| 摘要 |
PURPOSE:To enlarge the difference between critical and rotational speeds and to control dynamically the critical speed by adjusting appropriately the impregnation quantity of a rotary body under operation when the difference between the rotational and critical speeds is below a permissible value, or an amplitude is above the permissible value. CONSTITUTION:The relation between the critical speed and the impregnation quantity of the control medium to the rotary body, the permissible value of the difference between the rotational and critical speeds, or the permissible value of the amplitude of the rotary body are previously inputted to an impregnation quantity control part. Together with the operation start of the rotary body, the dynamic control starts, and the impregnation quantity control part grasps the current impregnation quantity of the control medium in the rotary body based on impregnation and extraction quantity signals with the rotary body being operated, calculates the difference between the critical speed and the detection value of rotational frequency, which the detection part detects, and decides whether or not it is below the permis sible value, or whether or not the amplitude is below the permissible value. Where the speed difference is below the permissible value, or the amplitude is larger than said value, the critical speed is changed to increase and decrease the quantity of the control medium in the rotary body so that the difference between the critical and rotational speeds of the rotary body can be enlarged. |
