JP2010196909A - Cryogenic cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cryogenic cooling device shortening precooling time, reducing reduction of a cold storage amount or change of a coil temperature due to temperature change of gas, and capable of carrying out simplification of a configuration. <P>SOLUTION: A cooling reception object 1 is installed in a sealed container of an airtight structure. The cryogenic cooling device includes a low temperature gas container 2 holding low temperature pressure gas in the sealed container, a low temperature buffer 5 receiving supply of the pressure gas via cooling gas piping thermally contacting the cooling reception object from the low temperature gas container, a flow control 4 valve provided in the cooling gas piping and opening and closing a conduit, a compressor 9 pressurizing the gas held in the low temperature buffer to the atmospheric pressure or more, and a measuring means for measuring a change of state of the cooling reception object. In the low temperature gas container 2, a high pressure piping connection port A for connecting high pressure piping and a coil cooling piping connection port B for connecting coil cooling piping are formed on different faces of the gas container, and in the low temperature buffer, a low pressure gas piping port C for connecting low pressure gas piping and a coil cooling piping connection port D for connecting the coil cooling piping are formed on different faces of the low temperature buffer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cryogenic cooling device applied to, for example, a single crystal pulling device, a magnetic separation device, and the like.

  In recent years, a high-temperature superconducting coil using a superconducting material having a high critical temperature has been developed, and various superconducting magnets using the high-temperature superconducting coil have been proposed. The superconducting magnet is used after being cooled to a very low temperature. For this cooling method, a method of immersion cooling with liquid helium and a method of conductive cooling with a refrigerator are employed.

  In general, the liquid helium immersion method is applied to a device that generates a large amount of heat and a device that requires stability (see, for example, Non-Patent Document 1), and the conduction cooling method is a small superconducting device and a small heat load. Applied to superconducting magnets.

  Since the high-temperature superconducting coil can be used at a higher temperature than the conventional metal-based superconducting coil, a cooling method different from the conventional one can be considered. In particular, for cooling a superconducting coil that generates a large amount of heat temporarily, such as a superconducting energy storage device (SMES), an immersion cooling method using liquid helium, which can be expected to have a large cooling capacity due to latent heat of vaporization, has been adopted. However, since the cooling temperature is limited to 4K in the immersion cooling method using liquid helium, it cannot be a cooling method suitable for the high-temperature superconducting coil.

  On the other hand, the present inventors have developed a cryogenic cooling device to which a gas regenerative cooling system having a large cooling capacity is applied even at a high cooling temperature at which a high-temperature superconducting magnet can be used.

  FIG. 8 is a side view showing, as a partial cross-section, a conventional cryogenic cooling device 100 to which this gas regenerative cooling system is applied. As shown in FIG. 8, this cryogenic cooling device 100 includes an airtight sealed box-shaped vacuum heat insulating container 101 as a closed container, and a cooling gas is provided on one side wall side (the right side in the drawing) in the vacuum heat insulating container 101. The pipe 102 is arranged vertically. A cryogenic refrigerator 101a is provided at the upper end of the cooling gas pipe 102, and a cryogenic gas container 103 for accommodating a cryogenic gas (for example, helium gas) is provided at the lower end side.

  A low-temperature buffer 104 is disposed at a lower end position (on the left side in the drawing) facing the low-temperature gas container 103 in the vacuum heat insulating container 101, and these vacuum heat insulating container 101 and the low-temperature buffer 104 are connected by a coil cooling gas pipe 105. Thus, the cooling gas flows into the coil cooling gas pipe 105 from the low temperature gas container 103 side.

  In addition, a superconducting coil 106 that is a device to be cooled is disposed in the central portion of the coil cooling gas pipe 105 in the length direction. The coil cooling gas pipe 105 has an arcuate portion 105 a having the same axis as the superconducting coil 106. Is formed. The arc-shaped portion 105 a of the coil cooling gas pipe 105 is disposed at a substantially central portion in the radial direction of the superconducting coil 106. The coil cooling gas pipe 105 is provided with a cooling gas flow rate control valve 107. The superconducting coil 106 is provided with a temperature detector (thermometer) 108.

