| 摘要 |
PURPOSE:To sufficiency suppress vibration even if the number of revolutions agrees with a dangerous speed by varying a current applied to an electromagnet which is provided in the inner peripheral part of a dynamic damper body in such a way that it is not brought int contact with a rotary shaft in accordance with the magnitude of the vibration of the rotary shaft. CONSTITUTION:In a variable speed rotary machine in which the rotating speed of a rotary shaft can be optionally varied, if, e.g., its operating speed reached a dangerous speed, the magnitude of the vibration of the rotary shaft 1 is measured by rotary-shaft displacement sensors 10, 11. And, a magnetic resiliency for reducing the magnitude of the vibration is operated by an arithmetic device 12 based on the measured values and the operated result is sent to a controlling power source 13, from which a current having the optimum magnitude for minimizing the magnetic resiliency is made flow to electromagnets provided on the inner peripheral part of the body of a dynamic damper 5. Thereby, the vibration of the rotary shaft 1 can be automatically suppressed. |
