| 摘要 |
PURPOSE:To alleviate the load of a power source by controlling an exciting current flowed to an electromagnet so that the normal value becomes zero irrespective of an external force applied to a conveying vehicle. CONSTITUTION:A conveying vehicle 22 levitates on a guide rail 22 by a magnetic attraction force produced between a magnetic supporting unit 23 placed on the vehicle 22 and a guide rail 21. A linear induction motor 25 is composed of a conductor plate 26 secured through a support plate 24 to the lower surface of the vehicle 22 and a stator 28 secured to a base. The unit 23 has electromagnetic coils 38, 39 and a permanent magnet 40. A controller controls to flow the exciting currents of the magnets 38, 39 in transient state on the basis of the outputs of a gap sensor 51 and a current detector or to become zero irrespective of the presence of the external force in the normal state. |
