JP3676407B2 - Refrigerant supply device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a refrigerant supply device that feeds a refrigerant such as liquid nitrogen and cools a portion to be cooled and then returns the refrigerant. The present invention can be applied to, for example, a cryogenic apparatus that cools a shield plate that covers a container with a refrigerant such as liquid nitrogen in order to maintain the cryogenic temperature of the container in which liquid helium containing a superconducting magnet is loaded.
[0002]
[Prior art]
As a prior art, “a cooling device for a radiation shield plate for cryostat” disclosed in Japanese Patent Publication No. 3-17057 is known. This includes a liquid helium tank for cooling the superconducting magnet, a shield plate for covering and maintaining the liquid helium tank at a low temperature, a conduit in thermal contact with the shield plate, and for supplying liquid nitrogen to the conduit. And an impeller pump. In this impeller pump, the main impeller must be constantly rotated in order to convert the kinetic energy of the rotation of the main impeller into a pressure head that is a supply source of liquid nitrogen.
[0003]
[Problems to be solved by the invention]
However, since a low-temperature liquid refrigerant such as liquid nitrogen lacks lubricity, there is a problem that the bearing supporting the main impeller is easily worn and the life of the impeller pump is short. Further, the frictional heat generation in the bearing supporting the main impeller is large, and there is a problem that the low-temperature liquid refrigerant easily evaporates due to the frictional heat generation and the cooling efficiency is lowered.
[0004]
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to eliminate the impeller-type pump when returning the refrigerant to the main chamber, and when returning by supplying a low-temperature liquid refrigerant such as liquid nitrogen. It is an object of the present invention to provide a refrigerant supply device that is advantageous in improving the cooling efficiency by improving problems such as bearing wear and frictional heat generation of the bearing.
[0005]
[Means for solving the problems]
  The refrigerant supply device according to claim 1, wherein a main chamber in which a liquid refrigerant is stored and a gaseous refrigerant is stored on a liquid surface of the liquid refrigerant;
  A sub-chamber in which the liquid refrigerant is stored and the gaseous refrigerant is stored on the liquid surface of the liquid refrigerant;
  A refrigerant return passage that connects the main chamber and the sub chamber and includes a cooled portion in the middle, and cools the cooled portion with the liquid refrigerant fed from the sub chamber, and then returns the refrigerant to the main chamber;
  A supply passage for supplying liquid refrigerant in the main chamber to the sub chamber;
  A restricting means for restricting a flow rate of the refrigerant disposed in the supply passage and flowing through the supply passage;
  The refrigerant in the subchamber is heated, and the liquid refrigerant in the subchamber is supplied to the refrigerant return passage by the gas pressure of the gaseous refrigerant in the subchamber that is increased as a result of heating, and the refrigerant is supplied to the main chamber via the refrigerant return passage. Heat source means to return,
  Pressure adjusting means capable of adjusting at least one of the gas pressure of the gaseous refrigerant in the main chamber and the gas pressure of the gaseous refrigerant in the sub chamber with respect to the other;And
The pressure adjusting means includes a pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the sub chamber is stored, and an on-off valve that opens and closes the pressure equalizing passage. HaveIt is characterized by this.
[0006]
Any heat source means may be used as long as it can heat the liquid refrigerant in the sub chamber. For example, an electric heater method, a heat transfer means for transferring heat outside the apparatus (external temperature, etc.), a gas heating method, a solar heating method, etc. Can be adopted.
According to a second aspect of the present invention, there is provided the refrigerant supply device according to the first aspect, wherein the restricting means is any one of an on-off valve, a one-way valve, and an orifice disposed in the supply passage.
[0007]
  A refrigerant supply device according to a third aspect is the one according to the first or second aspect.ColdA backflow prevention valve for blocking the flow of the refrigerant from the medium return passage to the sub chamber is provided in at least one of the refrigerant return passage and the sub chamber. Therefore, even when the refrigerant return passage becomes excessively high for some reason, it is possible to prevent the refrigerant in the refrigerant return passage from flowing back into the sub chamber. Therefore, it is advantageous to obtain a pump action by a heat source.
[0008]
  Claim4The refrigerant supply device ofIn each claimThe small chamber having a smaller volume than the sub chamber is provided in communication with the sub chamber, and the heat source means heats the refrigerant in the small chamber.
  Claim5The refrigerant supply device ofIn each claimThe sub chamber is equipped with a float that floats on the liquid refrigerant in the sub chamber. The float includes a small chamber into which a part of the liquid refrigerant in the sub chamber enters, and the heat source means heats the refrigerant in the small chamber. It is characterized by that.
  Claim6The refrigerant supply device includes a main chamber in which a liquid refrigerant is stored and a gaseous refrigerant is stored on a liquid surface of the liquid refrigerant;
  A sub-chamber having a first sub-chamber and a second sub-chamber, wherein the liquid refrigerant is housed and a gaseous refrigerant is housed on a liquid surface of the liquid refrigerant;
  A main passage provided between the main chamber and the first sub-chamber and provided with a cooled portion in the middle; a sub-passage connecting the upstream side of the cooled portion and the second sub-chamber; A refrigerant return passage for returning the refrigerant to the main chamber after cooling the cooled portion with the liquid refrigerant fed from the chamber, a first supply passage for supplying the liquid refrigerant in the main chamber to the first sub chamber, A supply passage having a second supply passage for supplying the liquid refrigerant to the second sub chamber;
  A regulating means for regulating the flow rate of the refrigerant flowing through the supply passage, and having a first restriction means disposed in the first supply passage and a second restriction means disposed in the second supply passage;
  Heat source means having first heat source means for heating the refrigerant in the first subchamber and second heat source means for heating the refrigerant in the second subchamber;
  A first pressure adjusting means capable of adjusting at least one of a gas pressure of the gaseous refrigerant in the main chamber and a gas pressure of the gaseous refrigerant in the first sub chamber with respect to the other; a gas pressure of the gaseous refrigerant in the main chamber; Pressure adjusting means having second pressure adjusting means capable of adjusting at least one of the gas pressure of the gaseous refrigerant in the second sub chamber with respect to the other;
  The 1st backflow prevention valve which blocks | prevents the flow of the refrigerant | coolant from the main path of a refrigerant | coolant return path to a 1st subchamber, and the 2nd backflow prevention valve which blocks | prevents the flow of the refrigerant | coolant from the subpath of a refrigerant | coolant return path to a 2nd subchamber And a backflow prevention valve havingAnd
The first pressure adjusting means opens and closes a first pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the first sub chamber is stored, and the first pressure equalizing passage. A first on-off valve;
The second pressure adjusting means opens and closes the second pressure equalizing passage that connects the space in which the gaseous refrigerant in the main chamber is stored and the space in which the gaseous refrigerant in the second sub chamber is stored, and the second pressure equalizing passage. A second on-off valveIt is characterized by that.
[0009]
[Operation and effect of the invention]
In the first aspect, the liquid refrigerant in the sub chamber is heated by the heat from the heat source means. As a result, the evaporation of the liquid refrigerant in the sub chamber is promoted, and the gas pressure of the gaseous refrigerant on the liquid surface of the liquid refrigerant in the sub chamber increases. Accordingly, a pumping action resulting from the gas pressure of the gaseous refrigerant in the sub chamber is obtained, whereby the liquid refrigerant in the sub chamber is fed to the refrigerant return passage. The liquid refrigerant fed to the refrigerant return passage returns to the main chamber after cooling the cooled part. When returning, the gas pressure in the main chamber, which is the return destination, needs to be lower than the gas pressure in the sub chamber. This is performed by the pressure adjusting means.
