JP2001304710A - Cold storage type refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold storage type refrigerating machine in which a refrigerant gas is surely sealed by maintaining a sealing part exposed to cryogenic conditions and influenced by a strong magnetic field in a stable state. SOLUTION: The cold storage type refrigerating machine has the sealing parts 25, 25a, 25b constituted by arranging a first magnet 27, a first seal ring 28 and a second seal ring 29 from the inner diameter side to the outer diameter side of a groove 26 of displacers 15, 15a, 15b, and further provided with a second magnet 30 in a cylinder 12 and a guide 32 on the side of the displacer extending toward the bottom.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative refrigerator, and more particularly to a regenerative refrigerator having an improved seal provided on a displacer (regenerator) that slides in a cylinder.

[0002]

2. Description of the Related Art Recent regenerative refrigerators have made remarkable progress in technological development and have realized those capable of maintaining an extremely low temperature of 4 K. Instead of conventional immersion cooling with liquid helium, they have been realized. It has been spotlighted as a small cooling device for cooling superconducting magnet devices.

In this type of refrigerator, a first displacer having, for example, a net-like regenerator material and a second displacer having, for example, a spherical regenerator material are accommodated in a cylinder, and the driving force of a crankshaft is applied thereto via a motor. The first displacer and the second displacer in the cylinder are slid forward and backward to expand the refrigerant gas in the cylinder and then return to the compressor.

In this type of refrigerator, a seal portion is provided in each of the first displacer and the second displacer, and when the first displacer and the second displacer are slid forward and backward in the cylinder, refrigerant gas is transmitted through the seal portion. It is sealed to reduce wasteful energy consumption.

[0005] As an example, a seal portion used in the first displacer and the second displacer has a structure shown in FIG.

The seal portion 1 slides forward and backward in the cylinder 2, and a spring ring 6, a first seal ring 7, and a two-stage stack accommodated in a groove 5 provided in a circumferential direction of a displacer 4 filled with a cold storage material 3 Of the second seal ring 8,
The elastic force of the spring ring 6 is applied via the first seal ring 7
A pressing force is applied to the stacked second seal ring 8, and the pressing force causes the double stacked second seal ring 8 to slide against the wall surface of the cylinder 2.

As described above, in the conventional regenerative refrigerator, the seal portion 1 is provided on the displacer 4 and the displacer 4 is provided.
When the gas is slid in the cylinder 2, the refrigerant gas in the vessel is sealed by the sealing portion 1, and the cold storage material 3 is made to perform effective cold heat storage when the refrigerant gas expands.

[0008]

In the conventional regenerative refrigerator shown in FIG. 11, even when the sealing effect of the refrigerant gas is maintained as designed at the beginning of assembly, the refrigerator is kept at a very low temperature for many years. Some problems have arisen, such as being maintained and affected by the strong magnetic field generated during operation.

A conventional regenerative refrigerator is a displacer 4
The center axis CL of the displacer 4 and the center axis CL of the cylinder 2 are made to coincide with each other at the beginning of storage in the cylinder 2, and the gap L between the side end surface of the displacer 4 and the wall surface of the cylinder 2 is maintained at the designed dimension. Even if you have
When the temperature in the vessel is maintained at 4K, the displacer 4 contracts, and with this contraction, the first seal system ring 7 and the two-stage second seal system ring 8 have been moved from the spring rig 6 until now. The pressing force applied to the wall surface of the cylinder 2 through the cylinder becomes uneven locally in the circumferential direction, and furthermore, the material of the seal portion 1 undergoes plastic deformation under the influence of the strong magnetic field generated during operation. Was caused. For this reason, during operation, the regenerative refrigerator operates as shown in FIG. 12, for example, when an unexpected external force F is applied to the displacer 4.
The bottom end of the cylinder 1 is biased or one-sided against the wall surface of the cylinder 2 or, as shown in FIG.
May a gap L ₁ occurs and the wall surface of the cylinder 2,
During the compression operation, the refrigerant gas absorbs the cold energy from the cold storage material 3, and during the expansion operation, the cold gas heat storage of the refrigerant gas into the cold storage material 3 is hindered, so that there is a disadvantage that the effective cold heat storage cannot be performed.