  A high-temperature gas pipe 109 is connected to the low-temperature buffer 104, and this high-temperature gas pipe 109 is connected to a cryogenic compressor 111 via a compressor flow rate adjustment valve 110 above the vacuum heat insulating container 101. The high temperature gas pipe 109 is provided with heat exchangers 112a and 112b. A high pressure pipe 113 is connected to the discharge side of the cryogenic compressor 111, and a compressor flow rate adjustment valve 114 is provided in the high pressure pipe 113.

  Further, the high-pressure pipe 113 is connected to the refrigerator heat exchangers 115 a and 115 b of the cooling gas pipe 102 through the heat exchangers 112 a and 112 b in the vacuum heat insulating container 101. The refrigerator heat exchangers 115a and 115b are provided with a precooling pipe 116, and the precooling pipe 116 is provided with a precooling valve 117. Superconducting coil 106 is connected to cooling gas pipe 102 via heat transfer member 118.

  With this configuration, pressurized helium gas cooled to a low temperature is stored in the low temperature gas container 103, and the superconducting coil 106 is cooled by flowing the gas through the coil cooling gas pipe 105 at a differential pressure with the low temperature buffer 104 as necessary. Is done. The helium gas that has moved from the cryogenic gas container 103 to the cryogenic buffer 104 is compressed again by the cryogenic compressor 111, cooled by the cryogenic refrigerator 111 and the heat exchangers 112 a and 112 b, and returned to the cryogenic gas container 103. Ready for the next cooling.

Cryogenic engineering Vol. 37 (2002) p18-26

  Incidentally, the above-described cooling system shown in FIG. 8 has the following problems (1) to (4).

(1) Problems concerning the method of pre-cooling the low temperature gas container In the configuration of FIG. 8, when the superconducting coil 106 is cooled from room temperature, the superconducting coil 106 is gas-cooled by continuously flowing a cooling gas. And the cryogenic refrigerator 101a reduce the temperature difference, thereby efficiently cooling and shortening the cooling time. However, in this configuration, since the coil cooling gas pipe 105 is provided only on the upper surface side of the low temperature gas container 103 and the low temperature buffer 104, gas cooling cannot always be performed efficiently, and the cooling time of the entire apparatus can be shortened. There is a problem that it cannot be planned.

  In addition, since the pipes 105 and 109 connected to the low temperature gas container 103 and the low temperature buffer 104 are collectively arranged at one location above the low temperature gas container 103, precooling with the low temperature gas can always be performed efficiently. However, a certain amount of time was required for precooling.

(2) Problems concerning expansion and compression of gas In the conventional cooling method, the temperature of the helium gas changes when the gas is pressurized and depressurized. This change in temperature may adversely affect the gas flow.

  The first effect is that when the gas flows from the low temperature gas container 103 to the low temperature buffer 104, the gas temperature in the low temperature gas container 103 decreases due to a decrease in the pressure of the low temperature gas container 103, while the pressure of the low temperature buffer 104 This is a case where the gas temperature in the low temperature buffer 104 rises due to the increase in the gas pressure.

  In this case, the gas density of the low temperature gas container 103 is increased, and the amount of gas remaining in the low temperature gas container 103 is increased as compared with the case where the temperature does not change. The amount of gas that can be filled in 104 is reduced as compared with the case where there is no temperature change. As a result, the amount of gas that can be sent from the low temperature gas container 103 to the low temperature buffer 104 is reduced as compared with the case where the temperature does not change. In this way, since the amount of gas that can be used decreases, the amount of cold storage decreases, and the amount of heat that can be removed decreases.

  The second effect is when the gas in the low temperature buffer 104 is pressurized and filled into the low temperature gas container 103. Also in this case, the temperature in the low temperature gas container 103 is increased and the gas density is decreased, and the temperature is decreased in the low temperature buffer 104 and the gas density is increased. Decrease. This also leads to a decrease in the amount of cold storage, and the amount of heat removal decreases.

