JP2003075003A - Cryogenic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cryogenic apparatus that can be improved in maintenance efficiency and cooling efficiency. SOLUTION: A cold storage tank is attachably/detachably loaded in a cold storage tank case. The tank includes a cartridge case and a cold storage material packed in the cartridge case. The low-temperature end of a pulse pipe is connected to the cold-temperature end of the cold storage tank case through an object to be cooled. In the object, a flow passage communicating the internal space of the cold storage tank case with the internal space of the pulse pipe is formed. A gas supply device periodically repeats the supply of a refrigerant gas from the high-temperature end side of the cold storage tank case to the cold storage tank and the recovery of the gas from the cold storage tank.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a low temperature device,
In particular, it relates to a low-temperature device for cooling an object to be cooled by using a pulse tube refrigerator.

[0002]

2. Description of the Related Art FIG. 7 is a cross-sectional view of a main part of a low temperature device using a conventional pulse tube refrigerator. This low-temperature device includes a vacuum container 200, a pulse tube refrigerator 201, and an object to be cooled 250. The pulse tube refrigerator 201 includes a gas compressor 202, a high / low pressure switching valve unit 203,
A high temperature end block 204, a low temperature end block (cooling end block) 205, a regenerator 206, a pulse tube 207,
And a buffer tank 208.

In the hot end block 204, the first cavity 2
13 and a second cavity 225 are formed. The gas compressor 202 includes the valve unit 203 and the conduit connection portion 21.
It is connected to the first cavity 213 via 1. The buffer tank 208 includes the conduit connection portion 212 and the orifice 2.
It is connected to the second cavity 225 via 14.

The regenerator 206 is composed of a regenerator case 218 and a regenerator material 219 filled therein.
As the cold storage material 219, a fiber made of copper, stainless steel, or another metal or punching metal is used. Flange 216 is attached to the high temperature end of regenerator case 218 and the high temperature end of pulse tube 207. The hot end block 204 is attached to the flange 216 by bolts. The space filled with the regenerator material 219 in the regenerator case 218 communicates with the first cavity 213, and the cavity in the pulse tube 207 communicates with the second cavity 225.

A low temperature end block 205 is attached to the low temperature end of the regenerator case 218 and the low temperature end of the pulse tube 207. In the low temperature end block 205, the regenerator case 2
The space filled with the cold storage material 219 in 18 and the pulse tube 2
A gas flow path 220 is formed to communicate with the cavity inside 07.

A part of the space 221 on the regenerator 206 side of the gas flow path 220 is filled with a rectifying member 223, and a part of the space 222 on the pulse tube 207 side is filled with a rectifying member 224. . In the second cavity 225, the rectifying member 22
6 is filled. Rectifying members 223, 224 and 2
26 is made of, for example, a metal mesh or punching metal. These rectifying members rectify the flow of the refrigerant gas.

A flange 216 is provided on the wall of the vacuum container 200,
Attached with bolts or the like, the cold end block 205 is placed in a vacuum vessel. The cooling target 250 is in thermal contact with the low temperature end block 205. Cooling target 250
Are supported in the vacuum container 200 by support rods 251.

When the gas compressor 202 is operated, the supply of the refrigerant gas into the first cavity 213 and the first cavity 213 are performed.
The recovery of the refrigerant gas from is repeated. While the refrigerant gas passes through the regenerator 206, the refrigerant gas and the regenerator material 219
A heat exchange is carried out between and.

The refrigerant gas that has passed through the regenerator 206 is supplied into the pulse tube 207 through the gas passage 220.
A pressure change and a volume change occur in the refrigerant gas in the pulse tube 207. Orifice 214 and buffer tank 208
Controls the phase of pressure and volume changes. Due to a pressure change and a volume change caused by a certain phase difference, heat absorption occurs at the low temperature end block 205.

[0010]

In the conventional pulse tube refrigerator shown in FIG. 7, the regenerator material 219 is the regenerator case 218.
It is filled inside. Similarly, a part of the gas flow path 220 is filled with the rectifying members 223 and 224. A rectifying member 226 is filled in a space 225 formed in the high temperature end block 204.

