阅读说明：本技术 流体供给装置 (Fluid supply device ) 是由 上田祯一郎 猶原康宏 于 2018-08-29 设计创作，主要内容包括：在第1流体循环装置中,利用第1配管将热交换器、贮留由热交换器液化后的第1流体的罐、汲出贮留在罐中的第1流体的第1流体用泵、对从第1流体用泵中汲出的第1流体进行加热的加热器、以及由加热器供给第1流体的第1流体供给部连接。第2流体循环装置具有用于冷却第2流体的冷却器,利用第2配管使由冷却器冷却后的第2流体流通并返回冷却器。第2流体循环装置的第2配管与热交换器连接,并且与罐和第1流体用泵连接,第2流体对热交换器、罐和第1流体用泵中的第1流体进行冷却。第1流体为二氧化碳,第1流体循环装置利用泵将作为第1流体的二氧化碳升压,并且利用加热器将二氧化碳加热,由此生成超临界二氧化碳流体。(In the 1 st fluid circulation device, a heat exchanger, a tank for storing the 1 st fluid liquefied by the heat exchanger, a 1 st fluid pump for pumping out the 1 st fluid stored in the tank, a heater for heating the 1 st fluid pumped out from the 1 st fluid pump, and a 1 st fluid supply unit for supplying the 1 st fluid from the heater are connected by a 1 st pipe. The 2 nd fluid circulation device has a cooler for cooling the 2 nd fluid, and the 2 nd fluid cooled by the cooler is circulated by the 2 nd pipe and returned to the cooler. The 2 nd pipe of the 2 nd fluid circulation device is connected to the heat exchanger, and is also connected to the tank and the 1 st fluid pump, and the 2 nd fluid cools the 1 st fluid among the heat exchanger, the tank, and the 1 st fluid pump. The 1 st fluid is carbon dioxide, and the 1 st fluid circulation device generates a supercritical carbon dioxide fluid by pressurizing the carbon dioxide as the 1 st fluid with a pump and heating the carbon dioxide with a heater.)

1. A fluid supply device is characterized by comprising:

a 1 st fluid circulation device in which a heat exchanger for cooling and liquefying a 1 st fluid, a tank storing the 1 st fluid liquefied by the heat exchanger, a pump drawing the 1 st fluid stored in the tank, a heater heating the 1 st fluid drawn by the pump, and a 1 st fluid supply unit to which the 1 st fluid is supplied by the heater are connected by a 1 st pipe, wherein the 1 st fluid circulation device is switchable between: a state in which the 1 st fluid is caused to flow out toward the heat exchanger after the 1 st fluid is supplied to the 1 st fluid supply portion, or the 1 st fluid is supplied from the heater to the 1 st fluid supply portion, and a state in which the 1 st fluid is caused to flow out toward the heat exchanger by the heater without the 1 st fluid from the heater being supplied to the 1 st fluid supply portion; and

a 2 nd fluid circulating device having a cooler for cooling a 2 nd fluid, the 2 nd fluid cooled by the cooler being circulated by a 2 nd pipe and returned to the cooler,

the 2 nd pipe of the 2 nd fluid circulation device is connected to the heat exchanger, and is connected to the tank and the pump, the 2 nd fluid circulation device cools the 1 st fluid by exchanging heat between the 2 nd fluid and the 1 st fluid in the heat exchanger, and cools the 1 st fluid by exchanging heat between the 2 nd fluid and the 1 st fluid in the tank and the pump,

the 1 st fluid is carbon dioxide and,

the 1 st fluid circulation device is configured to generate a supercritical carbon dioxide fluid by pressurizing the 1 st fluid with the pump and heating the 1 st fluid with the heater.

2. The fluid supply apparatus according to claim 1, wherein the 2 nd pipe circulates the 2 nd fluid in the order of the pump, the tank, and the heat exchanger.