[0010]
Further, if the gas pressure in the sub chamber increases excessively than the gas pressure in the main chamber, it may hinder the supply of liquid refrigerant in the main chamber to the sub chamber, but this is corrected by the pressure adjusting means.
In addition, if the gas pressure in the sub chamber increases excessively as described above, the liquid refrigerant in the sub chamber may flow backward to the main chamber through the supply passage. This reverse flow regulates the flow rate of the refrigerant flowing through the supply passage. It is regulated by regulation means with the function to do.
[0011]
As described above, in claim 1, the gas pressure in the sub chamber is increased by promoting the evaporation of the liquid refrigerant in the sub chamber by the heat from the heat source means, thereby generating a pump action, and the liquid refrigerant in the sub chamber is The refrigerant is fed to the refrigerant return passage and returned to the main room, thereby circulating the refrigerant. Thus, in claim 1, since the refrigerant can be circulated without using the impeller type pump, the impeller type pump can be abolished, and the wear of the bearing, the frictional heat generation of the bearing, etc. caused when the impeller type pump is adopted. Can be avoided, and the effect of improving the cooling efficiency can be obtained.
[0012]
According to the second aspect of the present invention, since the restricting means is an on-off valve, a one-way valve or an orifice disposed in the supply passage, the sub-chamber liquid refrigerant is supplied by a flow restricting function of the on-off valve, the one-way valve and the orifice. It is advantageous to prevent backflow through the passage into the main chamber. If an on-off valve or a one-way valve is used as the restricting means, the supply passage can be reliably closed, which is advantageous in preventing the liquid refrigerant in the sub chamber from flowing back to the main chamber through the supply passage. . Further, if an orifice is adopted as the restricting means, the orifice is a throttle mechanism, so that there is substantially no mechanical movable opening / closing mechanism, which is more advantageous for avoiding wear problems during use.
[0013]
  Claim1The pressure adjusting means includes a pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the sub chamber is stored, and an on-off valve that opens and closes the pressure equalizing passage. Has been. Therefore, the pressure equalization passage can be reliably opened by the opening / closing function by the on-off valve, so that the gaseous refrigerant in the sub chamber can be moved to the main chamber in a short time, and thereby the gaseous refrigerant in the main chamber and the gaseous refrigerant in the sub chamber can be moved. The refrigerant can be made to have the same pressure in a short time. Therefore, it is advantageous for supplying the liquid refrigerant in the main chamber to the sub chamber through the supply passage.
[0014]
  Claim3Since a backflow prevention valve for preventing the flow of refrigerant from the refrigerant return passage to the sub chamber is provided in the refrigerant return passage, the refrigerant in the refrigerant return passage is It is possible to prevent backflow into the room. Therefore, it is possible to secure the feeding property of feeding the refrigerant in the sub chamber to the refrigerant return passage, which is advantageous for cooling the cooled part.
[0015]
  As aboveIn each claimAccording to this, the mechanically movable parts are only an on-off valve, a one-way valve, and a backflow prevention valve, and these valves are not continuously driven for 24 hours, unlike the impeller pumps used conventionally. It moves only for a short time intermittently. For example, when the refrigerant in the main chamber is supplied to the sub chamber, the opening operation is performed. Therefore, it is advantageous in terms of wear prevention and is advantageous in improving the durability of the refrigerant supply device.
[0016]
  By the way, when the amount of liquid refrigerant in the sub chamber is large, the efficiency of heating the liquid refrigerant in the sub chamber by the heat source means to promote evaporation is reduced, and the efficiency of increasing the gas pressure of the gaseous refrigerant in the sub chamber is reduced. To do. For example, even if the liquid refrigerant in the sub chamber is heated by heat from the heat source means, if the amount of liquid refrigerant in the sub chamber is large, the liquid refrigerant once heated is cooled by another liquid refrigerant, In the meantime, the temperature returns to a low temperature, and the evaporation amount of the liquid refrigerant is not secured, and there is a problem that the degree of increase in the gas pressure of the gaseous refrigerant in the sub chamber is reduced. This point claim4, A small chamber having a volume smaller than that of the sub chamber is provided in communication with the sub chamber, and the heat source means heats the refrigerant in the small chamber and promotes its evaporation. In this way, since the refrigerant in the small chamber with a small amount of refrigerant is heated, the heating efficiency of the refrigerant is improved, which is advantageous for increasing the gas pressure of the gaseous refrigerant in the sub chamber in a short time. Therefore, it is advantageous for exerting the pump action by the heat source means.
[0017]
  Claim5, The sub chamber is equipped with a float that floats on the liquid refrigerant in the sub chamber, the float has a small volume small chamber into which a part of the liquid refrigerant in the sub chamber enters, and the heat source means is the refrigerant in the small chamber Heat. As described above, since the refrigerant in the small chamber whose amount of refrigerant is smaller than the volume of the sub chamber is heated, the heating efficiency of the refrigerant is improved as described above, and the gas pressure of the gaseous refrigerant in the sub chamber is increased in a short time. Is advantageous. Therefore, it is advantageous for exerting the pump action by the heat source means.
[0018]
  Claim6According to the above, even when the liquid refrigerant is being replenished from the main chamber to one of the first and second sub chambers, the other sub chamber is heated to transfer the liquid refrigerant in the other sub chamber to the refrigerant return passage. Can be sent to. Therefore, the part to be cooled can be efficiently cooled.
[0019]
【Example】
Example 1
FIG. 1 shows a first embodiment of the present invention.
As shown in FIG. 1, a large-volume refrigerant main tank 10 constituting a main chamber and a small-volume refrigerant sub-tank 3 constituting a sub chamber are arranged. Both sides contain a liquid refrigerant composed of cryogenic liquid nitrogen. The liquid phase part 10a of the refrigerant main tank 10 communicates with the lower part of the refrigerant sub tank 3 through a supply valve 5 and a supply passage 5n as on-off valves. The refrigerant main tank 10 communicates with the upper part of the refrigerant sub tank 3 through a pressure equalizing valve 4 and a pressure equalizing passage 4n serving as on-off valves. As can be understood from FIG. 1, one end 4a of the pressure equalizing passage 4n is connected to a position higher than the connection port 5x between the supply passage 5n and the refrigerant sub-tank 3, and the supply passage 5n, the refrigerant main tank 10, The other end 4b of the pressure equalizing passage 4n is connected to a position higher than the connection port 5y.
[0020]
A conduit 6 is connected to the bottom of the liquid phase portion 3 a of the refrigerant sub tank 3. The middle part of the conduit 6 is in thermal contact with the shield plate 11 as a part to be cooled. The other end of the conduit 6 communicates with the inlet of the condenser 7. The condenser 7 has an increased heat exchange area and is cooled by heat exchange with the low temperature portion 1 of the refrigerator 1p that can generate refrigeration. Further, the gas phase portion 10b of the refrigerant main tank 10 is provided with a heat exchanger 9 having an increased heat exchange area. The outlet of the condenser 7 communicates with the heat exchanger 9 via a conduit 8. The conduits 6, 8, the condenser 7, and the heat exchanger 9 constitute a refrigerant return passage for returning the refrigerant to the refrigerant main tank 10.