When the operation of the pulse tube refrigerator is continued, impurities in the refrigerant gas, such as water and other liquids, solidify to cool the cold storage material 219 and the rectifying members 223 and 22.
4 or 226 is clogged. This allows
Cooling performance may decrease. In this case, the temperature of each part may be raised to remove the solidified liquid component.

However, in the case of impurities such as oil flowing from the gas compressor 202, it is difficult to remove the impurities even if the temperature of the relevant portion is raised. Therefore, it is necessary to replace the cold storage material 219 and the flow regulating members 223, 224, or 226.

Regenerator material 219, rectifying members 223 and 224
Alternatively, when replacing 226, the pulse tube refrigerator 20
1 needs to be removed from the object to be cooled. At this time, since the inside of the vacuum container 200 is in an atmospheric atmosphere, the object to be cooled 250 must be heated to room temperature before the pulse tube refrigerator 201 is removed. Therefore, the cooling target 250
The operation rate of low-temperature equipment including is reduced. In addition, the cooling operation is required again after the replacement with a new one, which requires enormous cost, labor and time.

Furthermore, the structure must be such that the low temperature end block 205 can be removed from the object 250 to be cooled. The removable structure leads to a reduction in heat transfer efficiency between them, and thus a reduction in cooling efficiency.

An object of the present invention is to provide a low temperature device capable of improving maintenance efficiency and cooling efficiency.

[0016]

According to one aspect of the present invention, there is provided a pulse tube having a high temperature end and a low temperature end defined therein and having a cavity therein, and a cylindrical cold storage having a high temperature end and a low temperature end defined therein. Regenerator case, a regenerator including a cartridge case and a regenerator material filled in the cartridge case, the regenerator case being removably inserted into the regenerator case, a low temperature end of the pulse tube, and the regenerator A low temperature end of the regenerator case, a cooling object having a flow passage formed therein to connect the space in the regenerator case and the space in the pulse tube to each other, and the high temperature end of the regenerator case. Provided is a low-temperature device having a gas supply device that periodically repeats supply of the refrigerant gas into the regenerator and recovery of the refrigerant gas from the regenerator from the side.

The cartridge type regenerator can be replaced with the object to be cooled attached to the low temperature end of the regenerator case. In addition, since the flow path is formed in the cooling target, the cooling target can be efficiently cooled compared to the case where the flow path and the cooling target are detachably coupled to each other. .

[0018]

1 is a cross-sectional view of a cryogenic device according to a first embodiment of the present invention. The cryogenic device according to the first embodiment includes a pulse tube refrigerator 30, a vacuum container 100, and a heat shield plate 101.

A hole for attaching the pulse tube refrigerator 30 is formed in a part of the wall of the vacuum container 100. The high temperature end block 4 is detachably attached to the outer surface of the wall of the vacuum container 100 with a bolt or the like to close the hole. A first cavity 13 and a second cavity 25 are formed in the high temperature end block 4. The gas compressor 2 is connected to the first cavity 13 via the high pressure / low pressure switching valve unit 3 and the pipe line connecting portion 11. Buffer tank 15
Are connected to the second cavity 25 via the conduit connection 12 and the orifice 14.

The high temperature end of the regenerator case 18 and the high temperature end of the pulse tube 7 are attached to the inner surface of the vacuum container 100 by brazing or the like. The space inside the regenerator case 18 communicates with the first cavity 13 in the high temperature end block 4 through a hole formed in the wall of the vacuum container 100. The cavity inside the pulse tube 7 communicates with the second cavity 25 through a hole formed in the wall of the vacuum container 100. The regenerator case 18 and the pulse tube 7 both have a cylindrical shape and are arranged in parallel with each other.

Low temperature end of regenerator case 18 and pulse tube 7
The heat shield plate 101 is attached to the low temperature end of the device by brazing or the like. Inside the heat shield plate 101, there is provided a gas flow path 20 that connects the space inside the regenerator case 18 and the cavity inside the pulse tube 7. The heat shield plate 1
A part of 01 may be made thick and the gas passage 20 may be formed in this portion, or the metal member having the gas passage 20 and the heat shield plate may be fixed so that they cannot be removed from each other. Good.

