7, characterized in that the detector includes a high-temperature acquisition unit for measuring the temperature of the high-temperature side of the refrigerant circulating inside the refrigerant circuit, and a low-temperature acquisition unit for measuring the temperature of the cold-temperature side of the refrigerant circulating inside the refrigerant circuit.

[0085] (Composition 9) The refrigeration apparatus according to any one of configurations 1 to 8, characterized in that the control valve is positioned between a filter that collects foreign matter contained in the cooling water flowing into the condenser and the condenser.

[0086] (Composition 10) The refrigeration apparatus according to any one of configurations 1 to 9, characterized in that the control unit calculates a least-squares approximation straight line with respect to the opening value of the control valve and the usage time of the filter that collects foreign matter contained in the cooling water flowing into the condenser, and estimates the time when the filter should be replaced.

[0087] (Composition 11) The refrigeration apparatus according to any one of configurations 1 to 10, characterized in that the control unit controls a plurality of switching valves that switch the flow path of the cooling water in the piping where a first filter and a second filter for collecting foreign matter contained in the cooling water flowing into the condenser are arranged.

[0088] (Composition 12) The control unit controls the plurality of switching valves to switch the flow path from the first flow path to the second flow path or from the second flow path to the first flow path. In the first flow path, the cooling water passes through the first filter and then the second filter in that order, and then the cooling water is discharged to the outside. In the second flow path, the cooling water passes through the second filter and then the first filter in that order, and then the cooling water is discharged to the outside. The refrigeration apparatus according to configuration 11, characterized by the features described above.

[0089] (Composition 13) The control unit switches the flow path by performing the first control and the second control. In the first control, the plurality of switching valves are controlled so that the cooling water passes through in the order of the first filter, the control valve, the condenser, and the second filter. In the second control, the plurality of switching valves are controlled so that the cooling water passes through the second filter, the control valve, the condenser, and the first filter in that order. The refrigeration apparatus according to configuration 11, characterized by the features described above.

[0090] (Composition 14) The refrigeration apparatus according to any one of configurations 11 to 13, characterized in that when the control unit determines that either the first filter or the second filter is clogged, it controls the plurality of switching valves and switches the flow path of the cooling water.

[0091] (Composition 15) A control method for a refrigeration system comprising: a refrigerant circuit including a condenser; a detector disposed in the refrigerant circuit for detecting the state of the refrigerant in the refrigerant circuit; a control valve for adjusting the cooling water flowing into the condenser through piping; and a control unit for adjusting the state of the refrigerant by controlling the opening degree of the control valve, The control valve has a notification step that, when the opening degree of the control valve has fluctuated and then returned to within a specified range for a certain period of time, the first opening degree value, which is the opening degree at that time, reaches a preset second opening degree value, and the first opening degree value reaches a preset second opening degree value. A method for controlling a refrigeration system, characterized by the following features.

[0092] (Composition 16) An exposure apparatus that projects a pattern formed on a master plate onto a substrate and performs exposure processing on the substrate, Having a refrigeration device as described in any one of configurations 1 to 15, An exposure apparatus characterized in that the heat generated during the exposure process is cooled by the refrigeration device.

[0093] (Composition 17) An exposure step to obtain an exposed substrate by exposing the substrate using the exposure apparatus described in configuration 16, The process includes developing the aforementioned photopolymer substrate to obtain a developed substrate, A method for manufacturing an article, characterized by manufacturing an article from the aforementioned developing substrate. [Explanation of symbols]

[0094] 10 Refrigeration equipment 11 Compressor 12 Condenser 13 Expansion valve 14 Evaporator 15 Cooling water control valve 20 Refrigerant Circuit 21 High-pressure pressure acquisition unit 22 Low-pressure pressure acquisition unit 23 Control Unit 33 Alarm device

Claims

1. A refrigerant circuit including a condenser, A detector is placed in the refrigerant circuit and detects the state of the refrigerant in the refrigerant circuit. A control valve that regulates the cooling water flowing into the condenser through piping, The system includes a control unit that adjusts the state of the refrigerant by controlling the opening degree of the control valve, The control unit shall, when the first opening value, which is the opening value of the control valve after it has fluctuated and then returned to within a specified range for a certain period of time, reaches a preset second opening value, notify the user that the first opening value has reached the preset second opening value. A refrigeration apparatus characterized by the following features.