3. The fluid supply apparatus according to claim 1 or 2, wherein the 2 nd pipe includes: a pump connection unit connected to the pump so that the 1 st fluid can be cooled by the 2 nd fluid in the pump; and a pump bypass unit that bypasses the pump connection unit and sends the 2 nd fluid to the downstream side without flowing through the pump.

4. The fluid supply apparatus according to any one of claims 1 to 3,

the pump comprises a housing main body and a pump cover mounted in a state of being closely contacted with the housing main body, a cooling sleeve is formed on the pump cover,

the 2 nd pipe is connected to a cooling jacket of the pump cover.

5. The fluid supply apparatus according to any one of claims 1 to 4,

the tank has a tank main body and a tank cover attached in close contact with the tank main body, the tank cover is provided with a cooling jacket,

the 2 nd pipe is connected to the cooling jacket of the tank cover.

6. The fluid supply apparatus according to any one of claims 1 to 5, wherein the 2 nd fluid is an aqueous ethylene glycol solution, an alcohol antifreeze solution, or a fluorine refrigerant.

7. The fluid supply apparatus according to claim 6,

the 2 nd fluid circulation device is further provided with a 2 nd fluid heater for heating the 2 nd fluid cooled by the cooler, the 2 nd pipe is connected to the heat exchanger, the tank, and the pump on a downstream side of the 2 nd fluid heater,

the fluid supply device further includes: a temperature sensor that detects a temperature of the 1 st fluid in a portion of the 1 st pipe that is downstream of the pump and upstream of the heater; and a controller for adjusting the heating amount of the 2 nd fluid heater based on the detection result of the temperature sensor.

Technical Field

The present invention relates to a fluid supply device suitably used for supplying a fluid such as a supercritical fluid.

Background

Examples of the fluid required to precisely control the temperature to a desired temperature include saline water for cooling a stage holding a wafer, and a supercritical fluid expected to be used in various fields such as cleaning. A supercritical carbon dioxide fluid, which is an example of a supercritical fluid, can be generated by pressurizing liquefied carbon dioxide with a pump and then heating the pressurized carbon dioxide with a heater. As an apparatus for generating such a supercritical carbon dioxide fluid, a circulation type generating apparatus has been known. This apparatus generally includes, in addition to a pump and a heater, a cooling unit that cools and liquefies a supercritical carbon dioxide fluid after cleaning or the like, and a tank that stores liquefied carbon dioxide. This makes it possible to repeatedly generate a supercritical carbon dioxide fluid by raising the pressure and heating the liquefied carbon dioxide again by the pump and the heater (for example, JP2014-101241 a).

It is known that the dissolving power of the supercritical carbon dioxide fluid described above increases and decreases according to the change in density, and the density thereof changes according to the temperature. Therefore, in order to obtain a desired dissolving power, it is required to control the temperature of the supercritical carbon dioxide fluid with high accuracy. In this case, it is important to maintain the temperature of the liquefied carbon dioxide before heating or pressure raising at a desired temperature.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fluid supply device capable of stably maintaining the temperature of a fluid at a desired temperature.

Means for solving the problems

The fluid supply device of the present invention is characterized by comprising: a 1 st fluid circulation device in which a heat exchanger for cooling and liquefying a 1 st fluid, a tank for storing the 1 st fluid liquefied by the heat exchanger, a pump for pumping out the 1 st fluid stored in the tank, a heater for heating the 1 st fluid pumped out by the pump, and a 1 st fluid supply unit for supplying the 1 st fluid from the heater are connected by a 1 st pipe, wherein the 1 st fluid circulation device is switchable between: a state in which the 1 st fluid is supplied to the 1 st fluid supply portion and then the 1 st fluid is caused to flow out toward the heat exchanger, or the 1 st fluid is supplied from the heater to the 1 st fluid supply portion, and a state in which the 1 st fluid is caused to flow out toward the heat exchanger by the heater without supplying the 1 st fluid from the heater to the 1 st fluid supply portion; a 2 nd fluid circulation device having a cooler for cooling a 2 nd fluid, the 2 nd fluid cooled by the cooler being circulated by a 2 nd pipe and returned to the cooler, the 2 nd pipe of the 2 nd fluid circulation device being connected to the heat exchanger and at least one of the tank and the pump, the 2 nd fluid circulation device cooling the 1 st fluid by exchanging heat between the 2 nd fluid and the 1 st fluid in the heat exchanger and cooling the 1 st fluid by exchanging heat between the 2 nd fluid and the 1 st fluid in at least one of the tank and the pump.

