초록 ▼

A magnetic refrigerator has a rotating magnetic wheel which includes a stack of spaced rings of magnetic material. Heat transfer plates of a high temperature heat extractor are interleaved with the magnetic rings and extend to a solid heat transfer conduit which leads to a high temperature terminal.

A magnetic refrigerator has a rotating magnetic wheel which includes a stack of spaced rings of magnetic material. Heat transfer plates of a high temperature heat extractor are interleaved with the magnetic rings and extend to a solid heat transfer conduit which leads to a high temperature terminal. Superconducting magnet coils are mounted to provide a magnetic field through the magnetic wheel at the position of the high temperature heat transfer plates. Low temperature extractor heat transfer plates are positioned outside of the magnetic field and interleave with the rings of the magnetic wheel to transfer heat thereto which is conducted from a low temperature terminal through a solid conduit. As the magnetic wheel is rotated, heat is drawn from a load and conducted through the solid material of the low temperature heat extractor to the magnetic wheel, is released when the material of the wheel is subjected to the magnetic field and transferred to the high temperature heat transfer plates, and is then conducted through the solid material of the heat transfer conduit to the high temperature terminal. Helium gas is sealed in the space surrounding the rotating magnetic wheel to transfer heat between the rings of the wheel and the heat transfer plates. Substantially all heat transfer in the magnetic refrigerator is thus provided by conduction through a solid, allowing start-up of the refrigerator without an initial charge of liquid helium to cool the refrigerator to cryogenic operating temperatures.

대표청구항 ▼

Magnetic refrigeration apparatus comprising: (a) magnetic material which exhibits the magnetocaloric effect mounted for movement; (b) means for producing a magnetic field at a position over a portion of the magnetic material such that each point of the magnetic material can be moved into and out of

Magnetic refrigeration apparatus comprising: (a) magnetic material which exhibits the magnetocaloric effect mounted for movement; (b) means for producing a magnetic field at a position over a portion of the magnetic material such that each point of the magnetic material can be moved into and out of the magnetic field as the material is moved; (c) a high temperature heat extractor including a solid conductive heat transfer conduit extending to form a continuous conductive path from a heat transfer plate adjacent to the portion of the magnetic material in the magnetic field to a high temperature interface terminal; (d) a low temperature heat extractor including a solid conductive heat transfer conduit extending to form a continuous conductive path from a heat transfer plate adjacent to the magnetic material at a position outside of the magnetic field to a low temperature interface terminal; and (e) means for containing a heat transfer gas in the space between the magnetic material and the heat transfer plates such that heat is transferred from the heat transfer plate of the low temperature extractor to the magnetic material through the gas and heat is transferred from the magnetic materal through the gas to the heat transfer plate of the high temperature extractor conduit.