[0021]
Further, a heat source 12 (heat source means) is provided so as to be immersed in the liquid refrigerant so that the liquid refrigerant in the liquid phase portion 3a of the refrigerant sub-tank 3 can be heated. In this embodiment, the heat source 12 is an electric heater system, and includes a heating wire and an insulating coating layer that covers the heating wire. The heat source 12 is provided in the refrigerant sub-tank 3 so as to be immersed in the liquid refrigerant. However, the heat source 12 may be provided outside the refrigerant sub-tank 3 or both.
[0022]
Now, even if the gas pressure of the gas phase portion 3b of the refrigerant sub-tank 3 is higher than the gas pressure of the gas phase portion 10b of the refrigerant main tank 10, the pressure equalizing passage 4n communicates if the pressure equalizing valve 4 is opened. Therefore, the gas pressure of the gas phase part 3b of the refrigerant sub tank 3 and the gas pressure of the gas phase part 10b of the refrigerant main tank 10 are basically the same pressure. Therefore, the pressure equalizing valve 4 functions as pressure adjusting means for adjusting the gas pressure of the gas phase portion 3b of the refrigerant sub tank 3 and the gas phase portion 10b of the refrigerant main tank 10.
[0023]
Thus, if the supply valve 5 is opened with the gas phase portion 3b and the gas phase portion 10b being at the same pressure, the liquid refrigerant in the liquid phase portion 10a of the refrigerant main tank 10 having a high liquid level will have its liquid head pressure. Thus, the refrigerant flows into the refrigerant sub-tank 3 having a low liquid level. Therefore, the liquid level of the liquid refrigerant in the liquid phase part 3 a of the refrigerant sub-tank 3 is automatically supplied until the liquid level of the liquid refrigerant in the liquid phase part 10 a of the refrigerant main tank 10 becomes the same level.
[0024]
Next, the pressure equalizing valve 4 and the supply valve 5 are closed. In this state, if the liquid refrigerant in the liquid phase portion 3a of the refrigerant sub-tank 3 is heated by the heat from the heat source 12, evaporation of the liquid refrigerant in the liquid phase portion 3a is promoted. As a result, the gas pressure P1 of the gas phase part 3b of the refrigerant sub tank 3 becomes higher than the gas pressure P2 of the gas phase part 10b of the refrigerant main tank 10 as a return destination. Therefore, the pump action resulting from the differential pressure (P1-P2) between the two is obtained, and the liquid refrigerant in the liquid phase portion 3a of the refrigerant sub tank 3 flows into the conduit 6 and cools the shield plate 11.
[0025]
At this time, part or all of the liquid refrigerant evaporates due to heat exchange with the shield plate 11 and flows into the condenser 7. The refrigerant flowing into the condenser 7 is further cooled by refrigeration generated in the low temperature part 1 of the refrigerator 1p, and liquefaction is promoted. Therefore, in the condenser 7, the refrigerant has a lower temperature than the gas phase portion 10 b in the refrigerant main tank 10. Thus, the refrigerant cooled in the low temperature part 1 returns to the refrigerant main tank 10 through the conduit 8 and the heat exchanger 9. In this way, the refrigerant is circulated.
[0026]
By the way, the liquid refrigerant in the liquid phase part 10a of the refrigerant main tank 10 evaporates due to the influence of heat (conduction heat, radiant heat, etc.) entering the refrigerant main tank 10 from the outside, and the gas phase part 10b in the refrigerant main tank 10 evaporates. The gas pressure tends to be excessively high. Thus, if the gas pressure of the gas phase portion 10b becomes excessively high, the gas pressure P2 of the gas phase portion 10b of the refrigerant main tank 10 as a return destination is higher than the gas pressure P1 of the gas phase portion 3b of the refrigerant subtank 3. Get higher. As a result, the refrigerant in the refrigerant sub-tank 3 cannot flow into the heat exchanger 9 through the conduits 6 and 8, that is, the refrigerant fed from the refrigerant sub-tank 3 cannot be returned to the refrigerant main tank 10.
[0027]
In this respect, in this embodiment, the refrigerant flowing into the heat exchanger 9 is cooled to a lower temperature in the low temperature portion 1 of the refrigerator 1p as described above, so that the low temperature property of the heat exchanger 9 is maintained. Therefore, in the heat exchanger 9, the gaseous refrigerant in the gas phase portion 10b in the refrigerant main tank 10 can be effectively cooled and liquefied. The liquefied refrigerant falls to the liquid phase part 10 a in the refrigerant main tank 10. Accordingly, it is possible to prevent an excessive increase in the gas pressure of the gas phase portion 10 b in the refrigerant main tank 10, and as a result, return of the refrigerant from the refrigerant sub tank 3 to the refrigerant main tank 10 is ensured.
[0028]
Further, in this embodiment, the liquid refrigerant in the liquid phase portion 3a of the refrigerant sub tank 3 becomes insufficient with use, and the liquid level is lowered. In this case, it is necessary to replenish the refrigerant sub tank 3 with the liquid refrigerant in the refrigerant main tank 10. Therefore, the pressure equalizing valve 4 is opened again. When the pressure equalizing valve 4 is opened, the pressure equalizing passage 4n is communicated as described above, so that the gas pressure in the gas phase portion 3b of the refrigerant sub-tank 3 and the gas pressure in the gas phase portion 10b of the refrigerant main tank 10 are reduced in a short time. It becomes the same pressure. When the supply valve 5 is opened in this state, the supply passage 5n communicates, and the liquid refrigerant in the liquid phase portion 10a of the refrigerant main tank 10 passes through the supply passage 5n and the supply valve 5 due to liquid head pressure, and the liquid in the refrigerant sub tank 3 The phase part 3a is immediately replenished.
[0029]
As described above, in the present embodiment, the liquid refrigerant in the refrigerant main tank 10 can be circulated and reused by the pump action by the heat from the heat source 12, so that the liquid refrigerant can be operated without being replenished from the outside, or is replenished. However, the replenishment amount of the liquid refrigerant can be reduced, which is advantageous for cost reduction.
By the way, in this embodiment, the mechanical movable mechanism is only the pressure equalizing valve 4 and the supply valve 5, and the pressure equalizing valve 4 and the supply valve 5 are not continuously moving unlike the bearings of the conventional impeller type pump. When the liquid refrigerant in the refrigerant main tank 10 is replenished to the refrigerant sub tank 3, it is only temporarily opened. Accordingly, the operation time of the pressure equalizing valve 4 and the supply valve 5 is shortened, and the wear in the pressure equalizing valve 4 and the supply valve 5 can be eliminated or greatly reduced. Problems caused by wear and frictional heat generation can be eliminated, and the durability of the cooling device can be reduced. It is advantageous for improvement.
[0030]
As described above, in this embodiment, when the amount of heat is supplied to the heat source 12 and the liquid refrigerant in the liquid phase portion 3a of the refrigerant subtank 3 is evaporated, the gas pressure in the gas phase portion 3a of the refrigerant subtank 3 is increased. The pump pressure can be obtained. Since the pump pressure can be obtained in this way, it is possible to avoid or reduce the backflow of the refrigerant in the conduit 6 to the refrigerant subtank 3, that is, the liquid refrigerant can be reliably supplied to the conduit 6 and the shield plate 11 is cooled. High efficiency.
