JP2001304711A - Cryogenic cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance reliability of a refrigerating machine (R) or a cooling system (S) by efficiently cooling a compressor (4), in the case the cryogenic cooling system (S) for cooling a cooling object matter (2) to a set temperature set to a cryogenic temperature by a Stirling type pulse pipe refrigerating machine having a pulse pipe (14) is housed in a casing (1). SOLUTION: A cold accumulator (9) and the pulse pipe (14) of the pulse pipe refrigerating machine (R) and the cooling object matter (2) are housed in the casing (1), and the compressor (4) and the high temperature sections (38), i.e., an inertance pipe (17) and a buffer part (19), are disposed outside of the casing (1) and the compressor (4). Inertance pipe (17) and the buffer part (19) disposed outside of the casing (1) are forcibly cooled by a cooling fan (33). Energy efficiency is enhanced by performing cooling with the compressor (4), the inertance pipe (17) and the buffer part (19) at temperatures lower than those in the case of those housed in the casing (1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cryogenic cooling system for cooling an object to be cooled by generating refrigeration by a cryogenic refrigerator, and more particularly to a technical field for improving the reliability thereof.

[0002]

2. Description of the Related Art Heretofore, as this kind of cryogenic cooling system, a system provided with a free displacer type Stirling refrigerator has been known. This free displacer type Stirling refrigerator is a kind of a cryogenic refrigerator that generates a cryogenic level of cold.
As shown in Japanese Patent No. 39510, etc., a compressor for compressing a working gas and an expander for expanding a working gas discharged from the compressor are combined. The compressor is
A cylinder disposed in a closed casing, a piston reciprocally fitted into the cylinder and defining a compression space in the cylinder space, and a linear motor as a drive source for reciprocating the piston. A piston spring that elastically supports the piston in a reciprocating manner on the casing, and by applying an alternating current of a predetermined frequency to a drive coil (drive coil) of the linear motor, the piston is reciprocated in the cylinder to compress the space. Generates a gas pressure in a predetermined cycle.

On the other hand, the expander is fitted with a cylinder, a free displacer which is reciprocally fitted in the cylinder, and divides a space in the cylinder into an expansion space and a working space. A displacer spring for elastic support; a regenerator (regenerative heat exchanger) filled with regenerator material is provided in the free displacer; the working space is connected to the compression space of the compressor; By causing the free displacer to reciprocate and expand the working gas in the expansion space by the working gas pressure from the chiller, cold is generated in the cold head at the tip of the cylinder. Has become.

By the way, conventionally, an infrared surveillance camera using a superconducting material which normally operates under a cryogenic temperature condition is known, and this surveillance camera uses a cryogenic cooling system having a refrigerator. Therefore, it is necessary to keep the cooling at the cryogenic level.

When such an infrared surveillance camera is cooled for outdoor use by a cryogenic cooling system, the infrared surveillance camera, various other electrical components, and a control device are all-in-one type together with a refrigerator and a power supply for driving the same in a housing. Is stored. Further, in order to adapt to all weather without the influence of rain or wind, it is necessary to perform a treatment such as waterproofing or rustproofing.

[0006]

However, in such a cryogenic cooling system, it has been difficult to operate the refrigerator for a long time. That is, since the cooling system is used outdoors together with the infrared surveillance camera, the environmental temperature of the cooling system rises to about 70 ° C. in summer and high temperature conditions, but drops to about −20 ° C. in winter and cold regions. Since the casing of the cooling system is completely sealed as described above, the compressor and electrical components housed therein serve as a heating element, and the temperature inside the casing is higher than the ambient temperature by +2.
0 to + 30 ° C is higher. For this reason, there is no problem in winter or cold regions, but in summer or high temperature conditions, compressors and electrical components are exposed to high temperatures, and their operation and life may be greatly affected, leading to abnormal conditions. There is.

