JP2010281744A - Method of imbalance measurement and instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain highly accurate imbalance data unaffected by a temperature difference between a bearing and a lubricant, with the imbalance data prevented from varying for each rotary machine. <P>SOLUTION: A test run for rotating a rotaey body is performed a plurality of times (step S1). For each test run, a data acquiring step S2, a deviation calculating step S3, and a determining step S4 are performed. At the data acquiring step S2, vibration of a support and a rotation angle of the rotary body are detected, and imbalance data on the rotary body are calculated from the vibration and the rotation angle. At the calculating step S3, an amount of deviation is calculated, expressing an amount deviated from imbalance data on a test run deviate from imbalance data on a test run performed just before the test run. At the determining step S4, it is determined whether a deviation is equal to or less than a threshold. The steps S1 to S4 are repeated until the deviation becomes equal to or less than the threshold. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an unbalance measuring method and apparatus for measuring an unbalance of a rotating body provided in a rotating machine.

  In the present application, the rotating machine is a fluid machine in which rotating blades that exert force on a fluid are provided on a rotating body. The rotating machine includes a prime mover and a driven machine. The prime mover converts the energy of the fluid into rotational kinetic energy by rotationally driving the rotating body by the pressure that the fluid acts on the rotor blades. This rotational kinetic energy is the kinetic energy of the rotating body including the rotor blades. As a prime mover, for example, there is a gas turbine (axial turbine, radial turbine). The driven machine applies rotational kinetic energy to the fluid by rotating the rotor blades that are rotationally driven to apply pressure to the fluid. This rotational kinetic energy is the kinetic energy of the rotating body including the rotor blades. Examples of the driven machine include a compressor (an axial flow compressor, a mixed flow compressor, a cross flow compressor, and a pump provided in a centrifugal compressor, an aircraft engine, or the like). In addition, some rotating machines have a turbocharger that functions as both a prime mover and a driven machine.

  Test the rotating machine to measure the unbalance of the rotating body. At this time, the vibration generated by the rotational motion of the rotating body is detected and the rotation angle of the rotating body is detected. From the detected vibration and rotation angle, it is determined how much unbalance amount exists in which rotation direction position. Such unbalance measurement is described in Patent Document 1 below, for example.

JP 2008-267907 A

However, in the past, the accuracy of unbalance measurement has sometimes been reduced. The following can be considered as the reason.
(1) Lubricating oil is supplied to the bearing that rotatably supports the rotating body during the trial operation, but there is a temperature difference between the bearing and the lubricating oil supplied to the bearing at the start of the trial operation. Due to this temperature difference, an error may occur in the detected vibration.
(2) Due to the assembly tolerance of the rotating machine, the time until the operation of the rotating machine is stabilized differs for each rotating machine. For example, when the rotating machine is a supercharger, the time until the internal air is removed and the temperature of the bearing is stabilized differs for each supercharger. As a result, the imbalance data may be different for each individual rotating machine.

  Therefore, an object of the present invention is to provide an unbalance measuring method that can acquire high-precision unbalance data without being affected by the temperature difference between the bearing and the lubricating oil and without causing unbalance data to vary between individual rotating machines. Is to provide.

In order to achieve the above object, according to the present invention, an unbalance measuring method for measuring an unbalance of a rotating body,
In a state where the rotating body is rotatably supported by a support body, a test operation for rotating the rotating body is performed a plurality of times,
For each trial run, perform a data acquisition step, a deviation amount calculation step, and a determination step,
In the data acquisition step, the vibration of the support and the rotation angle of the rotating body are detected, and unbalance data of the rotating body is calculated from the vibration and the rotation angle,
In the deviation amount calculating step, the unbalance data obtained in the trial operation is calculated as a deviation amount representing an amount of deviation from the unbalance data obtained in the trial operation performed immediately before the trial operation,
In the determination step, it is determined whether the deviation amount is a threshold value or less,
The unbalance measurement method according to claim 1, wherein the trial run, the data acquisition step, the deviation amount calculation step, and the determination step are repeated until the deviation amount becomes equal to or less than the threshold value. Is done.