(3) Problem of influence on coil due to change in gas temperature Conventionally, a gas cooled to a low temperature is filled in the cryogenic gas container 103. In this case, the gas is stored in the cryogenic gas container 103 at the time of gas filling. In order to compress the gas, there was a problem that the gas temperature increased. That is, when the temperature of the cryogenic gas container 103 rises during gas filling, the temperature of the cryogenic refrigerator 111 rises and the temperature of the superconducting coil 106 rises.

(4) Problems with the double cooling system The cooling system shown in FIG. 8 is usually cooled by conduction cooling and gas cooling only when there is temporary heat generation. Yes. For this reason, the structure is complicated.

  The present invention has been made to solve such problems, and shortens the pre-cooling time, reduces the amount of cold storage and changes in coil temperature due to changes in gas temperature, and simplifies the configuration. An object of the present invention is to provide a cryogenic cooling device capable of achieving the above.

  In order to achieve the above object, in the present invention, an object to be cooled that is a cryogenic cooling object is installed in an airtight sealed container, and a low-temperature gas container that contains a low-temperature pressurized gas is contained in the airtight container. A low-temperature buffer that receives the pressurized gas from the low-temperature gas container via a cooling gas pipe that is in thermal contact with the object to be cooled from the low-temperature gas container, and is provided in the cooling gas pipe A cooling gas flow rate control valve that opens and closes the pipeline, and the supply of the gas stored in the low-temperature buffer is received by a low-pressure pipe, the gas is pressurized to atmospheric pressure or higher, and the high-pressure gas is supplied to the low-temperature gas container via the high-pressure pipe. And a measuring means for measuring a state change of the object to be cooled, wherein the low temperature gas container has a high pressure pipe connection port for connecting the high pressure pipe and a coil cooling port for connecting the coil cooling pipe. While the pipe connection port is formed on a different surface of the gas container, the low temperature buffer includes the low pressure gas pipe port connecting the low pressure gas pipe and the coil cooling pipe connection port connecting the coil cooling pipe. The cryogenic cooling device is characterized by being formed on different surfaces.

  According to the present invention, the gas can be efficiently flowed by forming the pipe connection ports on the different surfaces of the low temperature gas container and the low temperature buffer, the precooling time can be shortened, and the temperature change of the gas A decrease in the amount of cold storage and a change in coil temperature can be reduced, and the configuration can be simplified.

The schematic diagram which shows the cryogenic cooling device by 1st Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 2nd Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 3rd Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 4th Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 5th Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 6th Embodiment of this invention. The schematic diagram which shows the cryogenic cooling device by 7th Embodiment of this invention. The schematic diagram which shows a prior art example.

  Hereinafter, embodiments of a cryogenic cooling device according to the present invention will be described with reference to the drawings.

First Embodiment (FIG. 1)
FIG. 1 is a schematic diagram showing a cryogenic cooling device 100A according to a first embodiment of the present invention.

  As shown in FIG. 1, the cryogenic cooling device 100A of the present embodiment includes a sealed container 20 made of a vacuum heat insulating container having an airtight structure, and one side (lower right side in the figure) in the sealed container 20 is provided. A low temperature gas container 2 is disposed, and the low temperature gas container 2 contains a low temperature pressurized gas.

  In the sealed container 20, a superconducting coil 1 that is an object to be cooled that is a target for cryogenic cooling is installed. Further, a low-temperature buffer 5 is provided on the other side (the left side in the figure) in the hermetic container 20, and the cooling gas (arrow a1) is supplied from the low-temperature gas container 2 side via the coil cooling gas pipe 3 which is a coil cooling pipe. It is configured to receive. The coil cooling gas pipe 3 is provided with a cooling gas flow rate control valve 4 for opening and closing the pipe line.