Therefore, it is conceivable to provide a cooling fan in the housing and circulate air in the housing by the fan to forcibly cool the housing. However, the cooling effect of the fan is small and the effectiveness is low inside the completely sealed housing.

The present invention has been made in view of the above points, and a main object of the present invention is to improve a cryogenic cooling system using a cryogenic refrigerator, thereby efficiently cooling the compressor to achieve refrigeration. To improve the reliability of the machine or cooling system.

[0009]

In order to achieve the above object, according to the present invention, of the cryogenic refrigerators, the compressor as a heating element is arranged outside the housing under the same condition as the environmental temperature. Thus, the compressor was forcibly cooled outside the housing.

More specifically, according to the first aspect of the present invention, a compressor (4) for compressing the working gas, and the working gas compressed by the compressor (4) is expanded to generate cryogenic temperature. A cryogenic refrigerator (R) comprising cold generating means (8) and (35) for cooling the cooled object (2) to a cryogenic level set temperature. At least the cryogenic portion (15) and the object to be cooled (2) of the cold generating means (8) and (35) are accommodated in the housing (1). Further, the compressor (4) is disposed outside the housing (1), and a cooling means (33) for forcibly cooling the compressor (4) is provided.

According to the above configuration, the compressor (4) is disposed outside the housing (1) and is forcibly cooled by the cooling means (33). As a result, the compressor (4) can be cooled at a lower temperature than the case where the compressor is housed inside the housing, and the compression efficiency of the compressor (4) is increased by increasing the cooling efficiency. The performance and life of the refrigerator (4) can be improved, and the reliability of the refrigerator (R) or the cooling system can be improved.

According to the second aspect of the present invention, the cryogenic refrigerator (R) has a compressor (4) at one end through a regenerator (9).
And a pulse tube (14) connected to the pulse tube (1).
Cold generation means (8) having a buffer section (19) connected to the other end of 4) via an inertance pipe (17).
And a pulse tube refrigerator equipped with Then, the inertance pipe (17) and the buffer section (19) are arranged outside the housing (1).

With this arrangement, the inertance tube (17) and the buffer section (19), which are the high temperature section of the pulse tube refrigerator forming the cryogenic refrigerator (R), can be efficiently cooled outside the housing (1). Accordingly, the performance of the refrigerator (R) can be improved and the power consumption of the cooling system can be reduced.

According to a third aspect of the present invention, a cryogenic refrigerator (R)
Is a displacer type expander (3
A Stirling refrigerator equipped with 5). And the high temperature part (38) of the said expander (35) is arrange | positioned outside the housing (1). As a result, the high temperature section (38) of the expander (35) of the Stirling refrigerator, which is a cryogenic refrigerator (R),
Can be efficiently cooled outside the housing (1), the performance of the refrigerator (R) can be improved, and the power consumption of the cooling system can be reduced.

According to the fourth aspect of the present invention, at least the cryogenic portion (1) of the cold generating means (8), (35) is provided in the housing (1).
5) and the object to be cooled (2) are inserted from the opening (21) to provide a vacuum chamber (23) in which the vacuum chamber (23) is housed in a vacuum-insulated state. It is structured to be closed by a lid (12) that is a part of the housing (1).

According to this structure, the vacuum chamber (23)
Since the lid (12) for closing the housing forms a part of the housing (1), the cooling system can be reduced in size and weight by using the lid (12) and the wall of the housing (1). Can be.

[0017]

(Embodiment 1) FIG. 1 shows the entire configuration of a cryogenic cooling system (S) according to Embodiment 1 of the present invention. It is used for cooling sensor of camera.

In FIG. 1, (1) is a rectangular sealed housing, which normally operates inside the housing (1) while being cooled and maintained at a cryogenic level set temperature. A cooled body (2) made of the above-mentioned sensor or the like containing a high-temperature superconducting material and various electric components (not shown) are housed therein.