A cartridge type rectifier 32 is loaded in a partial space 21 on the regenerator case 18 side of the gas flow path 20, and a cartridge type rectifier 33 is loaded in a partial space 22 on the pulse tube 7 side. Has been done. The rectifier 32 includes a cartridge case 38 and a rectifying member 23. The cartridge case 38 is in close contact with the inner surface of the gas flow path 20.
The rectifying member 23 is filled in the cartridge case 38. Like the rectifier 32, the rectifier 33 includes the cartridge case 39 and the rectifying member 24.

A cartridge type regenerator 31 is loaded in the regenerator case 18. The regenerator 31 is composed of a cartridge case 35 and a regenerator material 19. The cartridge case 35 has a cylindrical shape, and the outer peripheral surface thereof is in close contact with the inner peripheral surface of the regenerator case 18. The cool storage material 19 is filled in the cartridge case 35. The cartridge case 35 is made of bakelite, plastic, stainless steel, or the like, which has a low thermal conductivity. Thereby, a temperature difference easily occurs between the end of the cartridge case 35 on the high temperature end block 4 side and the end of the cartridge case 35 on the low temperature end block 5 side.

Regenerator case 18 and cartridge case 3
An O-ring 37 is arranged in the vicinity of the high temperature end between the O-ring 37. The O-ring 37 prevents the refrigerant gas from entering between the regenerator case 18 and the cartridge case 35.

A cartridge type rectifier 51 is loaded in the first cavity 13 in the high temperature end block 4, and a cartridge type rectifier 34 is loaded in the second space 25. The rectifier 51 includes a cartridge case 52 and a rectifying member 53, and the rectifier 34 includes a cartridge case 40 and a rectifying member 26.
Its structure is similar to that of the rectifier 32. The cartridge cases 38, 39, 40 and 52 are made of copper or another metal material having high thermal conductivity.

O is provided between the outer peripheral surface of the cartridge case 52 and the inner peripheral surface of the hole of the vacuum container 100, and between the end of the cartridge case 35 of the regenerator 31 and the high temperature end block 4.
A ring 36 is arranged. Cartridge case 40
O-ring 4 between the end surface of the container and the outer surface of the vacuum container 100.
1 is arranged, the cartridge case 40 and the second space 2
The O-ring 42 is disposed between the O-ring 42 and the No. 5. O-ring 3
6, 41 and 42 prevent the refrigerant gas from leaking from the inside of the pulse tube refrigerator 30.

When the high temperature end block 4 is removed from the vacuum container 100, the cartridge type rectifiers 51 and 34 can be easily replaced. Also, the regenerator 31 can be easily replaced. The rectifier 32 is the regenerator case 1
It can be easily replaced through the space inside. The cartridge case 35 of the regenerator 31 and the cartridge case 38 of the rectifier 32 may be integrated. Further, the cartridge cases 35 and 38 may be integrated with the cartridge case 52 of the rectifier 51. The rectifier 33 can be easily replaced through the cavity in the pulse tube 7.

Further, the regenerator 31, the rectifiers 32, 33, 34, and 51 can be exchanged while the inside of the vacuum container 100 is kept in vacuum. Therefore, the pulse tube refrigerator 30 can be maintained without raising the temperature of the heat shield plate 101, which is the cooling target, to room temperature.

Further, in the low temperature apparatus according to the first embodiment, the gas flow path 20 connecting the low temperature ends of the regenerator 31 and the pulse tube 7 is the heat shield plate 10 which is the object to be cooled.
It is formed directly in the inside 1. Therefore, the cold generated at the low temperature end is directly transmitted to the heat shield plate 101. Thereby, the heat transfer efficiency can be improved.

Further, in the first embodiment, the regenerator case 18 and the pulse tube 7 physically support the heat shield plate 101 inside the vacuum container 100. Pulse tube refrigerator 3
Since it is not necessary to remove the regenerator case 18 and the pulse tube 7 even during maintenance of 0, the heat shield plate 101
It is not necessary to arrange another supporting member for mechanically supporting the. For this reason, it is possible to suppress the invasion of heat via the support member.

Next, with reference to FIG. 2, a low temperature device according to a second embodiment of the present invention will be described.

FIG. 2 shows a cross section of a cryogenic device according to a second embodiment. In the low temperature device according to the second embodiment, a two-stage pulse tube refrigerator 70 is used.

