| 摘要 |
1. Refrigerating or heat-pumping device comprising : - an element (1) of paramagnetic material, located between a cold source (3) and a hot source (2) and having an axis (22), - magnetic means (6, 7) generating a variable field in the element (1) in order to cause adiabatic demagnetization of the paramagnetic material, the magnetic field changing from a first value HA to a second value HB below the first value, and the material changing from a first temperature T1 to second temperature T2 below the first temperature, then in order to cause isothermal demagnetization of the material at the second temperature T2 , the field changing from the second value HB to a third value HC below the second value, then in order to magnetize the material adiabatically, the magnetic field, changing from the third value HC to a fourth value HD above the third value, the material changing from the second temperature T2 to the first temperature T1 , and then in order to magnetize the material isothermally at the first temperature T1 , the magnetic field changing from the fourth value HD to the first value HA , the element (1) of paramagnetic material, the cold source (3) and the hot source (2) being arranged along the axis (22), the device also possessing valves (35, 40) arranged respectively between the cold source (3) and the element of paramagnetic material and between the hot source (2) and the element (1) of paramagnetic material, these valves being closed during adiabatic demagnetization and during adiabatic magnetization, the hot valve (35) being closed and the cold valve (40) open during the isothermal demagnetization of the material, and the hot valve (35) being open and the cold valve (40) closed during the isothermal magnetization of the material, characterized in that the element of paramegnatic material has the form of a ring (21), the central axis of which forms the said axis (22) and which consists of segments (23) of paramagnetic material thermally insulated from one another, the magnetic means (27, 28, 29, 30) being located opposite at least part of the ring (21) of paramagnetic material, and of means (31, 32, 33, 34) for generating a rotational movement of the magnetic means about the said axis (22), if the ring occupies a fixed position, or for generating a rotational movement of the ring about the said axis (22), if the magnetic means occupy a fixed position, the valves (35, 40) consisting of elements of thermally insulating material which are arranged so as to be periodically opposite the ends of the segments (23) of paramagnetic material, in such a way that the segments (23) are thereby in periodic contact with the hot source and the cold source. |