  Moreover, the gas accommodated in the low temperature buffer 5 is supplied to the compressor 9 via the low pressure gas pipe 10a, and is pressurized to the atmospheric pressure or higher. Then, the high pressure gas is supplied to the low temperature gas container 2 through the high pressure gas pipe 10b. In addition, a thermometer 7 is provided as a temperature measuring means for measuring the state change of the superconducting coil 1 that is an object to be cooled.

  Further, a high pressure pipe connection port “A” for connecting the high pressure gas pipe 10 b is formed on the upper surface side of the low temperature gas container 2, while a coil cooling gas pipe 3 is connected to the lower surface side of the low temperature gas container 2. A coil cooling gas pipe connection port “B” is formed. Thus, in this embodiment, the high-pressure pipe connection port “A” and the coil cooling gas pipe connection port “B” are formed on different surfaces of the gas container.

  The low temperature buffer 5 has a coil cooling gas pipe connection port “C” for connecting the coil cooling gas pipe 3 and a low pressure gas pipe connection port “D” for connecting the low pressure gas pipe 2 on different surfaces of the low temperature buffer 5. Is formed. That is, a superconducting coil 1 that is an object to be cooled, a low-temperature gas container 2 that can store pressurized gas, and a coil cooling gas that is connected to the low-temperature gas container 2 and is in thermal contact with the object to be cooled A pipe 3 is provided.

  Further, a heat transfer member 8 for cooling the coil 1 with the cryogenic refrigerator 6, a compressor 9 for compressing the gas accommodated in the low temperature buffer 5 and refilling the low temperature gas container 2, and a low pressure gas pipe 10a. And a high-pressure gas pipe 10b. Furthermore, the heat for the heat exchange of the gas reciprocating between the low-temperature part and the room-temperature part in the compression process by the compressor 9 with the refrigerator heat exchangers 11a and 11b for cooling the compressed gas with the cryogenic refrigerator 6 Exchangers 12a and 12b and compressor flow rate adjusting valves 13a and 13b provided at the entrance and exit of the compressor 9 are provided.

  A precooling pipe 14 bypassing the two-stage heat exchanger 12b branched from the high-pressure gas pipe 10b, a precooling valve 15 provided in the precooling pipe 14, and a vacuum heat insulating container 20 containing these low-temperature portions are provided. It is. Further, a heat transfer member 8 is connected to the superconducting coil 6, and the coil cooling gas pipe 3 is connected to the low temperature gas container 2 by a metal heat transfer member 8 arranged in an inclined manner.

  In the cryogenic cooling device 100A configured as described above, the superconducting coil 1 is cooled by the cryogenic refrigerator 6 via the heat transfer member 8 at the normal time. When a large amount of heat is generated due to a current change or the like and the temperature of the superconducting coil 1 rises, the cooling gas flow rate control valve 4 is opened and cooled by the cryogenic refrigerator 6 and stored in the cryogenic gas container 2. The gas becomes a pressurized gas at atmospheric pressure or higher.

  Then, as indicated by an arrow a1, the superconducting coil 1 is rapidly cooled by flowing a large amount of low-temperature gas through the coil cooling gas pipe 3 at once. The gas after cooling the superconducting coil 1 is temporarily stored in the low temperature buffer 5, passes through the low pressure gas pipe 10a, is compressed by the compressor 9, and then is filled into the low temperature gas container 2 through the high pressure gas pipe 10b. .

  At this time, the compressed gas is cooled by the two heat exchangers 12a and 12b and the refrigerator heat exchangers 11a and 11b. The gas flow rate in this case is set to a much smaller flow rate than the flow rate when cooling the superconducting coil 1 in order to reduce the thermal load on the refrigerator 6.

  As a result, the superconducting coil 1 can be rapidly cooled with a refrigerating capacity that is extremely larger than the refrigerating capacity of the refrigerator 6.

