TW386107B - Magnetic hold-over material for extremely low temperature and refrigerator using the same - Google Patents

Abstract

The present invention relates a magnetic hold-over material for extremely low temperature, forming by magnetic hold-over material particles. The percentage of the damaged particles is lower than 1w.t.% when the magnetic hold-over material particles are applied with single vibration 1x10<6>, having maximum acceleration 300 m/s<2>. This magnetic hold-over material for extremely low temperature demonstrates excellent mechanical property when subject to mechanical vibration or acceleration. A refrigerator is a hole-over constituted by a hole-over container filled with the above magnetic hold-over material for extremely low temperature. A refrigerator like this can demonstrate excellent refrigerating property for a long term.

Description

A7 B7

Amended in October 88, Patent Application No. 85102070, Revised Chinese Manual 5. V. INTRODUCTION TO THE INVENTION (ίο) Freezing performance is stable for a long time. In addition, since the MR I device, the cryopump, the magnetic levitation speeding train, and the magnetic field-applied single crystal pull-up device all control the performance of each device of the refrigerator, the MRI device of the present invention such as the refrigerator described above is used. Cryogenic pumps, magnetic levitation speeding trains, and magnetic field application type single crystal pull-up devices can all exert their excellent performance for a long time. [Brief Description of the Drawings] FIG. 1 is a cross-sectional view showing an example of a vibration test container used in the reliability evaluation test of the magnetic cold storage material granules used in the present invention. The relationship between the filling of the container for the vibration test of the granular body and the filling rate and the ratio of the particles destroyed by the vibration test. Fig. 3 is a diagram of the main part of the GM refrigerator made by an embodiment of the present invention. Fig. 4 shows FIG. 5 is a diagram showing a schematic structure of a superconducting MR I device according to an embodiment of the present invention. FIG. 5 is a diagram showing a schematic structure of a main part of a magnetic levitation speeding train according to an embodiment of the present invention, and FIG. 6 is a schematic structure of a cryopump according to an embodiment of the present invention. FIG. 7 is a schematic diagram of a schematic configuration of a magnetic field application type single crystal pull-up device according to an embodiment of the present invention. [Explanation of Drawing No.] 1 ... Vibration test container 1 3 ... Vacuum container 1 0 ... GM freezer 1 4 ... 1st regenerator 1 1 ... 1st cylinder 1 5 ... 2nd regenerator 1 2 ... 2nd cylinder 1 6, 1 7… Seal ring This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (Please read the precautions on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -13-A7 B7 V. Description of the Invention (1) [Technical Field] The present invention relates to a cryogenic cold storage material used in a refrigerator and a refrigerator using the same. [Background Art] In recent years, the development of superconductor technology has been remarkable. With the expansion of its application field, it is indispensable to develop small and low-performance refrigerators. Such a refrigerator is required to be lightweight, small, and thermally efficient. For example, a ‘superconductor MR device’ or a cryopump is a refrigerator using a freeze cycle such as the Grford macphon method (’GM method) or the Sterling method. In addition, the maglev speeding train also requires a high-performance cold 'freezer, and some single-crystal pull-up devices also use a high-performance freezer. In such a freezer, an operating medium such as compressed helium gas is flowed in one direction * in a regenerator filled with the cold storage material, and the heat energy is supplied to the cold storage material, and the expanded operating medium flows in the opposite direction. , And receive thermal energy to supply cold storage materials. In this process, as the reheating effect becomes good, printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling this page), the thermal efficiency of the operating medium cycle will be improved, and lower temperatures can be achieved 〇 As a cold storage material used in the above-mentioned refrigerator, copper or lead is mainly used. However, since this kind of cold storage material is extremely low due to the extremely low temperature below 20 K, its specific heat will be significantly reduced. The use of Er3Ni, ErNi, ErNi2 and other Er-Ni intermetallic compounds is under review. (Refer to Japanese Patent Application Laid-Open No. 1-3 1 0269) or RRh-based intermetallic compounds (R: Sm, Gd, Tb, Dy, Ho, etc.) This paper is applicable to China National Standard (CNS) A4. 210X297 mm) -4-8 ^ .1¾2¾ 5. Description of the invention (11) A7 B7 1 8. •• 1st cold storage r. Material 5 4… baffle 1 9. •. 2nd cold storage material 5 5… ring 2 0 .. 1st expansion chamber 6 0… magnetic field application type single crystal pull-up device 2 1. •• 2nd expansion chamber 6 1… single crystal pull-up 2 2 · •. Compressor 6 2… superconductor coil 3 0 · .. Superconducting device Μ RI device 6 3 · .. Lifting mechanism 3 1 · •. Superconductor static magnetic field coil 6 4. •. Freezer 3 2 · • • Inclined magnetic field wire network. Loop 6 5 ·. • Current wire 3 3 .. probe for radio wave transmission and reception 6 6 · .. heat Shield 3 4 ··· Freezer 6 7 ··· Helium Container 3 5 ·· Cryogenic Thermostat 3 6 ··· Radiation Adiabatic Shielding 4 0 · • · Magnetic Superconductor Magnet for Super Speed Trains Cooperative printed 4 1 ... Superconductor wire 圏 4 2 ... Liquid helium tank 4 3 ... Liquid nitrogen tank 4 4 ... Freezer 4 5 ... Laminated septa 4 6 ... Power wires 4 7 ... Permanent current switch 5 0 ... Cryogenic pump 5 1… Cryogenic pump 5 2… Freezer 5 3… Standard for shielding private paper Applicable to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)

14-Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A7 ______B7_____ V. Description of Invention (2)