[0010] The present invention has been made in view of such circumstances, and maintains a seal portion exposed to an extremely low temperature and affected by a strong magnetic field in a stable state, thereby reliably sealing a refrigerant gas. It is an object of the present invention to provide a regenerative refrigerator.

[0011]

According to a first aspect of the present invention, a regenerative refrigerator according to the present invention is housed in a cylinder and slides on a wall surface of the cylinder in order to achieve the above object. In the regenerative refrigerator provided with a seal portion in the displacer, the seal portion is mounted in a groove formed in the displacer, and the first magnet and the first seal are arranged in order from the inner diameter side to the outer diameter side of the groove. The ring and the second seal ring are arranged and arranged, and the second magnet is embedded in a cylinder facing the second seal ring, while a guide is provided in a groove formed on the side facing the bottom of the displacer.

[0012] Further, a regenerative refrigerator according to the present invention, as described in claim 2, achieves the above object.
In a regenerative refrigerator provided with a seal portion on a displacer accommodated in a cylinder and sliding back and forth on a wall surface of the cylinder, the seal portion includes a first magnet mounted in a groove formed in the displacer, and a first magnet mounted on the displacer. And a guide provided in a groove formed on the side facing the bottom of the displacer.

In order to achieve the above object, a regenerative refrigerator according to the present invention has the following features.
In a regenerative refrigerator provided with a seal portion on a displacer that is housed in a cylinder and slides back and forth on the wall surface of the cylinder, the seal portion is mounted in a groove formed in the displacer and has an outer diameter from an inner diameter side of the groove. A pair of magnets having the same polarity and a second seal ring are arranged and arranged in order toward the side, while a guide is provided in a groove formed on the side facing the bottom of the displacer.

According to a fourth aspect of the present invention, there is provided a regenerative refrigerator according to the present invention.
In a regenerative refrigerator provided with a seal portion on a displacer that is housed in a cylinder and slides back and forth on the wall surface of the cylinder, the seal portion is mounted in a groove formed in the displacer and has an outer diameter from an inner diameter side of the groove. A regenerator, a first seal ring, and a second seal ring are arranged in order toward the side, and a guide is provided in a groove formed on the side facing the bottom of the displacer.

According to a fifth aspect of the present invention, there is provided a regenerative refrigerator according to the present invention.
In a regenerative refrigerator provided with a seal in a displacer housed in a cylinder and sliding back and forth on the wall of the cylinder, the seal is mounted in a groove formed in the cylinder and has an inner diameter from an outer diameter side of the groove. Towards the side,
The regenerator, the first seal ring, and the second seal ring are arranged and arranged, and a guide is provided in a groove formed on the side facing the bottom of the displacer.

According to a sixth aspect of the present invention, there is provided a regenerative refrigerator according to the present invention.
The regenerator is a liquid filled in one of a bag, a capsule, and a tube.

[0017] In order to achieve the above object, a regenerative refrigerator according to the present invention has the following features.
The first seal ring and the second seal ring are both made of Teflon.

In order to achieve the above object, a regenerative refrigerator according to the present invention has the following features.
In a regenerative refrigerator provided with a seal portion on a displacer that is housed in a cylinder and slides back and forth on the wall surface of the cylinder, the seal portion is constituted by a spring ring surrounded by a jacket and provided on the cylinder, The guide is provided in a groove formed on the side facing the bottom of the displacer.

In order to achieve the above object, a regenerative refrigerator according to the present invention has the following features.
In a regenerative refrigerator provided with a seal portion on a displacer that is housed in a cylinder and slides back and forth on the wall surface of the cylinder, the seal portion is surrounded by an outer coating and extends from the cylinder inner diameter side to the outer diameter side. In this order, a ring piece and a spring ring are provided on the cylinder, and a guide is provided in a groove formed on the side facing the bottom of the displacer.

According to a tenth aspect of the present invention, there is provided a regenerative refrigerator according to the present invention, wherein the regenerative refrigerator is sealed in a displacer which is housed in a cylinder and slides on a wall surface of the cylinder. In the regenerative refrigerator including the portion, the seal portion is formed of a flexible sheet that closes a gap between the cylinder and the displacer.

