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

Patent metadata

Field	Value
Publication number	US-9719004-B2
Application number	US-201615196692-A
Country	US
Kind code	B2
Filing date	Jun 29, 2016
Priority date	Aug 25, 2009
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

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.

First claim

The invention claimed is:

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, Er 3 Ni, and HoCu 2 .

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.

Assignees

• Toshiba Kk
• Toshiba Materials Co Ltd

Inventors

• Yamada Katsuhiko
• Fuse Keiichi

Classifications

• C22C2202/02

  Magnetic · CPC title

• C09K5/14

  Solid materials, e.g. powdery or granular · CPC title

• F25B9/14

  characterised by the cycle used, e.g. Stirling cycle · CPC title

• Y10T428/12014

  having metal particles · CPC title

• C09K5/041

  for compression-type refrigeration systems · CPC title