JP5713276B2 - Bearing deterioration judgment method and device - Google Patents

Description

  In the present invention, when a rotating body of a plurality of rotating machines is sequentially supported by a bearing to acquire unbalance data of the rotating body and to correct the unbalance of the rotating body, the deterioration of the bearing used in this way The present invention relates to a bearing deterioration judging method and apparatus for judging the above.

  The rotating machine is, for example, a fluid machine in which rotating blades that exert force on a fluid are provided on a rotating body. There are a prime mover and a driven machine in the fluid 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. 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. 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 fluid machines have a turbocharger that functions as both a prime mover and a driven machine. In the present application, the rotary machine is not limited to a fluid machine.

  The influence coefficient is used to correct the unbalance of the rotating body. The influence coefficient indicates the vibration change of the rotating body with respect to the balance change of the rotating body provided in the rotating machine. The influence coefficient is acquired in advance before correcting the balance of the rotating body.

  The influence coefficient can be obtained by using a test weight as follows, for example. First, without using the trial weight, the rotating body is rotated, and the vibration of the supporting body that supports the rotating body is measured. Next, the trial weight is attached to the rotating body, the rotating body is rotated, and the vibration of the support that supports the rotating body is measured. Then, the influence coefficient is calculated from the vibration when the trial weight is not used, the vibration when the trial weight is attached, and the mass and attachment position of the trial weight. The vibration used for calculating the influence coefficient is preferably a vibration having the same frequency component as the rotation speed of the rotating body (that is, the number of rotations per second).

  Using the influence coefficient obtained in this way, the imbalance of the rotating body is measured and corrected as follows. First, vibration data is generated based on vibration generated by the rotation of the rotating body supported by the bearing. Next, based on the vibration data and the above-described influence coefficient, unbalance data of the rotating body is calculated. At the correction position indicated by the unbalance data, the rotating body is cut by the mass indicated by the unbalance data. Thereby, the balance of the rotating body is corrected. Such an imbalance correction method is called an influence coefficient method, and is described in, for example, Patent Document 1 below.

JP 2008-102049 A

  When the above-mentioned unbalance measurement is repeatedly performed on a plurality of rotating machines of the same model, the unbalance measurement cannot be performed accurately if the above-described bearing deteriorates (for example, wear). In other words, when the bearing deteriorates, the vibration when the rotating body supported by the bearing is rotated is caused not only by the unbalance of the rotating body but also by the deterioration of the bearing. Balance measurement cannot be performed accurately.

  Therefore, an object of the present invention is to prevent a decrease in imbalance measurement accuracy due to deterioration of the bearing.

In order to achieve the above-mentioned object, the rotating bodies of a plurality of rotating machines are sequentially supported by bearings to obtain unbalanced data of the rotating bodies, and the rotating bodies against the balance change of the rotating bodies supported by the bearings A bearing deterioration determination method for repeatedly performing a change tracking process for detecting a change in the influence coefficient at a time interval, and determining deterioration of the bearing based on the change, with the data indicating the vibration change of the
In each variation tracking process,
(A) Rotating a rotating body supported by the bearing, and generating vibration data based on vibration generated by the rotation,
(B) A balance change is given to the rotating body,
(C) Rotating the rotating body supported by the bearing, and generating vibration data based on vibration generated by the rotation,
(D) Based on the vibration data generated in (A) and (C) and the balance change given in (B), the influence coefficient of the rotating body is calculated,
In each variation tracking process performed after the second time, the influence coefficient calculated in (D) of the variation tracking process performed first is used as an initial influence coefficient.
(E) Find the deviation between the influence coefficient calculated in (D) of the change tracking process and the initial influence coefficient, determine whether this deviation is larger than an allowable value,
(F) Provided is a bearing deterioration determination method characterized by outputting a deterioration notification signal indicating deterioration of the bearing based on the determination.

According to a preferred embodiment of the present invention, in (E), each time it is determined that the deviation is larger than the allowable value, the count that is the number of times the determination is made is increased by one,
When the count reaches the preset number, the deterioration notification signal is output in (F).

  According to another embodiment of the present invention, when it is determined in (E) that the deviation is larger than the allowable value, the deterioration notification signal is output in (F).

  Preferably, each variation tracking process is performed using the same rotating body for obtaining the influence coefficient.