The pulse tube refrigerator 70 is similar to the pulse tube refrigerator 30 shown in FIG. 1 in that the pipe line connecting portions 11 and 12, the orifice 14, the buffer tank 15, the pulse tube 7, which are provided in the high temperature end block 4, are provided. The regenerator case 18, the heat shield plate 101, the regenerator 31, the rectifiers 33, 34 and 51, and the rectifying member 23 are included. The cartridge case 38 of the rectifier 32 shown in FIG. 1 is integrated with the cartridge case 35 of the regenerator 31.

A second-stage regenerator case 81 is arranged on an extension of the central axis of the first-stage regenerator case 18. The regenerator case of the second stage is attached to the heat shield plate 101 at its high temperature end by brazing or the like. The space in the second-stage regenerator case 81 communicates with the space in the first-stage regenerator 31 via the gas passage 20 formed in the heat shield plate 101.

The second-stage pulse tube 72 is parallel to the first-stage regenerator case 18 and the second-stage regenerator case 81.
Are arranged. The high temperature end of the second-stage pulse tube 72 is attached to the inner surface of the vacuum container 100.
As in the case of the pulse tube 7 of the first stage, the cavity in the pulse tube 72 of the second stage has the third space 90, the orifice 76, and the pipe line connecting portion 75 formed in the high-temperature end block 4. Through to the buffer tank 77. Third space 9
A cartridge-type rectifier 74 is installed in the 0. The rectifier 74 includes a cartridge case 91 and a rectifying member 92 filled in the cartridge case 91.

The condensing vessel 110 connects the low temperature end of the second stage regenerator case 81 and the low temperature end of the second stage pulse tube 72. In the condensing container 110, a gas flow path 111 that connects the space inside the second-stage regenerator case 81 and the space inside the second-stage pulse tube 72 is provided. The regenerator 71 of the second stage is loaded in the regenerator case 81 of the second stage. The second-stage regenerator 71 includes a cartridge case 82 and a second-stage regenerator material 83 filled therein.
It is configured to include. Further, both ends of the cold storage material 83 are filled with rectifying members 84 and 85, respectively.

Second stage pulse tube 72 of gas flow path 111
A cartridge type rectifier 73 is loaded in a part of the space on the side. The cartridge type rectifier 73 includes a cartridge case 88 and a rectifying member 89.

In the condensing container 110, a condensing cavity 11 is further provided.
Two are provided. A liquefied helium tank 115 is attached to the condensation container 110 via two pipe lines 113 and 114. Each of the pipelines 113 and 114 connects the cavity in the liquefied helium tank 115 to the condensation cavity 112.

When the pulse tube refrigerator 70 is operated, the heat shield plate 101 and the condensation container 110 are cooled. Since the gas flow path 20 is formed directly in the heat shield plate 101, the heat shield plate 101 can be efficiently cooled. Since the gas flow passage 111 and the condensing cavity 112 are provided in one condensing container 110, the condensing cavity 112 can be efficiently cooled.

When the liquefied helium 116 stored in the liquefied helium tank 115 evaporates, it penetrates into the condensing cavity 112 through the pipe line 113. The liquefied helium cooled in the condensing cavity 112 and re-condensed is recovered in the liquefied helium tank 115 through the pipe line 114.

When the high temperature end block 4 is removed from the vacuum container 100, the rectifiers 34, 51, 74 and the regenerator 31 can be easily replaced. In addition, the second-stage regenerator 71 can be easily replaced through the space inside the first-stage regenerator case 18. The rectifier 33 can be easily replaced through the space inside the first-stage pulse tube 7, and the rectifier 73 can be easily replaced through the space inside the second-stage pulse tube 72.

Even if the high temperature end block 4 is removed, since the vacuum inside the vacuum container 100 is maintained, the condensing container 11
The maintenance of the pulse tube refrigerator 70 can be performed without raising the temperature of the liquid crystal helium tank 115 and the liquefied helium tank 115.