2. The refrigeration apparatus according to claim 1, characterized in that the control unit determines that the filter for collecting foreign matter contained in the cooling water flowing into the condenser is clogged when the opening value of the control valve reaches a preset opening value after the control has stabilized following a fluctuation in the opening degree of the control valve.

3. The refrigeration apparatus according to claim 2, characterized in that, when the control unit determines that the filter is clogged, it controls a notification means that provides a predetermined notification to the user, and notifies the user that the filter should be replaced.

4. The refrigeration apparatus according to claim 3, characterized in that the control unit controls the notification means and notifies the user by voice that the filter should be replaced.

5. The refrigeration apparatus according to claim 3, characterized in that the control unit controls the notification means and notifies the user via a screen display that the filter should be replaced.

6. The refrigeration apparatus according to claim 1, characterized in that the control unit does not detect an abnormality in the output of the detector, and when the opening degree of the control valve fluctuates due to external factors and then returns to a predetermined range for a certain period of time, the first opening degree value reaches a preset second opening degree value, and the control unit notifies the user that the first opening degree value has reached the preset second opening degree value.

7. The refrigeration apparatus according to claim 1, characterized in that the detector includes a high-pressure acquisition unit for measuring the high-pressure pressure of the refrigerant circulating inside the refrigerant circuit and a low-pressure acquisition unit for measuring the low-pressure pressure of the refrigerant circulating inside the refrigerant circuit.

8. The refrigeration apparatus according to claim 1, characterized in that the detector includes a high-temperature acquisition unit for measuring the temperature of the high-temperature side of the refrigerant circulating inside the refrigerant circuit, and a low-temperature acquisition unit for measuring the temperature of the cold-temperature side of the refrigerant circulating inside the refrigerant circuit.

9. The refrigeration apparatus according to claim 1, characterized in that the control valve is positioned between a filter that collects foreign matter contained in the cooling water flowing into the condenser and the condenser.

10. The refrigeration apparatus according to claim 1, characterized in that the control unit calculates a least-squares approximation straight line with respect to the opening value of the control valve and the usage time of the filter that collects foreign matter contained in the cooling water flowing into the condenser, and estimates the time when the filter should be replaced.

11. The refrigeration apparatus according to claim 1, characterized in that the control unit controls a plurality of switching valves that switch the flow path of the cooling water in the piping, in which a first filter and a second filter for collecting foreign matter contained in the cooling water flowing into the condenser are arranged.

12. The control unit controls the plurality of switching valves to switch the flow path from the first flow path to the second flow path or from the second flow path to the first flow path. In the first flow path, the cooling water passes through the first filter and then the second filter in that order, and then the cooling water is discharged to the outside. In the second flow path, the cooling water passes through the second filter and then the first filter in that order, and then the cooling water is discharged to the outside. The refrigeration apparatus according to feature 11.

13. The control unit switches the flow path by performing the first control and the second control. In the first control, the plurality of switching valves are controlled so that the cooling water passes through in the order of the first filter, the control valve, the condenser, and the second filter. In the second control, the plurality of switching valves are controlled so that the cooling water passes through in the order of the second filter, the control valve, the condenser, and the first filter. The refrigeration apparatus according to feature 11.

14. The refrigeration apparatus according to claim 11, characterized in that when the control unit determines that either the first filter or the second filter is clogged, it controls the plurality of switching valves and switches the flow path of the cooling water.

15. A control method for a refrigeration system comprising: a refrigerant circuit including a condenser; a detector disposed in the refrigerant circuit for detecting the state of the refrigerant in the refrigerant circuit; a control valve for adjusting the cooling water flowing into the condenser through piping; and a control unit for adjusting the state of the refrigerant by controlling the opening degree of the control valve, The control valve has a notification step that, when the opening degree of the control valve has fluctuated and then returned to within a specified range for a certain period of time, the first opening degree value, which is the opening degree at that time, reaches a preset second opening degree value, and the first opening degree value reaches a preset second opening degree value. A method for controlling a refrigeration system, characterized by the following features.

16. An exposure apparatus that projects a pattern formed on a master plate onto a substrate and performs exposure processing on the substrate, A refrigeration apparatus according to any one of claims 1 to 15, An exposure apparatus characterized in that the heat generated during the exposure process is cooled by the refrigeration device.

17. An exposure step of exposing a substrate using the exposure apparatus described in claim 16 to obtain an exposed substrate, The process includes developing the aforementioned photopolymer substrate to obtain a developed substrate, A method for manufacturing an article, characterized by manufacturing an article from the aforementioned developing substrate.

Images