According to the fluid supply apparatus of the present invention, even if the 1 st fluid cooled by the 2 nd fluid in the heat exchanger is raised in temperature before reaching the tank or the pump, the temperature rise can be suppressed in the tank and/or the pump by cooling by the 2 nd fluid. This enables the temperature of the fluid (1 st fluid) to be stably maintained at a desired temperature, particularly between the pump and the heater.

The 2 nd pipe may circulate the 2 nd fluid in the tank, the pump, and the heat exchanger in this order.

According to this configuration, since the freezing capacity of the 2 nd fluid at a position close to the heater can be greatly ensured, it is easy to control the temperature of the 1 st fluid to a desired temperature desired to be supplied to the heater.

The 2 nd pipe may circulate the 2 nd fluid in the order of the pump, the tank, and the heat exchanger.

According to this configuration, since the freezing capacity of the 2 nd fluid at a position close to the heater can be greatly secured, the temperature of the 1 st fluid can be easily controlled to a desired temperature desired to be supplied to the heater, and the stability of temperature control can be improved by increasing the cooling target portion.

Further, the 2 nd pipe may include: a pump connection unit connected to the pump so that the 1 st fluid can be cooled by the 2 nd fluid in the pump; and a pump bypass unit that bypasses the pump connection unit and sends the 2 nd fluid to a downstream side without flowing through the pump.

According to this configuration, the presence or absence of cooling of the pump or the refrigerating capacity of the pump can be adjusted by providing an on-off valve or a flow rate adjustment valve in the pump connection portion and/or the pump bypass portion.

The pump may include a housing main body and a pump cover attached to the housing main body in a state of being in close contact with the housing main body, the pump cover may be formed with a cooling jacket, and the 2 nd pipe may be connected to the cooling jacket of the pump cover.

According to this configuration, it is possible to easily suppress a temperature increase of the 1 st fluid due to heat release of the drive source of the pump.

The tank may include a tank main body and a tank cover attached to the tank main body in a state of being in close contact with the tank main body, the tank cover may be formed with a cooling jacket, and the 2 nd pipe may be connected to the cooling jacket of the tank cover.

According to this configuration, the 1 st fluid in the tank can be easily cooled.

The 1 st fluid may be carbon dioxide, and the 1 st fluid circulation device may be configured to generate a supercritical carbon dioxide fluid by pressurizing the 1 st fluid with the pump and heating the 1 st fluid with the heater.

With this configuration, the supercritical carbon dioxide fluid can be stably generated.

Effects of the invention

According to the present invention, the temperature of the fluid can be stably maintained at a desired temperature.

Drawings

Fig. 1 is a schematic view of a fluid supply apparatus according to embodiment 1 of the present invention.

Fig. 2 is a schematic cross-sectional view of a pump of the 1 st fluid circulation device in the fluid supply device shown in fig. 1.

Fig. 3 is a schematic sectional view of a tank of the 1 st fluid circulation device in the fluid supply device shown in fig. 1.

Fig. 4 is a schematic view of a fluid supply apparatus according to embodiment 2 of the present invention.

Fig. 5 is a schematic view of a fluid supply apparatus according to embodiment 3 of the present invention.

Fig. 6 is a schematic view of a fluid supply apparatus according to embodiment 4 of the present invention.

Fig. 7 is a diagram showing a modification of embodiment 1.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the drawings.

