| 摘要 |
PURPOSE:To realize expansion of diameter of a rotary shaft by forming each electromagnet encircling said shaft with three poles and making the width of circumferential direction for the central pole twice as large as that of the poles on both sides and further nearly equalizing the radial width of a rotoring to that of the poles of both sides. CONSTITUTION:An electromagnet 1 is formed by three poles in such a manner as loops of its magnetic flux are arranged in a raw, and the width ds1 of a central pole 11 is twice the width ds2 of poles 12 on both sides, while the width dr1 of a rotoring 3 is equal to the width ds2 of the poles 12 on both sides. In a magnetic bearing of such a structure, load capacity of the bearing is nearly proportioned to the product of the thickness ds1 of the central pole of the electromagnet and an axial length L of a rotoring. Accordingly, designing on the basis of the same load capacity enables reduction of a radial width of the rotoring to 1/2 in comparison with the formula in the past, therefore, a rotary shaft can be made larger in diameter correspondingly to the above mentioned extent of reduction. Thus, high speed rotation is realized by raising proper frequency. |