[0031]
As described above, when heat is applied by the heat source 12 when both the supply valve 5 and the pressure equalizing valve 4 are closed, the gas pressure in the gas phase portion 3b of the refrigerant sub-tank 3 can be effectively increased. Therefore, the pump efficiency is improved, and it is advantageous for avoiding the back flow from the conduit 6 to the refrigerant sub tank 3.
In some cases, the heat source 12 may be always turned on to constantly apply heat to the refrigerant sub-tank 3.
[0032]
In this embodiment, the pressure equalizing valve 4 and the supply valve 5 can be opened and closed manually or controlled by a control device.
In the example shown in FIG. 1, the refrigerant main tank 10 can also be arranged at a position higher than the refrigerant sub tank 3. In this case, the potential energy of the liquid refrigerant in the refrigerant main tank 10 increases. Therefore, when the supply valve 5 is opened, the liquid refrigerant in the refrigerant main tank 10 can be easily replenished to the refrigerant sub tank 3, and it is advantageous for avoiding the liquid refrigerant in the refrigerant sub tank 3 from flowing back to the refrigerant main tank 10. is there.
[0033]
The supply valve 5, the pressure equalizing valve 4, etc. may break down. This can be done as follows. That is, if an emergency air release valve is disposed between the conduit 6 and the condenser 7 and an emergency on-off valve is disposed downstream of the condenser 7, the supply valve 5 and the leveling valve should be provided. Even when at least one of the pressure valves 4 fails, the shield plate 11 can be cooled. In other words, even if at least one of the supply valve 5 and the pressure equalizing valve 4 fails, the supply valve 5 and the pressure equalizing valve 4 are opened, and the emergency atmosphere release valve is opened. If the liquid refrigerant in the refrigerant main tank 10 is discharged from the emergency air release valve to the atmosphere until the liquid refrigerant in the refrigerant main tank 10 is emptied by closing the emergency on-off valve, It can be expected that the shield plate 11 is cooled by the refrigerant flowing through the conduit 6.
[0034]
(Application example)
FIG. 2 shows an application example. This example includes a container 20 that contains a superconducting magnet 21, a room-temperature-side vacuum tank 25 disposed outside the container 20, and a liquid helium tank 20a in which liquid helium is stored. The liquid helium in the liquid helium tank 20a is loaded in the container 20, whereby the superconducting magnet 21 accommodated in the container 20 is maintained at an extremely low temperature of about 4.4K.
[0035]
Further, in order to prevent radiant heat and conduction heat entering the container 20 from the vacuum chamber 25, the shield plate 11 as a portion to be cooled is covered around the container 20 housing the superconducting magnet 21. In this example, the shield plate 11 is cooled by supplying liquid refrigerant composed of liquid nitrogen in the refrigerant sub-tank 3 to the conduit 6 that is in thermal contact with the shield plate 11. Thereby, the cryogenic properties of the container 20 and the superconducting magnet 21 are easily maintained.
[0036]
In this example, as can be understood from FIG. 2, the refrigerant main tank 10 is fixed to the vacuum tank 25 via the heat insulating support 16.
Here, the container 20 is fixed to the vacuum chamber 25 via the heat insulating support members 23 and 23 a, the shield plate 11, and the heat insulating support member 24. In FIG. 2, 30 is a refrigerator equipped with a Joule-Thomson circuit for producing liquid helium, 30a is a compressor, 32 is a first stage expansion space for generating a cryogenic temperature, and 31 is a cryogenic cryogenic temperature. The second stage expansion space, 33 is a precooling heat exchanger, 34a is a helium low pressure conduit, 34b is a helium high pressure conduit, and 34w is a Joule Thomson valve.
[0037]
As the refrigerator 1p shown in FIG. 2, a Joule-Thompson circuit refrigerator 30 for producing liquid helium may be used in combination. That is, the condenser 7 constituting the refrigerant return passage may be brought into thermal contact with at least one of the expansion spaces 32 and 33 of the refrigerator 30. Thereby, since the refrigerator 1p shown in FIG. 2 becomes unnecessary, it becomes more advantageous in terms of cost, mass, occupied space, required power, and the like.
[0038]
(Operation of pressure equalization valve 4 and supply valve 5)
The opening / closing operation of the pressure equalizing valve 4 and the supply valve 5 will be further described with reference to FIG. Basically, the opening of the pressure equalizing valve 4 and the opening of the supply valve 5 overlap in time, and the closing of the pressure equalizing valve 4 and the closing of the supply valve 5 overlap in time. However, the pressure equalizing valve 4 and the supply valve 5 can be opened and closed in various forms shown in FIGS.
[0039]
FIG. 3A shows a case where the pressure equalizing valve 4 and the supply valve 5 are opened and closed simultaneously in time, and immediately after the pressure equalizing valve 4 and the supply valve 5 are opened, the gaseous refrigerant in the gas phase portion 3b of the refrigerant subtank 3 is shown. Flows into the gas phase portion 10b of the refrigerant main tank 10 through the pressure equalizing passage 4n and the pressure equalizing valve 4, and the gas phase portion 3b and the gas phase portion 10b have the same pressure. As a result, the liquid refrigerant in the liquid phase portion 10 a of the refrigerant main tank 10 flows into the refrigerant sub tank 3 through the supply valve 5.
[0040]
FIG. 3B shows a case where the supply valve 5 is opened (ΔT1) slightly behind the pressure equalizing valve 4 and the pressure equalizing valve 4 and the supply valve 5 are simultaneously closed. In this case, immediately after the pressure equalizing valve 4 is opened, the gaseous refrigerant in the gas phase portion 3 b of the refrigerant subtank 3 flows into the refrigerant main tank 10 through the pressure equalizing valve 4, and the gas phase portion 3 b of the refrigerant subtank 3. And the gas phase portion 10b of the refrigerant main tank 10 have the same pressure. In the form shown in FIG. 3B, the supply valve 5 is opened after the pressure becomes the same as described above. Backflow to the liquid phase part 10a of the tank 10 can be reliably prevented.
[0041]
FIG. 3C shows a case where the supply valve 5 is opened slightly earlier (ΔT2) than the pressure equalizing valve 4 and the pressure equalizing valve 4 and the supply valve 5 are simultaneously closed. In this case, after the supply valve 5 is opened, the pressure equalizing valve 4 is opened after lapse of ΔT2. Since the opening of the pressure equalizing valve 4 is delayed by ΔT2 in this manner, the liquid in the refrigerant sub-tank 3 is kept until the pressure of the gas phase part 3b of the refrigerant sub-tank 3 and the gas phase part 10b of the refrigerant main tank 10 become the same pressure. The refrigerant may flow back to the refrigerant main tank 10. Such a backflow can be used as follows depending on circumstances. That is, it is advantageous for returning the excess liquid refrigerant in the refrigerant sub-tank 3 whose temperature is slightly raised by the heat source 12 to the refrigerant main tank 10 on the cryogenic temperature side.
[0042]
FIG. 3D shows a case where the pressure equalizing valve 4 and the supply valve 5 are simultaneously opened and the supply valve 5 is closed slightly earlier (ΔT3) than the pressure equalizing valve 4. In ΔT3 time, although the pressure equalizing valve 4 is open but the supply valve 5 is already closed, the liquid refrigerant in the liquid phase portion 3a of the refrigerant sub tank 3 does not flow back to the refrigerant main tank 10.