  When the cryogenic cooling device 100A is cooled from room temperature to a predetermined temperature, the cooling gas flow rate control valve 4 and the precooling valve 15 are opened, and the compressor flow rate control valves 13a and 13b are used to flow at the same level as the gas filling process. In a state where the gas is compressed, the superconducting coil 1 is cooled by cooling the gas compressed by the compressor 9 with the refrigerator heat exchangers 11 a and 11 b and flowing it through the coil cooling gas pipe 3. As a result, the superconducting coil 1 can be cooled in a shorter time than when the superconducting coil 1 is cooled by the heat transfer member 8.

  In addition, by providing the pre-cooling pipe 14 and the pre-cooling valve 15, the gas cooled by the first-stage refrigerator heat exchanger 11a is warmed to the gas flowing through the low-pressure gas pipe 10a by the two-stage heat exchangers 12a and 12b. To prevent it from getting worse.

  Further, in the configuration shown in FIG. 1, the connection part A of the high temperature gas pipe 10 b entering the low temperature gas container 2 and the connection part B of the coil cooling gas pipe 3 exiting from the low temperature gas container 2 are substantially the same as the low temperature gas container 2. Since it is attached to the opposite position (vertical position) on the opposite side, the cryogenic gas container 2 is also cooled in a short time.

  Similarly, since the connecting portions C and D of the low pressure gas pipe 10a and the coil cooling gas pipe 3 entering and exiting the low temperature buffer 5 are also attached to substantially the corresponding positions (up and down positions) on the opposite side, the low temperature buffer 5 can be used for a short time. It becomes possible to cool with. Conventionally, since the pipes that go in and out of the low temperature gas container 2 were installed together in one place, it was not possible to precool with the low temperature gas and required a certain amount of time during the precooling, Since the low-temperature gas container 2 and the low-temperature buffer 5 can be pre-cooled with the low-temperature gas, the pre-cooling time can be shortened as compared with the conventional case.

  That is, according to this embodiment, the connection port “A” for connecting the high-pressure pipe 10 b to the low-temperature gas container 2 and the connection port “B” for connecting the coil cooling gas pipe 3 that is the coil cooling pipe are individually provided. The connection port “C” for connecting the coil cooling gas pipe 3 to the low-temperature buffer 5 and the connection port “D” for connecting the low-pressure gas pipe 10a are separately provided, so that the high temperature entering the low-temperature gas container 2 can be obtained. Since the connection part of the gas pipe 10b and the connection part of the coil cooling gas pipe 3 coming out of the low temperature gas container 2 are mounted on the substantially opposite side of the low temperature gas container 2, the low temperature gas container 2 is also cooled in a short time.

[Second Embodiment] (FIG. 2)
FIG. 2 is a schematic diagram showing a cryogenic cooling device 100B according to a second embodiment of the present invention. In the following embodiments, the same parts as those in the first embodiment are denoted by the same reference numerals, and description of the structure of the parts is omitted.

  In 2nd Embodiment of this invention, as shown in FIG. 2, the copper block 16 with the fin 16a is inserted in the inside of the cryogenic gas container 2. As shown in FIG. Thereby, the gas inside the cryogenic gas container 2 is cooled by direct contact with the fins 16a.

  That is, in this embodiment, since the cryogenic refrigerator 6 directly cools the gas in the cryogenic gas container 2, the gas in the cryogenic gas container 2 can be sufficiently cooled. As a result, not only can the temperature of the low-temperature gas when cooling the superconducting coil 1 be sufficiently low, but the density of the gas can be increased, so that the amount of gas that can be filled in the low-temperature gas container 2 can be increased.

  However, in this embodiment, if the gas flow rate at the time of filling is large, the temperature of the cryogenic gas container 2 increases, the cooling stage temperature of the refrigerator increases, and the temperature of the superconducting coil 1 may increase. Therefore, in this embodiment, a thermometer 7b for measuring the temperature of the low temperature gas container 2 is attached, and the compressor flow control valve 13b is adjusted so that the temperature does not rise. Thereby, the temperature rise of the superconducting coil 1 can be prevented at the time of gas filling. Other configurations are substantially the same as those in the first embodiment.