< embodiment 1 >

Fig. 1 is a schematic view of a fluid supply apparatus 1 according to embodiment 1 of the present invention. The fluid supply device 1 of the present embodiment is configured as a device that generates and supplies a supercritical carbon dioxide fluid, for example. As shown in fig. 1, the fluid supply apparatus 1 includes a 1 st fluid circulation device 10 that circulates carbon dioxide, and a 2 nd fluid circulation device 20 that circulates a refrigerant for cooling the carbon dioxide circulating in the 1 st fluid circulation device 10.

The carbon dioxide circulated in the 1 st fluid circulating device 10 corresponds to the 1 st fluid of the present invention, and the refrigerant circulated in the 2 nd fluid circulating device 20 corresponds to the 2 nd fluid of the present invention. The fluid circulated by the 1 st fluid circulation device 10 is not limited to carbon dioxide, and may be brine or the like. The refrigerant circulating in the 2 nd fluid circulation device 20 is an ethylene glycol aqueous solution, but the refrigerant is not limited to this, and may be another alcohol antifreeze, a fluorine refrigerant, or the like.

The 1 st fluid circulation device 10 is configured by connecting a heat exchanger 11, a tank 12, a 1 st fluid pump 13, a heater 14, and a 1 st fluid supply unit 15 by a 1 st pipe 16 including a plurality of pipe bodies, wherein the heat exchanger 11 functions as a condenser for cooling and liquefying carbon dioxide, the tank 12 stores the carbon dioxide cooled and liquefied by the heat exchanger 11, the 1 st fluid pump 13 draws the liquefied carbon dioxide stored in the tank 12 and boosts the pressure of the liquefied carbon dioxide, the heater 14 heats the liquefied carbon dioxide drawn and boosted by the 1 st fluid pump 13 to prepare a supercritical carbon dioxide fluid, and the 1 st fluid supply unit 15 supplies the supercritical carbon dioxide fluid from the heater 14.

The 1 st fluid supply unit 15 and the heat exchanger 11 are connected to each other by a part of the 1 st pipe 16, and the 1 st fluid supply unit 15 uses the supplied supercritical carbon dioxide fluid for a specific purpose and then flows out toward the heat exchanger 11. The above-mentioned specific purpose may be, for example, cleaning, drying, etc. That is, the 1 st fluid supply unit 15 may be, for example, a cleaning tank for cleaning with the supercritical carbon dioxide fluid, or may be a container, chamber, or the like for drying with the supercritical carbon dioxide fluid.

The 2 nd fluid circulation device 20 includes a cooler 21 for cooling the refrigerant, and is configured to circulate the refrigerant cooled by the cooler 21 through a 2 nd pipe 22 including a plurality of pipe bodies, for example, and return the refrigerant to the cooler 21. The illustrated cooler 21 is a heat exchanger, and the refrigerant flowing through the inside thereof is cooled by another refrigerant separately supplied from an external device. Such other refrigerant may be, for example, a refrigerant circulating in a refrigerator.

In fig. 1, reference numeral 31 denotes a refrigerant pipe through which another refrigerant for cooling the refrigerant circulating in the 2 nd fluid cycle device 20 flows, and the refrigerant pipe 31 is connected to the cooler 21. The refrigerant pipe 31 is provided with a flow rate adjustment valve 32 for adjusting the flow rate of the other refrigerant flowing into the cooler 21. In the present embodiment, the temperature of the refrigerant circulating in the 2 nd fluid circulation device 20 can be adjusted by adjusting the opening degree of the flow rate adjustment valve 32.

The 2 nd pipe 22 is provided with a 2 nd fluid pump 23 that generates a driving force for flowing the refrigerant, and a refrigerant heater 24 that heats the refrigerant. In the present embodiment, the refrigerant discharged from the 2 nd fluid pump 23 flows in the direction indicated by the arrow in the figure in the order of the cooler 21 and the refrigerant heater 24.