FIG. 3E shows a case where the pressure equalizing valve 4 and the supply valve 5 are simultaneously opened and the supply valve 5 is closed slightly later (ΔT4) than the pressure equalizing valve 4.
[0043]
Since a certain amount of time is required for the pressure in the gas phase portion 3b of the refrigerant sub tank 3 to rise, even if the supply valve 5 is closed slightly later than the pressure equalizing valve 4 (after ΔT4), the ΔT4 time is short. If it is time, the amount of the liquid refrigerant that flows back from the refrigerant secondary cup 3 to the refrigerant main pipe 10 is very small, and there is substantially no problem.
(Example 2)
FIG. 4 shows a second embodiment. This example has basically the same configuration as that of the first embodiment, and has the same effects. Furthermore, this example has the following features. That is, when the heat capacity of the shield plate 11 as the cooled portion is small, the shield plate 11 is easily heated by the influence of external heat. In this case, when the pumping action by the heat source 12 is suspended, that is, when the supply of the liquid refrigerant from the cooling sub-tank 3 to the conduit 6 is suspended (that is, the supply valve 5 and the pressure equalizing valve 4 are opened, the refrigerant main When the liquid refrigerant in the tank 10 is replenished to the refrigerant sub-tank 3), the refrigerant in the conduit 6 is heated and evaporated by the heat transfer from the heated shield plate 11, and the pressure in the conduit 6 rapidly rises. The pressure of 6 may be higher than the pressure of the refrigerant sub-tank 3, so that a normal pumping action cannot be obtained. In this case, the refrigerant is not normally supplied to the shield plate 11, and the refrigerant in the conduit 6 may flow backward to the refrigerant sub tank 3. In this case, the refrigerant supply to the conduit 6 is hindered, and the efficiency of cooling the shield plate 11 that is the part to be cooled is reduced. Therefore, as shown in FIG. 4, a backflow prevention valve 13 is provided between the refrigerant subtank 3 and the conduit 6, and when the supply of the liquid refrigerant from the refrigerant subtank 3 to the conduit 6 is stopped, the backflow prevention valve 13 is provided. To prevent backflow.
[0044]
In this way, even if the heat capacity of the shield plate 11 as the cooled portion is small and the shield plate 11 is likely to rise in temperature, the refrigerant in the conduit 6 can be prevented from flowing back into the refrigerant sub-tank 3, and the shield plate 11 can be effectively cooled.
(Example 3)
FIG. 5 shows a third embodiment. This example also basically has the same configuration as that of the first embodiment, and has the same effects.
[0045]
In this example, instead of the check valve 13 shown in FIG. 4, a one-way valve 13 a is adopted so that the refrigerant flows only in the direction from the refrigerant subtank 3 to the conduit 6, and from the conduit 6 to the refrigerant subtank 3. Keeps the refrigerant from flowing. If a one-way valve is employed as the supply valve 5 as shown in FIG. 5, the refrigerant subtank when the pressure of the gas phase part 3 b of the refrigerant subtank 3 is higher than the pressure of the gas phase part 10 b of the refrigerant main tank 10. 3 can prevent the liquid refrigerant from flowing back to the refrigerant main tank 10.
[0046]
Example 4
FIG. 6 shows a fourth embodiment. This example has basically the same configuration as that of the first embodiment, and has the same effects. In this example, an atmosphere release valve 14 that communicates with the gas phase portion 10b of the refrigerant main tank 10 is provided, and when the pressure of the gas phase portion 10b of the refrigerant main tank 10 exceeds a predetermined pressure, the atmosphere release valve 14 is automatically turned on. It was designed to be open.
[0047]
When the heat is received from the shield plate 11, the refrigerant in the conduit 6 may partially evaporate and gasify. Here, when the amount of refrigeration generated in the low temperature portion 1 of the refrigerator 1p is reduced or when the refrigeration capacity of the refrigerator 1p is small, the refrigerant partially evaporated in the conduit 6 is sufficiently liquefied in the condenser 7. However, a part of the refrigerant flows in the gas phase part 10b of the refrigerant main tank 10 through the conduit 8 and the heat exchanger 9 as evaporative gas, so that the pressure of the gas phase part 10b of the refrigerant main tank 10 is high. Tend to be. As a result, the gas pressure of the gas phase portion 10b of the refrigerant main tank 10 that is the refrigerant return destination becomes excessively high, the temperature of the circulating liquid refrigerant rises above the appropriate temperature, and the temperature of the shield plate 11 becomes high. Occurs. Moreover, the gas pressure of the refrigerant | coolant main tank 10 and the refrigerant | coolant subtank 3 rises abnormally, and the malfunction that the refrigerant | coolant main tank 10 and the refrigerant | coolant subtank 3 may destroy will arise. Therefore, in this example, when the gas phase portion 10b of the refrigerant main tank 10 reaches a predetermined pressure or higher, the atmosphere release valve 14 is automatically opened, and the excess pressure of the gaseous refrigerant in the refrigerant main tank 10 is increased to the atmosphere release valve 14. Through to the atmosphere. Therefore, in this example, even if the amount of refrigeration generated in the low temperature portion 1 of the refrigerator 1p is reduced, the refrigerant main tank 10 and the refrigerant sub tank 3 can be prevented from being destroyed.
[0048]
The air release valve 14 functions as a pressure adjusting means for adjusting the gas pressure in the gas phase portion 10b of the refrigerant main tank 10. The air release valve 14 may be a pressure-responsive relief valve that opens naturally against the spring force of the spring when a predetermined pressure or higher is reached, or operates by electromagnetic force, electric force, pneumatic pressure, hydraulic pressure, or the like. A valve may be used.
(Example 5)
The fifth embodiment shown in FIG. 7 is a modification of the fourth embodiment, and employs an atmosphere communication pipe 15 (pressure adjusting means) that is always in communication with the atmosphere instead of the atmosphere release valve 14.
[0049]
When the shield plate 11 is cooled by heat exchange, the liquid refrigerant in the conduit 6 evaporates a part of the refrigerant to form a two-phase flow of liquid and vapor and flows into the gas phase portion 10b of the refrigerant main tank 10 as described above. It is as follows. In the refrigerant main tank 10, the liquid refrigerant is accumulated in the liquid phase portion 10 a, and only the excess gaseous refrigerant is discharged to the atmosphere through the atmosphere communication pipe 15. Therefore, while preventing excessive pressure in the gas phase portion 10b of the refrigerant main tank 10, the liquid refrigerant is not wastefully discharged into the atmosphere, which is advantageous for effective use of the liquid refrigerant. In other words, even when the refrigerator 1p is not provided, it is possible to prevent the pressure of the gas phase portion 10b of the refrigerant main tank 10 from being excessive, so that a good pump circulation action by the heat source 12 can be obtained. By this, the liquid refrigerant can be reliably fed to the conduit 6 and the shield plate 11 can be cooled efficiently.
(Example 6)
8 and 9 show a sixth embodiment. This example also has the same configuration as that of the first embodiment, and has the same effects.