Er, Tm, Yb, etc.) (Refer to Japanese Patent Publication No. 51-52378) and other magnetic cold storage materials. However, under the operating state of the refrigerating machine described above, the operating medium for helium gas flows at high pressure and high speed to make it flow. The direction can be changed frequently, and the gap between the cold storage materials filled in the cooler is used. To this end, various forces such as mechanical vibration will be applied to the cold storage material. Furthermore, a refrigerator such as a maglev speeding train or artificial For satellites, etc., large accelerations will be exerted on the cold storage material.-As such, for the various types of forces acting on the cold storage material, the above-mentioned magnetic cold storage materials formed by intermetallic compounds such as Er3Ni or ErRh are generally brittle materials. Mechanical vibration, acceleration, etc. during operation become a cause and there is a problem that it becomes micronization. The occurrence of fine powders impedes airtightness, etc., and it will adversely affect the performance of the cooler, which will reduce the capacity of the refrigerator. An object of the present invention is to provide a refrigerating material for extremely low temperature that is superior to mechanical properties such as mechanical vibration or acceleration, and a refrigerating machine capable of exhibiting superior long-term refrigeration performance by using that refrigerating material. The MR I device, cryopump, maglev speeding train, and magnetic field application or single crystal pull-up device that can perform silly performance for a long time due to the use of such a freezer is provided. [Disclosure of the invention] The cold storage material for extremely low temperature of the present invention is a cold storage material for extremely low temperature with magnetic cold storage material granules, which is characterized in that: the above-mentioned magnetic cold storage material granules are composed of Chinese national standard (CNS) A4 Specifications (210X297mm) ----- ^ ---: --Φ-- (Please read the precautions on the back before filling out this page) Order-1. A7 B7 month 5 supplementary description of the invention (12) [Mode for Carrying Out the Invention] The present invention will be described below according to embodiments. (Please read the precautions on the back before filling in this page). Example 1 and Comparative Example 1 First 'E 3N i master alloy was made using high frequency. The E r sN i was melted at approximately 1 2 6 3 K, and the molten slurry was dropped on a rotating disk in an argon environment (pressure = about 80 kPa) for rapid cooling and solidification. The obtained granules were subjected to shape classification and screening, and spherical particles having a particle size of 1 80 to 250 # ιη were selected. This process was repeated to obtain 10 batches of spherical Er 3 Ni granules. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs and then 'Er 3 N i particles were randomly extracted from the spherical E r3N i granules of the above 10 batches and filled in the vibration test container 1 shown in FIG. 1 respectively. (D = .l 5mm, h = l 4mm). In the vibration tester, a single vibration with a maximum acceleration of 30 Om / s 2 was applied for 1 X 10 times. The appropriate shape after the test was classified and screened to determine the ratio of the spherical Er 3N i particles that were destroyed. The particle ratio (destruction rate) destroyed by each batch is shown in Table 1. It is clear from Table 1 that each spherical E r3N i granule of the sample No. 1 to N 〇8 is equivalent to each spherical E r3Ni granule of the sample No. 1 to No. 9 to N 0 1. In Comparative Example 1. Here, the filling rate in the container 1 for vibration test of Er3Ni particles was changed in the range of 5 5 to 6 6%, and the lowest failure rate was used as the failure rate of the batch. Figure 2 shows the filling rate and vibration test of the spherical Er 3N i particle vibration container for the sample Ν ο 1 and the vibration test. The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm)-15- Printed by A7 B7_____ of the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 5. Among the magnetic cold storage material particles of the description of the invention (3), a maximum acceleration of 30 Om / s2 is applied to the magnetic cold storage material particles. 1 X 1〇 The ratio of the magnetic regenerator particles that will break at β is 1% by weight or less. Furthermore, the refrigerator of the present invention is characterized by being provided with a regenerator and an extremely low-temperature device having the above-mentioned invention filled in the above-mentioned cold storage container. Cooler for cold storage materials. In addition, the MR I (magnetic resonance ·

Imaging) device, cryopump, magnetic levitation speeding train, and magnetic field application type single crystal crystal pull-up device, all of which have the above-mentioned refrigerator of the present invention. 0 The cold storage material for extremely low temperature of the present invention is made of magnetic cold storage material. However, it is made of aggregates (groups) of magnetic cold storage material particles. Examples of the magnetic cold storage materials used in the present invention include, for example, the general formula; RMz ... (l) (where R is a formula from Y, La, Ce, Pr, Nd, Pm * Sm »Eu, Gd» Tb, Dy »Ho» Er »at least one rare earth element selected by Tm and Yb, M represents at least one metal element selected by Ni, Co, Cu, .Ag, A1 and Ru, z The numbers in the range of 001 to 9.0 are the same. The following are the same.) The intermetallic compounds containing rare earth elements, or the general formula: RRh ..... (2) This standard is common to China Standard (CNS) A4 specification (210X297 mm) '': ~ (诮 Please read the precautions on the back before filling in this page)

A7 B7 5. The relationship between the destruction rate of invention description (13). In Figure 2, the filling rate is 63.7% and the destruction rate is 0 (below the detection limit). Therefore, this value will become the destruction rate of this batch. According to the above, no test has been done above this filling rate. Each batch of magnetic regenerative material spherical granules formed by the above-mentioned E r3N i was filled in a regenerative container with a filling rate of 63. 5 ~ 63 · 8%, and the regenerators were respectively manufactured, and the structures of these regenerators are shown in The 2-stage GM refrigerator in Fig. 3 is separately installed as the second-stage regenerator (second regenerator 15), and a refrigeration test is performed. The results are shown in Table 1 together. From the table, it is clear that using a refrigerator with magnetic regenerative material granules whose particles are destroyed when the single vibration with a maximum acceleration of 3,000 m / S2 is applied for 1 X 10 s times, can be used for a long period of time. To maintain excellent freezing capacity. . (Please read the notes on the back before filling out this page). The consumer cooperation of the Intellectual Property Bureau of the Ministry of Economic Affairs has printed this paper to apply the national standard (CNS) A4 specification (210 X 297 mm), „16 1. Printed by A7 B7, Shellfish Consumer Cooperative, Central Bureau of Standards, Ministry of Economic Affairs. 5. Intermetallic compounds containing rare earth elements indicated in the description of the invention (4). Omm 的 的 冷冷 材。 In a spherical shape, the flow of gas can become smooth. • By these things, the magnetic cold storage material particles (total particles) of 70% by weight or more, from a particle size of 0. 0 1 ~ 3. Omm range of magnetic cold storage material The particle composition is better. If the particle size of the magnetic regenerator particles is less than 0.0 mm, the filling density becomes too high, and the pressure loss of the working medium such as helium may increase. On the one hand, if the particle size exceeds 3.0 mm, the heat transfer area between the magnetic storage cold material particles and the moving medium will become smaller, and the heat transfer efficiency will decrease. Therefore, if such particles exceed the magnetic cold storage material particles, At 30% by weight 01 ~ 3. The risk of lowering the cold storage performance, etc. • A better particle size is in the range of 0. 0 5 to 2. 0 mm, and even more preferably in the range of 0.1 to 0.5 mm. The particle size is in the range of 0.01 to 3. The ratio of particles in the range of 0 mm to the magnetic cold storage material granules is more preferably 80% by weight or more, and more preferably 90% by weight. The cold storage material for extremely low temperature of the present invention is the magnetic cold storage material particles as described above. When the group added a single vibration with a maximum acceleration of 300 m / s2 plus 1 X 1 0 β times, the ratio of the damaged magnetic cold storage material particles was made of magnetic cold storage material particles of 1% by weight or less. The invention is that the mechanical strength of each magnetic regenerator particle is the amount of nitrogen or carbon of impurities, and there is a complicated relationship between the cooling rate, metal structure, and shape during the solidification process, and if it is a group, it will pay attention to the magnetic properties of stress concentration Those who have the mechanical strength of cold storage material particles • Groups of magnetic cold storage material particles such as this, for example, the maximum acceleration applied to the magnetic cold storage material particles is 30 Om / s 2 This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) {Please (Please read the notes on the back before filling this page) Order A7 B7 V. Description of Invention (β) Table 1