In order to achieve the above-mentioned object, according to the present invention, a rotating body supported by the bearing is obtained by sequentially supporting the rotating bodies of a plurality of rotating machines by a bearing and acquiring unbalance data of the rotating bodies. In order to determine the deterioration of the bearing based on the fluctuation tracking process for detecting the fluctuation of the influence coefficient repeatedly at time intervals using the data indicating the vibration change of the rotating body with respect to the balance change as an influence coefficient. Bearing deterioration judgment device used for
An influence coefficient fluctuation data acquisition device for acquiring the fluctuation of the influence coefficient;
A deterioration determining unit that determines deterioration of the bearing based on the fluctuation,
The influence coefficient variation data acquisition device, in each variation tracking process,
(A) generating vibration data based on vibration generated by rotating a rotating body supported by the bearing;
(B) generating vibration data on the basis of vibration generated by rotating the rotating body supported by the bearing and having a balance change;
(C) Based on the vibration data generated in (a) and (b) and the balance change given in (b), the influence coefficient of the rotating body is calculated,
With the influence coefficient calculated in (c) of the fluctuation tracking process performed first as the initial influence coefficient, the deterioration determination unit is configured to perform each fluctuation tracking process performed after the second time.
(D) Find the deviation between the influence coefficient calculated in (c) of the change tracking process and the initial influence coefficient, determine whether this deviation is larger than an allowable value,
(E) A bearing deterioration determination device is provided, which outputs a deterioration notification signal indicating deterioration of the bearing based on the determination.

According to the present invention described above, the variation tracking process is performed at time intervals in order to detect the variation of the influence coefficient, and the influence coefficient acquired in the first fluctuation tracking process is used as the initial influence coefficient, and is performed after the second time. In each variation tracking process, a deviation between the influence coefficient acquired in the process and the initial influence coefficient is obtained, it is determined whether the deviation is larger than an allowable value, and a deterioration notification indicating deterioration of the bearing based on the determination. Since a signal is output, it can be determined that the bearing has deteriorated by this deterioration notification signal.
Therefore, if it is determined that the bearing has deteriorated in this way, for example, by replacing the bearing with a new one, it is possible to prevent a decrease in unbalance measurement accuracy due to the deterioration of the bearing.

The bearing deterioration judgment apparatus which can be used for the bearing deterioration judgment method of this invention is shown. It is explanatory drawing of vibration data. It is a flowchart which shows the bearing deterioration judgment method by 1st Embodiment or 2nd Embodiment of this invention. (A) shows the influence coefficient acquisition method in 1st Embodiment, (B) shows the influence coefficient acquisition method in 2nd Embodiment. The case where a gas bearing is used as a bearing which supports a rotating body is shown.

  An embodiment 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. 1A shows an unbalance correction device 20 that corrects an unbalance of a rotating body 13 provided in a rotary machine. FIG. 1B is a BB arrow view of FIG.
The unbalance correction device 20 includes a bearing deterioration determination device 10 and a removal processing device 11.

  The bearing deterioration determination device 10 is used in a bearing deterioration determination method during imbalance correction in the first embodiment or the second embodiment described later. That is, the bearing deterioration determination device 10 rotates the rotating body 13 in a state where the rotating body 13 is supported by the bearing 3a in order to correct the unbalance of the rotating body 13 of the rotating machine for each of the plurality of rotating machines. This is used to determine the deterioration of the bearing 3a when acquiring unbalance data of the rotating body 13 based on vibration. More specifically, the bearing deterioration determination device 10 repeatedly performs a change tracking process for detecting a change in an influence coefficient used for acquiring unbalance data of the rotating body 13 at time intervals, and the bearing is based on the change. Used to determine the degradation of 3a. The rotating body 13 may be a rotating body of a gas turbine, for example, but may be a rotating body of another rotating machine (for example, a supercharger).

  The bearing deterioration determination device 10 includes an influence coefficient variation data acquisition device 10a, a deterioration determination unit 10b, and a deterioration notification device 10c.

  The influence coefficient variation data acquisition device 10a is for acquiring the influence coefficient variation. That is, the influence coefficient variation data acquisition device 10a, in each variation tracking process, (a) the rotating body 13 supported by the bearing 3a as shown in the flowchart of FIG. 4A or FIG. Generating vibration data based on vibration generated by rotating, (b) generating vibration data based on vibration generated by rotating the rotating body 13 which is given a balance change and supported by the bearing 3a, (C) The influence coefficient of the rotating body 13 is calculated based on the vibration data generated in (a) and (b) and the balance change given in (b). It should be noted that the influence coefficient calculated in (c) of the variation tracking process performed first is set as the initial influence coefficient.