[0050]
In this example, two refrigerant subtanks 102 and 103 are provided in parallel. The refrigerant sub tank 102 functions as a first sub chamber, and the refrigerant sub tank 103 functions as a second sub chamber. There is one refrigerant main tank 112 functioning as a main chamber containing a low-temperature liquid refrigerant such as liquid nitrogen. The liquid phase portion 112a of the refrigerant main tank 112 is connected to the liquid phase portion 102a of the refrigerant subtank 102 via the first supply passage 106n and the supply valve 106 as the first regulating means, and the pressure equalization passage 104n and the first pressure passage 104n. 1 It connects to the gas phase part 102b of the refrigerant | coolant subtank 102 via the pressure equalization valve 104 as a pressure adjustment means.
[0051]
The liquid phase part 112a of the refrigerant main tank 112 is connected to the liquid phase part 103a of the refrigerant sub tank 103 via the second supply passage 107n and the supply valve 107 as the second regulating means, and the pressure equalization passage 105n and It is connected to the gas phase portion 103b of the refrigerant sub tank 103 through a pressure equalizing valve 105 as a second pressure adjusting means.
A pressure-responsive one-way valve 117 as a first backflow prevention valve is provided in the conduit 108x that connects the liquid phase portion 102a of the refrigerant sub tank 102 and the conduit 108. A pressure-responsive one-way valve 118 as a second backflow prevention valve is provided in the sub-passage 118y that connects the liquid phase portion 103a of the refrigerant sub-tank 103 and the conduit 108. Therefore, the liquid refrigerant flows only in the direction from the refrigerant sub tanks 102 and 103 toward the conduit 108, and does not flow in the opposite direction.
[0052]
The conduit 108 is in thermal contact with a shield plate 113 as a part to be cooled. The outlet of the condenser 109 communicates with the heat exchanger 111 of the gas phase portion 112b of the refrigerant main tank 112 via the conduit 110. Accordingly, in FIG. 8, the conduits 108 x and 108, the condenser 109, the conduit 110, and the heat exchanger 111 constitute a main passage for returning the liquid refrigerant in the refrigerant sub tank 102 to the refrigerant main tank 112.
[0053]
Further, a heat source 114 as a first heat source means and a heat source 115 as a second heat source means are provided so that heat is transmitted to the liquid phase portions 102a and 103a of the refrigerant subtanks 102 and 103, respectively. The heat sources 114 and 115 are provided inside the refrigerant sub tanks 102 and 103, but may be provided outside or both.
As shown in FIG. 9, the refrigerant main tank 112 is fixed to the vacuum tank 25 via a heat insulating support material 116. Liquid helium in the liquid helium tank 20a is charged in the container 20, and the superconducting magnet 21 is cooled to about 4.4K. The shield plate 113 as a part to be cooled covers the periphery of the container 20 containing the superconducting magnet 21, thereby making it easy to maintain the cryogenicity of the container 20 and the superconducting magnet 21. The container 20 is fixed to the vacuum chamber 25 on the room temperature side through the heat insulating support members 23 and 23 a, the shield plate 113, and the heat insulating support member 24.
[0054]
In this example as well, as can be understood from FIG. 8, the liquid refrigerant in the liquid phase portion 112a of the refrigerant main tank 112 is sequentially supplied to the refrigerant sub tanks 102 and 103, the one-way valves 117 and 118, the conduit 108, the condenser 109, It is fed to the conduit 110 and the heat exchanger 111 and returns to the refrigerant main tank 112.
In this example, when the liquid refrigerant in the refrigerant main tank 112 is replenished to one refrigerant sub tank 102 in FIG. 8 (that is, when the pressure equalizing valve 104 and the supply valve 106 are open), the pump by the heat of the heat source 115 is used. As a result, the liquid refrigerant in the other refrigerant sub-tank 103 is fed to the conduit 108 through the one-way valve 118 (that is, when the pressure equalizing valve 105 and the supply valve 107 are closed).
[0055]
Conversely, when liquid refrigerant in the refrigerant main tank 112 is being supplied to the other refrigerant sub tank 103 (that is, when the pressure equalizing valve 105 and the supply valve 107 are open), The liquid refrigerant in the refrigerant sub tank 102 is fed to the conduit 108x and the conduit 108 through the one-way valve 117 (that is, when the pressure equalizing valve 104 and the supply valve 106 are closed).
[0056]
In this example, as described above, the pump action is alternately obtained in both the refrigerant sub-tanks 103 and 102, so that the liquid refrigerant can be continuously supplied to the conduit 108x and the conduit 108 without interruption. In this example as well, the liquid refrigerant can be returned to the refrigerant main tank 112 and circulated. Therefore, the refrigerant can be reused in the same manner as in the above-described embodiment, so that it is possible to avoid replenishing the refrigerant from the outside. That's it.
[0057]
FIG. 10 is a time chart showing the open / close state of the pressure equalizing valve 104 and the supply valve 106 and the open / closed state of the pressure equalizing valve 105 and the supply valve 107. Each valve can be opened and closed in various forms shown in FIGS.
10A shows that the pressure equalizing valve 105 and the supply valve 107 are closed when the pressure equalizing valve 104 and the supply valve 106 are open, and the pressure equalizing valve 105 and the supply valve 107 are closed when the pressure equalizing valve 104 and the supply valve 106 are closed. It is a case where it is made to open. In the form shown in FIG. 10 (A), the pump action is obtained alternately in both the refrigerant sub-tanks 103 and 102, which is advantageous for continuously feeding the liquid refrigerant to the conduit 108x and the conduit 108 without interruption. is there.
[0058]
FIG. 10B shows a case where the pressure equalizing valve 104 and the supply valve 106 are opened and closed, and at the same time the pressure equalizing valve 105 and the supply valve 107 are opened. The form shown in FIG. 10B is also advantageous for continuously feeding the liquid refrigerant to the conduit 108 without interruption because the pump action is obtained alternately in both the refrigerant sub-tanks 103 and 102.
FIG. 10C shows a case where the pressure equalizing valve 105 and the supply valve 107 are opened slightly before the pressure equalizing valve 104 and the supply valve 106 are closed from opening (ΔT6). In this embodiment, the liquid refrigerant is not supplied to the conduit 108 in a short time (ΔT6) when the pressure equalizing valve 104 and the supply valve 106, and the pressure equalizing valve 105 and the supply valve 107 are simultaneously opened.
[0059]
In addition, although the example shown in FIG. 8 is an example which provided the two refrigerant | coolant subtanks 102 and 103, it is not limited to this, Three or more refrigerant | coolant subtanks may be sufficient.
(Example 7)
In Example 7 (not shown), the one-way valves 117 and 118 shown in FIG. 8 are operated with electromagnetic force, electric force, pneumatic pressure, hydraulic pressure, etc. (the same type as the check valve 13 shown in FIG. 4). Has been replaced. The supply valves 106 and 107 may be replaced with one-way valves.
[0060]
(Example 8)
In Example 8 shown in FIG. 11, an atmosphere release valve 121 (same as the atmosphere release valve 14 in the example shown in FIG. 6) is provided in the gas phase portion 112 b of the refrigerant main tank 112. Then, when the pressure of the gas phase portion 112b of the refrigerant main tank 112 becomes equal to or higher than a predetermined pressure, the atmosphere release valve 121 is opened. The air release valve 121 may be a relief valve that opens when a predetermined pressure is exceeded by a spring force, or a valve that is operated by electromagnetic force, electric force, pneumatic pressure, hydraulic pressure, or the like.