In the above-described unbalance measurement method of the present invention, the trial run of the rotating body is performed a plurality of times, and for each trial run, a data acquisition step, a deviation amount calculation step, and a determination step are performed. In the data acquisition step, unbalance data is calculated. In the deviation amount calculating step, a deviation amount indicating how much the unbalanced data is deviated from the unbalance data obtained in the previous test run is calculated. In the determining step, the deviation amount is a threshold. Since it is determined whether or not the value is equal to or less than the value, it can be determined whether the unbalanced data is stable, thereby obtaining highly accurate unbalanced data. Specifically:
(1) Conventionally, when there is a temperature difference between the bearing that rotatably supports the rotating body and the lubricating oil supplied to the bearing, an accurate unbalance amount cannot be measured. On the other hand, in the above-described present invention, when the deviation amount is equal to or smaller than the threshold value, it can be determined that the temperature difference is eliminated, and thus accurate unbalance data can be acquired.
(2) Conventionally, due to the assembly tolerance of the rotating machine, the time until the operation of the rotating machine is stabilized differs for each individual rotating machine, and thus unbalanced data varies for each individual rotating machine. On the other hand, in the above-described present invention, when the deviation amount is equal to or less than the threshold value, it can be determined that the operation of the rotating machine is stable, and thus unbalanced data varies for each individual rotating machine. Can be prevented.

  According to a preferred embodiment of the present invention, in the determination step, when it is determined that the deviation amount is equal to or less than the threshold value, the rotation is performed based on unbalance data calculated for the last test run. A part of the body is cut, thereby correcting the balance of the rotating body.

  As described above, when the deviation amount is equal to or less than the threshold value, the balance of the rotating body is corrected using the unbalance data of the last test run. Therefore, high-accuracy balance correction is possible, and it is possible to prevent a difference in balance correction accuracy between individual rotating machines.

Further, according to a preferred embodiment of the present invention, the imbalance data U _n is

U _n = G _n / E

Where E is an influence coefficient of the rotating body, subscript n is a number indicating the number of trial runs, and G _n is

_{G n = g n (cosψ n} + jsinψ n)

J is an imaginary unit, g _n is the amplitude of the same frequency component as the number of rotations per second of the rotating body, and ψ _n is a reference for the rotation angle. The phase difference of the frequency component relative to the value,
The deviation amount ΔU is:

ΔU _n = | U _n −U _n−1 |

It is represented by

Based on such amount of deviation .DELTA.U, imbalance data U _n it can determine whether the stable.

Moreover, in order to achieve the above-mentioned object, according to the present invention, an unbalance measuring device for measuring an unbalance of a rotating body,
A support that rotatably supports the rotating body;
An acceleration sensor for detecting the acceleration of the support;
An angle sensor for detecting a rotation angle of the rotating body;
A computing unit that calculates unbalanced data of the rotating body based on the detected acceleration and the rotation angle;
Trial operation for rotationally driving the rotating body is performed a plurality of times, the calculator calculates the unbalance data for each trial operation,
A deviation calculating unit for calculating a deviation amount of the unbalanced data between two consecutive trial runs;
An unbalance measuring device is provided, comprising: a determination unit that determines whether the deviation amount is equal to or less than a threshold value.

  In the above-described unbalance measuring device of the present invention, the computing unit calculates the unbalance data for each trial run, and the deviation calculation unit calculates the deviation amount of the unbalance data between the two consecutive trial runs. Then, since the determination unit determines whether or not the deviation amount is equal to or less than the threshold value, it can determine whether the unbalance data is stable, thereby acquiring highly accurate unbalance data. In addition, unbalanced data can be stabilized quickly by performing trial run several times continuously.

  According to the present invention described above, highly accurate unbalanced data can be acquired without being affected by the temperature difference between the bearing and the lubricating oil and without causing unbalanced data to vary among individual rotating machines.

The imbalance measuring device which can be used for the unbalance measuring method of this invention is shown. It is an II-II arrow line view of FIG. It is a waveform which shows vibration data. It is a complex plane representing vibration data. It is a complex plane representing the amount of deviation of unbalanced data. It is a flowchart which shows the imbalance measuring method by embodiment of this invention. The case where the unbalance measuring device of this invention is applied to a supercharger is shown.

  The best mode for carrying out the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure, and the overlapping description is abbreviate | omitted.

  FIG. 1 shows an unbalance measuring apparatus 10 according to an embodiment of the present invention. 2 is a view taken in the direction of arrows II-II in FIG. The unbalance measuring device 10 includes a support 3, an acceleration sensor 5, an angle sensor 7, a calculator 9, a deviation calculation unit 11, a determination unit 13, and a cutting device 15.

