| 摘要 |
PURPOSE:To move an operating point to a point on a reversible permeability line and to obtain the operating point which is reversible against a temperature change by a method wherein a rare earth bonded magnet which has been saturation-magnetized by using an initial magnetic field is demagnetized forcibly by a definite amount by using a demagnetization magnetic field. CONSTITUTION:The operating point of a rare earth bonded magnet 4 which has been saturation-magnetized by using an initial magnetic field H1 is situated at a point A on a demagnetization curve (a) in the figure. Then, the magnet is demagnetized forcibly by a definite amount by using a demagnetization magnetic field H2. By the demagnetization magnetic H2, the operating point is moved form A to B on the demagnetization curve (a). when the demagnetization magnetic field H2 is removed, the operating point is moved to a point (c) along a reversible permeability line (b). After the operating point has been moved, a magnetic energy product at the point C is somewhat lowered as compared with that at the point A before the demagnetization. The operating point C after the movement is moved reversibly on a permeance line (p) even against a temperature change. A good stability can be obtained against the temperature change. |