Here, the 2 nd pipe 22 of the 2 nd fluid circulation device 20 in the present embodiment is connected to the heat exchanger 11 of the 1 st fluid circulation device 10, and is connected to the tank 12 and the 1 st fluid pump 13 at a portion downstream of the refrigerant heater 24 and upstream of the 2 nd fluid pump 23 (a portion downstream of the cooler 21 and upstream). Thus, in the present embodiment, the 2 nd fluid circulation device 20 cools and liquefies the supercritical carbon dioxide fluid by exchanging heat between the refrigerant and carbon dioxide (mainly, in the present example, the supercritical carbon dioxide fluid) in the heat exchanger 11, and cools the supercritical carbon dioxide fluid by exchanging heat between the refrigerant and carbon dioxide (mainly, in the present example, liquefied carbon dioxide) also in the tank 12 and the 1 st fluid pump 13.

Fig. 2 is a schematic cross-sectional view of the 1 st fluid pump 13 for explaining a connection mode between the 1 st fluid pump 13 and the 2 nd pipe 22. The 1 st fluid pump 13 includes: an impeller 131 rotated by an unillustrated motor; a casing main body 132 that houses an impeller 131 as a drive unit and that causes a carbon dioxide fluid to flow in and be discharged as the drive unit drives; and a pump cover 133 detachably attached in a state of being closely attached to the casing main body 132, and a plurality of cooling jackets 134 are formed in the pump cover 133. Here, the 2 nd pipe 22 is connected to the cooling jacket 134 of the pump cover 133. Thereby, the refrigerant supplied from the 2 nd pipe 22 to the cooling jacket 134 cools the liquefied carbon dioxide inside the casing main body 132 by the cooling jacket 134 and the casing main body 132.

In the present embodiment, the casing main body 132 is cylindrical, and the pump cover 133 includes a plurality of cover elements 133A divided in the circumferential direction of the casing main body 132. Each cover element 133A has a cooling jacket 134 and is formed in an arc shape along the outer surface of the housing main body 132. The casing main body 132 has a complicated shape because it has a discharge-side flow path of liquefied carbon dioxide, a motor mounting portion, and the like, but in the present embodiment, the pump cover 133 can be mounted to the casing main body 132 compactly and efficiently by using the divided cover member 133A while avoiding interference with the discharge-side flow path, the motor mounting portion, and the like. The material of the pump cover 133 is not particularly limited, and is preferably made of a material having high thermal conductivity.

In the present embodiment, the type having the impeller 131 is illustrated as the 1 st fluid pump 13, but the 1 st fluid pump 13 may include a diaphragm pump, a vane pump, a gear pump, or the like. When the 1 st fluid pump 13 includes a diaphragm pump, a diaphragm as a driving portion is attached to the housing main body 132. At this time, the pump cover 133 may be mounted on the outer surface of the case main body 132 in such a manner as to avoid the diaphragm.

Fig. 3 is a schematic cross-sectional view of tank 12 for explaining a connection method between tank 12 and 2 nd pipe 22. The tank 12 includes a tank main body 122 for storing liquefied carbon dioxide, a tank cover 123 detachably attached in close contact with the tank main body 122, and a heat insulating case 125 for integrally covering the tank main body 122 and the tank cover 123, and a cooling jacket 124 is formed on the tank cover 123. Here, the 2 nd pipe 22 is connected to the plurality of cooling jackets 124 of the tank cover 123, and thus the refrigerant supplied from the 2 nd pipe 22 to the cooling jackets 124 cools the liquefied carbon dioxide inside the tank main body 122 by the cooling jackets 124 and the tank main body 122.

In the present embodiment, the tank body 122 and the tank cover 123 are covered with the heat insulating case 125, whereby the temperature rise of the refrigerant supplied to the cooling jacket 124 can be suppressed. Such a heat insulating housing 125 may be made of a heat insulating material such as polyurethane. The material of the tank cover 123 is not particularly limited, and is preferably made of a material having high thermal conductivity.