In order to achieve the above object, in the regenerative refrigerator according to the present invention, the connecting position between the cylinder and the displacer is set at the same height. It was installed in.

In the regenerative refrigerator according to the present invention, in order to achieve the above-mentioned object, the connecting position between the cylinder and the displacer is set at different heights. It was installed.

[0023]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a regenerative refrigerator according to the present invention.

FIG. 1 shows a first embodiment of a regenerative refrigerator according to the present invention.
It is an outline longitudinal section showing an embodiment.

The regenerative refrigerator according to the present embodiment will be described by taking a Gifford McMahon type refrigerator as an example.

This Gifford McMahon type refrigerator has:
The system includes a refrigeration generator 10 and a refrigerant gas supply / discharge unit 11 for supplying / discharging the refrigerant gas to / from the refrigeration generator 10.

The refrigeration generator 10 includes a displacer 15 housed in a cylinder 12 and sliding forward and backward with a driving force applied from a motor 14 via a crankshaft 13.

The displacer 15 is divided into a first displacer 15a and a second displacer 15b which are connected by a connecting portion 16, and each displacer 15a, 15b
The inside is filled with net-like or spherical cold storage materials 17a and 17b.

On the other hand, the refrigerant gas supply / discharge unit 11 includes a valve 18a,
18b, a refrigerant gas supply pipe 20 for supplying a refrigerant gas to the refrigeration generator 10 with a compressor 19 interposed,
And a refrigerant gas return pipe 21 for returning the refrigerant gas from the compressor to the compressor 19. During the refrigerant gas compression operation, the refrigerant gas from the compressor is supplied to the first displacer 15 a and the second
The cold storage material 17a,
While the refrigerant gas is cooled by the regenerative cold energy from the refrigerant gas 17b, during the expansion operation of the refrigerant gas, the cold energy generated with the expansion of the refrigerant gas is supplied to the regenerator materials 17a and 17b, and then the refrigerant is supplied to the compressor 19 through the outlet 23. I am going to put it back.

As described above, the Gifford McMahon type refrigerator keeps the refrigerant gas at an extremely low temperature by repeatedly compressing and expanding the refrigerant gas, and uses the cold heat to, for example, the superconducting magnet device or the heat accommodating the superconducting magnet device. Give to the shield plate.

In the Gifford McMahon type refrigerator, when the refrigerant gas is repeatedly compressed and expanded, seal portions 25a and 25b are provided on sliding surfaces 24a and 24b of the respective displacers 15a and 15b with respect to the cylinder 12. When the displacers 15a, 15b slide forward and backward, the path (leakage) of the refrigerant gas to the sliding surfaces 24a, 24b is prevented.

As shown in FIG. 2, when one of the seal portions 25a and 25b is taken out as a representative example, the seal portion 25 has a groove 26 provided in the circumferential direction of the displacer 15 filled with the cold storage material 17. And a first magnet 27 such as a permanent magnet or an induction electromagnet, a first seal ring 28 made of Teflon, and a second seal ring made of two-stage Teflon which are arranged from the inner diameter side to the outer diameter side. 29
And a second magnet 30, such as a permanent magnet or an induction electromagnet, housed inside the wall on the cylinder 12 side.

Each of the magnets 27 and 30 has a shape of a divided fan, a ring having a V-shaped notch formed locally along the circumferential direction, or a wire ring. The material is selected from carbon steel, tungsten steel, KS steel and the like.

On the other hand, since the displacer 15 is provided with spherical guides 32, 32, such as ball bearings, in a groove 31 formed along the circumferential direction on the side facing the bottom, for example, a magnetic field or a gravitational field is suddenly increased. Thus, even if the cylinder 12 is biased or hit against the cylinder 12 against an unexpected external force generated in the case where the external force fluctuates, the occurrence of damage can be prevented.

