JP2001289527A - Cryogenic cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: Improve a working efficiency in dismounting an expander from a vacuum vessel of a chiller in a cryogenic refrigerating system generating cryotemperature in a cold head. SOLUTION: A heat conduction block (3a) for mounting an anchor block (3) is installed on the peripheral surface of a cylinder (31). The anchor block (3) attached to the heat conduction block (3a) is supported removably so as to be heat-transferred, on which a lead wire (19) lead from a to-be-cooled body is wound. The anchor block (3) is taken off from the heat conduction block (3a) in dismounting an expander (E) from a vacuum vessel 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 a body to be cooled by generating a cryogenic refrigerator at a cryogenic level, and more particularly to a heat shield structure for a lead wire extending from the body to be cooled. About.

[0002]

2. Description of the Related Art Heretofore, GM (Gifford McMahon) refrigerators, Stirling refrigerators, pulse tube refrigerators, and the like have been known as a kind of small refrigerators that generate cryogenic cooling.

[0003] For example, Japanese Unexamined Patent Publication No. Hei 10-33951
The Stirling refrigerating machine disclosed in Japanese Patent Publication No. 0 is a combination of a vibrating compressor for compressing gas and an expander as a cold generating means for expanding working gas discharged from the compressor. Usually, the expander is arranged in a vacuum vessel together with the object to be cooled for heat insulation.

The above-described expander has a cylindrical cylinder, and a displacer for partitioning the inside of the cylinder into an expansion space and a working space is provided in the cylinder in a reciprocating manner. This displacer is filled with a regenerator, and the regenerator is connected to the expansion space and the working space, respectively. A coil spring that elastically supports the displacer in a reciprocable manner is provided in the working space.
Further, the working space is connected to the compression space of the compressor through the connection pipe, and the gas pressure from the compressor causes the displacer to reciprocate to expand the gas in the expansion space. It is designed to generate cold in the cold head located.

[0005]

When a device or the like utilizing the high-temperature superconductivity effect is used as the object to be cooled by the cold head, a lead extending from the object to be cooled is attached to the wall surface of the vacuum vessel. It is necessary to take out outside the vacuum vessel through the provided lead wire taking out port. At this time, one end of the lead wire on the side to be cooled has a very low temperature (for example, about 80K), while the other end has almost the same temperature as the outside air temperature (for example, about 300K). Causes a large temperature difference. Therefore, in the case of the Stirling refrigerator, as shown in FIG. 6, the intermediate portion of the lead wire (19) extending from the cooled object (2) is connected to the cylinder (31).
The lead wire (19) is cooled while anchoring the lead wire (19), thereby reducing the gradient caused by a large temperature difference between both ends of the lead wire (19). It has been practiced to prevent heat from entering the cooled object (2) from the room temperature side by the wire (19). By cooling the entire lead wire (19) around the cylinder (31) as described above, an effect of reducing the electrical resistance of the lead wire (19) can be obtained.

However, in the above-described apparatus, when the expander (E) of the refrigerator (R) is detached from the vacuum vessel (1), the lead wire (19) wound around the cylinder (31) of the expander (E). Has to be wound off once, and the work of removing the lead wire (19) takes time and effort, resulting in extremely poor work efficiency.

[0007] Many components constituting the refrigerator (R) are very vulnerable to impact.
Parts may be damaged when the lead wire (19) is removed from the cylinder (31), and the refrigerator (R)
It was itself a cause of failure.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a cryogenic cooling system by improving an anchor structure of a lead wire extending from an object to be cooled in a cryogenic cooling system. To easily perform the removal operation from the vacuum vessel.

[0009]

In order to achieve the above object, according to the present invention, the position of the anchor around which the lead extending from the object to be cooled is wound is provided at a position different from that of the cold generating means.

More specifically, according to the first aspect of the present invention, the cryogenic temperature that causes the working gas compressed by the compressor (C) to expand to generate the cryogenic level cold in the cold head (32) of the cold generating means. The refrigerator (R) is connected to the lead wire (19), and the cooled object (2) which is transferred from the cold head (32) and cooled and held at a cryogenic level, and at least one of the cold generating means. A cryogenic cooling system comprising: a vacuum vessel (1) that accommodates a unit, a cooled object (2), and a lead wire (19) in a vacuum insulated state, wherein the cryogenic cooling system is located in the vacuum vessel (1); At least one heat transfer block (3a) for attaching an anchor block, which is fixed to the cold generating means excluding the cold head (32) so as to be able to conduct heat;
An anchor block (3) is provided, which is detachably connected to the heat transfer block (3a) for attaching an anchor block and is capable of winding a lead wire (19) from the object to be cooled (2).