Sample No. printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Particle Destruction Rate (wt%) using Vibration Test Freezing Capacity (W) Initial value 7 0 0 0 Example 1 1 0 * 0. 34 0.33 2 0.41 0.35 0 28 3 0.02 0.35 0.32 4 0 氺 0.34 0.34 5 0.76 0.36 0.26 6 0.5 5 0.35 0.25 7 0.03 0.35 0. 33 8 0.25 0.36 0.29 Comparative Example 1 9 1.59 0.34 0.07 10 2.17 0.36 0.04 (Please read the precautions on the back first (Fill in this page). Assembling: ·-, 'r This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ~ Π Printed by A7 B7______, a consumer cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs Explanation (5) When the single vibration is 1 X 1 ο β times, the reliability of the mechanical strength of the magnetic cold storage material particles can be evaluated by measuring the ratio of the particles destroyed. That is, if a single vibration with a maximum acceleration of 30 Om / s2 for 1 X 1 0β times is applied to the magnetic cold material granules, when the ratio of the destroyed particles is 1% by weight, the manufacturing batch of the magnetic cold material granules In addition, even if the manufacturing conditions are different, there is almost no micronized magnetic cold storage material particles due to mechanical vibration during the operation of the freezer or the acceleration of the system's motion when the freezer is installed. Therefore, the use of This kind of mechanical cold storage granules can prevent the airtightness of the refrigerator. When the maximum acceleration applied to the magnetic cold storage material granules is a single vibration of 1 × 10β times of 30 Om / s2, the ratio of the damaged magnetic cold storage material particles is less than 0.5% halo, and more preferably 0.1 weight. Below gray. Therefore, when the maximum acceleration of the above-mentioned vibration test (acceleration test) is less than 30 Om / s2, most of the particles of the magnetic cold storage material will not be destroyed, so the reliability cannot be evaluated. When the maximum acceleration applied to the cold storage material granules is less than 1 X 10 β times with a single vibration of 30 Om / s2, due to the system motion carried by the freezer, the acceleration on the magnetic cold storage material granules cannot be fully evaluated. Practical reliability. The conditions of the above-mentioned vibration test of the present invention are important. By changing the maximum acceleration and the number of vibrations of the single vibration into the above-mentioned values, the reliability of the actual use conditions of the magnetic cold storage material granules can be evaluated. Reliability evaluation is when single vibration with maximum acceleration of 4 0 Om / s2 is applied for 1 XI 〇β times, or maximum acceleration of 3 0 0 is applied. This paper size applies Chinese National Standard (CNS) Α4 specification (210X297 mm) {Please read the back first (Notes to fill in this page)

, tT &quot; -8-B7 V. Description of the invention (25) * Er N i is the magnetic cold storage material on the low temperature side. (Please read the precautions on the back before filling this page) The following describes the embodiments of the MR I device, maglev speeding train, cryopump, and magnetic field application type single crystal pull-up device of the present invention. Fig. 4 is a diagram showing a schematic configuration of a superconducting MRI device to which the present invention is applied. The superconductor MR I device 30 shown in the figure is a superconductor static magnetic field coil 31 that applies a stable static magnetic field to the human body space at a uniform time, which corrects the non-uniformity of the generated magnetic field and omits the correction coil shown in the figure. A gradient magnetic field coil 32, which gives a magnetic field gradient in the measurement field, and a 'radio wave transmitting / receiving probe 33', etc. As the cooling device for the superconducting static magnetic field coil 31, the refrigerator 34 of the present invention as described above is used. According to the figure, 35 series cryostats, 3 6 series radiation insulation are used. "Using the refrigerator 3 of the present invention 4 is used in the superconductor MR I device 3 0 'is to set the operating temperature of the superconductor static magnetic field coil 3 1 to be long. Time can ensure stability, so a static magnetic field that is uniform in space and long in time can be obtained. ’Therefore, the performance of the superconductor M R I device 30 can be long, and the stability can be exerted during the printing of the consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. Fig. 5 is a diagram showing a schematic configuration of a main part of a maglev speeding train to which the present invention is applied, and shows a part of a superconducting magnet 40 for a maglev speeding train. The superconductor magnet 40 for the maglev super-speed train shown in the figure is composed of a superconductor coil 41, which cools the liquid helium tank 42 of the superconductor coil 41, and prevents the liquid nitrogen tank 43, which emits liquid helium, and the freezing of the present invention. Machine 4 4 and so on. According to the figure, 4 5 series of laminated insulation materials, 4 6 series of power wires' 4 7 ^ paper size applies to the national standard of China (CNS) A4 (210 X 297 mm) &quot; -28-Central Standard of the Ministry of Economic Affairs Printed by the Consumer Cooperative of the Bureau A7 B7 V. Description of the invention (6) When the single vibration of m / s2 is 1 × 107, the ratio of the damaged magnetic cold storage material particles is preferably 1% by weight or less. The reliability evaluation test (vibration test) of the above-mentioned magnetic cold storage material granules is performed as follows. • First, a certain amount of magnetism is randomly extracted from the magnetic cold storage material granules with a particle size as a predetermined range according to each batch Cooling material particles. Next, as shown in Fig. 1, the extracted magnetic cold storage material granules were filled in a cylindrical container 1 for a vibration test, and a single vibration with a maximum acceleration of 300 m / s2 was applied 1x10e times. The cylindrical container 1 used for the vibration test is made of alumite or the like. After the vibration test, the magnetic regenerator particles destroyed by the sieve are sorted or classified according to shape, etc., and the reliability of the magnetic regenerator particles group is evaluated by measuring its weight. -Therefore, the density (filling rate) of the magnetic cold storage material particles filled in the vibration test container depends on the shape and particle size distribution of the magnetic cold storage material particles. However, if the filling ratio is too low, the test will be conducted. In the container, there is a free space where the particles of the magnetic cold storage material can move, and the vibration resistance of the magnetic cold storage material particles cannot be accurately evaluated. On the other hand, if the filling rate is set too high, the magnetic cold storage material is filled. The particles must be pressed into the test container, and the possibility of damage due to the compression force at that time becomes higher. Therefore, it is necessary to perform a test of a large change in the filling rate. That is, in the present invention, the ratio of the magnetic cold storage material particles damaged by vibration is tested for various changes in one batch, and among them, the Destroyed magnetism: The ratio of the particles of the cold storage material is the lowest value to be used as the measured value. "The I standard of this paper applies the Chinese National Standard (CNS) A4 specification (210X297 mm) ~~ 1 ~ {Please read the back first Please note this page and fill in this page) L®. Order printed by the Consumer Standards Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7_ _ V. Description of the invention (7) The cold storage material for extremely low temperature of the present invention, if it meets the reliability evaluation test described above (Vibration test) Although it is not limited to its composition or shape, etc., it is preferable to satisfy the following conditions for the concentration and shape of impurities in particles due to mechanical vibration or acceleration, which is one of the causes of particle destruction. 0 (a ) In the state of being processed into a particle shape, the amount of nitrogen as an impurity in the particles of the magnetic cold storage material is set to 0.3% by weight. (B) In the state of being processed into a particle shape, as The carbon content of the impurities in the magnetic regenerator particles was set to 0.1% by weight. (c) Consider the surrounding length of the projected image of each particle constituting the magnetic regenerative granular material as L, and when the actual area of the projected image is regarded as A, it will exceed / L2 / 4; the shape factor R represented by rA exceeds 1 The presence ratio of 5 particles is set to 5% or less. That is, nitrogen and carbon, which are impurities in the magnetic regenerator particles, deposit rare earth nitrides or rare earth carbides at the crystal grain boundaries of the magnetic regenerator material expressed by the above formula (1) or (2). , And it will become a factor that reduces the mechanical strength of the magnetic regenerator particles. In other words, by reducing the amount of nitrogen and carbon, good mechanical strength can be obtained stably, and good reproducibility can be obtained, which can satisfy the reliability evaluation test (vibration test). For this reason, the nitrogen content of the impurities in the magnetic regenerator particles is preferably 0.3% by weight or less, and the carbon content is preferably 0.1% by weight or less. 05 重量 ％ 之间。 The amount of nitrogen as an impurity is preferably 0.1% by weight or less, more preferably 0.05% by weight or less. In addition, the carbon content as an impurity is preferably 0.05% by weight or less, and more preferably 0.02% by weight. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (2 丨 0X297). ~ ~- 10-— 一; —— Γ: | _0II (Please read the notes on the back before filling in this page) Order Λ A7 ___ B7 _____ ^ 5. Description of the invention (8) The following. In addition, the shape of the magnetic cold storage material particles is preferably spherical as described above, and its sphericity is higher and the surface is smoother. It will make the gas flow more smooth. At the same time, it can suppress the mechanical properties of the magnetic cold storage material particles. Great stress concentration during vibration and other periods. This makes it possible to increase the mechanical strength of the magnetic regenerator particles. That is, particles with more complicated surface shapes such as protrusions on the particle surface are more likely to be subjected to stress concentration when the magnetic regenerator particles are under power, and the mechanical strength of the magnetic regenerator particles will be adversely affected. 'Therefore, the surrounding length of the projection image of each particle constituting the magnetic regenerative material granular body is regarded as L, and when the actual area of the projection image is regarded as A, the shape factor R represented by L 2/4 π A exceeds 1.5 particles The existence ratio is preferably 5% or less. For example, the shape factor R is, for example, randomly extracted more than 100 particles according to the manufacturing batch of each magnetic cold storage material particle, and it is better to evaluate these by image processing. If the number of particles extracted is too small, the shape factor R of the entire magnetic cold storage material particles may not be properly evaluated. · Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs (please read the notes on the back before filling this page) The above-mentioned shape factor R is a large value (partially deformed) when there are protrusions on the surface even when the particles are highly spherical. On the other hand, if the surface is smoother, the shape factor R becomes lower even for particles with slightly lower sphericity. In this way, the shape factor R tends to become large when there are protrusions on the surface. That is, the smaller the shape factor R, it means that the particle surface is smoother (partial circularity is small). It is a valid parameter for the evaluation of the partial shape. Therefore, if this form factor R exceeds 1.5, the paper's size is applied to the Chinese National Standard (CNS) A4 specification (210X297 mm) by using the particle ratio of the paper. -11-Printed by the Consumers' Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs Crack A7 B7 V. Description of the invention (9) When it is less than 5%, the mechanical strength of the magnetic cold storage material particles can be improved. The presence ratio of particles having a shape factor R exceeding 1.5 is preferably 2% or less, more preferably 1% or less, and V is more preferable if the existence ratio of particles having a shape factor R exceeding 1.3 is 15% or less. The presence ratio of particles having a form factor R exceeding 1.3 is preferably 10% or less, and more preferably 5% or less. As mentioned above, the manufacturing method of the magnetic cold storage material granules is not particularly limited, but various manufacturing methods can be applied. For example, the predetermined molten slurry can be applied by centrifugal spray method, gas spray method, rotary electrode method, etc. Method to make it rapidly condensed and solidified * In this case, using nitrogen-purified raw materials, or reducing the amount of impurities in the environment during the rapid condensation, can reduce the amount of nitrogen and carbon in the particles of magnetic regenerator material. Further, for example, by performing shape classification according to the optimization of manufacturing conditions or the tilting vibration method, it is possible to obtain magnetic regenerative material granules having an existing ratio of particles having a shape factor R exceeding 1.3 of 15% or less. The refrigerating machine of the present invention is used as a cold storage material for extremely low temperature filled in a cold storage container, and has a magnetic cold storage granule with the above-mentioned mechanical characteristics, that is, a single vibration with a maximum acceleration of 300 m / s2 is applied. 1 X 1 〇βtimes, there is a regenerator that uses magnetic regenerator material granules with a broken particle ratio of 1% by weight or less. The extremely low-temperature cold storage material used in the refrigerator of the present invention has almost no micronized magnetic cold storage material particles due to the mechanical vibration during the operation of the refrigerator or the acceleration of the motion of the system mounted on the refrigerator as described above. Therefore, it will not cause the airtightness of the refrigerator and the like. Therefore, the paper size can be applied to the Chinese National Standard (CNS) A4 specification (210 × 297). -----: --- L-^ ------ order ----- ^-1 , — (Please fill in this page with the notes on the back) -12-A7 B7