As described above, according to the present embodiment, the first magnet 27 and the second magnet 30 are provided as the seal portions 25 on the displacer 15 and the cylinder 12 facing each other, and during operation, the cryogenic state or generated state is generated. Local pressure fluctuation of the pressing force from the displacer 15 to the cylinder 12 due to the influence of the magnetic field is backed up by the attraction of the magnets 27 and 30, so that the pressing force of the seal portion 25 against the cylinder 12 is ensured. Therefore, a path (leakage) of the refrigerant gas from the gap L can be reliably prevented.

In this embodiment, the seal portion 25 provided between the displacer 15 and the cylinder 12 facing each other is constituted by the first magnet 27 and the second magnet 30, and the seal portion 25 is provided on the first magnet 27 side. Although the first seal ring 28 and the second seal ring 29 are provided, the present invention is not limited to this example. For example, as shown in FIG.
The first magnet 27 accommodated in the groove 26 of the fifth and the second magnet 30 protruding from the wall surface of the cylinder 12 may be used to secure the contact force by using the attractive force. For example, as shown in FIG. Then, the seal portion 25 is accommodated in the groove 26 of the displacer 15 and is constituted by a pair of magnets 33a and 33b which repulsively force each other in order from the inner diameter side to the outer diameter side of the groove 26, and the repulsive force is utilized. From the second seal ring 29 to the cylinder 12
May be given a pressing force.

FIG. 5 shows a second embodiment of the regenerative refrigerator according to the present invention.
It is a partial cutaway partial sectional view showing an embodiment. The first
The same components as those of the embodiment are denoted by the same reference numerals and correspond.

The regenerative refrigerator according to the present embodiment slides in and out of the cylinder 12 to form a groove 26 formed in the circumferential direction of the displacer 15 for filling the regenerator material 17 therein. A seal portion 25 in which a regenerator 34 such as a bag, a capsule or a tube filled with a liquid such as cold water, a Teflon first seal ring 28, and a two-stage Teflon second seal ring 29 are sequentially arranged. In addition, spherical guides 32 such as ball bearings are provided in a groove 31 formed on the side facing the bottom of the displacer 15.

The regenerator 34 forming the seal portion 25
During operation, for example, cold water charged in bags, capsules, tubes, or the like is used, and during operation, the volume expansion force when the inside temperature becomes 4K becomes ice, and the volume expansion force is used as the first seal ring 28, The pressure is applied as a pressing force to the wall surface of the cylinder 12 via the second seal ring 29.

As described above, in the present embodiment, the sealing portion 25
The first seal ring 28 is provided by utilizing the volume expansion force when the cold water of the cool storage 34 becomes ice.
Since the pressing force is applied to the wall surface of the cylinder 12 via the second seal ring 29, the passage of the refrigerant gas from the gap L can be reliably prevented.

In this embodiment, the displacer 15
Since the guides 32, 32,... Are provided in the grooves 31 formed along the circumferential direction on the side facing the bottom, damage can be prevented even if an unexpected external force is generated and the displacer 15 is displaced.

In this embodiment, the displacer 15
Regenerator 34, first seal ring 2 in groove 26 formed in
8, the seal portion 25 including the second seal ring 29 is provided. However, the present invention is not limited to this example. For example, as shown in FIG. 6, the grooves 35 formed in the cylinder 12 are sequentially arranged from the outer diameter side to the inner diameter side. The seal portion 25 having the above configuration may be provided.

FIG. 7 shows a third embodiment of the regenerative refrigerator according to the present invention.
It is a partial cutaway partial sectional view showing an embodiment. The first
The same components as those of the embodiment are denoted by the same reference numerals and correspond.

In the regenerative refrigerator according to the present embodiment, a seal portion 25 is provided on the cylinder 12 accommodating the displacer 15, and the seal portion 25 is formed by a spring ring 36 and a jacket 37 surrounding the spring ring 36. It is composed.

The spring ring 36 has a large linear expansion coefficient.
For example, any one of indium, copper, aluminum, gold, and silver is selected. Further, as the jacket 37, one of polyethylene, polystyrene, and elastic rubber having high elasticity is selected.

As described above, in the present embodiment, the sealing portion 25
Is constituted by a spring ring 36 and a jacket 37, and during operation, a contraction force generated in the spring ring 36 due to cold heat is applied to the displacer 15 as a pressing force, so that the path of the gap L of the refrigerant gas is reliably prevented. Can be.