With the above arrangement, when the cold generating means is detached from the vacuum vessel (1), the anchor block (3) around which the lead wire (19) extending from the object to be cooled (2) is wound is anchored. The cold generating means can be removed simply by removing the cold generating means from the mounting heat conducting block (3a), and the lead wire (1) as in the conventional structure in which the lead wire (19) is wound around the cold generating means itself.
9) There is no need to remove itself once, so that the cold generating means can be easily removed from the vacuum vessel (1).

The anchor block (3) around which the lead wire (19) is wound is a heat conduction block (3) for attaching an anchor block fixed to the cold generating means.
(a) is connected and supported so as to be able to conduct heat, so that the cold from the cold generating means is transferred to the anchor block (3) via the heat conducting block (3a) for mounting the anchor block.
And the anchor block (3) is connected to the lead wire (1).
By keeping the temperature gradient at the same level as that of the cold generation means together with 9), it is possible to prevent heat from entering the cooled object (2) by the lead wire (19).

According to the second aspect of the present invention, in the above cryogenic cooling system, the cold generating means has a cylinder (31) in which a displacer (37) is reciprocally fitted.
The anchor block mounting heat conducting block (3a) is fixed to the outer peripheral surface of the cylinder (37).

According to the above configuration, a Stirling refrigerator or a GM refrigerator having a cylinder in which a displacer (37) is fitted can be used as the cryogenic cooling system.

A heat conductive block (3a) for fixing the anchor block is fixed to the outer peripheral surface of the cylinder, and the heat conductive block (3a) for fixing the anchor block is connected to the heat conductive block (3a) so as to be able to conduct heat and to be detachable. By providing the anchor block (3) around which the lead wire (19) from the object to be cooled (2) is wound, the same operation and effect as in claim 1 can be obtained.

According to a third aspect of the present invention, in the cryogenic cooling system, the cold generation means has a pulse tube (P) connected to the compressor (C) via a regenerator (T). A heat conduction block (3a) for attaching an anchor block is fixed to an outer peripheral surface of the regenerator (T). From this,
As the cryogenic cooling system, a pulse tube refrigerator having a regenerator (T) and a pulse tube (P) can be used.

According to the fourth aspect of the present invention, the anchor block (3) is formed of a highly heat-conductive cylinder. Also,
According to the invention of claim 5, the anchor block (3) is formed of a solid body.

According to these inventions, the cold from the cold generating means is supplied to the heat conduction block (3) for attaching the anchor block.
Through (a), heat is more easily transferred to the entire anchor block (3), and the entire anchor block (3) can be cooled more efficiently.

[0019]

(Embodiment 1) FIG. 1 shows a cryogenic cooling system according to Embodiment 1 of the present invention.
For example, the cooled objects (2) and (R) containing the high-temperature superconducting material, which are normally operated while being cooled and maintained at the set temperature of the cryogenic level, are Stirling for cooling the cooled object (2). This is a cryogenic refrigerator comprising a refrigerator, and this refrigerator (R) is configured by combining a double piston type compressor (C) and a free displacer type expander (E).

That is, the compressor (C) has, for example, a closed cylindrical casing (5) extending vertically.
In the casing (5), one cylindrical cylinder (6) having both ends opened and extending in the vertical direction is accommodated so as to be arranged concentrically with the casing (5). A disk-shaped flange (7) extending in a direction perpendicular to the center line of the cylinder (6) is provided on the outer periphery at the center in the length direction of the cylinder (6).
Are formed integrally, and at the outer peripheral end of the flange (7),
A cylindrical fitting portion (8) extending in the vertical direction concentrically with the cylinder (6) is integrally formed. A cylindrical yoke member (9) is fitted and fixed to the outer periphery of the cylinder (6), and the cylinder (6), the flange (7), the fitting portion (8), and the yoke member (9) are fitted. ) Is made of a magnetic material such as pure iron and constitutes a yoke (yoke). The fitting portion (8) is immovably fitted and fixed to the inner periphery of the casing (5), whereby the cylinder (6) is integrally fixed to the casing (5).