  The deterioration determination unit 10b obtains a deviation between the influence coefficient calculated in (c) of the fluctuation tracking process and the initial influence coefficient for each fluctuation tracking process performed after the second time, and this deviation is an allowable value. (E) Based on the determination, a deterioration notification signal indicating deterioration of the bearing 3a is output to the deterioration notification device 10c.

  The deterioration notification device 10c executes the deterioration notification by receiving the deterioration notification signal. The degradation notification device 10c is, for example, a light emitting device that performs degradation notification by emitting degradation notification light, a sound generator that performs degradation notification by emitting degradation notification sound, or a degradation notification display. It may be a display device that performs a deterioration notification by performing.

  The influence coefficient variation data acquisition device 10 a includes a support 3, a first vibration sensor 5 a, a second vibration sensor 5 b, an angle sensor 7, and a calculation device 9.

  The support body 3 has a bearing 3a, and rotatably supports the rotating body 13 of the rotary machine via the bearing 3a. That is, the rotating body 13 is rotatable around the central axis C of the rotating body 13 while being supported by the bearing 3 a of the support body 3.

The first and second vibration sensors 5 a and 5 b are attached to the support 3. The vibration sensors 5a and 5b measure the vibration (that is, acceleration, speed, displacement, or load) of the support 3 while the rotating body 13 is rotating, and send a vibration signal indicating the vibration to the arithmetic unit 9. Output. As the vibration sensors 5a and 5b, known sensors that can be used for acquiring the influence coefficient can be used.
In FIG. 1, the first and second vibration sensors 5 a and 5 b are attached to the support 3 at different positions.

  The angle sensor 7 measures the rotation angle of the rotating body 13 and outputs a rotation angle signal indicating the rotation angle to the arithmetic device 9. The rotation angle changes from zero degrees to 360 degrees when the rotating body 13 rotates once. The angle sensor 7 may be, for example, a photoelectric rotary encoder or a magnetic rotary encoder.

The arithmetic unit 9 generates vibration data based on the vibration signal (measured vibration) and the rotation angle signal (measured rotation angle). The vibration data is composed of vibration amplitude and phase θ. FIG. 2A shows the amplitude and phase θ of the vibration. 2A, the horizontal axis indicates the rotation angle of the rotating body 13 measured by the angle sensor 7, and the vertical axis indicates the intensity of the primary vibration among the vibrations detected by the vibration sensor 5a or 5b. . The primary vibration is a vibration having the same frequency component as the rotational speed of the rotating body 13. That is, the primary vibration is a component having the same frequency [Hz] as the rotational speed (the number of rotations per second) of the rotating body 13 during vibration measurement by the vibration sensor 5a or 5b. It is the vibration extracted from the vibration signal. In FIG. 2A, the phase θ represents the deviation of the primary vibration with respect to the reference rotation angle (zero degree in the example of FIG. 2A). That is, the phase θ represents a deviation of the rotation angle that is the starting point of the period of the primary vibration with respect to the reference rotation angle.
The vibration data is represented by complex numbers. FIG. 2B shows vibration data represented by complex numbers. As shown in FIG. 2B, vibration data is represented by complex numbers with R as the magnitude (absolute value) of the amplitude of the primary vibration and the above-mentioned phase θ as a declination (the same applies hereinafter). The arithmetic device 9 generates complex vibration data from the vibration signal from the vibration sensor 5a or 5b and the rotation angle signal from the angle sensor 7 (hereinafter the same).

The removal processing device 11 includes a cutting tool 11a (for example, an end mill) for cutting the correction target portion 13a or 13b of the rotating body 13 and the cutting tool 11a in a three-dimensional manner (for example, X orthogonal to each other in FIG. 1A). A driving mechanism 11b that moves in the axial direction, the Y-axis direction, and the Z-axis direction) and a position control unit 11c that controls the position of the cutting tool 11a by controlling the operation of the driving mechanism 11b. The position control unit 11c cuts the correction target part 13a or 13b according to the input unbalance data.
The first and second correction target portions 13a and 13b are different from each other in position with respect to the direction of the central axis C of the rotating body 13.

Below, 1st Embodiment and 2nd Embodiment of the imbalance correction method (bearing deterioration judgment method) are described in order.
Preferably, the first embodiment targets the rotating body 13 having a short length in the central axis C direction, and the second embodiment targets the rotating body 13 long in the central axis C direction. In the first embodiment, one vibration sensor 5a is used, and in the second embodiment, the first and second vibration sensors 5a and 5b are used.