In this embodiment, the seal portion 25 is composed of the spring link 36 and the outer cover 37, and the contraction force generated when the spring ring 36 contracts is given to the displacer 15 as a pressing force. For example, as shown in FIG. 8, as shown in FIG. 8, an epoxy ring piece 38 that functions as a spacer is interposed in the jacket 37 in order from the inner diameter side to the outer diameter side to form a spring ring 36. And a spring ring 3
In the contraction of 6, the generated contraction force may be applied to the displacer 15 as a pressing force.

FIG. 9 shows a fourth embodiment of the regenerative refrigerator according to the present invention.
It is a partial cutaway partial sectional view showing an embodiment. The first
The same components as those of the embodiment are denoted by the same reference numerals and correspond.

In the regenerative refrigerator according to the present embodiment, the seal portion 25 is connected to each of the displacer 15 and the cylinder 12 in the gap L between the displacer 15 and the cylinder 12 to prevent the passage of the refrigerant gas in the gap L. For example, a flexible sheet 39 made of Teflon, polyethylene, polystyrene or the like is provided.
In this case, the flexible sheet 39 sets the connection position of each of the cylinder 12 and the displacer 15 to a point E.
_{1 may} be the same height position of the point E _2, also, as shown in FIG. 10, may be individually height position of the point F ₁ and the point F _2.

The displacer 15 is desirably provided with a guide in order to prevent an accidental damage caused by contact with the cylinder 12 due to an unexpected external force.

As described above, in the present embodiment, the cylinder 12
Since the flexible sheet 39 is provided in the gap L between the gap and the displacer 15, it is possible to reliably prevent the refrigerant gas from passing through the gap L.

[0052]

As described above, in the regenerative refrigerator according to the present invention, during operation of the seal provided between the displacer housed in the cylinder and the wall surface of the cylinder, the cryogenic state or the generated magnetic field is reduced. Since the pressing means which does not cause the local fluctuation of the pressing force from the displacer to the cylinder based on the influence of the pressure is provided, it is possible to reliably prevent the refrigerant gas from passing through the gap.

Further, the regenerative refrigerator according to the present invention is provided with a means for preventing contact with the cylinder even if an unexpected external force is generated in the displacer, so that damage to the displacer due to contact with the cylinder can be ensured. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing a first embodiment of a regenerative refrigerator according to the present invention.

FIG. 2 is a partially cutaway partial cross-sectional view of the seal portion shown in FIG.

FIG. 3 is a partially cutaway partial sectional view showing a first modified example of the seal portion shown in FIG. 1;

FIG. 4 is a partially cutaway partial sectional view showing a second modified example of the seal portion shown in FIG. 1;

FIG. 5 is a partially cutaway partial sectional view showing a second embodiment of a regenerative refrigerator according to the present invention.

FIG. 6 is a partially cutaway sectional view showing a modification of the regenerative refrigerator according to the second embodiment of the present invention.

FIG. 7 is a partially cutaway partially sectional view showing a third embodiment of a regenerative refrigerator according to the present invention.

FIG. 8 is a partially cutaway sectional view showing a modification of the regenerative refrigerator according to the third embodiment of the present invention.

FIG. 9 is a partially cutaway partial sectional view showing a fourth embodiment of a regenerative refrigerator according to the present invention.

FIG. 10 is a partially cutaway partial sectional view showing a modification of the regenerative refrigerator according to the fourth embodiment of the present invention.

FIG. 11 is a partially cutaway partial sectional view showing a conventional regenerative refrigerator.

FIG. 12 is a view used to explain the behavior of a displacer in a conventional regenerative refrigerator.