In the cylinder (6), a bottomed cylindrical cylinder 1 is provided.
A pair of pistons (10), (10) are slidably fitted with their bottoms facing each other, and a portion surrounded by a cylinder (6) between the pistons (10), (10). Is a compression space (11), and this compression space (1)
1) is filled with a working gas. That is, the space in the closed casing (5) includes the cylinder (6), the flange (7), the fitting portion (8), and the pistons (10), (10).
The compression space (11) and the other back pressure space (1
2) and (12). The cylinder (6), the flange (7) and the fitting portion (8) are formed with a gas passage (13) penetrating in a radial direction from the inner peripheral surface of the cylinder (6) to the outer peripheral surface of the fitting portion (8). I have. The inner end of the gas passage (13) is always in communication with the compression space (11), while the outer end has a through hole (14) opened in the casing (5) and a connection connected to the through hole (14). Tube (2
8) to the expander (E).

The pistons (10), (10) are drivingly connected to linear motors (15), (15) as drive sources for reciprocatingly driving the respective pistons (10).
Each of the linear motors (15) is provided with a corresponding one of the yoke members (9).
A driving magnet (16) composed of an annular permanent magnet fitted and fixed in a state where an annular space is provided with an inner peripheral surface of the fitting portion (8) on the outer periphery of the driving magnet (16). The yoke uses the yoke member (9), the flange (7), and the fitting portion (8) as a yoke and has a predetermined strength in a magnetic gap formed by a space between the outer peripheral surface of the driving magnet (16) and the inner peripheral surface of the fitting portion (8). (Static magnetic field).

Each of the pistons (10) has a flange portion (10a) extending radially outward from the back side, that is, the opening end opposite to the center of the cylinder (6). A bottomed cylindrical bobbin (17) as a drive unit of the linear motor (15) is integrally connected to move on the bottom wall side. The opening side of the bobbin (17) extends concentrically with the piston (10) toward the center of the cylinder (6), and has a tip portion which is connected to the outer peripheral surface of the driving magnet (16) and the inner peripheral surface of the fitting portion (8). Are arranged so as to be able to reciprocate up and down in a magnetic gap therebetween. A drive coil (18) (solenoid) composed of an electromagnetic coil is wound around the outer periphery of the bobbin (17) near the tip thereof at a position corresponding to the drive magnet (16). Then, the bobbin (17) and the piston (1)
0) (specifically, the entire movable portion such as the drive coil (18)) constitutes a movable portion (20).
0) is relatively movable with respect to the casing (5), the cylinder (6) and the like. Each drive coil (18) is connected to an AC power source (not shown) via current introduction terminals (22) and (22), which are supported in a state insulated by the lead wire (21) and the casing (5), respectively. And the drive coil (1) of the linear motors (15) and (15)
8) By supplying AC in synchronization with (18),
The pistons (10) and (10) are reciprocated synchronously in opposite directions so as to come and go at a predetermined operating frequency so as to generate a gas pressure of a predetermined cycle in the compression space (11). I have.

On the inner wall surface of each end of the casing (5), a cylindrical casing-side spring mounting member (24) is protruded at a position on the axis of the cylinder (6). On the other hand, a piston-side spring mounting member (25) is integrally fixed to the open end of each piston (10), and a piston spring (26) made of a coil spring is fixed to the casing-side spring mounting member (24). One end is immovably attached, and the other end of the piston spring (26) is immovably attached to the piston side spring attachment member (25). That is, a piston spring (26) is hung between the inner wall surface of the casing (5) and the back side of each piston (10), and the piston (10) is moved by the piston spring (26). ,
Therefore, it is elastically supported so as to be able to reciprocate in the horizontal direction with respect to the cylinder (6) fixed integrally with the casing (5).

