Heat transfer system using thermally-operated, heat-conducting valves
Wheel-type magnetic refrigerator
Reciprocating magnetic refrigerator employing tandem porous matrices within a reciprocating displacer
Rotary magnetic heat pump
Magnetocaloric monostable and bistable inductors for electrical energy and refrigeration
Thermoelectric generator and magnetic energy storage unit
Reciprocating active magnetic regenerator refrigeration apparatus
Magnetic refrigerator Patent #: 6446441
ApplicationNo. 127080 filed on 04/19/2002
US Classes:62/3.1, USING ELECTRICAL OR MAGNETIC EFFECT62/335PLURAL PAIRED DIFFERENT FUNCTION REFRIGERATION PRODUCING ELEMENTS, E.G., CASCADE
ExaminersPrimary: Doerrler, William C.
Attorney, Agent or Firm
International ClassesF25B 021/00
AbstractApparatus and methods for performing switching of heat flow in magnetic refrigeration systems are provided. In one embodiment, microelectromechanical (MEM) switches are provided for switching from a heat absorption phase and a heat rejection phase of a magnetic refrigeration cycle. In other embodiments, these MEM switches are replaced by thermoelectric switches. The thermoelectric switches operate such that an "on" state is defined as heat flow being allowed by virtue of the thermal conductivity of the thermoelectric switch. An "off" state is defined as a net zero heat flow through the thermoelectric switch obtained by providing a current that is just sufficient to offset the heat flow through the thermoelectric switch due to its thermal conductivity. In some embodiments, the thermoelectric switches are "directly coupled" thermoelectric switches, meaning that they are energized by a direct electrical coupling to a current source. In other embodiments, one or more of the thermoelectric switches are "inductively coupled" thermoelectric switches, meaning that they are energized indirectly by a magnetic coupling. The magnetic refrigeration system may be cascaded or paralleled to provide greater cooling.