  According to the present embodiment, compared to the case where the gas cooled to a low temperature is filled in the low temperature gas container 2, the gas temperature rise for compressing the gas in the low temperature gas container 2 at the time of gas filling is prevented. can do.

[Third Embodiment] (FIG. 3)
FIG. 3 is a schematic diagram showing a cryogenic cooling device 100c according to a third embodiment of the present invention.

  In this embodiment, as shown in FIG. 3, the cryogenic gas container 2 is configured as a coiled cryogenic gas storage pipe 2b made of a large diameter pipe. The low temperature gas storage pipe 2b is wound around the copper block 16b. Other configurations are substantially the same as those in the first embodiment.

  According to the present embodiment, the cryogenic refrigerator 6 can sufficiently cool the gas in the low temperature gas storage pipe 2b, so that the temperature of the gas when cooling the superconducting coil 1 can be sufficiently lowered. . Moreover, according to this configuration, as a result of the density of the low temperature gas being increased, the amount of gas that can be filled in the low temperature gas container 2 can be increased. Other configurations are substantially the same as those in the first embodiment.

[Fourth Embodiment] (FIG. 4)
FIG. 4 is a schematic diagram showing a cryogenic cooling device 100d according to a fourth embodiment of the present invention.

  In the present embodiment, as shown in FIG. 4, the low temperature gas container 2 and the low temperature buffer 5 are thermally connected by a heat transfer member 17. Thereby, heat flows from the low temperature buffer 5 whose temperature has increased to the low temperature gas container 2 whose temperature has decreased, and the temperature change between the low temperature gas container 2 and the low temperature buffer 5 becomes small.

  As a result, the amount of gas that can flow from the low temperature gas container 2 to the low temperature buffer 5 increases, and the refrigeration capacity can be increased.

  That is, conventionally, when gas flows from the low temperature gas container 2 to the low temperature buffer 5, the temperature of the low temperature gas container 2 decreases as the pressure decreases, and conversely, the temperature of the low temperature buffer 5 increases as the pressure increases. . For this reason, the pressure in the low temperature gas container 2 decreases more than the decrease due to the outflowing gas, and conversely, the pressure in the low temperature buffer 5 increases above the increase in pressure due to the inflowing gas.

  As a result, the pressure difference between the cryogenic gas container 2 and the cryogenic buffer 5 is smaller than when there is no temperature change, and the amount of gas that can be supplied is reduced.

  On the other hand, according to the present embodiment, the amount of gas that can flow from the low temperature gas container 2 to the low temperature buffer 5 increases, and the refrigerating capacity can be increased. Other configurations are substantially the same as those in the first embodiment. Moreover, although the example connected with the heat-transfer member 17 was shown in this Embodiment, it is also possible to connect directly thermally.

[Fifth Embodiment] (FIG. 5)
FIG. 5 is a schematic diagram showing a cryogenic cooling device 100E according to a fifth embodiment of the present invention.

  In this embodiment, the heat transfer member 18 that connects the low-temperature buffer 5 and the cryogenic refrigerator 6 and the heater 19 that heats the low-temperature gas container 2 are provided. Thereby, even if the temperature of the low temperature buffer 5 rises, the temperature change can be reduced by cooling with the refrigerator 6 and the pressure rise can be suppressed. On the other hand, when the temperature in the low temperature gas container 2 falls below the set value, the temperature change of the low temperature gas container 2 can be reduced by heating with the heater 19, and the pressure drop can be suppressed small. As a result, the amount of gas that can flow from the low temperature gas container 2 to the low temperature buffer 5 increases, and the refrigeration capacity can be increased.

[Sixth Embodiment] (FIG. 6)
FIG. 6 is a schematic diagram showing a cryogenic cooling device 100F according to a sixth embodiment of the present invention.