(R) is a cryogenic refrigerator composed of a Stirling type pulse tube refrigerator for applying cold to the object to be cooled (2) and keeping the temperature at the cryogenic level. The configuration of the refrigerator (R) will be described with reference to FIG. 4. The refrigerator (R) includes a known double-piston compressor (4). That is, the compressor (4) has a closed casing (5). Although not shown, a cylindrical cylinder is disposed in the casing (5), and a pair of opposed cylinders is disposed in the cylinder. The pistons reciprocate and are fitted so as to be able to approach and separate from each other, a compression space is defined between the two pistons, and a working gas such as helium is filled. Each piston is elastically supported reciprocally via a piston spring with respect to the casing (5), and a linear motor is drive-coupled to each piston.
By supplying alternating current synchronously to the drive coils of both linear motors, both pistons are reciprocated synchronously in opposite directions so as to approach and separate from each other at a predetermined operating frequency, and change in a compression space at a predetermined cycle. It is adapted to generate gas pressure. (6) radiating fins protruding around a portion corresponding to the compression space in the casing (5) of the compressor (4) and radiating the working gas compressed in the compression space.

One end of a connecting pipe (7) is connected to the compression space of the compressor (4), and the other end of the connecting pipe (7) is connected to a cold generating section (8). The cold generating section (8) includes a regenerator (9) (regeneration heat exchanger) having one end (lower end) connected to the other end of the connection pipe (7). The regenerator (9) is formed by filling a regenerator (not shown) made of a metal mesh or the like into a vertically extending tubular body (10) having both ends opened. 10) is a cylindrical body (10) on a lid (12) made of a disc.
The lower end of the cylindrical body (10) is erected on the upper surface of the lid (12) in an air-tight manner and integrated with the upper surface of the lid (12).
It communicates with the connection pipe (7) through a communication passage (not shown) penetrating through 2). When the working gas is recovered in the compression space, the cold of the working gas is stored in the cold storage material of the cool storage (9) by heat exchange,
Conversely, when the working gas is supplied from the compression space to the pulse tube (14) due to an increase in the gas pressure in the compression space, the working gas is given a cold stored in the cold storage material by heat exchange.

On the side of the regenerator (9), a pulse tube (14) extending in the vertical direction in parallel with the regenerator (9) is arranged. This pulse tube (14) is a regenerator (9)
A tubular member having a predetermined inner diameter substantially the same length as the cylindrical body (10) and having a smaller inner diameter than the cylindrical body (10), and the lower end thereof is integrally joined to the disc-shaped lid (12) in an airtight manner. It stands upright.

The cylinder (10) of the regenerator (9)
A cold head (15) as a cryogenic part made of a material having high thermal conductivity is bridged between the upper end and the upper end of the pulse tube (14).
The upper ends of the regenerator (9) and the pulse tube (14) are connected and fixed integrally by 5), and the cold body (2) is brought into contact with the cold head (15) so as to transfer heat. are doing. Inside the cold head (15), there is a cylinder (1).
An expansion space (not shown) that communicates the inside of the pulse tube (14) with the inside of the pulse tube (14) is formed through.

The lid (12) below the pulse tube (14)
One end of an inertance tube (17) made of a thin tube having a predetermined inner diameter is attached and fixed to the lower surface, and the inside of the inertance tube (17) is formed to penetrate the lower end of the pulse tube (14) and the lid (12). The communication is made through a communication path (not shown). The other end of the inertance pipe (17) is connected to a sealed buffer space (not shown) in the buffer section (19), and the phase of the working gas pressure is controlled by the inertance pipe (17). A virtual piston is formed by the working gas in the pulse tube (14), and the virtual piston is reciprocated in the pulse tube (14) by the gas pressure from the compressor (4) to transfer the working gas to the cold head ( By causing the cold head (15) to expand at the extremely low temperature level by expanding in the expansion space in the 15), the cold body (2) is cooled and held at the same extremely low level setting temperature by the cold. It has been made to be.