  The support 3 supports the rotating body 17 of the rotating machine. The rotating body 17 is rotatable about the axis C of the rotating body 17 while being supported by the support body 3. In addition, a part of the support body 3 may be comprised by the stationary side member of a rotary machine.

  The acceleration sensor 5 is attached to the support 3. The acceleration sensor 5 detects the acceleration (that is, vibration) of the support 3 while the rotating body 17 is rotating, and outputs a vibration signal indicating the acceleration to the calculator 9. A known sensor can be used as the acceleration sensor 5.

  The angle sensor 7 detects the rotation angle of the rotating body 17 and outputs a rotation angle signal indicating the rotation angle to the calculator 9. The rotation angle changes from zero degrees to 360 degrees when the rotating body 17 rotates once. That is, the rotation angle indicates an angle at which the rotator 17 is rotated from the rotation phase (start point rotation angle) of the rotator 17 serving as a predetermined start point.

The computing unit 9 generates vibration data G _n based on the detected acceleration (that is, the vibration signal) and the rotation angle (that is, the rotation angle signal), and further, the vibration data G _{n is used} to generate the vibration data G _n. calculating the imbalance data _{U n} of the rotary body 17. In the present embodiment, performed a plurality of times trial for rotating the rotating member 17 as described later, for each test run, the calculator 9 generates a vibration data G _n, calculates the unbalance data U _n.
The subscript n of U and G is a trial run number indicating the number of trial runs. Thus, for example, G _n is the vibration data for the n-th trial, U _n is an unbalanced data calculated by the n-th trial. The same applies to the subscript n attached to other symbols below.

The vibration data G _n includes a vibration amplitude g _n and a phase difference ψ _n . FIG. 3 shows the vibration amplitude g _n and the phase difference ψ _n . In FIG. 3, the horizontal axis indicates the rotation angle of the rotating body 17 detected by the angle sensor 7, and the vertical axis indicates the intensity of the primary vibration among the vibrations detected by the acceleration sensor 5. The primary vibration is a vibration having the same frequency component as the rotational speed of the rotating body 17. That is, the primary vibration amplitude gn is the vibration signal output from the acceleration sensor 5 having the same frequency [Hz] as the rotational speed (the number of rotations per second) of the rotating body 17 when vibration is detected by the acceleration sensor 5. It is the vibration extracted from. In FIG. 3, the phase difference ψ _n indicates a deviation of the primary vibration with respect to the reference value of the rotation angle (zero degree in the example of FIG. 3). That is, the phase difference ψ _n indicates a shift of the rotation angle that is the starting point of the period of the primary vibration with respect to the reference value (reference rotation angle). Such vibration data _Gn is represented by a complex number. FIG. 4 shows the vibration data _Gn expressed in complex numbers. As shown in FIG. 4, the vibration data G _n is represented by a complex number, where the amplitude g _{n of the} primary vibration is a magnitude (absolute value), the above-described phase difference ψ is a declination angle. That is, vibration data _Gn is expressed by the following equation (1), where j is an imaginary unit.

_{G n = g n (cosψ n} + jsinψ n) ··· (1)

The imbalance data _{U n,} expressed by the following equation (2).

U _n = G _n / E (2)

Here, E is an influence coefficient.

The influence coefficient is acquired in advance. The influence coefficient is a complex number acquired for a rotary machine of the same model as the rotary machine that is the target of the unbalance measurement method of the present invention (hereinafter referred to as a reference rotary machine). The influence coefficient may be acquired as follows using the above-described unbalance measuring device 10.
First, vibration data (hereinafter referred to as G _a ) of the formula (1) is acquired for the rotating body 17 of the reference rotating machine.
Then, with the reference rotational fitted with weight at a predetermined position of the rotating member 17 of the machine, by rotating the rotating member 17, the formula (1) of the vibration data (hereinafter, referred to as G _b) to obtain the.
Thereafter, the arithmetic unit 9 calculates the influence coefficient E by the following equation (3).

