Magnetic cooling device

Abstract

A magnetic cooling device is provided, including a magnetocaloric module and a magnetic unit movably disposed around the magnetocaloric module. The magnetocaloric module comprises a bed, a first magnetocaloric member, a second magnetocaloric member, and a third magnetocaloric member received in the bed, wherein the first and third magnetocaloric members are respectively close to a cold end and a hot end of the magnetocaloric module. Specifically, the first, second, and third magnetocaloric members are arranged along a central axis of the magnetocaloric module, and the weight of the third magnetocaloric member exceeds that of the first and second magnetocaloric members. A thermal fluid sequentially flows through the first, second, and third magnetocaloric members to transfer heat from the cold end to the hot end of the magnetocaloric module.

What is claimed is: 
     
         1 . A magnetic cooling device, comprising:
 a magnetocaloric module, comprising:   a bed, forming a first opening and a second opening respectively at a cold end and a hot end of the magnetocaloric module;   a first magnetocaloric member, received in the bed and close to the first opening;   a second magnetocaloric member, received in the bed;   a third magnetocaloric member, received in the bed and close to the second opening, wherein the first, second, and third magnetocaloric members are arranged along a central axis of the magnetocaloric module, and the weight of the third magnetocaloric member exceeds that of the first and second magnetocaloric members;   a magnetic unit, disposed around the magnetocaloric module to provide different magnetic fields to the magnetocaloric module; and   a thermal fluid, sequentially flowing through the first opening, the first, second, third magnetocaloric members, and the second opening, to transfer heat from the cold end to the hot end of the magnetocaloric module.   
     
     
         2 . The magnetic cooling device as claimed in  claim 1 , wherein the second magnetocaloric member is disposed between the first and third magnetocaloric members, and the weight of the second magnetocaloric member exceeds that of the first magnetocaloric member. 
     
     
         3 . The magnetic cooling device as claimed in  claim 1 , wherein the mass ratio of the third magnetocaloric member relative to the first magnetocaloric member is from 1.1 to 2. 
     
     
         4 . The magnetic cooling device as claimed in  claim 1 , wherein the first, second, and third magnetocaloric members comprise first order magnetocaloric material, second order magnetocaloric material or alloy. 
     
     
         5 . The magnetic cooling device as claimed in  claim 1 , wherein the first, second, and third magnetocaloric members have a porosity from 30% to 50%. 
     
     
         6 . The magnetic cooling device as claimed in  claim 1 , wherein the first, second, and third magnetocaloric members comprise the same material. 
     
     
         7 . The magnetic cooling device as claimed in  claim 1 , wherein the first, second, and third magnetocaloric members comprise different materials. 
     
     
         8 . The magnetic cooling device as claimed in  claim 1 , wherein the magnetic cooling device further comprises two insulating members disposed between the first, second, and third magnetocaloric members, wherein the insulating members comprise Aerogel, POM, Teflon or porous material. 
     
     
         9 . The magnetic cooling device as claimed in  claim 1 , wherein the magnetic unit comprises a permanent magnet, electromagnet or superconductor. 
     
     
         10 . The magnetic cooling device as claimed in  claim 1 , wherein the magnetic unit is movable or rotatable relative to the magnetocaloric module.