Adjustment device of rotary machine, adjustment method of rotary machine, and manufacturing method of rotary machine

1. A device comprising:

a rotary machine including a movable base, the movable base formed in an annular shape and configured to rotate around an axis so as to enable an object to move inside the annular shape;

a vibration measuring instrument configured to, when the movable base is rotated, measure an amplitude of vibration of the rotary machine along each of the axis and a direction orthogonal to the axis; and

means for calculating a position and a weight of an adjustment weight to be provided on the movable base based on the amplitude of vibration measured by the vibration measuring instrument, so that the weight of the adjustment weight can be adjusted, and the adjustment weight can be moved along the axis, wherein the position and the weight of the adjustment weight minimize the amplitude of vibration of the movable base;

wherein the means for calculating comprises:

means for obtaining first influence wave data from a difference between first adjustment amplitude data corresponding to a rotational angular position of the movable base measured orthogonally by the vibration measuring instrument when the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and second adjustment amplitude data corresponding to a rotational angular position of the movable base measured orthogonally by the vibration measuring instrument when the adjustment weight is changed by moving the adjustment weight circumferentially relative to the movable base or by increasing/decreasing the adjustment weight, and the movable base is rotated;

means for obtaining an approximate expression of the first influence wave data based on the influence wave data and a change in the adjustment weight; and

means for calculating first approximate influence wave data of the conditions of the adjustment weight by substituting a plurality of conditions of an arbitrary position and weight of the adjustment weight into the approximate expression.

2. The adjustment device of a rotary machine according to claim 1 , wherein

the means for obtaining first influence wave data calculates second influence wave data from a difference between third adjustment amplitude data corresponding to a rotational angular position of the movable base measured along the axis by the vibration measuring instrument axis when the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and fourth adjustment amplitude data corresponding to a rotational angular position of the movable base measured along the axis by the vibration measuring instrument when the adjustment weight is moved along the axis of the movable base, and the movable base is rotated,

the-means for obtaining the approximate expression derives an approximate expression of the second influence wave data based on the second influence wave data and a change amount resulting from the movement of the adjustment weight, and

the means for calculating calculates second approximate influence wave data from the change amount of the adjustment weight by using the approximate expression of the second influence wave data.

3. An adjustment method comprising:

measuring, in a rotary machine including a movable base formed in an annular shape and configured to rotate around an axis so as to enable an object to move inside the annular shape, an amplitude of vibration of the rotary machine along the axis and a direction orthogonal to the axis when the movable base is rotated;

calculating a position and a weight of an adjustment weight by using calculation means, based on the measured amplitude of vibration so that the amplitude of vibration of the movable base is minimized; and

adjusting the adjustment weight on the movable base based on the position and the weight of the adjustment weight calculated by the calculation means;

wherein the calculating step comprises:

obtaining first influence wave data by calculating a difference between first adjustment amplitude data corresponding to a rotational angular position of the movable base at a time the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and second adjustment amplitude data corresponding to a rotational angular position of the movable base measured orthogonally when the adjustment weight is changed by moving the adjustment weight circumferentially relative to the movable base or by increasing/decreasing the adjustment weight, and the movable base is rotated;

deriving an approximate expression of the first influence wave data based on the influence wave data and a change in the adjustment weight; and

calculating first approximate influence wave data of the conditions of the adjustment weight by substituting a plurality of conditions of an arbitrary position and weight of the adjustment weight into the approximate expression.

4. The adjustment method of a rotary machine according to claim 3 , wherein the calculating step further comprises:

obtaining second influence wave data by calculating a difference between third adjustment amplitude data corresponding to a rotational angular position of the movable base at the time the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and fourth adjustment amplitude data corresponding to a rotational angular position of the movable base at the time the adjustment weight is moved along the axis of the movable base, and the movable base is rotated,

deriving an approximate expression of the second influence wave data based on the second influence wave data and a change amount resulting from the movement of the adjustment weight, and

calculating second approximate influence wave data from the change amount of the adjustment weight by using the approximate expression of the second influence wave data.

5. A manufacturing method of a rotary machine, comprising:

assembling a rotary machine including a rotatable movable base and a stationary base for supporting the movable base;

measuring an amplitude of vibration of the rotary machine along an axis and a direction orthogonal to the axis when the movable base is rotated;

calculating a position and a weight of an adjustment weight by using calculation means based on the measured amplitude of vibration so that the amplitude of vibration of the movable base is minimized,

wherein the calculating step further comprises

obtaining first influence wave data by calculating a difference between first adjustment amplitude data corresponding to a rotational angular position of the movable base at a time the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and second adjustment amplitude data corresponding to a rotational angular position of the movable base measured orthogonally when the adjustment weight is changed by moving the adjustment weight circumferentially relative to the movable base or by increasing/decreasing the adjustment weight, and the movable base is rotated;

deriving an approximate expression of the first influence wave data based on the influence wave data and a change in the adjustment weight; and

calculating first approximate influence wave data of the conditions of the adjustment weight by substituting a plurality of conditions of an arbitrary position and weight of the adjustment weight into the approximate expression; and

attaching the adjustment weight to the movable base based on the position and the weight of the adjustment weight calculated by the calculation means.

6. The manufacturing method of a rotary machine according to claim 5 , wherein the calculating step further comprises:

obtaining second influence wave data by calculating a difference between third adjustment amplitude data corresponding to a rotational angular position of the movable base at the time the adjustment weight having an arbitrary weight is arranged at an arbitrary circumferential position of the movable base, and the movable base including the adjustment weight is rotated, and fourth adjustment amplitude data corresponding to a rotational angular position of the movable base at the time the adjustment weight is moved along the axis of the movable base, and the movable base is rotated;

deriving an approximate expression of the second influence wave data based on the second influence wave data and a change amount resulting from the movement of the adjustment weight; and

calculating second approximate influence wave data from the change amount of the adjustment weight by using the approximate expression of the second influence wave data.

7. The manufacturing method of a rotary machine according to claim 5 , wherein

the rotary machine is an X-ray CT apparatus; and

the movable base includes an X-ray tube and a detector.