Magnetic Refrigeration Apparatus

Abstract

A magnetic refrigeration apparatus is provided which is structured simply to implement synchronization between rotation of magnets and switching of flow paths and which is easy to adjust at the time of manufacture. The magnetic refrigeration apparatus includes a first magnet, a second magnet placed opposite to the first magnet, a rotation mechanism rotating the first and the second magnets, a magnetocaloric element filling unit interposed between the first and the second magnets and filled with a magnetic material having a magnetocaloric effect, flow paths letting a fluid pass through to exchange heat with the magnetocaloric element filling unit, and an electromagnetic valve switching the flow paths by approaching the magnetocaloric element filling unit when attracted by a leakage flux therefrom where the leakage flux is higher than a predetermined level and by being separated therefrom where the leakage flux is lower than the predetermined level.

What is claimed is: 
     
         1 . A magnetic refrigeration apparatus comprising:
 a first magnet;   a second magnet placed opposite to the first magnet;   a rotation mechanism configured to rotate the first magnet and the second magnet;   a magnetocaloric element filling unit interposed between the first magnet and the second magnet and filled with a magnetic material having a magnetocaloric effect;   a plurality of flow paths configured to let a fluid pass through to exchange heat with the magnetocaloric element filling unit; and   an electromagnetic valve configured to switch the flow paths by approaching the magnetocaloric element filling unit when attracted by a leakage flux therefrom where the leakage flux is higher than a predetermined level and by being separated therefrom where the leakage flux is lower than the predetermined level.   
     
     
         2 . The magnetic refrigeration apparatus according to  claim 1 ,
 wherein the magnetic valve includes a valve unit configured to block the flow paths, a valve unit magnetic material attracted by the leakage flux to let the valve unit approach the magnetocaloric element filling unit, and a spring configured to separate the valve unit from the magnetocaloric element filling unit.   
     
     
         3 . The magnetic refrigeration apparatus according to  claim 1 ,
 wherein the magnetocaloric element filling unit is filled with a granular magnetic material.   
     
     
         4 . The magnetic refrigeration apparatus according to  claim 1 ,
 wherein the magnetocaloric element filling unit is filled with a ferromagnetic material formed of gadolinium or a metal compound including gadolinium.   
     
     
         5 . The magnetic refrigeration apparatus according to  claim 1 ,
 wherein the magnetocaloric element filling unit has a recessed and projected structure positioned opposite to the electromagnetic valve.