Thermo-magnetic cycle apparatus

Abstract

A vehicle air-conditioner has a magneto-caloric effect type heat pump apparatus (MHP apparatus). MHP apparatus has a magneto-caloric element (MCE element) which generates heat dissipation and heat absorption in response to strength change of an external magnetic field. The MCE element can demonstrate high performance when an element temperature is in a highly efficient temperature zone. A controller has an initial control part which adjusts the element temperature so that the element temperature approaches to the highly efficient temperature zone when the MHP apparatus is in an initial state in which the temperature is out of the highly efficient temperature zone. Thereby, starting of MHP apparatus is promoted. The initial control part may activate an auxiliary apparatus. The auxiliary apparatus heats or cools a part or all of the MCE elements.

What is claimed is: 
     
         1 . A thermo-magnetic cycle apparatus comprising:
 a magneto-caloric element which generates heat dissipation and heat absorption in response to strength change of an external magnetic field;   a magnetic field modulating device which modulates an external magnetic field applied to the magneto-caloric element;   a heat transporting device which flows heat transport medium for performing heat exchange with the magneto-caloric element so that a high temperature end and a low temperature end are generated on the magneto-caloric element; and   a controller which controls the magnetic field modulating device and the heat transporting device, wherein   the magneto-caloric element demonstrates high performance when an element temperature of the magneto-caloric element is in a highly efficient temperature zone, and wherein   the controller comprises:   an initial control part which adjusts the element temperature of the magneto-caloric element so that the element temperature approaches to the highly efficient temperature zone when the magneto-caloric element is in an initial state in which the element temperature is out of the highly efficient temperature zone; and   a regular control part which controls the magnetic field modulating device and the heat transporting device after adjustment of the element temperature by the initial control part is performed.   
     
     
         2 . The thermo-magnetic cycle apparatus in  claim 1 , wherein
 the initial control part adjusts the element temperature of the magneto-caloric element so that at least a temperature of a part of the magneto-caloric element reaches to the highly efficient temperature zone.   
     
     
         3 . The thermo-magnetic cycle apparatus in  claim 2 , wherein
 the initial control part adjusts the element temperature of the magneto-caloric element so that a temperature on the high temperature end of the magneto-caloric element reaches to the highly efficient temperature zone.   
     
     
         4 . The thermo-magnetic cycle apparatus in  claim 2 , wherein
 the initial control part adjusts the element temperature of the magneto-caloric element so that a temperature on the low temperature end of the magneto-caloric element reaches to the highly efficient temperature zone.   
     
     
         5 . The thermo-magnetic cycle apparatus in  claim 2 , wherein
 the initial control part adjusts the element temperature of the magneto-caloric element so that a temperature on a middle temperature portion between the high temperature end and the low temperature end of the magneto-caloric element reaches to the highly efficient temperature zone.   
     
     
         6 . The thermo-magnetic cycle apparatus in  claim 2 , wherein
 the magnetic field modulating device has a permanent magnet which provides the external magnetic field, and wherein   the initial control part adjusts the element temperature of the magneto-caloric element so that demagnetization of the permanent magnet is reduced.   
     
     
         7 . The thermo-magnetic cycle apparatus in  claim 1 , further comprising:
 a thermal device which uses temperature obtained on the low temperature end or the high temperature end; and   an auxiliary apparatus, which is provided differently from the thermal device, and which adjusts the element temperature of a part or all of the magneto-caloric element, wherein   the initial control part adjusts the element temperature by activating the auxiliary apparatus.   
     
     
         8 . The thermo-magnetic cycle apparatus in  claim 7 , wherein
 the auxiliary apparatus has a heater which heats the magneto-caloric element.   
     
     
         9 . The thermo-magnetic cycle apparatus in  claim 7 , wherein
 the auxiliary apparatus has a cooler which cools the magneto-caloric element.   
     
     
         10 . The thermo-magnetic cycle apparatus in  claim 7 , wherein
 the auxiliary apparatus has a thermal storage which stores the temperature obtained on the high temperature end or the low temperature end.   
     