Amended in October 88, Patent Application No. 85102070, Revised Chinese Manual 5. V. INTRODUCTION TO THE INVENTION (ίο) Freezing performance is stable for a long time. In addition, since the MR I device, the cryopump, the magnetic levitation speeding train, and the magnetic field-applied single crystal pull-up device all control the performance of each device of the refrigerator, the MRI device of the present invention such as the refrigerator described above is used. Cryogenic pumps, magnetic levitation speeding trains, and magnetic field application type single crystal pull-up devices can all exert their excellent performance for a long time. [Brief Description of the Drawings] FIG. 1 is a cross-sectional view showing an example of a vibration test container used in the reliability evaluation test of the magnetic cold storage material granules used in the present invention, and FIG. 2 is a view showing a magnetic cold storage material according to an embodiment of the present invention. The relationship between the filling of the container for the vibration test of the granular body and the filling rate and the ratio of the particles destroyed by the vibration test. Fig. 3 is a diagram of the main part of the GM refrigerator made by an embodiment of the present invention. Fig. 4 shows FIG. 5 is a diagram showing a schematic structure of a superconducting MR I device according to an embodiment of the present invention. FIG. 5 is a diagram showing a schematic structure of a main part of a magnetic levitation speeding train according to an embodiment of the present invention, and FIG. 6 is a schematic structure of a cryopump according to an embodiment of the present invention. FIG. 7 is a schematic diagram of a schematic configuration of a magnetic field application type single crystal pull-up device according to an embodiment of the present invention. [Explanation of Drawing No.] 1 ... Vibration test container 1 3 ... Vacuum container 1 0 ... GM freezer 1 4 ... 1st regenerator 1 1 ... 1st cylinder 1 5 ... 2nd regenerator 1 2 ... 2nd cylinder 1 6, 1 7… Seal ring This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (Please read the precautions on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -13-8 ^ .1¾2¾ 5. Description of the invention (11) A7 B7 1 8. •• 1st cold storage r. Material 5 4… baffle 1 9. •. 2nd cold storage material 5 5… ring 2 0 ... 1st expansion chamber 6 0… magnetic field application type single crystal pull-up device 2 1. •• 2nd expansion chamber 6 1… single crystal pull-up 2 2 · •. Compressor 6 2… superconductor coil 3 0 · .. superconductor Pieces MR device 6 3 · .. Lifting mechanism 3 1 · ·. Superconductor static magnetic field coil 6 4 · ·. Freezer 3 2 · · • Inclined magnetic field wire network. Loop 6 5 ·. • Current wire 3 3 .. Probes for radio wave transmitting and receiving 6 6 · .. heat shield 3 4 ··· Freezer 6 7 ··· Helium Container 3 5 ·· Cryogenic Thermostat 3 6 ··· Radiation Adiabatic Shielding 4 0 · •• Superconducting Magnets for Maglev Speeding Trains Printed by Employees ’Cooperatives of Intellectual Property Bureau of the Ministry of Economic Affairs System 4 1 ... Superconductor wire 4 2 ... Liquid helium tank 4 3 ... Liquid nitrogen tank 4 4 ... Freezer 4 5 ... Laminated septa 4 6 ... Power line 4 7 ... Permanent current switch 5 0 ... Cryogenic pump 5 1 … Cryogenic pump 5 2… Freezer 5 3… The size of the shielding private paper is applicable to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)