In the first and second embodiments, the case where the object to be cooled is the heat shield plate or the condensing container for recondensing the liquefied helium has been described. The pulse tube refrigerator used in the low temperature apparatus according to the above embodiment can be used for cooling other objects to be cooled. Hereinafter, with reference to FIGS. 3 to 6, third to sixth embodiments for cooling other objects to be cooled by the pulse tube refrigerator will be described.

FIG. 3 is a schematic view of a low temperature device (cryopump) according to the third embodiment. The pulse tube refrigerator 70 used is the same as that used in the low temperature device according to the second embodiment shown in FIG. Less than,
The description will be continued by focusing on the points different from the low temperature device according to the second embodiment.

The pulse tube refrigerator 70 is attached to the vacuum container 100 as in the case of the second embodiment. A baffle plate 120 is attached to a part of the heat shield plate 101. A cryopanel 121 is attached to the low temperature ends of the second-stage regenerator case 81 and the second-stage pulse tube 72. In the cryopanel 121, the space inside the second-stage regenerator case 81 and the second-stage pulse tube 72
A gas flow path 111 is formed to communicate with the inner cavity. Activated carbon 122 is fixed to the cryopanel 121.

Also in the case of the third embodiment, the heat shield plate 1
01, the baffle plate 120, and the cryopanel 121 can be cooled efficiently. Further, the pulse tube refrigerator 70 can be maintained without raising the temperature of the cryopanel 121.

FIG. 4 shows a sectional view of a low temperature device (superconducting coil) according to the fourth embodiment. A superconducting coil 131 is wound around the coil bobbin 130. Pulse tube refrigerator 70
Second-stage regenerator case 81 and second-stage pulse tube 7
The cold end of 2 is attached to the coil bobbin 130. In the coil bobbin 130, a gas flow path 111 that connects the space inside the second-stage regenerator case 81 and the cavity inside the second-stage pulse tube 72 is formed. The pulse tube refrigerator 70 is similar to the pulse tube refrigerator used in the low temperature device according to the second embodiment shown in FIG.

FIG. 5 shows a sectional view of a low temperature apparatus (liquefied gas tank) according to the fifth embodiment. Second of the pulse tube refrigerator 70
The low temperature ends of the regenerator case 81 of the second stage and the pulse tube 72 of the second stage are attached to the liquefied gas tank 140. In the wall of the liquefied gas tank 140, the second-stage regenerator case 81
A gas flow path 111 is formed to connect the internal space and the cavity in the second-stage pulse tube 72. Liquefied gas tank 14
The inside of 0 is filled with the liquefied gas 141. Examples of the liquefied gas include helium, neon, nitrogen, oxygen, hydrogen and the like.

FIG. 6 is a sectional view of a low temperature device (wafer chuck) according to the sixth embodiment. The regenerator case 18 of the pulse tube refrigerator 30 and the low temperature end of the pulse tube 7 are attached to the lower surface of the wafer chuck 150. In the wafer chuck 150, the space inside the regenerator case 18 and the pulse tube 7
A gas flow path 20 is formed to communicate with the inner cavity. The pulse tube refrigerator 30 is similar to the pulse tube refrigerator used in the low temperature device according to the first embodiment shown in FIG.

A semiconductor wafer 155 is placed on the upper surface of the wafer chuck 150. A plurality of vacuum suction ports 151 are opened on the mounting surface of the semiconductor wafer 155. The vacuum suction port 151 is connected to the exhaust flow path 152.
The semiconductor wafer 155 is fixed to the upper surface of the wafer chuck 150 by exhausting the inside of the exhaust flow path 152 with a vacuum pump. The surface on which the semiconductor wafer 155 is placed and the gas passage 20 are configured so that they cannot be removed from each other.

Also in the case of the fourth to sixth embodiments, the object to be cooled can be efficiently cooled. Further, the pulse tube refrigerator can be maintained without raising the temperature of the object to be cooled.

The present invention has been described above with reference to the embodiments.
The present invention is not limited to these. For example, it will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

[0053]

As described above, according to the present invention,
Since the low temperature end of the pulse tube refrigerator and the object to be cooled are inseparable, the object to be cooled can be efficiently cooled. Moreover, since the regenerator and the rectifier are of a cartridge type, the regenerator and the rectifier can be replaced while maintaining the vacuum in which the object to be cooled is arranged.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a low temperature device according to a first embodiment.

