Patent ID: 9719004
Date: 2017-08-01
CPC Classifications: B22F,B23P,C09K,C22C,F25B,G01R,H01F,Y10T

Claim:
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.