As a feature of the present invention, the regenerator (9), the pulse tube (14), the cold head (15) and the object to be cooled (2) are housed inside the housing (1).
The compressor (4) is arranged outside the housing (1). That is, as shown in FIG. 3, an opening (21) formed of a circular hole having a diameter smaller than that of the lid (12) is formed through the bottom wall of the housing (1), and the opening (21) is formed. On the upper surface of the surrounding bottom wall, a bottomed cylindrical vacuum chamber (23) whose upper end is closed is protrudingly provided so as to be located in the housing (1). Thus, the vacuum chamber (23) is formed integrally with the bottom wall of the housing (1). In the vacuum chamber (23), the regenerator (9) and the pulse tube (1) are placed.
4) the cold head (15) and the object to be cooled (2) are fitted through the opening (21) and housed in a vacuum insulated state;
The cylinder (10) and the pulse tube (14) of the regenerator (9)
The cover (12) having the lower ends fixedly supported by the bolts (25) and the nuts (26) is fixed to the lower surface of the bottom wall around the opening (21) as a part of the housing (1) by fastening. The opening (21) is hermetically closed by the lid (12) so that the vacuum chamber (23) is sealed.

The compressor (4) is disposed below the housing (1). The compressor (4) is provided with a bracket (27) protruding from the front end of the lower surface of the bottom wall of the housing (1). ) Compressor heat dissipation block (31), (31)
Is fixedly supported. Therefore, the compressor (4) is arranged outside the housing (1).

Further, the inertance pipe (17) and the buffer section (19) are also arranged outside the housing (1). The inertance pipe (17) extends to the rear side of the compressor (4) after hanging from the lid (12) of the bottom wall of the housing (1), and as shown in FIG. ) They are arranged together in the rear space. On the other hand, the buffer section (19) is arranged below the center of the compressor (4).

As shown in FIGS. 2 and 3, a radiation fin (30) for dissipating heat of electric components and the like in the housing (1) is integrally attached to a front surface of the housing (1). I have. The radiating fins (30) on the front surface of the housing (1) extend from the lower end of the front surface of the housing (1) to the front side of the compressor (4). ) Are located at both ends of the heat dissipation block (3).
The contact is made so as to be able to conduct heat via 1), and the heat generated by the casing (5) of the compressor (4) is radiated by the radiating fins (30).

In the compressor (4), the center of the casing (5) in the left and right direction (radiation fins (6), (6),
..), A cooling fan (33) is disposed as cooling means for forcibly cooling the compressor (4). The cooling fan (33) cuts out a part of the radiating fin (30) on the front surface of the housing (1) and is housed and fixed in the notch. The compressor (4) to the inertance pipe (1).
7) and the buffer section (19) are forcibly cooled (the flow of air from the cooling fan (33) is indicated by arrows in FIGS. 1 and 2).

Next, the operation of the cryogenic cooling system (S) of the above embodiment will be described. When the refrigerator (R) is operated, alternating current of a predetermined frequency is synchronously energized to drive coils of both linear motors of the compressor (4) disposed outside the housing (1). With this energization, both pistons reciprocate in the opposite direction in synchronization with each other so as to move toward and away from the neutral position, and the volume of the compression space increases and decreases due to the contact and separation of both pistons. A periodic pressure wave is generated. One end of a pulse tube (14) is connected to this compression space via a connecting tube (7), a regenerator (9) and a cold head (15), and the other end of the pulse tube (14) is connected to an inertance tube ( Since the buffer section (19) is connected via the (17), the phase of the working gas pressure is controlled by the inertance pipe (17), and a virtual piston is formed in the pulse pipe (14) by the working gas. , This virtual piston is driven by the gas pressure from the compressor (4) to generate a pulse tube (1).
In 4), the working gas reciprocates in the same cycle as the pressure wave in the compression space (11), and expands in the expansion space in the cold head (15). ) Is cooled to the cryogenic level, and the object to be cooled (2) arranged to be able to conduct heat to the cold head (15) is maintained at the same cryogenic level set temperature.