FIG. 13 is a view used to explain another behavior of a displacer in a conventional regenerative refrigerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seal part 2 Cylinder 3 Cold storage material 4 Displacer 5 Groove 6 Spring ring 7 First seal ring 8 Second seal ring 10 Refrigeration generation part 11 Refrigerant gas supply / discharge part 12 Cylinder 13 Crankshaft 14 Motor 15a First displacer 15b Second displacer 16 Connecting part 17a, 17b Cold storage material 18a, 18b Valve 19 Compressor 20 Refrigerant gas supply pipe 21 Refrigerant gas return pipe 22 Inlet 23 Outlet 24a, 24b Sliding surface 25a, 25b Seal part 26 Groove 27 First magnet 28 First seal Ring 29 Second seal ring 30 Second magnet 31 Groove 32 Guide 33a, 33b Magnet 34 Regenerator 35 Groove 36 Spring ring 37 Outer jacket 38 Ring piece 39 Flexible sheet

Claims (12)

[Claims] 1. A regenerative refrigerator provided with a seal on a displacer housed in a cylinder and sliding back and forth on the wall of the cylinder, wherein the seal is mounted in a groove formed in the displacer. The first magnet, the first seal ring, and the second seal ring are arranged and arranged in order from the inner diameter side to the outer diameter side, and the second magnet is embedded in a cylinder facing the second seal ring. A regenerative refrigerator comprising a guide provided in a groove formed on the side facing the bottom of the displacer. 2. A regenerative refrigerator provided with a seal portion on a displacer housed in a cylinder and sliding back and forth on a wall surface of the cylinder, wherein the seal portion includes a first magnet mounted in a groove formed in the displacer. A regenerative refrigerator comprising a second magnet mounted on a cylinder facing the first magnet, and a guide provided in a groove formed on the side facing the bottom of the displacer. 3. A regenerative refrigerator provided with a seal portion on a displacer which is housed in a cylinder and slides back and forth on the wall surface of the cylinder, wherein the seal portion is mounted in a groove formed in the displacer, A pair of magnets having the same polarity and a second seal ring are arranged and arranged in order from the inner diameter side to the outer diameter side, while a guide is provided in a groove formed on the side facing the bottom of the displacer. Characteristic regenerative refrigerator. 4. A regenerative refrigerator provided with a seal portion on a displacer accommodated in a cylinder and sliding back and forth on the wall surface of the cylinder, wherein the seal portion is mounted in a groove formed in the displacer, In order from the inner diameter side to the outer diameter side, the regenerator, the first seal ring, the second
A regenerative refrigerator comprising a seal ring arranged and a guide provided in a groove formed on the side facing the bottom of the displacer. 5. In a regenerative refrigerator provided with a seal portion on a displacer housed in a cylinder and sliding back and forth on the wall surface of the cylinder, the seal portion is mounted in a groove formed in the cylinder, The regenerator, the first seal ring, and the second seal ring are arranged and arranged in order from the outer diameter side to the inner diameter side, and a guide is provided in a groove formed on the side facing the bottom of the displacer. Regenerative refrigerator. 6. The regenerative refrigerator according to claim 4, wherein the regenerator is a liquid filled in one of a bag, a capsule, and a tube. 7. The regenerative refrigerator according to claim 1, wherein the first seal ring and the second seal ring are both made of Teflon (registered trademark). 8. A regenerative refrigerator provided with a seal portion on a displacer which is accommodated in a cylinder and slides back and forth on a wall surface of the cylinder, wherein the seal portion is constituted by a spring ring surrounded by a jacket. And a guide is provided in a groove formed on the side facing the bottom of the displacer. 9. A regenerative refrigerator provided with a seal on a displacer housed in a cylinder, which slides on and off the wall surface of the cylinder, wherein the seal is surrounded by an outer cover, and the seal is surrounded by an inner side of the cylinder. A regenerative refrigerator comprising a ring piece and a spring ring, which are provided in the cylinder in order toward the radial side, and a guide provided in a groove formed on the side facing the bottom of the displacer. 10. A regenerative refrigerator provided with a seal portion on a displacer accommodated in a cylinder and sliding back and forth on a wall surface of the cylinder, wherein the seal portion is a flexible sheet that closes a gap between the cylinder and the displacer. A regenerative refrigerator that is formed. 11. The regenerative refrigerator according to claim 10, wherein the flexible sheet has a connection position between the cylinder and the displacer at the same height. 12. The regenerative refrigerator according to claim 10, wherein the flexible sheet is provided at a different height from the connecting position between the cylinder and the displacer.