E = (G _b −G _a ) / M (cos φ + j sin φ) (3)

Here, M is the reduced mass of the weight. The reduced mass M is M = r ₀ × m ₀ . r ₀ is a radial distance from the axis C of the rotating body 17 to the center of gravity of the weight (that is, a radial distance with respect to the axis C), and m ₀ is a mass of the weight. On the other hand, φ indicates the rotational position of the center of gravity of the weight (that is, the position in the direction around the axis C). This rotational direction position may be expressed by a phase with respect to a predetermined rotational direction position. The weight is, for example, a screw, and the rotating body 17 may be formed with a screw hole for attaching this screw. Moreover, you may acquire an influence coefficient by cutting a part of rotary body 17 instead of using a weight.

Deviation calculation unit 11 calculates the shift amount .DELTA.U _n of the imbalance data U _n between two consecutive said commissioning. The deviation amount ΔU is expressed by the following equation (4).

_{ΔU n = | U n -U n} -1 |

= | U _n (cos θ _n + j sin θ _n )
−U _n−1 (cos θ _n−1 + j sin θ _n−1 ) |

= | (U _n cos θ _n −U _n−1 cos θ _n−1 )
+ J (U _n sin θ _n −U _n−1 sin θ _n−1 ) |

= {(U _n cos θ _n −U _n−1 cos θ _n−1 ) ²
− (U _n sin θ _n −U _n−1 sin θ _n−1 ) ² } ^1/2 (4)

The .DELTA.U _n is expressed as FIG.

Determination unit 13, the deviation amount .DELTA.U _n it is determined whether it is below the threshold T. That is, the determination unit 13 determines whether the following expression (5) is satisfied.

ΔU _n = | U _n −U _n−1 | ≦ T (5)

  The cutting device 15 includes a cutting tool 15a (for example, an end mill) that cuts the cutting target portion 17a of the rotating body 17, and three-dimensionally (for example, the X-axis direction and the Y-axis direction of FIG. 1 orthogonal to each other). , A Z-axis direction) drive mechanism 15b, and a position control unit 15c that controls the position of the cutting tool 15a by controlling the operation of the drive mechanism 15b. The position control unit 15c cuts the cutting target portion 17a according to the input unbalance data. Note that the cutting target portion 17a is, for example, a nut or a columnar member attached to the tip of the rotating shaft that constitutes the rotating body 17.

  FIG. 6 is a flowchart illustrating an unbalance measurement method according to an embodiment of the present invention. This unbalance measurement method includes an operation step S1, a data acquisition step S2, a deviation amount calculation step S3, a determination step S4, and the like.

  In the operation step S1, a test operation is performed in which the rotating body 17 is rotationally driven in a state where the rotating body 17 is rotatably supported by the support body 3. Note that one trial operation is to increase the rotational speed of the rotating body 17 from the initial speed (for example, zero) to the measurement target rotational speed. Therefore, when the operation step S1 is performed again, the rotational speed of the rotating body 17 is set to be equal to or lower than the initial rotational speed from the measurement target rotational speed, and then the rotational speed of the rotary body 17 is changed from the initial speed to the measurement target rotational speed. Raise to.

In the data acquisition step S2, the vibration of the support 3 is detected by the acceleration sensor 5 in a state where the rotating body 17 is rotating at the measurement target rotation speed in the operation step S1, and the rotation angle of the rotating body 17 is determined as an angle. It is detected by the sensor 7. Further, in the data acquisition step S2, the arithmetic unit 9, from the rotation angle and the detected vibration, and calculates the vibration data G _n described above, calculates the unbalance data U _n of the rotary body 17. The vibration data G _n is a vibration having the same frequency component as the measurement target rotation speed (the number of rotations per second) in the vibration.

In the deviation amount calculating step S3, the imbalance data G _n of the current of the commissioning, the shift amount .DELTA.U _n which represents the amount that is offset from the imbalance data G _n-1 of the trial was carried out immediately before the operation It is calculated by the deviation calculation unit 11. However, in FIG. 6, when the trial run has only been performed once from the start, steps S3 and S4 are omitted and the process proceeds to step S6.

In the determining step S4, determination unit 13, the deviation amount .DELTA.U _n calculated by the shift amount calculating step S3 to determine the whether less than the threshold value T. If the deviation amount .DELTA.U _n is less than or equal to the threshold T, the process proceeds to correction step S5, otherwise, the process proceeds to step S6.

  In step S6, the number of trial runs n is increased by 1, and the process proceeds to step S7.