14-A7 Month B7 Supplement V. Description of the Invention (12) [Forms of Implementing the Invention] The present invention will be described below according to embodiments. (Please read the precautions on the back before filling in this page). Example 1 and Comparative Example 1 First 'E 3N i master alloy was made using high frequency. The E r sN i was melted at approximately 1 2 6 3 K, and the molten slurry was dropped on a rotating disk in an argon environment (pressure = about 80 kPa) for rapid cooling and solidification. The obtained granules were subjected to shape classification and screening, and spherical particles having a particle size of 1 80 to 250 # ιη were selected. This process was repeated to obtain 10 batches of spherical Er 3 Ni granules. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs and then 'Er 3 N i particles were randomly extracted from the spherical E r3N i granules of the above 10 batches and filled in the vibration test container 1 shown in FIG. 1 respectively. (D = .l 5mm, h = l 4mm). In the vibration tester, a single vibration with a maximum acceleration of 30 Om / s 2 was applied for 1 X 10 times. The appropriate shape after the test was classified and screened to determine the ratio of the spherical Er 3N i particles that were destroyed. The particle ratio (destruction rate) destroyed by each batch is shown in Table 1. It is clear from Table 1 that each spherical E r3N i granule of the sample No. 1 to N 〇8 is equivalent to each spherical E r3Ni granule of the sample No. 1 to No. 9 to N 0 1. In Comparative Example 1. Here, the filling rate in the container 1 for vibration test of Er3Ni particles was changed in the range of 5 5 to 6 6%, and the lowest failure rate was used as the failure rate of the batch. Figure 2 shows the filling rate and vibration test of the container for spherical E r3N i granule vibration test of the sample Ν ο 1. The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm)-15-

A7 B7 5. The relationship between the destruction rate of invention description (13). In Figure 2, the filling rate is 63.7% and the destruction rate is 0 (below the detection limit). Therefore, this value will become the destruction rate of this batch. According to the above, no test has been done above this filling rate. Each batch of magnetic regenerative material spherical granules formed by the above-mentioned E r3N i was filled in a regenerative container with a filling rate of 63. 5 ~ 63 · 8%, and the regenerators were respectively manufactured, and the structures of these regenerators are shown in The 2-stage GM refrigerator in Fig. 3 is separately installed as the second-stage regenerator (second regenerator 15), and a refrigeration test is performed. The results are shown in Table 1 together. From the table, it is clear that using a refrigerator with magnetic regenerative material granules whose particles are destroyed when the single vibration with a maximum acceleration of 3,000 m / S2 is applied for 1 X 10 s times, can be used for a long period of time. To maintain excellent freezing capacity. . (Please read the notes on the back before filling out this page). The consumer cooperation of the Intellectual Property Bureau of the Ministry of Economic Affairs has printed this paper to apply the national standard (CNS) A4 specification (210 X 297 mm), „16 First A7 B7 V. Description of Invention (β) Table 1

Sample No. printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Particle Destruction Rate (wt%) using Vibration Test Freezing Capacity (W) Initial value 7 0 0 0 Example 1 1 0 * 0. 34 0.33 2 0.41 0.35 0 28 3 0.02 0.35 0.32 4 0 氺 0.34 0.34 5 0.76 0.36 0.26 6 0.5 5 0.35 0.25 7 0.03 0.35 0. 33 8 0.25 0.36 0.29 Comparative Example 1 9 1.59 0.34 0.07 10 2.17 0.36 0.04 (Please read the precautions on the back first (Fill in this page). Assembling: ·-, 'r This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ~ Π Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7_______ 5. DESCRIPTION OF THE INVENTION (15) *: The detection limit is 0.01% by weight or less as 0. As shown in the circle, the 2-stage GM freezer 10 shown in circle 3 is an embodiment of the freezer of the present invention. The two-stage GM refrigerator 10 shown in FIG. 3 is provided with a first cylinder 11 having a large diameter, and a vacuum container 13 connected to the first cylinder 11 and a second cylinder 12 having a small coaxial diameter. A first regenerator 14 is arranged freely in the first cylinder 11. Seals 16 and 17 are arranged between the first cylinder 11 and the first regenerator 14 respectively. The first regenerator 14 is a first regenerator 18 containing a copper mesh. The second cold accumulator 15 contains the extremely low temperature cold storage material of the present invention as the second cold storage material 19. The first cold accumulator 14 and the second cold accumulator 15 are respectively provided with passages of an operating medium such as helium gas as a gap between the first cold storage material 18 or the extremely low temperature cold storage material 19. A first expansion chamber 20 is installed in the second and second regenerators 15 and 15 of the first and second regenerators 14 and 14. A second expansion film chamber 21 is provided between the second regenerator 15 and the front end wall of the second cylinder 12. A first cooling stage 22 is formed at the bottom of the first expansion chamber 20. The second expansion chamber 2 1 has a low-temperature second cooling stage 2 3 formed by the first cooling stage 2 2 at the bottom. In the GM refrigerator 10 of the two-stage type described above, a high-pressure working medium is supplied from the compressor 2 4 ( For example, helium gas) · The supplied operating medium reaches the first expansion chamber 20 by being stored in the first 18 cold storage materials of the first cold storage 14 and is stored in the cold storage for the extremely low temperature of the second cold storage 15 19 (the second cold storage material) to reach the second expansion chamber 2 1 · This paper size applies the Chinese National Standard (CNS) A4 specification (2 丨 OX297) 犮 II .—— Γ__rl # ------ -Order ------- li.: R {Please read the notes on the back before filling in this page) -18-A7 B7 V. Description of the invention (16) In the case of the operating medium, the cold storage materials supply heat energy and apply it. Cooling • Each of the cooling stages 2 2 '2 3 is cooled by the operating medium between each of the cold storage materials 18 and 19' expanding in each expansion chamber 20, 21 to cause cold '. The expanded working medium is flowing in the opposite direction between each of the cold storage materials 1 8 '19 * The working medium is discharged after receiving the thermal energy from each of the cold storage materials 1 8' 19 "As it becomes a reheating effect in this process When it becomes good, the thermal efficiency of the operating medium cycle is improved, and a lower temperature can be achieved. Example 2: Comparative Example 2 A HoCu2 master alloy was produced by high-frequency melting. The HoCu2 master alloy was melted at about 1 323K, and the molten slurry was dropped on a rotating disc in an argon atmosphere (pressure = about 8 O k P a) to perform rapid condensation. The granules were obtained by selecting and sieving * After adjusting the particle size to the range of 18 0 ~ 2 5 0 # m, the shape classification using the tilting vibration method was performed, and 1 kg of spherical granules were selected. This process was performed multiple times, and Five batches of spherical HoCu2 were obtained. Here, according to the conditions of shape classification, such as adjusting the tilt angle, vibration intensity, etc., each batch of balls was printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs (please Read the precautions on the back before filling out this poverty) tr κ riti status. __ Next, randomly extract 300 particles from these 5 batches of spherical Η 〇C u2 granules, and the surrounding length L of the projected image of each particle and the actual area A of the projected image are processed using image processing. The shape factor R represented by L2 / 4; r A was measured. In addition, the vibration test was performed for each batch in the same manner as in the first actual beer example, and the ratio of the broken spherical Η 〇C u2 particles was determined. The shape factor R and vibration of each batch are applied to the Chinese country. Standard (CNS) A4 specification (210X297 mm) -19-A7 B7 V. Description of the invention (17) The destruction rate of the tested particles is shown in Table 2 · It can be clear from Table 2 that the sample No. ο 1 ~ N 〇4 Each spherical Η0C u2 granular body corresponds to Example 2, and each spherical Η0C granular body corresponds to Comparative Example 2. From each of the above-mentioned Η 〇C u 2 batches of 4 magnetic cold storage material spheroidal granules, were filled in the low-temperature side 1/2 of the cold storage container at a filling rate of 63.5 ~ 64. 0%, and at 髙After the warm side 1/2 was filled with a shot, a two-stage GM freezer was installed as a second-stage regenerator in the same manner as in the embodiment, and the same freezing test as in Example 1 was performed. The results are shown in Table 2 together. (Please read the precautions on the back before filling out this page) Order Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs This paper applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -20-

