The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 18, 2006
Filed:
Nov. 24, 2003
Akiko Saito, Kawasaki, JP;
Tadahiko Kobayashi, Yokohama, JP;
Takao Sawa, Yokohama, JP;
Masashi Sahashi, Yokohama, JP;
Akiko Saito, Kawasaki, JP;
Tadahiko Kobayashi, Yokohama, JP;
Takao Sawa, Yokohama, JP;
Masashi Sahashi, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
The magnetic material for magnetic refrigeration of the present invention is characterized by exhibiting, in a certain temperature region, preferably, only in part of a temperature region from 200 K to 350 K, an inflection point at which a second order differential coefficient of a magnetization curve changes from positive to negative with respect to a magnetic field, within the range of this magnetic field formed using a permanent magnet unit. This magnetic material of the present invention can generate a low temperature by using a relatively low magnetic field, by transferring the entropy between the electron spin system and the lattice system near the temperature at which an inflection point appears on the magnetization curve. Examples of the magnetic material meeting this condition are La(Fe,Si), (Hf,Ta)Fe, (Ti,Sc)Fe, and (Nb,Mo)Fe, each containing 50 to 60 atomic % of transition metals such as Fe.