On the other hand, the expander (E) has a cylinder (31) extending in the horizontal direction, and an opening at the front end (left end) of the cylinder (31) is a cold head (32) which is a cryogenic part. The opening on the base end side (the right end side) is closed by a flange (33), and the object to be cooled (2) is arranged to be able to conduct heat to the cold head (32). In the cylinder (31), the internal space is defined as an expansion space (35) on the distal side and an operating space (36) on the proximal side.
Hollow cylindrical free displacer (3
7) is fitted so as to be able to reciprocate in the horizontal direction. This displacer (37) has a regenerator (38)
(Regeneration heat exchanger), the regenerator (38)
Are communication holes (3) opened at both ends of the displacer (37).
9) and (40) communicate with the expansion space (35) and the working space (36), respectively.

At the base end of the displacer (37), a displacer-side spring mounting portion (42) is provided. In the flange (33), the working space (3
A flange-side spring mounting portion (43) is provided in a portion facing 6). A left end (one end) of a displacer spring (44) composed of a coil spring located in the working space (36) is immovably attached to the displacer-side spring attachment portion (42). ) Is immovably attached to the flange-side spring attachment portion (43). Therefore, the flange (33) and the displacer (3)
7) and a displacer spring (44) is stretched over the displacer spring (44).
As a result, the displacer (37) is elastically supported so as to be able to reciprocate in the horizontal direction with respect to the flange (33), and thus to the cylinder (31) fixed integrally with the flange (33).

Further, a gas hole (45) communicating with the working space (36) is formed through the flange (33).
The connecting pipe (28) is fitted and fixed to the outer end side of the gas hole (45) in an airtight manner. Therefore, the working space (36) of the expander (E) is connected to the compression space (11) of the compressor (C) through the connecting pipe (28), and the expander is operated by the gas pressure from the compressor (C). The displacer (37) of (E) is reciprocated in the cylinder (31) to expand the working gas in the expansion space (35), so that the cold head (32) at the tip of the cylinder (31) is cooled at an extremely low temperature. Is generated, and the object to be cooled (2) is cooled and maintained at a similar cryogenic level by the cold.

In the expander (E), the cylinder (31) other than the portion around the working space (36) is disposed in the vacuum vessel (1) together with the object to be cooled (2). The cylinder (31) and the object to be cooled (2) are thermally insulated by the vacuum in (1). The vacuum vessel (1) is formed with an opening (46) through which the cylinder (31) and its cold head (32) can be inserted, and the opening (46) is formed integrally with the cylinder (31). It is closed in an airtight manner by the lid (47).

The working gas is supplied to the compression space (11) of the compressor (C), the cylinder (31) of the expander (E) (the working space (36), the expansion space (35), the regenerator ( 3
8) and the inside of the connecting pipe (28),
In addition, in order to properly maintain the movement of the movable part (20) of the compressor (C), each back pressure space (1
2) is also filled and sealed. Further, cooling fins (41), (41),... For cooling the working gas in the working space (36) project into the cylinder (31) around the working space (36) of the expander (E). Has been established.

Further, a lead wire (19) extends from the cooled object (2) disposed on the cold head (32). The intermediate portion of the lead wire (19) is uniformly wound around the anchor block (3), and the anchor block (3) is arranged opposite to the cylinder (31) at a predetermined interval, and is arranged at a predetermined distance from the cylinder (31). A plurality of anchor block mounting heat conductive blocks (3a), (3a),... Fixed to the outer peripheral surface so as to be able to conduct heat are connected and fixed so as to be able to conduct heat and to be detachable. And the lead wire (19)
After being wound around the anchor block (3) as described above, it extends to the outside of the vacuum vessel (1) through a lead wire take-out port (4) that penetrates the wall of the vacuum vessel (1) in an airtight manner. Have been. The lead wire (19) is used to input and output electric signals and the like to and from the cooled object (2).

FIG. 2A shows that the anchor block (3) around which the lead wire (19) is wound is a heat conduction block (3).
FIG. 2 (b) shows the state of being connected and supported in FIG.
Shows cross-sectional views of FIG. FIG. 3 (a)
Means that the anchor block (3) is a heat conducting block (3a)
FIG. 3 (b) shows a state in which
The cross-sectional views of FIG. In this embodiment, three heat conduction blocks (3a) for connecting and supporting the anchor block (3) are provided at substantially equal intervals on the outer peripheral surface of the cylinder (31). A pair of mounting portions project from the outer peripheral surface of the anchor block (3) so as to face each other in the diametrical direction. The distal ends of the mounting screws (3b) penetrating both mounting portions are connected to the heat conduction block (3a). ) Is screwed into the anchor block (3) so that the mounting screws (3) are attached.
By b), it is detachably fastened and fixed to the heat conduction block (3a).