7 B V. Description of the invention (18) Table 2 Particle ratio of printed sample No R &gt; 1.5 at the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs (¾) Particle failure rate (wt%) using vibration test Freezing capacity ( ff) Initial value after 70,000 hours' Example 2 1 0.3 0.08 0.53 0.53 2 1. .3 0.26 0.59 0.56 3 4.2 0.54 0.5 2 0.45 4 2.5 0.39 0.57 0.52 Comparative Example 2 5 7.4 1.74 0.5 1 0.18 {Please read first (Notes on the back, please fill out this page) L ..

、 1T This paper size applies the Chinese National Standard (CNS) A4 specification (210X297mm) -21-A7 B7 V. Description of the invention (ig) It can be clear from Table 2 that the maximum acceleration is 300m / s2 The ratio of the soil-damaged particles when vibrating for 1 X 1 0β times is a refrigerator using magnetic regenerative material granules of 1% by weight or less, and it is known that they can maintain excellent freezing capacity for a long period of time. In Example 3 and Comparative Example 3, E r N i 0.eC was prepared by high-frequency melting. .:. With master alloy. This ErNi0.eCoO.i master alloy was melted at about 1523 K, and the molten slurry was dropped on a turning disk in an argon environment (pressure = about 80 k Pa) to perform rapid condensation. The granules obtained by sieving were selected for proper shape classification and sieving, and spherical and granules with a particle size of 1 80 ~ 2 5 0 // m were selected. 1 kg. Processes like this were performed several times, and 5 batches of spherical ErNio. ^ Co were obtained. .. Printed by the Consumers' Cooperative of the Central Bureau of Economics (please read the precautions on the back before filling this page) Here, due to the batch of raw materials when making the master alloy, the vacuum of the environment during high-frequency melting, the impurities in the solidification process are rapidly condensed The amount of gas and the like are different, so the amount of nitrogen and carbon in the spherical particles will be different. The nitrogen and carbon contents in the spherical particles are shown in Table 3. For these 5 batches of spherical E r N i O.0C o. The granular body was subjected to a vibration test in the same manner as in Example 1, and the ratio of the spherical spherical Er Ni 0.eC on particles was determined. The nitrogen content and carbon content of each batch are shown in Table 3 according to the particle destruction rate of the vibration test. It is clear from Table 3 that each spherical E r N i 〇.eC o of the sample No. 1 to No. 4 . ^ The granules are spherical E r Ni i 0.0C0 equivalent to Example 3 and sample No 05. The grain system corresponds to the comparative example. This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 male dragon) 22 A7 B7 V. Description of the invention (20) The batches of magnetic regenerative materials will be made from the above batches of Ε ΓΝ i 〇.eC 〇ο.ι The granules are respectively filled at the low temperature side 1/2 of the cold storage container with a filling rate of 63. 4 ~ 64. 0%, and after the high temperature side 1/2 is filled with a lead shot, the same is done in the 2-stage GM freezer as in Example 1. The second stage regenerator was installed, and a freezing test was performed in the same manner as in Example 1. The results are shown together in Table 3. (Read the precautions on the back before you fill in this page.) The paper size printed by the Central Standards Bureau of the Ministry of Economic Affairs and the Consumer Cooperatives is printed on paper that applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -23-B7 V. Description of the invention ( 2l) Table 3 Sample No. printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs Impurity content Particle breakage rate using vibration test (wt%) Freezing capacity (W) Initial value 70 000 hours Nitrogen and carbon Example 3 1 0 .02 0. 01 0. 02 0. 68 0. 67 2 0.22 0. 02 0. 06 0. 62 0.59 3 0. 06 0.04 0. 33 0.67 0.61 4 0. 12 0. 07 0. 79 0. 61 0 50 Comparative Example 3 5 0.35 0. 15 1.31 0.67 0. 24 -----: --- L —— # 1 — (Jingxian read the precautions on the back of the book before filling out this page) The size of the paper is applicable to China National Standard (CNS) A4 specification (210X297 mm) -24-A7 ________B7_____ V. Description of the invention (22) It is clear from Table 3 that a single vibration with a maximum acceleration of 3 0 Om / 's 2 is applied 1 X 1 〇β The ratio of particles destroyed at the next time is a frozen body using magnetic regenerative material granules of less than 1% by weight. Maintain excellent freezing ability. In Example 4, Comparative Example 4 E r N i master alloys were prepared from high-frequency melting,

