| 摘要 |
PURPOSE:To reduce the space of an elevator passage by installing a superconductive coil, exciting device for supplying a permanent electric current into the superconductive coil, and balance weight shifting coils which are divided arranged in the vertical direction oppositely to the superconductive coil. CONSTITUTION:When a starting instruction is inputted, a contactor 28 is closed, and an electric power source 27a supplies electric power into a superconductive flat coil 28 through a diode bridge 24. Then, a magnetic flux in the horizontal direction shown by the arrow is generated, and even if the contactor 28 is opened, a permanent electric current flows which returns through the diode bridge 24 flows in a superconductive coil 23, and the magnetic flux is prevented from diminish. When electricity is supplied into a shifting coil 21 set oppositely to the superconductive flat coil 23 by a thyristor switch 29, a force in the verti cal direction is generated by the electric current and magnetic flux, and shifts a balance weight 6. The rise and lowering of the balance weight 6 are carried out by switching the direction of the electric current which flows in the shifting coil 21 by selecting the thyristor switch 29. |