The structure of the anchor block (3) is made of a thin cylinder made of a good heat conductor as shown in FIG. 5 (a) and a material having poor heat conductivity as shown in FIG. 5 (b). As shown in FIG. 5 (c), a thick cylinder and a solid body made of a material having poor heat conductivity can be used. Examples of the good heat conductor include copper and aluminum, and examples of the material having poor heat conductivity include SUS and resin.

Next, in this embodiment, the refrigerator (R)
The process of removing the cover will be described. First, after the inside of the vacuum vessel (1) is opened to the atmosphere, the mounting screw (3b) is removed, so that the anchor block (3) around which the lead wire (19) from the object to be cooled (2) is wound is heated. Conduction block (3
Remove from a). Next, the contact between the cold head (32) and the object to be cooled (2) and the connection between the vacuum vessel (1) and the lid (47) on the side of the expander (E) are removed, and the cylinder of the expander (E) is removed. By extracting (31) from the opening (46) of the vacuum vessel (1), the refrigerator (R) can be removed from the vacuum vessel (1) as shown in FIG.

Accordingly, in the present embodiment, the expander (E) is removed from the vacuum vessel (1) while the lead wire (19) is wound around the anchor block (3) as described above.
The work of removing the lead wire (19) from the cylinder (31) as in the conventional cryogenic refrigerator (R) shown in FIG. 6 can be omitted, and the work efficiency can be greatly improved. Further, since the detaching operation becomes very easy, it is possible to surely reduce the problem that the refrigerator is broken down due to an operation mistake during the detachment as in the related art.

With the above configuration, when the expander (E) is removed from the vacuum vessel (1), the anchor block (3) around which the lead wire (19) is wound.
Need only be removed from the heat transfer block (3a) for fixing the anchor block to the outer peripheral surface of the cylinder (31), and the lead wire (19) is wound like the structure in which the lead wire (19) is wound around the cylinder (31). There is no need to remove the expander itself, so that the expander (E) can be easily removed from the vacuum vessel (1).

The anchor block (3) around which the lead wire (19) is wound is connected to the anchor block mounting heat conducting block (3a) on the outer peripheral surface of the cylinder (31) of the expander (E). Cylinder (3
The cold heat from 1) is transmitted to the anchor block (3) via the heat conductive block (3a) for attaching the anchor block, which has heat conductivity, and the anchor block (3) is transferred to the cylinder (31) together with the lead wire (19). By keeping the temperature gradient at the same level as that described above, it is possible to prevent heat from entering the cooled object (2) by the lead wire (19).

Since the lead wire (19) extending from the object to be cooled (2) is wound around the anchor block (3) with a sufficient length, the operation side of the object to be cooled (about 300K) and the object to be cooled. (2) It is possible to reliably prevent heat from entering the object to be cooled (2) from the object-to-be-cooled member operating device side caused by a large temperature difference from (about 80K). (Embodiment 2) Fig. 7 shows a cryogenic cooling system according to Embodiment 2 of the present invention.
The same parts as those in FIG. 6 are denoted by the same reference numerals, and detailed description thereof will be omitted.) In this embodiment, the cryogenic refrigerator (R)
Consists of a U-shaped pulse tube refrigerator. That is, this refrigerator (R) connects the compressor (C) to one end of the pulse tube (P) via the regenerator (T), and connects the other end of the pulse tube (P) to the buffer (B). It is configured by connecting via an inertance tube (48).

In the compressor (C), the pressure and volume of the working gas change due to the reciprocating motion of the piston (10) as in the first embodiment. The compressor (C) communicates with a high-temperature end (49) of a regenerator (T) (a regenerative heat exchanger) via a connection pipe (28). The regenerator (T) contains a regenerator material made of lead, copper, or the like inside a cylindrical body. High temperature end (49) of compressor (C) side of regenerator (T)
Takes the compression heat of the working gas during the compression process of the compressor (C), and this heat is radiated to the outside. Further, a low-temperature end (50) of the regenerator (T) opposite to the compressor (C) is connected to the pulse tube (P).

