Magnetic Heat Pump Device

Abstract

A magnetic heat pump device ( 1 ) is provided with a magnetic working substance ( 13 ) having a magnetocaloric effect, magnetic working bodies ( 11 A, 11 B) in which a heat transfer medium is circulated, permanent magnets ( 6 ) changing the size of a magnetic field to be applied to the magnetic working substance, and a displacer ( 8 ) causing the heat transfer medium to reciprocate between a high-temperature end ( 14 ) and a low-temperature end ( 16 ) of the magnetic working body. The displacer ( 8 ) moves the heat transfer medium to the high-temperature end side from the low-temperature end side of the magnetic working body before the permanent magnets ( 6 ) increase the size of the magnetic field to be applied to the magnetic working substance. An improvement of efficiency is achieved by improving the timing of changing the size of the magnetic field to be applied to the magnetic working substance and the reciprocating movement of the heat transfer medium.

1 . A magnetic heat pump device comprising:
 a magnetic working body which has a magnetic working substance having a magnetocaloric effect and in which a heat transfer medium is circulated;   a magnetic field changing device changing a size of a magnetic field to be applied to the magnetic working substance;   a heat transfer medium moving device causing the heat transfer medium to reciprocate between a high-temperature end and a low-temperature end of the magnetic working body;   a heat exchanger on a heat dissipation side for causing the heat transfer medium on a side of the high-temperature end to perform heat dissipation; and   a heat exchanger on a heat absorption side for causing the heat transfer medium on a side of the low-temperature end to perform heat absorption, wherein   the heat transfer medium moving device moves the heat transfer medium to the high-temperature end side from the low-temperature end side of the magnetic working body before the magnetic field changing device increases the size of the magnetic field to be applied to the magnetic working substance.   
     
     
         2 . A magnetic heat pump device comprising:
 a magnetic working body which has a magnetic working substance having a magnetocaloric effect and in which a heat transfer medium is circulated;   a magnetic field changing device changing a size of a magnetic field to be applied to the magnetic working substance;   a heat transfer medium moving device causing the heat transfer medium to reciprocate between a high-temperature end and a low-temperature end of the magnetic working body;   a heat exchanger on a heat dissipation side for causing the heat transfer medium on a side of the high-temperature end to perform heat dissipation; and   a heat exchanger on a heat absorption side for causing the heat transfer medium on a side of the low-temperature end to perform heat absorption, wherein   the heat transfer medium moving device moves the heat transfer medium to the low-temperature end side from the high-temperature end side of the magnetic working body after the magnetic field changing device reduces the size of the magnetic field to be applied to the magnetic working substance.   
     
     
         3 . A magnetic heat pump device comprising:
 a magnetic working body which has a magnetic working substance having a magnetocaloric effect and in which a heat transfer medium is circulated;   a magnetic field changing device changing a size of a magnetic field to be applied to the magnetic working substance;   a heat transfer medium moving device causing the heat transfer medium to reciprocate between a high-temperature end and a low-temperature end of the magnetic working body;   a heat exchanger on a heat dissipation side for causing the heat transfer medium on a side of the high-temperature end to perform heat dissipation; and   a heat exchanger on a heat absorption side for causing the heat transfer medium on a side of the low-temperature end to perform heat absorption, wherein   the heat transfer medium moving device moves the heat transfer medium to the high-temperature end side from the low-temperature end side of the magnetic working body before the magnetic field changing device increases the size of the magnetic field to be applied to the magnetic working substance, and   the heat transfer medium moving device moves the heat transfer medium to the low-temperature end side from the high-temperature end side of the magnetic working body after the magnetic field changing device reduces the size of the magnetic field to be applied to the magnetic working substance.   
     
     
         4 . The magnetic heat pump device according to  claim 1 , wherein
 when time while the magnetic field changing device is increasing the size of the magnetic field to be applied to the magnetic working substance is defined as T1,   the heat transfer medium moving device moves the heat transfer medium to the high-temperature end side from the low-temperature end side of the magnetic working body before time larger than 0 and equal to or smaller than 0.15×T1 before the magnetic field changing device starts to increase the size of the magnetic field to be applied to the magnetic working substance.   
     
     
         5 . The magnetic heat pump device according to  claim 2 , wherein
 when time while the magnetic field changing device is reducing the size of the magnetic field to be applied to the magnetic working substance is defined as T2,   the heat transfer medium moving device moves the heat transfer medium to the low-temperature end side from the high-temperature end side of the magnetic working body after time equal to or larger than 0.25×T2 and equal to or smaller than 0.33×T2 after the magnetic field changing device reduced the size of the magnetic field to be applied to the magnetic working substance.   
     
     
         6 . The magnetic heat pump device according to  claim 3 , wherein
 when time while the magnetic field changing device is increasing the size of the magnetic field to be applied to the magnetic working substance is defined as T1,   the heat transfer medium moving device moves the heat transfer medium to the high-temperature end side from the low-temperature end side of the magnetic working body before time larger than 0 and equal to or smaller than 0.15×T1 before the magnetic field changing device starts to increase the size of the magnetic field to be applied to the magnetic working substance, and   when time while the magnetic field changing device is reducing the size of the magnetic field to be applied to the magnetic working substance is defined as T2,   the heat transfer medium moving device moves the heat transfer medium to the low-temperature end side from the high-temperature end side of the magnetic working body after time equal to or larger than 0.25×T2 and equal to or smaller than 0.33×T2 after the magnetic field changing device reduced the size of the magnetic field to be applied to the magnetic working substance.