[0061]
Example 9
FIG. 12 shows a ninth embodiment. In this example, the gas phase portion 203b and the liquid phase portion 203a are communicated with each other by a vertical communication pipe 202 in the refrigerant subtank 203 as the subtank. The cross-sectional area of the communication pipe 202 is made smaller than the cross-sectional area of the refrigerant sub tank 203. Therefore, the communication pipe 202 constitutes a small chamber. A heat source 205 is provided on the outer surface of the communication pipe 202. In this way, since a small amount of liquid refrigerant in the communication pipe 202 may be heated by the heat source 205, the heating efficiency is improved, and the liquid refrigerant in the communication pipe 202 can be simply supplied to the heat source 205. Can be evaporated in a short time, and therefore the pressure of the gas phase portion 203b can be increased in a short time, and a good pumping action can be obtained.
[0062]
By the way, when the liquid level of the liquid refrigerant in the refrigerant sub-tank 203 is shaken due to vibration or impact, even if the liquid refrigerant in the refrigerant sub-tank 203 is heated by the heat source 205, the heated liquid refrigerant remains at the liquid level. The mixture is agitated along with the swinging of the liquid and becomes a low temperature again, whereby the evaporation of the refrigerant is not promoted, and a sufficient pumping action may not be obtained. In this respect, in this example, since the float 204 is suspended in the liquid refrigerant in the refrigerant sub-tank 203, the float 204 can effectively prevent the liquid refrigerant from shaking, and the above-described problems can be reduced or avoided. Therefore, when the present cooling device is applied to a traveling vehicle such as a magnetically levitated vehicle, the liquid level of the liquid refrigerant in the refrigerant sub-tank 203 can be effectively prevented, which is advantageous. Reference numeral 200 denotes a refrigerator, and 201 denotes a refrigeration generator.
[0063]
Furthermore, in this example, the float 204 floats on the liquid refrigerant level in the refrigerant sub-tank 203, and the height H1 (see FIG. 12) of the float 204 from the liquid refrigerant level is high. Therefore, the volume of the gas phase portion 203b of the refrigerant sub tank 203 is reduced that much. Therefore, it is advantageous to increase the gas pressure of the gas phase portion 203b in a short time by the heat from the heat source 205, and the responsiveness of the pump action can be improved.
[0064]
(Example 10)
In the tenth embodiment shown in FIG. 13, a heating heater 205 a is employed as a heat source, and the heating heater 205 a is fixed to the communication pipe 202. The lead wires 207 and 208 at both ends of the heater 205a are connected to a power source 209 outside the vacuum chamber 25 through a hermetic seal 211 that is airtightly fixed to the vacuum chamber 25.
[0065]
Also in this example, the float 204 is floating as described above, the volume of the gas phase portion 203b of the refrigerant sub-tank 203 is reduced by that amount, and the gas pressure of the gas phase portion 203b is reduced within a short time due to the heat generated by the heater 205a. It is advantageous to increase.
(Example 11)
In Example 11 shown in FIG. 14, a heat conductive plate 205b (a copper plate, an aluminum plate, a flat mesh copper wire, etc.) having a good thermal conductivity is provided as a heat source. One end of the heat conducting plate 205 b is fixed to the communication pipe 202, and the other end is connected to a place where the temperature is higher than the communication pipe 202, for example, the vacuum chamber 25. In this example, since the volume of the communication pipe 202 is smaller than the volume of the refrigerant sub chamber 203, the liquid refrigerant in the communication pipe 202 is effectively heated by the heat from the heat conduction plate 205b, and evaporation is promoted.
[0066]
(Example 12)
In Example 12 shown in FIG. 15, the float 204 is floated on the liquid refrigerant level in the refrigerant sub-tank 203, and the small float 217 is floated on the liquid refrigerant level in the communication pipe 202. A heat generating heater 206 is wound around the shaft portion of the float 217 immersed in the liquid refrigerant in a coil shape as a heat source, and both ends of the heat generating heater 206 are connected via lead wires 207 and 208 and hermetic seals 210 and 211, The power supply 209 provided outside the vacuum chamber 25 is connected.
[0067]
In this example, since the float 217 floating on the liquid refrigerant liquid level of the communication pipe 202 is equipped with the heat generating heater 206, the liquid refrigerant in the vicinity of the liquid level of the communication pipe 202 can be heated intensively. It is advantageous for securing, and it is advantageous for obtaining a good pumping action. In this example, one refrigerant sub-tank 203 is provided, but not limited to this, two or more refrigerant sub-tanks 203 may be used.
[0068]
(Example 13)
FIG. 16 shows a thirteenth embodiment. A heat source 215 is provided on the outer surface or inside of the refrigerant sub tank 203. Since the heat source 215 is located near the liquid level of the liquid refrigerant in the refrigerant sub tank 203, the liquid refrigerant near the liquid level can be intensively heated, and the pressure of the gas phase portion 203b of the refrigerant sub tank 203 is efficiently increased. This provides a good pumping action and can deliver liquid refrigerant to the conduit 212. The heat source 215 may be a heat generating heater or a member having good heat conduction, for example, a conductive plate such as a copper plate, an aluminum plate, or a flat mesh copper wire.
[0069]
(Example 14)
FIG. 17 shows a fourteenth embodiment. In this example, the float 214 floats in the liquid refrigerant in the refrigerant sub tank 203, and a small chamber 214 b having a small volume is provided inside the float 214. A heating heater 216 is disposed as a heat source in the liquid refrigerant in the small chamber 214b. A communication hole 214a is provided in the lower surface of the small chamber 214b, and a gas hole 214c in communication with the gas phase portion 203b is provided in the upper surface. The lead wires 207 and 208 at both ends of the heater 216 are connected to a power source 209 outside the vacuum chamber 25 via hermetic seals 210 and 211.
[0070]
Note that when the gaseous refrigerant heated and evaporated by the heater 216 flows into the cryogenic liquid phase portion 203a, the once heated refrigerant comes into contact with another liquid refrigerant to be cooled again and liquefied. It is difficult for the pressure of the portion 203b to increase, and it is difficult to obtain a good pumping action. In this respect, in this example, the gaseous refrigerant heated and evaporated by the heater 216 flows into the gas phase part 203b of the refrigerant sub tank 203 through the gas hole 214c formed in the float 214, and the pressure of the gas phase part 203b is increased. It is advantageous to increase and obtain a good pumping action. The liquid refrigerant in the refrigerant sub-tank 203 is fed to the conduit 6 through the one-way valve 13a as a backflow prevention valve by the pump action.
[0071]
Furthermore, in this example, since a small amount of liquid refrigerant in the small chamber 214b only needs to be heated, the pressure of the gas phase portion 203b can be increased in a short time by simply supplying a small amount of heat to the heater 216. Can demonstrate.
(Example 15)
FIG. 18 shows a fifteenth embodiment. A first super-insulation 224 is wound in multiple layers on the outer surface of the refrigerant main tank 223 in a region facing the vacuum tank 25. Furthermore, the conduits 212 and 212x are brought into thermal contact with the outer surface of the first super-insulation 224. Further, the second super insulation 225 is wound in multiple layers on the outer surface side of the conduits 212 and 212x. The super-insulations 224 and 225 are obtained by laminating an aluminum vapor deposition film that reflects radiant heat and a resin spacer having heat insulation properties. Here, the liquid refrigerant pumped from the refrigerant sub tank 203 flows in the conduits 212 and 212x. In this way, since the super-insulations 224 and 225 are cooled by the liquid refrigerant flowing in the conduits 212 and 212x, the outer surface temperature of the first super-insulation 224 is the liquid phase part 223a of the refrigerant main tank 223. It becomes substantially equal to the temperature of the liquid refrigerant. As a result, it is possible to effectively prevent external heat from entering the refrigerant main tank 223 from the first super insulation 224, which is advantageous for maintaining the cryogenic temperature of the refrigerant main tank 223.