The regenerator (T) and the pulse tube (P) are arranged substantially parallel to each other, and are connected by a communication portion (51) extending in a direction substantially orthogonal to both.
1) is covered by a cold head (32) that generates cryogenic levels of cold. The pulse tube (P), the regenerator (T), and the object to be cooled (2) are housed in the vacuum vessel (1) to prevent heat from entering from outside. on the other hand,
Compressor (C), buffer (B) and hot end (49),
Since (51) involves heat generation, it is installed outside the vacuum vessel (1).

(B) is a buffer having a space inside,
The space in the buffer (B) is an inertance tube (48)
The working gas pushed out of the pulse tube (P) is further cooled by adiabatic expansion in the inertance tube (48), and is connected to the high-temperature end (52) of the pulse tube (P) via B), and the flow of the working gas is controlled in a closed space in the buffer (B). That is, the working gas supplied from the compressor (C) is supplied to the connection pipe (28), the regenerator (T), and the communication section (5).
1), introduced into the buffer (B) through the pulse tube (P) and the inertance tube (48).

In this embodiment, the lead wire (19) drawn from the cooled object (2) disposed on the cold head (32) is uniformly wound around the anchor block (3), (3) a plurality of heat transfer blocks (3a) for mounting an anchor block, which are opposed to the regenerator (T) at a predetermined interval and are fixed to the outer peripheral surface of the regenerator (T) so as to be able to conduct heat. (3a), are connected and fixed so as to be able to conduct heat and to be removable. Then, after the lead wire (19) is wound around the anchor block (3) as described above, the vacuum container (1) is passed through the wall of the vacuum container (1) in an airtight manner through a lead wire outlet port (4). It is extended outside (1). Other configurations are the same as those in the first embodiment.

Next, the operation of the U-shaped pulse tube refrigerator of this embodiment will be described. When the piston (10) performs a compression operation in the compression process of the compressor (C), the compressed working gas passes through the connection pipe (28) and passes through the high-temperature end (4) of the regenerator (T).
9) and after radiating the heat of compression in the regenerator (T), flows into the pulse tube (P) through the communication part (51), and compresses the working gas in the pulse tube (P). The heat of compression is released through the wall of the pulse tube (P). Further, the working gas flows into the buffer (B) through the inertance pipe (48). Thereafter, when the piston (10) performs a suction operation during the expansion process of the compressor (C), the working gas is transferred to the buffer (B).
From the buffer (B) through the inertance tube (48), adiabatically expands in the pulse tube (P) to further lower the temperature.
The cold working gas is supplied to the cold head (32)
After cooling, it flows in a direction returning to the compressor (C) through the regenerator (T) and the connection pipe (51). When the compression / expansion cycle of the working gas as described above is repeated, the heat is removed at the high temperature ends (49) and (52) before the expansion process of the compressor (C). Receives heat from the wall of the pulse tube (P), the cold end (53) of the pulse tube (P) becomes the coldest part, and it is possible to obtain a cryogenic level of cold in the cold head (32).

Next, the process of removing the refrigerator (R) in the present embodiment will be described. First, after the inside of the vacuum vessel (1) is opened to the atmosphere, the mounting screw (3b) is removed, so that the anchor block (3) around which the lead wire (19) from the object to be cooled (2) is wound is heated. Conduction block (3
Remove from a). Next, contact between the cold head (32) and the object to be cooled (2) and connection between the vacuum vessel (1) and the lid (47) on the side of the pulse tube (P) are removed, and the regenerator (T) and the pulse are removed. The refrigerator (R) can be removed from the vacuum vessel (1) by extracting the pipe (P) from the opening (46) of the vacuum vessel (1).

Therefore, also in this embodiment, the lead wire (1
In 9), since the pulse tube (P) and the regenerator (T) can be removed from the vacuum vessel (1) while being wound around the anchor block (3), the same operation and effect as those in the first embodiment can be obtained. .