In step S7, it is determined whether the number n of trial runs exceeds a predetermined limit number n _max . If it exceeds, it is determined that there is an abnormality in the rotating machine or the support body 3, and the present method is terminated. On the other hand, when not exceeding, it progresses to driving | running step S1, and performs the above-mentioned driving | running step S1, data acquisition step S2, deviation | shift amount calculation step S3, and judgment step S4 again.

On the other hand, in modification step S5, were calculated for the last said commissioning Been (i.e., calculated in the last data acquisition step S2) said the imbalance data U _n correction for unbalance data U _f, unbalance for this modification Based on the data U _f , a part of the rotating body 17 is cut. That is, the cutting device 15, based on the cutting position and cutting amount indicated unbalanced data U _f, cutting the cutting object portion 17a of the target rotating member 17. The unbalance data U _f is input from the calculator 9 to the position controller 15c. Position control unit 15c moves the cutting tool 15a by controlling the drive mechanism 15b based on _{U f,} thereby cutting the object portion 17a is cut according to _{U f.}
U _f is expressed by the following equation (6), where A is an absolute value and the declination is α.

U _f = A (cos α + jsin α) (6)

A represents an imbalance reduced mass, is A = _{r 1} × _{m 1.} Here, r ₁ is the radial distance from the axis C of the target rotating body 17 to the cutting position, and the value can be arbitrarily selected. m ₁ is a mass to be cut. On the other hand, α represents the rotational position of the cutting position. Accordingly, in the correction step S5, the cutting tool 15a is moved in the direction of the axis C until the cutting mass reaches m ₁ while being positioned at the radial position and the rotational position indicated by r ₁ and α. At this time, the position control unit 15c, and m _1, and density of the cutting target portion 17a, and the dimensions of the cutting tool 15, the cutting target portion 17a if necessary on the basis of the shape, the cutting tool 15 of the axis C The distance moved in the direction is calculated, and the drive mechanism 15b is controlled based on the distance.

  According to the unbalance measurement and apparatus of the embodiment described above, the following effects (A) and (B) can be obtained.

(A) the commissioning of a rotary machine performs a plurality of times, the each test run, perform data acquisition step S2 and the deviation amount calculating step S3 and the judgment step S4, the data acquisition step S2, calculating the imbalance data U _n, in the deviation amount calculating step S3, the imbalance data U _n calculates the shift amount .DELTA.U _n representing whether the shifted much from the imbalance data U _n-1 obtained in the previous trial, judgment step S4 so since the displacement amount .DELTA.U _n it is determined whether it is below the threshold T, can determine unbalance data U _n is stabilized, which allows obtaining a highly accurate unbalance data.
For example, conventionally, when there is a temperature difference between a bearing that rotatably supports the rotating body 17 and the lubricating oil supplied to the bearing, an accurate unbalance amount cannot be measured. In contrast, in the embodiment described above, when the shift amount .DELTA.U _n is less than or equal to the threshold T is, it can be determined that the temperature difference between the is lost, thereby, can obtain an accurate unbalance data .
Conventionally, due to the assembly tolerance of the rotating machine, the time until the operation of the rotating machine is stabilized differs for each individual rotating machine, and thus unbalanced data varies for each individual rotating machine. In contrast, in the embodiment described above, when the shift amount .DELTA.U _n is less than or equal to the threshold T is, it can be determined that the operation of the rotary machine is stabilized, thereby, each unbalance data of a rotary machine individuals It is possible to prevent scatter.

(B) When the amount of deviation .DELTA.U _n is equal to or less than the threshold value T, using the imbalance data of the last the commissioning Been to modify the balance of the rotating body 17. Therefore, high-accuracy balance correction is possible, and it is possible to prevent a difference in balance correction accuracy between individual rotating machines.

[Example]
FIG. 7 shows a case where the unbalance measuring device 10 according to the above-described embodiment is applied to a supercharger 20 as a rotating machine.