  In the cryogenic cooling device 100F of the present embodiment, as shown in FIG. 6, the compressor 9 that compresses the gas in the cryogenic buffer 5 and fills the cryogenic gas container 2, and the cryogenic buffer 5 and the compressor 9 are connected. A low-pressure pipe 10a, a high-pressure pipe 10b connecting the compressor 9 and the low-temperature gas container 2, and heat exchangers 12a and 12b for exchanging heat through the gas flowing through the low-pressure pipe 10a and the high-pressure pipe 10b. The buffer 10c is provided inside or behind the heat exchangers 12a and 12b.

  That is, the low temperature gas container 2 and the low temperature buffer 5 are thermally connected directly or via the heat transfer member 17.

  In the present embodiment, a part of the high-pressure gas pipe 10b of the two-stage heat exchangers 12a and 12b is thickened to form the buffer 10c.

  When the gas in the low temperature gas container 2 is flowed, the gas having a high temperature in the buffer 10c, which is a part of the high pressure gas pipe 10b, flows into the low temperature gas container 2, and the temperature change of the low temperature gas container 2 becomes small, and the pressure change becomes small. Can be suppressed. Other configurations are substantially the same as those of the first embodiment.

[Seventh Embodiment] (FIG. 7)
FIG. 7 is a schematic diagram showing a cryogenic cooling device 100G according to a seventh embodiment of the present invention.

  In the cryogenic cooling device 100G of the present embodiment, as shown in FIG. 7, the same cooling gas as that of the above embodiments is applied to the coil cooling gas pipe 3 provided between the cryogenic gas container 2 and the superconducting coil 1. A bypass pipe 3a is provided in parallel with the flow rate control valve 4, and a flow rate adjustment valve 4b is provided in the bypass pipe 3a. The added flow regulating valve 4b is a small flow regulating valve. Further, the low-temperature gas container 2 is provided with a heater 19 and a thermometer 7b so that the low-temperature gas container 2 can be heated to a predetermined temperature.

  During steady operation of the cryogenic cooling device 100G, the cooling gas flow rate control valve 4 is closed, the small flow rate flow rate adjusting valve 4b is opened, and the low temperature gas container 2 is connected to the coil cooling gas pipe 3 via the flow rate adjusting valve 4b. A small flow rate of gas is flowed, thereby cooling the superconducting coil 1.

  On the other hand, when there is a large heat generation due to a current change or the like and the temperature of the superconducting coil 1 rises, the cooling gas flow rate control valve 4 is also opened and a large amount of gas is flowed to rapidly cool the superconducting coil 1. Do.

  According to the present embodiment, the provision of the flow rate adjusting valve 4b eliminates the need for the coil heat transfer member 8 provided in the other embodiments, which is necessary for cooling during normal operation.

  Further, since the superconducting coil 1 is cooled only from the coil cooling gas pipe 3, the heat transfer path becomes constant, so that there is an advantage that the cooling design becomes easy. Other configurations are the same as those in the above-described embodiments, and a description thereof will be omitted.

DESCRIPTION OF SYMBOLS 1 ... Superconducting coil 1a-1g ... Cryogenic cooling device 2 ... Cryogenic gas container 3 ... Coil cooling gas piping 4 ... Cooling gas flow control valve 5 ... Cryogenic buffer 6 ... Cryogenic refrigerator 7 ... Thermometer (measuring means)
8 Heat transfer member 9 Compressor 10a Low pressure gas pipe 10b High pressure gas pipe 11a, 11b Refrigerator heat exchangers 12a, 12b Heat exchangers 13a, 13b Compressor flow rate adjustment valve 14 Precooling pipe 15 Pre-cooling valve 16 ... Copper block 16a ... Fin 17 ... Heat transfer member 18 ... Heat transfer member 19 ... Heater 20 ... Sealed container (vacuum insulation container)
100A to 100F, cryogenic cooling device 101, vacuum heat insulating container 101a, cryogenic refrigerator 102, cooling gas pipe 103, low temperature gas container 104, low temperature buffer 105, coil cooling gas pipe 105a, arc-shaped portion 106, superconducting coil 107 Cooling gas flow control valve 108 Temperature detector 109 Hot gas piping 110 Compressor flow adjustment valve 111 Cryogenic compressors 112a and 112b Heat exchanger 113 High pressure piping 114 Compressed air flow adjustment valves 115a and 115b ... Refrigerator heat exchanger 116 ... Pre-cooling pipe 117 ... Pre-cooling valve 118 ... Superconducting member "A" ... High-pressure piping connection port "B" ... Coil cooling piping connection port "C" ... Low-pressure gas piping port "D" ... Coil cooling piping Connection