In this embodiment, the heat conduction block (3
a) is provided on the outer surface of the regenerator (T), and the anchor clock (3) is detachably fixed to the heat conduction block (3a), so that the lead wire extending from the object to be cooled (2) is anchored. However, the present invention is not limited to this. For example,
By providing the heat conduction block (3a) on the outer surface of the pulse tube (P) and fixing the anchor block (3) on the pulse tube (P) side, it is also possible to take the anchor of the lead wire extending from the object to be cooled. It is. (Embodiment 3) FIG. 8 shows the overall configuration of a cryogenic cooling system according to Embodiment 3 of the present invention, and the cryogenic refrigerator (R) comprises a GM refrigerator having a Gifford McMahon cycle. That is, the refrigerator (R) is provided with the cylinder (3)
It comprises an expander (E) for expanding a high-pressure working gas by reciprocating a displacer (37) in 1), and a compressor unit (Y) for compressing the working gas.

The compressor (Y) is provided in each of the first and second embodiments.
Unlike the second compressor, the low-pressure working gas sucked from the suction port (61) is compressed and discharged from the discharge port (60). On the other hand, the expander (E) includes a closed motor head (54). The motor head (5
4) high pressure gas inlet (55) and low pressure gas outlet (56)
The high-pressure gas inlet (55) is connected to a discharge port (60) of the compressor unit (Y) via a high-pressure pipe (57), and the low-pressure gas outlet (56) is suctioned by the compressor (Y). Ports (61) are connected to each other through low-pressure pipes (58).

In the cylinder (31), an expansion space (35) and a working chamber (59) are defined by a displacer (37). Then, the motor head (5)
A drive mechanism (not shown) for driving the motor (62) to reciprocate the displacer (37) in the cylinder (31) and a cylinder (31) in synchronism with the reciprocation of the displacer (37). ) Expansion space (3)
5) Switching to a high-pressure valve opening state for supplying high-pressure working gas from the high-pressure gas inlet (55) and a low-pressure valve opening state for discharging the working gas in the expansion space (35) to the low-pressure gas outlet (56). An alternate switching valve (not shown) is provided.

By switching the switching valve in the motor head (54), the high-pressure pipe (57) and the low-pressure pipe (58) are alternately connected to the cylinder (31) of the expander (E). The reciprocating motion causes the working gas to expand in the expansion space (35) in the cylinder (31) to cause cryogenic cooling at the cold head (32).

In the present embodiment, as in the first embodiment, the intermediate portion of the lead wire (19) extending from the cooled object (2) disposed on the cold head (32) at the left end of the cylinder (31) is a cylinder (31). 31) is uniformly wound around an anchor block (3) fixed via a heat conduction block (3a), and this lead wire (19) is connected to a lead wire outlet port (4) in the wall of the vacuum vessel (1). And extends outside the vacuum vessel (1).

In the process of removing the refrigerator (R), the interior of the vacuum vessel (1) is opened to the atmosphere, and then the mounting screws (3b) are removed to remove the lead wires (2) from the cooled object (2). Anchor block (3) around which 19) is wound
Is removed from the heat conduction block (3a). Next, the contact between the cold head (32) and the object to be cooled (2) and the connection between the vacuum vessel (1) and the lid (47) on the cylinder (31) side are removed, and the expander (E) is placed in the vacuum vessel. By extracting the refrigerator (R) from the opening (46) of (1), the refrigerator (R) can be removed from the vacuum vessel (1).

Therefore, also in this embodiment, the lead wire (1
In (9), since the refrigerator (R) can be removed from the vacuum vessel (1) while being wound around the anchor block (3), the same operation and effect as in the first embodiment can be obtained.

[0052]

As described above, according to the first aspect of the present invention, at least a cryogenic refrigerator for generating a cryogenic level of cold in a cold head, an object to be cooled cooled and held at a cryogenic level, A cryogenic cooling system comprising a vacuum vessel containing the cold generating means and the like, wherein at least one anchor block mounting heat conductive block fixed to the cold generating means excluding the cold head so as to be able to conduct heat, By providing an anchor block which is connected to the heat conduction block for anchor block attachment so as to be able to conduct heat and is detachable and winds a lead wire from the object to be cooled, the cold generating means is removed from the vacuum vessel. When removing the anchor block, just remove the anchor block around which the lead wire is wound from the heat conduction block for attaching the anchor block. The anchor block facilitates removal of the generating means from the inside of the vacuum vessel, and heat of the anchor block is transferred to the anchor block via the heat conductive block for mounting the anchor block, which has heat conductivity. The block and the lead are kept at the same temperature gradient as that of the cold generating means to prevent the lead from invading heat to the object to be cooled.