  As shown in FIG. 7, the rotating body 17 of the supercharger 20 includes a turbine blade 21 that is rotationally driven by the exhaust gas of the engine, and a compressor blade that supplies compressed air to the engine by rotating integrally with the turbine blade 21. And a rotating shaft 25 to which the turbine blade 21 is coupled at one end and the compressor blade 23 is coupled at the other end. Moreover, the supercharger 20 has the stationary side member 27 which supports the rotary body 17 rotatably. In the example of FIG. 7, the stationary member 27 is a bearing housing in which bearings 27 a and 27 b that rotatably support the rotating body 17 (rotating shaft 25) are incorporated. The supercharger 20 includes a turbine housing 29 that houses the turbine blades 21 therein, and a compressor housing (removed in FIG. 7) that houses the compressor blades 23 inside. The turbine housing 29 is formed with a flow path (scroll) through which a fluid for rotationally driving the turbine blades 21 flows. The turbine housing 29 is attached to the inside of the support 3. The support 3 is configured so that the fluid that drives the turbine blades 21 can be supplied to the flow path of the turbine housing 29 and the fluid that has driven the turbine blades 21 can be discharged to the outside of the support 3.

  Further, the support 3 supports the bearing housing 27 via the turbine housing 29 or directly. In FIG. 7, the cutting target portion 17a of the rotating body 17 is at the end portion on the compressor blade 23 side, and is a nut in this example. In FIG. 7, both the angle sensor 7 and the cutting device 15 are provided on the compressor blade 23 side. However, when the angle sensor 7 is used, the cutting tool 15 a of the cutting device 15 is retracted to a position where it does not interfere with the angle sensor 7. When the cutting device 15 is used, the angle sensor 7 is retracted to a position where it does not interfere with the cutting device 15.

  In FIG. 7, other configurations and operations of the unbalance measuring apparatus 10 may be the same as those in the above-described embodiment. Moreover, you may perform the unbalance measuring method by the above-mentioned embodiment with respect to the rotary body 17 of the supercharger 20 using the unbalance measuring device 10 shown in FIG.

  The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the scope of the present invention.

3 support body, 5 acceleration sensor, 7 angle sensor,
9 arithmetic unit, 10 unbalance measuring device, 11 deviation calculation unit,
13 Judgment part, 15 Cutting device, 17 Rotating body

Claims (4)

An unbalance measurement method for measuring the unbalance of a rotating body,
In a state where the rotating body is rotatably supported by a support body, a test operation for rotating the rotating body is performed a plurality of times,
For each trial run, perform a data acquisition step, a deviation amount calculation step, and a determination step,
In the data acquisition step, the vibration of the support and the rotation angle of the rotating body are detected, and unbalance data of the rotating body is calculated from the vibration and the rotation angle,
In the deviation amount calculating step, the unbalance data obtained in the trial operation is calculated as a deviation amount representing an amount of deviation from the unbalance data obtained in the trial operation performed immediately before the trial operation,
In the determination step, it is determined whether the deviation amount is a threshold value or less,
The unbalance measurement method according to claim 1, wherein the trial run, the data acquisition step, the deviation amount calculation step, and the determination step are repeated until the deviation amount becomes equal to or less than the threshold value.   In the determining step, when it is determined that the deviation amount is equal to or less than the threshold value, a part of the rotating body is cut based on the unbalance data calculated for the last test run, The unbalance measuring method according to claim 1, wherein the balance of the rotating body is corrected by: The imbalance data _{U n} is,

U _n = G _n / E

Where E is an influence coefficient of the rotating body, subscript n is a number indicating the number of trial runs, and G _n is

_{G n = g n (cosψ n} + jsinψ n)

J is an imaginary unit, g _n is the amplitude of the same frequency component as the number of rotations per second of the rotating body, and ψ _n is a reference for the rotation angle. The phase difference of the frequency component relative to the value,
The deviation amount ΔU is:

ΔU _n = | U _n −U _n−1 |

The unbalance measurement method according to claim 1, wherein the unbalance measurement method is represented by: An unbalance measuring device that measures the unbalance of a rotating body,
A support that rotatably supports the rotating body;
An acceleration sensor for detecting the acceleration of the support;
An angle sensor for detecting a rotation angle of the rotating body;
A computing unit that calculates unbalanced data of the rotating body based on the detected acceleration and the rotation angle;
Trial operation for rotationally driving the rotating body is performed a plurality of times, the calculator calculates the unbalance data for each trial operation,
A deviation calculating unit for calculating a deviation amount of the unbalanced data between two consecutive trial runs;
An unbalance measuring device, comprising: a determination unit configured to determine whether the deviation amount is equal to or less than a threshold value.

Images