Returning to fig. 1, the fluid supply apparatus 1 of the present embodiment includes a controller 42 that adjusts the opening degree of the flow rate adjustment valve 32 in the refrigerant pipe 31 and the amount of heat supplied to the refrigerant heater 24 based on the detection result of the temperature sensor 41 that detects the temperature of the liquefied carbon dioxide in the portion of the 1 st pipe 16 on the downstream side of the 1 st fluid pump 13 and on the upstream side of the heater 14. In this case, the controller 42 adjusts the freezing capacity of the refrigerant according to the temperature of the liquefied carbon dioxide to be supplied to the location in the heater 14. Thus, in the present embodiment, the temperature of the liquefied carbon dioxide supplied to the heater 14 can be controlled to a desired temperature in a simple manner.

In the fluid supply device 1 of the present embodiment described above, even if the temperature of the carbon dioxide cooled by the refrigerant in the heat exchanger 11 increases before it reaches the tank 12 or the 1 st fluid pump 13, the temperature increase can be suppressed by cooling by the refrigerant in the tank 12 and the 1 st fluid pump 13. This enables the temperature of the fluid (carbon dioxide) to be stably maintained at a desired temperature particularly between the fluid 1 st pump 13 and the heater 14.

In the present embodiment, the 2 nd pipe 22 circulates the refrigerant in the order of the 1 st fluid pump 13, the tank 12, and the heat exchanger 11. This can greatly ensure the refrigeration capacity of the refrigerant at a position close to the heater 14, and thus the temperature of the carbon dioxide can be easily controlled to a desired temperature desired to be supplied to the heater 14.

The 1 st fluid pump 13 includes a casing main body 132 and a pump cover 133 attached in close contact with the casing main body 132, a cooling jacket 134 is formed on the pump cover 133, and the 2 nd pipe 22 is connected to the cooling jacket 134 of the pump cover 133. This can easily suppress the increase in the temperature of the carbon dioxide due to the heat released from the drive source (in this example, the motor of the impeller 131) of the 1 st fluid pump 13, and more specifically, can easily suppress the vaporization of the liquefied carbon dioxide. In the present embodiment, the 2 nd pipe 22 is connected to the pump cover 133 attached to the housing main body 132, but the 2 nd pipe 22 may be connected to a separate cover detachably attached to the housing of the motor, and the housing of the motor may be cooled by the refrigerant.

The tank 12 includes a tank main body 122 and a tank cover 123 attached in close contact with the tank main body 122, a cooling jacket 124 is formed on the tank cover 123, and the 2 nd pipe 22 is connected to the cooling jacket 124 of the tank cover 123. This makes it possible to easily cool the carbon dioxide inside the tank 12.

< embodiment 2 >

Next, embodiment 2 will be described with reference to fig. 4. In the components of the present embodiment, the same components as those of embodiment 1 are denoted by the same reference numerals, and descriptions thereof are omitted.

As shown in fig. 4, in the present embodiment, the 2 nd pipe 22 branches into a plurality of, specifically, 3 branches downstream of the cooler 21 and downstream of the refrigerant heater 24, and the branch portions 22B1 to B3 are connected to the 1 st fluid pump 13, the tank 12, and the heat exchanger 11 separately. The branching portions 22B1 to B3 return the refrigerant flowing through the 1 st fluid pump 13, the tank 12, and the heat exchanger 11 to the upstream side of the 2 nd fluid pump 23. In other words, the 2 nd pipe 22 includes a main channel portion 22A provided with the cooler 21, the 2 nd fluid pump 23, and the refrigerant heater 24, and 3 branch portions 22B1 to B3 that branch from the downstream end portion of the main channel portion 22A and join at the upstream end portion. Other components are the same as those of embodiment 1.

Further, the flow rate control valves 26 are provided in the branch portions 22B1 to B3, respectively. This enables the flow rates of the refrigerants for cooling the 1 st fluid pump 13, the tank 12, and the heat exchanger 11 to be adjusted, and the respective cooling degrees to be adjusted. These flow regulating valves 26 are controlled by a controller 42.

According to the present embodiment, the temperatures of the first fluid pump 13, the tank 12, and the heat exchanger 11 can be easily controlled to desired temperatures individually, and therefore, the stability of temperature maintenance can be improved.