According to the second aspect of the present invention, the cold generating means has a cylinder in which a displacer is reciprocally fitted, and a heat conductive block for attaching an anchor block is fixed to an outer peripheral surface of the cylinder. I have. Further, in the invention according to claim 3, the cold generation means has a pulse tube connected to the compressor via a regenerator, and a heat conduction block for attaching an anchor block is fixed to an outer peripheral surface of the regenerator. I have.

With the above configuration, a Stirling refrigerator and a GM refrigerator having a cylinder in which a displacer is fitted, or a pulse tube refrigerator having a regenerator can be used as the cryogenic cooling system. By providing the anchor block on the outer peripheral surface of the regenerator via the heat conduction block for attaching the anchor block, the same operation and effect as in claim 1 can be obtained.

According to the fourth aspect of the present invention, the anchor block is made of a highly heat-conductive cylinder. Claim 5
According to the invention, the anchor block is formed of a solid body.

According to these inventions, the cold from the cold generating means is more easily transferred to the anchor block, and the entire anchor block can be efficiently cooled.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a Stirling refrigerator according to a first embodiment of the present invention.

FIG. 2 is an enlarged view showing a state in which the anchor block according to the embodiment of the present invention is connected and supported by a heat conductive block.

FIG. 3 is an enlarged view showing a state in which the anchor block according to the embodiment of the present invention has been removed from the heat conductive block.

FIG. 4 is a cross-sectional view schematically showing the cryogenic refrigerator after removing the anchor block according to the embodiment of the present invention.

FIG. 5 is another configuration diagram of the anchor block according to the embodiment of the present invention.

FIG. 6 is a sectional view showing a conventional cryogenic refrigerator.

FIG. 7 is a sectional view schematically showing a U-shaped pulse tube refrigerator according to a second embodiment of the present invention.

FIG. 8 is a sectional view schematically showing a GM refrigerator according to Embodiment 3 of the present invention.

[Explanation of symbols]

 (1) Vacuum container (2) Object to be cooled (3) Anchor block (3a) Heat conduction block (3b) Mounting screw (4) Lead wire extraction port (19) Lead wire (31) Cylinder (32) Cold head ( 35) Expansion space (48) Inertance pipe (51) Communication part (54) Motor head (B) Buffer (C) Compressor (E) Expander (R) Refrigerator (Y) Compressor unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryuzo Toshima 1304 Kanaokacho, Sakai City, Osaka Daikin Industries, Ltd. Sakai Seisakusho Kanaoka Factory F-term (reference) 4M114 AA31 CC05 CC11 DA02 DA33 DA34 DA51 DA52

Claims (5)

[Claims] 1. A cryogenic refrigerator (R) for expanding a working gas compressed by a compressor (C) to generate a cryogenic level of cold in a cold head (32) of a cold generating means; 19) is connected to the cold head (3).
The object to be cooled (2), which is transferred from the element (2) and is cooled and held at a cryogenic level, and at least a part of the cold generating means, the object to be cooled (2) and the lead wire (19) are housed in a vacuum insulated state. A cryogenic cooling system, comprising: a vacuum vessel (1) that performs heat transfer, wherein at least one of the vacuum vessels (1) is located in the vacuum vessel (1) and is fixed to a cold generating means other than the cold head (32) so as to be able to conduct heat. A heat transfer block (3a) for attaching an anchor block; and a lead wire (19) that is removably connected to the heat transfer block (3a) for attaching an anchor block and that is detachably connected to the object (2). A cryogenic cooling system, comprising: 2. The cryogenic cooling system according to claim 1, wherein the cold generating means has a cylinder (31) in which a displacer (37) is reciprocally fitted, and an outer periphery of the cylinder (37). A cryogenic cooling system, wherein a heat conduction block (3a) for attaching an anchor block is fixed to a surface. 3. The cryogenic cooling system according to claim 1, wherein the cold generation means has a pulse tube (P) connected to the compressor (C) via a regenerator (T). A cryogenic cooling system, wherein a heat conductive block (3a) for attaching an anchor block is fixed to an outer peripheral surface of T). 4. The cryogenic cooling system according to claim 1, wherein the anchor block (3) is formed of a cylinder having high thermal conductivity. 5. The cryogenic cooling system according to claim 1, wherein the anchor block (3) is formed of a solid body.