At this time, the cooling fan (33) located in front of the compressor (4) operates, and this cooling fan (3)
By the operation of 3), air is sent to the radiation fins (6), (6),... Around the casing (5) of the compressor (4) to cool the compressor (4). Thus, the compressor (4)
Is arranged outside the housing (1) and is forcibly cooled by air from the cooling fan (33), so that the compressor (4) is cooled under the same conditions as the environmental temperature outside the housing (1). The Rukoto. Therefore, the compressor (4) can be cooled at a lower temperature as compared with the case where the same compressor is housed inside the housing and cooled by the cooling fan provided therein, and the compressor (4) is cooled. Compressor with increased efficiency (4)
Of the refrigerator (R) and thus the cooling system (S) can be improved in reliability and performance.

Further, only the regenerator (9), the pulse tube (14) and the cold head (15) of the cryogenic refrigerator (R) (pulse tube refrigerator) are accommodated in the housing (1), and the inertance tube is provided. (17) and the buffer section (19) are also arranged outside the housing (1), and these are the compressor (4).
Is cooled by the blowing air of the cooling fan (33), so that the inertance pipe (17) and the buffer section (1).
9) can be efficiently cooled outside the housing (1), and accordingly, the performance of the cryogenic refrigerator (R) can be further improved, and the power consumption of the cooling system (S) can be reduced. .

Further, a vacuum chamber (2) is provided in the housing (1).
3) is provided, and a regenerator (9) and a pulse tube (1) of the cryogenic refrigerator (R) are provided in the vacuum chamber (23).
4) Cold head (15) and object to be cooled (2)
, The regenerator (9), the pulse tube (14), the cold head (15), and the object to be cooled (2)
Is thermally insulated in a vacuum, heat intrusion from the outside is suppressed, and the performance of the refrigerator (R) and the object to be cooled (2) is well maintained.
Then, the regenerator (9), the pulse tube (14), the cold head (15) and the object to be cooled (2) are accommodated by being inserted from the opening (21) of the bottom wall of the housing (1). Since the portion (21) is closed by the lid (12) which is a part of the housing (1), the lid (12) and the housing (1) are closed.
The cooling system (S) can be reduced in size and weight by being shared with the wall.

(Embodiment 2) FIG. 5 shows Embodiment 2 (note that the same parts as those in FIGS. 1 to 4 are denoted by the same reference numerals and detailed description thereof is omitted).
A pulse tube refrigerator is used as the cryogenic refrigerator (R), but a Stirling refrigerator equipped with a displacer type expander is used.

That is, in this embodiment, the compressor (4) of the cryogenic refrigerator (R) is a double piston type compressor similar to that of the first embodiment, and a connecting pipe (7) is connected to the compressor (4). ) Is connected to a displacer type expander (35) as a cold generation means.

The expander (35) has a vertically extending cylindrical cylinder (36), and the opening at the tip (upper end) of the cylinder (36) is formed by a cold head (15), which is a cryogenic part. The openings on the base end side (the lower end side) are closed by flange portions (37), and the object to be cooled (2) is in heat contact with the cold head (15). Although not shown, a hollow cylindrical free displacer that partitions the internal space into an expansion space on the distal end side (cold head (15) side) and a working space on the proximal end side is reciprocally movable in the cylinder (36). The cool storage material is housed in the inner space of the displacer. The cold storage material is communicated with the expansion space and the working space through communication holes at both ends of the displacer. The base end of the displacer is resiliently supported on the flange portion (37) via a displacer spring facing the working space so as to reciprocate.

