Rare-earth regenerator material particles, and group of rare-earth regenerator material particles, refrigerator and measuring apparatus using the same, and method for manufacturing the same

• US 9,719,004 B2
• Filed: 06/29/2016
• Issued: 08/01/2017
• Est. Priority Date: 08/25/2009
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Materials Company Limited (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Materials Company Limited (Toshiba Corporation)
• Inventors: Fuse, Keiichi, Yamada, Katsuhiko
• Primary Examiner(s): WARTALOWICZ, PAUL A
• Application Number:
  US15/196,692
• Publication Number:
  US 20160305692A1
• Time in Patent Office: 398 Days
• Field of Search: 505162
• CPC Class Codes: B22F 9/08 by casting, e.g. through sieves or in water, by atomising or spraying using electric discharge B22F9/14
• CPC Class Codes: B22F 9/10 using centrifugal force
• CPC Class Codes: B23P 15/26 heat exchangers or the like making heat exchangers by methods covered by other subclasses B21D53/02
• CPC Class Codes: C09K 5/041 for compression-type refrigeration systems
• CPC Class Codes: C09K 5/08 Materials not undergoing a change of physical state when used C09K5/16, C09K5/20 take precedence
• CPC Class Codes: C09K 5/14 Solid materials, e.g. powdery or granular
• CPC Class Codes: C22C 2202/02 Magnetic
• CPC Class Codes: F25B 2309/003 characterised by construction or composition of the regenerator
• CPC Class Codes: F25B 2309/1415 Pulse-tube cycles characterised by regenerator details
• CPC Class Codes: F25B 9/14 characterised by the cycle used, e.g. Stirling cycle
• CPC Class Codes: F25B 9/145 pulse-tube cycle
• CPC Class Codes: G01R 33/3804 Additional hardware for cooling or heating of the magnet assembly, for housing a cooled or heated part of the magnet assembly or for temperature control of the magnet assembly
• CPC Class Codes: G01R 33/3815 with superconducting coils, e.g. power supply therefor
• CPC Class Codes: H01F 1/015 Metals or alloys
• CPC Class Codes: Y10T 428/12014 having metal particles

Abstract

Provided is a group of rare-earth regenerator material particles having an average particle size of 0.01 to 3 mm, wherein the proportion of particles having a ratio of a long diameter to a short diameter of 2 or less is 90% or more by number, and the proportion of particles having a depressed portion having a length of 1/10 to ½ of a circumferential length on a particle surface is 30% or more by number. By forming the depressed portion on the surface of the regenerator material particles, it is possible to increase permeability of an operating medium gas and a contact surface area with the operating medium gas.

Claims

1. A refrigerator comprising at least one regenerator container into which a group of rare-earth regenerator material particles is packed, and He gas as an operating medium gas,

wherein the group of rare-earth regenerator material particles packed in the regenerator container has an average particle size of 0.045 to 3 mm, a proportion of particles having a ratio of a long diameter to a short diameter of 2 or less is 90% or more by number, and a proportion of particles having a depressed portion having a length of 1/10 to ½

of a particle circumferential length on a particle surface is 30% or more by number and the depressed portion has a depth of 1/10 or less of a particle diameter.

2. The refrigerator according to claim 1, wherein the regenerator container comprises two or more stages of regenerator material-filled zones through a mesh material.

3. The refrigerator according to claim 2, wherein the mesh material of the regenerator comprises of copper or copper alloy.

4. The refrigerator according to claim 1, wherein the regenerator comprises:

a compressor for compressing the He gas;

an expansion unit for expanding the compressed He gas; and

a regenerator unit (cold accumulating unit) for keeping the He gas cooled in the expansion unit in the cooled state.

5. The refrigerator according to claim 4, wherein the refrigerator is a GM refrigerator.

6. The refrigerator according to claim 1, wherein the rare-earth regenerator material particles are composed of at least one selected from Nd, Er₃Ni, and HoCu₂.

7. The refrigerator according to claim 1, wherein the regenerator comprises two or more of the regenerator containers connected to each other.

8. The refrigerator according to claim 1, wherein the refrigerator is a pulse tube refrigerator.