     
         11 . The thermo-magnetic cycle apparatus in  claim 1 , further comprising:
 a heat exchange device which performs heat exchange between the auxiliary apparatus and the magneto-caloric element.   
     
     
         12 . The thermo-magnetic cycle apparatus in  claim 11 , wherein
 the heat exchange device includes a heat exchanger which performs heat exchange with the heat transport medium.   
     
     
         13 . The thermo-magnetic cycle apparatus in  claim 12 , wherein
 the heat exchanger is disposed on a member which defines a passage through which the heat transport medium flows or a member which accommodates the magneto-caloric element.   
     
     
         14 . The thermo-magnetic cycle apparatus in  claim 11 , wherein
 the thermal device includes a heat exchanger which performs heat exchange between a primary medium which is the heat transport medium and a secondary medium, and wherein   the heat exchange device includes a heat exchanger which performs heat exchange with the secondary medium.   
     
     
         15 . The thermo-magnetic cycle apparatus in  claim 12 , wherein
 the thermal device includes a valve system which takes out a part of the heat transport medium, and wherein   The heat exchanger includes a heat exchanger which performs heat exchange with the heat transport medium taken out via the valve system.   
     
     
         16 . The thermo-magnetic cycle apparatus in  claim 2 , wherein
 the initial control part controls the magnetic field modulating device and the heat transporting device to provide an initial operation condition which generates heat greater than that in the regular operation condition provided when the magnetic field modulating device and the heat transporting device are controlled by the regular control part.   
     
     
         17 . The thermo-magnetic cycle apparatus in  claim 1 , further comprising:
 a bypass device which provides flow of the heat transport medium so that the heat transport medium bypasses a part of the magneto-caloric element, wherein   the initial control part adjusts the element temperature by flowing the heat transport medium so that the heat transport medium bypasses a part of the magneto-caloric element by the bypass device.   
     
     
         18 . The thermo-magnetic cycle apparatus in  claim 1 , wherein
 the highly efficient temperature zone is a temperature zone in which the magneto-caloric element can generate a predetermined temperature difference between the high temperature end and the low temperature end by overcoming a thermal load by using an own magneto-caloric effect.   
     
     
         19 . The thermo-magnetic cycle apparatus in  claim 1 , wherein
 the magneto-caloric element includes a plurality of element units which have different magneto-caloric effects.   
     
     
         20 . The thermo-magnetic cycle apparatus in  claim 19 , wherein
 the element units are arranged to place one element unit on a position closer to the high temperature end than the other element unit, the one element unit demonstrates a magneto-caloric effect at a temperature which is higher than a temperature where the other element unit demonstrates a magneto-caloric effect.   
     
     
         21 . A thermo-magnetic cycle apparatus comprising:
 a magneto-caloric element which generates heat dissipation and heat absorption in response to strength change of an external magnetic field;   a magnetic field modulating device which modulates an external magnetic field applied to the magneto-caloric element;   a heat transporting device which flows heat transport medium for performing heat exchange with the magneto-caloric element so that a high temperature end and a low temperature end are generated on the magneto-caloric element; and   a controller which controls the magnetic field modulating device and the heat transporting device, wherein   the controller comprises:   an initial control part which adjusts a temperature of the magneto-caloric element so that a predetermined temperature difference is acquired between the high temperature end and the low temperature end; and   a regular control part which controls the magnetic field modulating device and the heat transporting device after adjustment of the element temperature by the initial control part is performed.   
     
     
         22 . The thermo-magnetic cycle apparatus in  claim 21 , wherein
 the magneto-caloric element includes a plurality of element units which have different magneto-caloric effects.   
     
     
         23 . The thermo-magnetic cycle apparatus in  claim 22 , wherein
 the element units are arranged to place one element unit on a position closer to the high temperature end than the other element unit, the one element unit demonstrates a magneto-caloric effect at a temperature which is higher than a temperature where the other element unit demonstrates a magneto-caloric effect.