Er3Co master alloy, ErCu master alloy, Ηο 2Α1 master alloy. These master alloys were melted at about 1 4 3 3 K, and the molten slurry was dropped on a rotating disc in an argon atmosphere (pressure = about 80 k P a) to perform rapid condensation. The granules obtained by sieving were selected for appropriate shape classification and sieving / and 1 kg of spherical granules having a particle diameter of 180 to 250 // m were selected. Processes like this were performed several times, and 5 batches of spheroids were obtained. Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs (please read the precautions on the back before filling this page). For each batch of these spheroids, a vibration test was performed in the same manner as in Example 1 to determine the failure rate. The batch with the lowest destruction rate (example) and the batch with the highest damage (comparative example) were selected. For each of these batches, analysis was performed to determine the shape factor R and nitrogen and carbon. The results are shown below. -Install each of the above-mentioned magnetic regenerator spherical granules in a freezer as follows. • First, fill the magnetic regenerator spherical granules formed by Erni with a filling rate of 63.2 to 64.0% in the cold storage container. The low temperature side 1/2 is filled with the magnetic regenerative material spherical granules formed by Er 3Co, Er Cu, or Ho2A 1 at a filling rate of 63. 0 to 6 4. The same as in the embodiment, the Chinese paper standard (CNS) A4 size (210X297 mm) A7 _ B7 ____ is applied to the two paper sizes of this paper. V. Description of the invention (23) The GM freezer is installed as the second stage cooler. The same freezing test as in Example 1 was performed. The results are printed together in Table 4 printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs (please read the precautions on the back before filling out this page) This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) -26-

A

7 B Printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 5. Description of the invention (24) Table 4 Composition of high-temperature-side magnetic cold storage material * R &gt; 1.5 Particle ratio at 5⑻ Impurity (wt%) Particles using vibration test Destruction rate (wt%) Freezing capacity (W) Initial value 7000 hours after gaseous carbon Example 4 Εγ3〇ο 4. 1 0. 01 0. 01 0. 07 0.57 0. 50 ErCu 0. 5 0. 24 0. 05 0. 18 0. 67 0. 61 HozAl 1. 2 0. 02 0. 01 0.29 0. 60 0. 60 Comparative Example 4 Er 3C0 6. 5 0. 08 0. 04 1.41 0. 52 0. 13 ErCu 0 8 0. 32 0. 14 1.52 0.66 0.26 Η02ΑΙ 5. 8 0.35 0. 13 2.45 0.57 0. 07 (Please read the precautions on the back before filling out this page) This paper size applies the Chinese National Standard (CNS) A4 specification ( 210X297mm) -27-B7 V. Description of the Invention (25) * Er Ni is the magnetic cold storage material on the low temperature side. (Please read the precautions on the back before filling this page) The following describes the embodiments of the MR I device, maglev speeding train, cryopump, and magnetic field application type single crystal pull-up device of the present invention. Fig. 4 is a diagram showing a schematic configuration of a superconducting MRI device to which the present invention is applied. The superconductor MR I device 30 shown in the figure is a superconductor static magnetic field coil 31 that applies a stable static magnetic field to the human body space at a uniform time, which corrects the non-uniformity of the generated magnetic field and omits the correction coil shown in the figure. A gradient magnetic field coil 32, which gives a magnetic field gradient in the measurement field, and a 'radio wave transmitting / receiving probe 33', etc. As the cooling device for the superconducting static magnetic field coil 31, the refrigerator 34 of the present invention as described above is used. According to the figure, 35 series cryostats, 3 6 series radiation insulation are used. "Using the refrigerator 3 of the present invention 4 is used in the superconductor MR I device 3 0 'is to set the operating temperature of the superconductor static magnetic field coil 3 1 to be long. Time can ensure stability, so a static magnetic field that is uniform in space and long in time can be obtained. ’Therefore, the performance of the superconductor M R I device 30 can be long, and the stability can be exerted during the printing of the consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. Fig. 5 is a diagram showing a schematic configuration of a main part of a maglev speeding train to which the present invention is applied, and shows a part of a superconducting magnet 40 for a maglev speeding train. The superconductor magnet 40 for the maglev super-speed train shown in the figure is composed of a superconductor coil 41, which cools the liquid helium tank 42 of the superconductor coil 41, and prevents the liquid nitrogen tank 43, which emits liquid helium, and the freezing of the present invention. Machine 4 4 and so on. According to the figure, 4 5 series of laminated insulation materials, 4 6 series of power wires' 4 7 ^ paper size applies to the national standard of China (CNS) A4 (210 X 297 mm) &quot; -28-Central Standard of the Ministry of Economic Affairs A7 B7 _______ printed by the Bureau ’s Consumer Cooperatives V. Invention Description (26) is a permanent current switch. Since the superconductor magnet 40 of the maglev superspeed train using the freezer 44 of the present invention can maintain the operating temperature of the superconductor coil 41 for a long period of time, the magnetic levitation and propulsion of the train are stabilized for a long period of time. In particular, acceleration is applied to a superconducting magnet 40 for a magnetic levitation speeding train. However, the freezer 44 of the present invention can maintain excellent refrigeration ability for a long period of time when it is subjected to acceleration. Therefore, it greatly contributes to the strength of magnetic field strength and the like. During the stabilization. Therefore, using this superconducting magnet .40 maglev speeding train, it can show its reliability for a long time. Fig. 6 is a diagram showing a schematic configuration of a cryopump to which the present invention is applied. The cryopump 50 shown in the figure is a cryopump pump 51 made by condensing gas molecules or adsorption. The cryopump 51 is cooled to the refrigerating machine 52 of the present invention at a predetermined extremely low temperature, and is installed here. The interval 5 3 is composed of a baffle 5 4 provided at the suction port and a ring 5 5 which changes the exhaust velocity of argon, nitrogen, hydrogen, and the like. By using the cryopump 50 of the refrigerator 52 of the present invention, the temperature of the rail of the cryopal panel 51 can be kept stable for a long period of time. Therefore, the performance of the cryopump 50 can be exhibited for a long period of time. Fig. 7 is a diagram showing a schematic configuration of a magnetic field application type single crystal pull-up device to which the present invention is applied. The magnetic field application type single crystal pull-up device 60 series shown in the figure, a raw material melting crucible, a heater, a single crystal pull-up portion 61 with a single crystal pull-up mechanism, etc., and a superconductor coil 6 that applies a static magnetic field to the raw material melt. And it is composed of a single crystal pulling mechanism 63 for pulling the upper part 61. In addition, for the cooling of the superconductor coil 62, use the above paper size as applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) (锖 Please read the precautions on the back before filling in this page)

-29-A 7 B7____ V. Description of the invention (27) The freezer 6 4 of the present invention. According to the figure, 6 5 series current wires, 6 6 series thermal shielding plates, 67 series helium containers · The single crystal pull-up device 60 using the freezer 64 of the present invention can ensure a stable and stable operating temperature for a long period of time Therefore, a good magnetic field that suppresses the convection of the raw material melt of the single crystal can be obtained. Therefore, the performance of the single crystal can be pulled up to the device 60 to maintain stability for a long period of time. [Industrial Applicability] From the above examples, it is clear that if the cold storage material for extremely low temperature according to the present invention has excellent reproducibility of mechanical characteristics such as mechanical vibration or acceleration. Therefore, if the refrigerating machine of the present invention is used as the cold storage material for extremely low temperature, it is possible to maintain excellent repeatability of the refrigerating performance for a long period of time. In addition, the MR I device of the present invention having such a refrigerator, a cryopump, a magnetic levitation speeding train, and a magnetic field application type single crystal pull-up device can exhibit excellent performance for a long period of time. (Please read the note on the back first Please fill in this page for further details.) The paper size printed by the Employees' Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs applies the Chinese National Standard (CNS) A4 (210X297 mm) -30-