The working space of the expander (35) is connected to the compression space of the compressor (4) through a gas hole (not shown) formed through the flange (33) and the connecting pipe (7). And the expander (3) is operated by the gas pressure from the compressor (4).
By causing the displacer of 5) to reciprocate in the cylinder (36) to expand the working gas in the expansion space, the cold head (15) generates cryogenic-level cold,
Due to the cold, the object to be cooled (2) is cooled and maintained at a similar cryogenic level.

A portion of the cylinder (36) of the expander (35) around the working space is a high-temperature portion (38), and the high-temperature portion (38) of the cylinder (36) has an operating portion in the working space. Radiation fins (41), (4) for cooling gas
1), ... are protrudingly provided.

Then, in the cylinder (36) of the expander (35), the high-temperature portion (3) around the working space (36).
8) A lid (12) is integrally provided at the upper end (boundary portion between the high-temperature portion (38) and other portions), and in the expander (35), the high-temperature portion of the cylinder (36) is provided. (38) is arranged outside the housing (1), and the high-temperature part (3
The cylinder (36) other than 8) is housed in the vacuum chamber (23) together with the cooled object (2), and the cylinder (36) and the cooled object (2) are moved by the vacuum in the vacuum chamber (23). They are insulated. Other configurations are the same as those of the first embodiment (see FIGS. 1 to 4).

Therefore, in this embodiment, when a pressure wave of a predetermined cycle is generated in the compression space due to the contact and separation of the two pistons in the compressor (4) with the operation of the refrigerator (R), this compression In the expander (35) communicating with the space through the connecting pipe (7), the displacer reciprocates at the same cycle as the pressure wave in the compression space, and the gas expands in the expansion space to generate cold. The cold head (15) at the tip of the cylinder (36) is cooled to a cryogenic level by repetitive reciprocation of the displacer, and the object to be cooled (2) is kept at the same cryogenic level by the cold heat transfer from the cold head (15). Is maintained at the set temperature.

The compressor (4), the connecting pipe (7), and the high temperature section (38) of the cylinder (36) of the expander (35) are arranged outside the housing (1).
Since the cylinder (36) other than 8), the cold head (15) at the tip thereof, and the object to be cooled (2) are housed in the vacuum chamber (23) in the housing (1), the first embodiment described above is used.
Similarly to the above, the compressor (4) is forcibly cooled by the air from the cooling fan (33) outside the housing (1) to increase the cooling efficiency of the compressor (4) and to increase the compressor (4). Of the refrigerator (R) and the cooling system (S) can be improved.

Further, the high temperature section (38) of the cylinder (36) of the expander (35) is also cooled by the air blown by the cooling fan (33) together with the compressor (4). Cooling can be efficiently performed outside the housing (1), and accordingly, the performance of the cryogenic refrigerator (R) can be further improved and the power consumption of the cooling system (S) can be reduced.

Furthermore, a cylinder (36) other than the high-temperature section (38) of the expander (35) is provided in the vacuum chamber (23) of the housing (1) together with the cold head (15) and the cooled object (2). (1) The bottom wall has an opening (21) fitted and accommodated therein, and this opening (21) is closed by a lid (12) that is a part of the housing (1). The cooling system (S) can be reduced in size and weight by using the (12) and the wall of the housing (1) together.

In each of the above embodiments, the compressor (4) as the refrigerator (R) is connected to the pulse tube (1) via the regenerator (9).
Although a pulse tube refrigerator connected to 4) and a Stirling refrigerator using a free displacer for the expander (35) are used, a GM refrigerator having a Gifford McMahon cycle can also be used.

[0044]

As described above, according to the first aspect of the present invention, there is provided a cryogenic refrigerator comprising a compressor and a cold generating means for cooling a body to be cooled to a set temperature at a cryogenic level. In the system, at least the cryogenic portion of the cold generation means and the object to be cooled are housed inside the housing,
By placing the compressor outside the housing and forcibly cooling this compressor, the compressor is cooled at a lower temperature than when the compressor is housed inside the housing, and the cooling efficiency of the compressor is reduced. And the reliability of the refrigerator and the cooling system can be improved.