Claims (10)

An object to be cooled that is subject to cryogenic cooling is installed in an airtight sealed container, and a cryogenic gas container that contains a low-temperature pressurized gas is disposed in the sealed container, and the object to be cooled is disposed from the cryogenic gas container. A low-temperature buffer that receives supply of the pressurized gas from the low-temperature gas container through a cooling gas pipe that is in thermal contact with the cooling gas pipe, a cooling gas flow rate control valve that is provided in the cooling gas pipe and opens and closes the pipe line, A compressor for supplying the gas stored in the low-temperature buffer by a low-pressure gas pipe, pressurizing the gas to an atmospheric pressure or higher, and supplying the high-pressure gas to the low-temperature gas container via the high-pressure pipe; Measuring means for measuring the state change of the gas, the low temperature gas container comprises a high pressure pipe connection port for connecting the high pressure pipe and a coil cooling gas pipe connection port for connecting the coil cooling gas pipe. On the other hand, the low temperature buffer has a low pressure gas piping port connecting the low pressure gas piping and a coil cooling gas piping connection port connecting the coil cooling gas piping formed on different surfaces of the low temperature buffer. A cryogenic cooling device characterized by that. 2. The cryogenic cooling device according to claim 1, wherein the high-pressure pipe connection port and the coil cooling gas pipe connection port, and the low-pressure gas pipe connection port and the coil cooling gas pipe port are attached at opposing positions. The cryogenic cooling device according to claim 1 or 2, wherein any one of the cryogenic gas container, the cryogenic refrigerator, and the cryogenic buffer is thermally connected directly or via a heat transfer member. The cryogenic cooling device according to claim 3, wherein the heat transfer member penetrates the wall of the cryogenic gas container and protrudes into the container. A means for controlling a flow rate when the cryogenic gas container is filled with a gas pressurized to an atmospheric pressure or higher, and a means for measuring the temperature of the cryogenic gas container, the temperature of the cryogenic gas container being equal to or higher than a predetermined temperature The cryogenic cooling device according to claim 3 or 4, wherein the gas flow rate is controlled so as not to rise. The cryogenic temperature according to any one of claims 1 to 3, wherein the cryogenic gas container has a configuration in which a pipe is wound, and is cooled by being wound around a heat transfer member attached to the cryogenic refrigerator. Cooling system. The cryogenic cooling device according to any one of claims 1 to 6, wherein the cryogenic gas container is provided with heating means for heating the inside of the cryogenic gas container when the temperature in the cryogenic gas container falls below a set value. A compressor that compresses the gas in the low-temperature buffer and fills the low-temperature gas container; a low-pressure gas pipe that connects the low-temperature buffer and the compressor; and a high-pressure gas that connects the compressor and the low-temperature gas container A pipe and a heat exchanger that exchanges heat between the gas flowing through the low-pressure gas pipe and the high-pressure gas pipe, and a buffer is provided in the heat exchanger or in front and rear portions of the heat exchanger. The cryogenic cooling device according to any one of 6. The cryogenic cooling device according to claim 8, comprising a two-stage heat exchanger arranged in series as the heat exchanger, wherein a part of a low temperature side pipe constituting a flow path of these heat exchangers has a large diameter as a buffer. . 10. The system according to claim 1, wherein a flow rate adjustment valve is provided in parallel with the cooling gas flow rate control valve, and cooling is performed by flowing a gas through a cooling gas pipe via the flow rate adjustment valve in a steady state. Cryogenic cooling system.

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