초록 ▼

Apparatus 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 embodime

Apparatus 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.

대표청구항 ▼

Apparatus 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 embodime

Apparatus 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. directing a second fuel-air mixture through the pilot burner to produce a pilot flame in the combustion chamber for stabilizing the combustion of the at least a second portion of the fuel in the combustion chamber. 8. The method of claim 6, wherein the combustible fuel is a first type of fuel, and further comprising: supplying a second type of combustible fuel to the pre-heated fuel-free air until a predetermined temperature is achieved in the pre-heated fuel-free air; and terminating the supply of the second type of fuel after the predetermined temperature is achieved. 9. The method of claim 8, wherein the second type of combustible fuel comprises one of the group of hydrogen and propane. l items to be attached to the masonry wall. Each strap also engages the inner surface of the masonry wall. The straps preferably have a series of ridges that engage the cover plate such that sufficient resistance is provided to temporarily affix various objects to be embedded in the masonry wall. The straps position the plate on the front surface of the masonry wall such that it is generally concentric with the masonry hole. Grout is then poured into the hollow cavity behind the masonry wall, thus securing the embedded material permanently. The cover plate is preferably transparent to allow the user to determine that the wall and hole are property grouted.