FIG. 2 is a sectional view of a cryogenic device according to a second embodiment.

FIG. 3 is a sectional view of a cryogenic device according to a third embodiment.

FIG. 4 is a partial sectional view of a low temperature device according to a fourth embodiment.

FIG. 5 is a partial cross-sectional view of a cryogenic device according to a fifth embodiment.

FIG. 6 is a partial sectional view of a low temperature device according to a sixth embodiment.

FIG. 7 is a cross-sectional view of a conventional low temperature device.

[Explanation of symbols]

2 gas compressor 3 High pressure / low pressure switching valve 4 High temperature end block 7 First stage pulse tube 15,77 buffer tank 18 First-stage regenerator case 20 gas flow paths 30, 70 Pulse tube refrigerator 31 First stage regenerator 32, 33, 34, 51, 73, 74 Rectifier 71 Second stage regenerator 72 Second stage pulse tube 81 Second-stage regenerator case 100 vacuum vessels 101 heat shield plate 110 Condensation container 115 Liquefied gas tank 120 baffle board 121 Cryopanel 122 activated carbon 130 coil bobbin 131 Superconducting coil 140 liquefied gas tank 141 Liquefied gas 150 wafer chuck 151 Vacuum suction port 152 Exhaust channel 155 Semiconductor wafer

Claims (9)

[Claims] 1. A pulse tube having a high temperature end and a low temperature end defined therein and having a cavity therein, a tubular regenerator case having a high temperature end and a low temperature end defined therein, a cartridge case and a cartridge case in the cartridge case. A regenerator, which includes a filled regenerator material and in which the cartridge case is detachably inserted into the regenerator case, connects the low temperature end of the pulse tube and the low temperature end of the regenerator case, and A space in the cooler case, a cooling object having a flow path formed therein to connect the space in the pulse tube to each other, and from the high temperature end side of the regenerator case, of the refrigerant gas into the regenerator. A low-temperature device having a gas supply device that periodically repeats supply and recovery of the refrigerant gas from the inside of the regenerator. 2. The object to be cooled includes a heat shield plate,
The cryogenic apparatus according to claim 1, wherein the portion defining the flow path and the heat shield plate are integrally molded or fixed so as not to be mutually removable. 3. The object to be cooled has a condensing cavity defined therein, and the flow path and the condensing cavity are configured so as not to be removable from each other. Further, a low temperature containing a low temperature liquefied gas is contained. 2. A tank, and a passage for connecting a cavity in the low temperature tank and the recondensation cavity to allow a gas or a liquefied gas to flow therethrough.
Low temperature device described in. 4. The object to be cooled includes a cryopanel of a cryopump, and the portion defining the flow path and the cryopanel are integrally molded or fixed so as not to be mutually removable. The low temperature device according to 1. 5. The object to be cooled includes a superconducting coil bobbin, and the portion defining the flow path and the superconducting coil bobbin are integrally molded or fixed so that they cannot be removed from each other. The low temperature apparatus according to claim 1. 6. The method according to claim 1, wherein the object to be cooled includes a cryostat, and the portion defining the flow path and the cryostat are integrally molded or fixed so as not to be mutually removable. Low temperature device. 7. The object to be cooled has a mounting surface on which a holding object is mounted, and the flow path and the mounting surface are not removable from each other. The cryogenic apparatus according to claim 1, further comprising a fixing mechanism that fixes a holding object placed on the surface. 8. The vacuum object further includes a vacuum container in which the object to be cooled is arranged, and the object to be cooled is physically supported in the vacuum container by the pulse tube and the regenerator case. Item 7. A low temperature device according to any one of items 1 to 7. 9. A cylindrical second regenerator case, which is inserted between the regenerator case and the gas supply device and defines a refrigerant gas transportation path therebetween, and a second cartridge. A second regenerator material is filled in the case and the second cartridge case, and the second cartridge case is removably inserted in the transportation path defined by the second regenerator case. A second regenerator, a gas flow path branched from a portion where the regenerator case and the second regenerator case are connected, a high temperature end and a low temperature end are defined, and a low temperature end is the gas flow path. 9. A cryogenic device according to any one of claims 1 to 8 having a second pulse tube connected to the.