[0072]
The refrigerant main tank 223 is fixed to the vacuum tank 25 via a heat insulating support member 222, a shield plate 220, and a heat insulating support member 222.
In addition, the present invention is not limited only to the embodiments described above and shown in the drawings, and can be appropriately selected as necessary without departing from the scope of the invention.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an apparatus according to a first embodiment.
FIG. 2 is a cross-sectional view of a superconducting magnet device according to an application example.
FIG. 3 is a time chart showing opening / closing modes of a pressure equalizing valve and a supply valve.
FIG. 4 is a schematic configuration diagram illustrating an apparatus according to a second embodiment.
FIG. 5 is a schematic configuration diagram of an apparatus according to a third embodiment.
FIG. 6 is a schematic configuration diagram of an apparatus according to a fourth embodiment.
FIG. 7 is a schematic configuration diagram illustrating an apparatus according to a fifth embodiment.
FIG. 8 is a schematic configuration diagram of an apparatus according to a sixth embodiment.
9 is a cross-sectional view of a superconducting magnet device according to an application example of Example 6. FIG.
FIG. 10 is a time chart showing opening / closing modes of a pressure equalizing valve and a supply valve.
FIG. 11 is a schematic configuration diagram of an apparatus according to an eighth embodiment.
FIG. 12 is a schematic configuration diagram of an apparatus according to the ninth embodiment.
FIG. 13 is a schematic configuration diagram of an apparatus according to the tenth embodiment.
FIG. 14 is a schematic configuration diagram of an apparatus according to an eleventh embodiment.
FIG. 15 is a schematic configuration diagram of an apparatus according to a twelfth embodiment.
FIG. 16 is a cross-sectional view of a superconducting magnet device, showing an application example of Example 13;
FIG. 17 is a schematic configuration diagram of an apparatus according to a fourteenth embodiment.
FIG. 18 is a schematic configuration diagram of an apparatus according to a fifteenth embodiment.
[Explanation of symbols]
In the figure, 3 is a refrigerant sub tank (sub chamber), 4 is a pressure equalizing valve (pressure adjusting means, on / off valve), 4n is a pressure equalizing passage, 5 is a supply valve (open / close valve), 5n is a supply passage, and 6 and 8 are Conduit (refrigerant return passage), 10 is a refrigerant main tank (main chamber), 11 is a shield plate (cooled part), 12 is a heat source (heat source means), 13 is a backflow prevention valve, 14 is an air release valve (pressure adjusting means) ), 202 are communication pipes (small chambers), 204 and 217 are floats, and 214b is a small chamber.

Claims (6)

A main chamber in which a liquid refrigerant is stored and a gaseous refrigerant is stored on a liquid surface of the liquid refrigerant;
A subchamber in which the liquid refrigerant is stored and the gaseous refrigerant is stored on the liquid surface of the liquid refrigerant;
A refrigerant return passage that connects the main chamber and the sub chamber and includes a cooled portion in the middle, and cools the cooled portion with the liquid refrigerant fed from the sub chamber, and then returns the refrigerant to the main chamber. ,
A supply passage for supplying liquid refrigerant in the main chamber to the sub chamber;
Regulating means for regulating the flow rate of the refrigerant that is disposed in the supply passage and flows through the supply passage;
The refrigerant in the subchamber is heated, and the liquid refrigerant in the subchamber is supplied to the refrigerant return passage by the gas pressure of the gaseous refrigerant in the subchamber that is increased with the heating, and the refrigerant is passed through the refrigerant return passage. Heat source means for returning to the main room,
Pressure adjusting means capable of adjusting at least one of the gas pressure of the gaseous refrigerant in the main chamber and the gas pressure of the gaseous refrigerant in the sub chamber with respect to the other ;
The pressure adjusting means includes: a pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the sub chamber is stored; and an on-off valve that opens and closes the pressure equalizing passage. coolant supply device, characterized in that it comprises. The refrigerant supply device according to claim 1, wherein the restricting means is one of an on-off valve, a one-way valve, and an orifice. The backflow prevention valve which blocks | prevents the flow of the refrigerant | coolant from a refrigerant | coolant return path to the said subchamber is arrange | positioned in at least one of this refrigerant | coolant return path | route and this subchamber, The Claim 1 or 2 characterized by the above-mentioned. Refrigerant supply device. The auxiliary chamber has a chamber in which the liquid refrigerant in small and sub chamber volume than the sub-chamber enters the heat source means to claim 1-3, characterized by heating the coolant of the small chamber The refrigerant supply device described. The sub-chamber is equipped with a float that floats on the liquid refrigerant in the sub-chamber, and the float includes a small chamber that has a smaller volume than the sub-chamber as part of the liquid refrigerant in the sub-chamber enters. heat source means coolant supply apparatus of claim 1-4, characterized by heating the coolant of the small chamber. A main chamber in which a liquid refrigerant is stored and a gaseous refrigerant is stored on a liquid surface of the liquid refrigerant;
A sub-chamber having a first sub-chamber and a second sub-chamber, wherein the liquid refrigerant is housed and a gaseous refrigerant is housed on a liquid surface of the liquid refrigerant;
A main passage that connects the main chamber and the first sub-chamber and includes a cooled portion in the middle; a sub-passage that connects the upstream side of the cooled portion and the second sub-chamber; A refrigerant return passage for returning the refrigerant to the main chamber after cooling the cooled part with the liquid refrigerant fed from the second sub chamber;
A supply passage having a first supply passage for supplying liquid refrigerant in the main chamber to the first sub chamber, and a second supply passage for supplying liquid refrigerant in the main chamber to the second sub chamber;
A regulating means for regulating the flow rate of the refrigerant flowing through the supply passage, and having a first regulating means disposed in the first supply passage and a second regulating means disposed in the second supply passage;
Heat source means having first heat source means for heating the refrigerant in the first sub chamber and second heat source means for heating the refrigerant in the second sub chamber;
A first pressure adjusting means capable of adjusting at least one of a gas pressure of the gaseous refrigerant in the main chamber and a gas pressure of the gaseous refrigerant in the first sub chamber with respect to the other; Pressure adjusting means having second pressure adjusting means capable of adjusting at least one of the gas pressure and the gas pressure of the gaseous refrigerant in the second sub chamber with respect to the other;
A first backflow prevention valve for blocking the flow of refrigerant from the main passage of the refrigerant return passage to the first sub chamber; and a second backflow for blocking the flow of refrigerant from the sub passage of the refrigerant return passage to the second sub chamber. A backflow prevention valve having a prevention valve ,
The first pressure adjusting means includes a first pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the first sub chamber is stored, and the first pressure equalizing passage. and a first opening closed for opening and closing the passage,
The second pressure adjusting means includes: a second pressure equalizing passage that connects a space in which the gaseous refrigerant in the main chamber is stored and a space in which the gaseous refrigerant in the second sub chamber is stored; A refrigerant supply device comprising: a second on-off valve that opens and closes the passage .

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