According to the second aspect of the present invention, the cryogenic refrigerator is a pulse tube refrigerator having a pulse tube, and an inertance tube and a buffer portion, which are high-temperature portions thereof, are arranged outside the housing. In the invention of claim 3, the cryogenic refrigerator is a Stirling refrigerator having a displacer type expander,
The high temperature part of the expander was arranged outside the housing. Therefore,
According to these inventions, the inertance tube and the buffer portion of the pulse tube refrigerator and the high temperature portion of the expander of the Stirling refrigerator can be efficiently cooled outside the housing, respectively, and the performance of the refrigerator is improved. The power consumption of the cooling system can be reduced.

According to the fourth aspect of the present invention, a vacuum chamber is provided in the housing in which at least the cryogenic portion of the cold generating means and the object to be cooled are inserted through the opening and housed in a vacuum insulated state. Since the opening of the chamber is closed by the lid that is a part of the housing, the cooling system can be reduced in size and weight by using the lid for closing the vacuum chamber and the housing wall. .

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a configuration of a cryogenic cooling system according to a first embodiment of the present invention.

FIG. 2 is a side view of the cryogenic cooling system.

FIG. 3 is a bottom view of the housing.

FIG. 4 is a front view showing a configuration of the refrigerator.

FIG. 5 is a view corresponding to FIG. 4, showing a configuration of a refrigerator according to a second embodiment.

[Explanation of symbols]

 (S) Cryogenic cooling system (R) Cryogenic refrigerator (1) Housing (2) Object to be cooled (4) Compressor (8) Cold generation unit (cold generation means) (9) Cold storage unit (12) Lid (14) Pulse tube (15) Cold head (cryogenic part) (17) Inertance tube (19) Buffer part (21) Opening part (23) Vacuum chamber (33) Cooling fan (cooling means) (35) Expander ( (38) High temperature part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takazo Toshima 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries, Ltd. Sakai Seisakusho Kanaoka Factory F-term (reference) 5C022 AA01 AB39 AB67 AC64

Claims (4)

[Claims] 1. A compressor (4) for compressing a working gas, and a cold generating means (8) for expanding a working gas compressed by the compressor (4) to generate a cryogenic level of cold.
(35) comprising a cryogenic refrigerator (R) comprising:
A cryogenic cooling system for cooling a cooled object (2) to a set temperature at a cryogenic level, wherein at least a cryogenic portion (15) of the cold generating means (8), (35) and a cooled object are provided. (2) is housed inside the housing (1), the compressor (4) is arranged outside the housing (1), and cooling means (forcibly cooling the compressor (4)) 33)
A cryogenic cooling system characterized in that a cryogenic cooling system is provided. 2. The cryogenic cooling system according to claim 1, wherein the cryogenic refrigerator (R) includes a pulse tube (14) having one end connected to a compressor (4) via a regenerator (9). The inertance tube (1) is connected to the other end of the pulse tube (14).
7) A pulse tube refrigerator provided with a cold generation means (8) having a buffer unit (19) connected via the above (7), wherein the inertance tube (17) and the buffer unit (19) are provided in the housing (1). A cryogenic cooling system, which is disposed outside. 3. The cryogenic cooling system according to claim 1, wherein the cryogenic refrigerator (R) is a Stirling refrigerator having a displacer type expander (35) as a cold generating means, and the expander (35). A cryogenic cooling system, characterized in that the high-temperature section (38) is disposed outside the housing (1). 4. The cryogenic cooling system according to claim 1, wherein at least the cold generating means (8), (3) is provided in the housing (1).
A vacuum chamber (23) is provided in which the cryogenic part (15) and the object to be cooled (2) of (5) are fitted through the opening (21) and housed in a vacuum-insulated state. The cryogenic cooling system according to claim 23, wherein the opening (21) of (23) is closed by a lid (12) which is a part of the housing (1).