Claims (1)

Consumers' cooperation with the Intellectual Property Bureau of the Ministry of Economic Affairs, Du Duan or Huo B8 ____.. --___ D8 ^ '-' -Ssaasai n iunf VI. Patent Application No. 8 5 1 02070 Chinese Patent Application Amendment of the Republic of China 1988 1 October correction 1. A kind of cold storage material for extremely low temperature belongs to a category with: General formula: R Μ z (where 'R system is represented by γ, La, Ce, Pr, Nd , Pm ·, Sm 'Eu' Gd, Tb, Dy, Ho, .Er, .Tm., And .Yb selected at least i kinds of rare earth elements, m series. Is represented by Ni, C0, Cu, A g, A 1 and Ru selected at least one type of metal element · ζ represents a number in the range of 0 0 0 1 to 9 · 〇) or '-general formula: RR h (where R represents A rare earth element selected by Y, La, Ce, Pr., Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Y b, μ represents Ni, C 〇, ^ cu 'A g' A 丄-and at least one metal element selected by Ru) 'means a magnetic cold storage material, granules containing an intermetallic compound of # ± elements, and can achieve extremely low temperatures below 70 K Cold storage material for extremely low temperature ' It is characterized in that among the magnetic cold-storage material particles constituting the magnetic cold-storage material particles, the magnetic-storage cold-storage material particles are destroyed when a single vibration with a maximum acceleration of 3000 m / s2 is applied for 1x 1 0β times. The ratio of the magnetic regenerator particles is 1% by weight or less. 2. The cold storage material for extremely low temperature as described in item 1 of the scope of the patent application, wherein the nitrogen content of the magnetic cold storage material particle system is 0.3% by weight to τ °. This paper standard is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) (Please read the note on the back of the dream page and fill in the lettuce page) Pack ---- Order ----------, 1 Consumers' cooperation with the Intellectual Property Bureau of the Ministry of Economic Affairs, Du Duan or Huo B8 ____.. --___ D8 ^ '-' -Ssaasai n iunf VI. Patent Application No. 8 5 1 02070 Chinese Patent Application Amendment of the Republic of China 1988 1 October correction 1. A kind of cold storage material for extremely low temperature belongs to a category with: General formula: R Μ z (where 'R system is represented by γ, La, Ce, Pr, Nd , Pm ·, Sm 'Eu' Gd, Tb, Dy, Ho, .Er, .Tm., And .Yb selected at least i kinds of rare earth elements, m series. Is represented by Ni, C0, Cu, A g, A 1 and Ru selected at least one type of metal element · ζ represents a number in the range of 0 0 0 1 to 9 · 〇) or '-general formula: RR h (where R represents A rare earth element selected by Y, La, Ce, Pr., Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Y b, μ represents Ni, C 〇, ^ cu 'A g' A 丄-and at least one metal element selected by Ru) 'means a magnetic cold storage material, granules containing an intermetallic compound of # ± elements, and can achieve extremely low temperatures below 70 K Cold storage material for extremely low temperature ' It is characterized in that among the magnetic cold-storage material particles constituting the magnetic cold-storage material particles, the magnetic-storage cold-storage material particles are destroyed when a single vibration with a maximum acceleration of 3000 m / s2 is applied for 1x 1 0β times. The ratio of the magnetic regenerator particles is 1% by weight or less. 2. The cold storage material for extremely low temperature as described in item 1 of the scope of the patent application, wherein the nitrogen content of the magnetic cold storage material particle system is 0.3% by weight to τ °. This paper standard is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) (Please read the note on the back page of the dream item and fill in the lettuce page) Pack ---- Order ----------, 1 A8 B8 C8 D8 六 、 Scope of patent application 3. The cold storage material for extremely low temperature described in item i of the scope of the patent application, wherein the carbon content of the i-type cold storage material particles is 01% by weight or less. 4. The cold storage material for extremely low temperature as described in item 1 of the scope of the patent application, wherein the ratio of the magnetic cold storage material particles whose shape factor R represented by L2 / 4 π A exceeds 1-5 is 5%. the following. 5. The cold storage material for extremely low temperature as described in item 1 of the scope of the patent application, wherein the magnetic cold storage material particle system has 70% by weight or more of the magnetic cold storage material particles, and the particle size is in the range of 〇1 ~ 3. 〇mm. . 6 · —A kind of freezer 'It is a cold accumulator, and the extremely low temperature cold storage material formed by the magnetic cold storage material granules filled in the cold storage container described above. ------ Cold material, the magnetic storage cold material pellet system consists of: General formula: R Μ z (where R is represented by Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd , Tb, Dy, Ho, Er, Tm and Yb selected at least one rare earth element, M represents at least one metal element selected by Ni, Co, Cu'Ag, A1 and Ru, z represents 0. 001 ~ 9. 0) or, General formula: RR h (where R represents Y, La, Ce, Pr'Nd, Pm, Sm, Eu'Gd'Tb, D'y ' Ho, Er, Tm and Y b selected a rare earth element system ..............————-...- N- i ......... '.. Co, Cu, Ag, A 1 and at least one metal element selected by Ru) This paper is compatible with the Chinese National Standard (CNS) A4 specification (210 X 297 cm) (Please read ts &gt; it before completing this page) nnnn ϋ · 1 n One Heart '. «nnnnn I Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs-2-A8 B8 C8 __ _ D8 VI. Made of intermetallic compounds containing rare earth elements as indicated in the scope of patent applications; The extremely low-temperature cold storage material below 7 〇 K is characterized in that among the magnetic cold storage material particles constituting the magnetic cold storage material granules, there is provided a magnetic storage material for the above '.U ........ The granular body exerts a single vibration with a maximum acceleration of 30 Om / s 2 with a single vibration of 1 X 1 0, and it has been destroyed. The ratio of the upper and lower particles of the cold storage material is 1% by weight or less. Cold storage material for low temperature. 7. The refrigerator according to item 6 of the scope of patent application, wherein the nitrogen content of the magnetic regenerator particle system is 0.3% by weight or less. 8. The refrigerator according to item 6 of the scope of application for a patent, wherein the carbon content of the magnetic regenerator particle system is 0.1% by weight or less. 9. The refrigerator according to item 6 of the scope of the patent application, wherein the ratio of the magnetic regenerator particles whose shape factor R represented by L2 / 4 π A exceeds 1.5 is 5% or less. 10. The refrigerator according to item 6 of the scope of the patent application, wherein the magnetic cold storage material particle system has a particle size of more than 70% by weight of the magnetic cold storage material particles and a range of 0.01 to 3.0 mm. 1 1 ... The chiller of item 6 of the scope of patent application can be used for MR I device. 1 2. The freezer according to item 6 of the scope of patent application can be used for a cryopump. 1 3. The freezer of item 6 of the scope of patent application can be used for maglev speeding trains. 14. If the freezer of item 6 of the scope of patent application is used, it can be used for magnetic field application type single crystal pull-up device. This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (Read the precautions for wearing first before filling out this page) Order -------- Shovel-Ministry of Economic Affairs. Intellectual Property Bureau Printed by Employee Consumer Cooperatives 3