< embodiment 3 >

Next, embodiment 3 will be described with reference to fig. 5. In the components of the present embodiment, the same components as those of embodiment 1 or embodiment 2 are given the same reference numerals, and the description thereof is omitted.

As shown in fig. 5, the 2 nd pipe 22 in the present embodiment includes: a pump connection unit 22X connected to the 1 st fluid pump 13 so that the 1 st fluid pump 13 can cool the carbon dioxide by the refrigerant; and a pump bypass portion 22Y that bypasses the pump connection portion 22X and sends the refrigerant to the downstream side without flowing through the 1 st fluid pump 13. The pump connection portion 22X and the pump bypass portion 22Y are provided with flow rate adjustment valves 26 that can adjust the flow rate of the refrigerant flowing therethrough. The other configurations are the same as those of embodiment 1. Instead of the flow rate adjustment valve 26, an on-off valve that switches only on and off may be provided.

According to the present embodiment, by providing an on-off valve or a flow rate control valve in the pump connection portion 22X and/or the pump bypass portion 22Y, it is possible to control whether or not the 1 st fluid pump 13 is cooled, or the refrigerating capacity of the 1 st fluid pump 13.

< embodiment 4 >

Next, embodiment 4 will be described with reference to fig. 6. In the components of the present embodiment, the same components as those of embodiments 1 to 3 are given the same reference numerals, and the description thereof is omitted.

As shown in fig. 6, the 1 st fluid circulation device 10 according to the present embodiment can switch between: a state in which the supercritical carbon dioxide fluid is supplied from the heater 14 to the 1 st fluid supply unit 15; and a state in which the supercritical carbon dioxide fluid is discharged toward the heat exchanger 11 by the heater 14 without supplying the supercritical carbon dioxide from the heater 14 to the 1 st fluid supply unit 15. More specifically, unlike the above embodiments, the flow rate control valve 26 is provided between the heater 14 and the 1 st fluid supply portion 15 in the 1 st pipe 16. The downstream end of the 1 st fluid supply unit 15 in the 1 st pipe 16 is not connected to the heat exchanger 11. On the other hand, in the 1 st pipe 16, a branch pipe 16A extends from between the flow rate control valve 26 and the heater 14, the flow rate control valve 26 is also provided in the branch pipe 16A, and the downstream end of the branch pipe 16A is connected to the heat exchanger 11. With this configuration, the switching can be performed by appropriately opening and closing the two flow rate control valves 26. The same effects as those of embodiment 1 can be obtained by this embodiment.

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described above. The above embodiments may be variously omitted, replaced, or modified without departing from the gist of the present invention.

In each of the above embodiments, for example, the 2 nd pipe 22 through which the refrigerant flows is connected to the 1 st fluid pump 13, the tank 12, and the heat exchanger 11, but the 2 nd pipe 22 may be connected to only one of the 1 st fluid pump 13 and the tank 12, and the heat exchanger 11. The positions of the 2 nd fluid pump 23 and the refrigerant heater 24 in the 2 nd pipe 22 are not limited to those of the above embodiments. For example, the 2 nd fluid pump 23 may be provided downstream of the cooler 21.

Further, although the description has been made above, the 1 st fluid pump 13 described in embodiment 1 may be a diaphragm pump, and a sectional view of the 1 st fluid pump 13 according to such a modification is shown in fig. 7. In this case, the diaphragm 136 is attached to the housing main body 132, and the carbon dioxide fluid flows through the housing main body 132 by pushing and pulling the diaphragm 136 by the plunger 137. In this modification, the pump cover 133 is detachably attached to the housing main body 132 so as to avoid the diaphragm 136. As shown by arrows in the figure, the refrigerant flowing from the upstream portion of the 2 nd pipe 22 through the cooling jacket 134 and flowing out to the downstream portion of the 2 nd pipe 22 flows in the direction opposite to the flow direction of the carbon dioxide.