[First embodiment]
FIG. 3 is a flowchart showing an unbalance correction method according to the first embodiment using the above-described unbalance correction device 20. During the execution of the imbalance correction method according to the first embodiment, the bearing deterioration determination device 10 described above executes the bearing deterioration determination method (variation tracking process) according to the first embodiment.
In addition, the bearing deterioration judgment method (namely, fluctuation tracking process) by 1st Embodiment consists of step S1 and steps S8-S11 mentioned later.

In step S1, an influence coefficient α is acquired. The influence coefficient acquired in step S1 is hereinafter referred to as an initial influence coefficient.
In step S1, the rotating body 13 is installed on the support body 3 so as to rotatably support the rotating body 13 for obtaining the influence coefficient by the bearing 3a used in step S2 performed later. In this state, in step S1 ( That is, the rotating body 13 is rotated in steps S21 and S22).

The influence coefficient acquisition rotator 13 is of the same type as that of the rotator 13 used in steps S2 and S3, which will be described later, but is also used in steps S1 and S8 to be repeated thereafter. Thereby, the fluctuation factor of the influence coefficient acquired at step S1 or S8 can be reduced.
Further, the rotating body 13 for obtaining the influence coefficient is different from the rotating body 13 used in steps S2 and S3 described later.

  Step S1 includes steps S21 to S23 shown in FIG.

In step S21, while rotating the rotating body 13 supported by the bearing 3a, the angle sensor 7 measures the rotation angle while the vibration sensor 5a measures the vibration of the supporting body 3 supporting the rotating body 13.
In step S21, on the basis of the rotation angle the vibration and the angle sensor 7 the vibration sensor 5a is measured in this manner is measured, the arithmetic unit 9 generates the vibration data a _0.

In step S22, given the balance changes .DELTA.M _T to the first modified target portion 13a of the rotary member 13, the rotary member 13 given a balance change .DELTA.M _T supported by bearings 3a, rotates the rotating member 13 in this state . During this rotation, the angle sensor 7 measures the rotation angle while the vibration sensor 5 a measures the vibration of the support 3 that supports the rotator 13. In this example, by attaching a trial weight to the first correction target portion 13a of the rotating body 13, a balance change is given to the first correction target portion 13a.
In step S22, the vibration and the angle sensor 7 the vibration sensor 5a is measured in this way on the basis of the rotation angle measured, the arithmetic unit 9 generates the vibration data a _1.

In step S23, the vibration data _{a 0} generated in step S21, the vibration data _{a 1} generated in step S22, on the basis of the balance change .DELTA.M _T given in step S22, to calculate the influence coefficient α by the arithmetic unit 9 . This calculation is performed by the following equation (1).

α = (a ₁ −a ₀ ) / ΔM _T (1)

.DELTA.M _T in the above formula (1) is represented by the following equation (2).

ΔM _T = A _T (cos θ _T + j sin θ _T ) (2)

Here, j is an imaginary unit, and _AT is the mass of the trial weight attached to the first correction target portion 13a in step S22, and the position and rotation of the trial weight attached to the first correction target portion 13a. It is a product of the distance from the center axis C of the body 13 and θ _T is a phase indicating a circumferential position (position in the direction around the center axis C, the same applies hereinafter) where the trial weight is attached to the rotating body 13. Note that the origin of theta _T coincides with the origin of the detected rotational angle by the angle sensor 7.

  In step S2, the rotating body 13 of the rotating machine subject to unbalance correction is supported by the bearing 3a. That is, the rotary body 13 is installed on the support body 3 so as to be rotatably supported by the bearing 3a used in step S1. In this state, the next step S3 is performed.

  In step S3, the rotating body 13 of the rotating machine is rotated, and in this state, the angle sensor 7 measures the rotation angle while the vibration sensor 5a measures the vibration of the support body 3 that supports the rotating body 13. Thus, based on the vibration measured by the vibration sensor 5a and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates vibration data a.

In step S4, based on the initial influence coefficient acquired in step S1 and the vibration data a generated in step S3, the arithmetic unit 9 calculates the first and second unbalanced data U by the following equation (3). calculate.

U = a / α (3)

  In step S5, the arithmetic unit 9 determines whether or not the unbalance amount indicated by the unbalance data U calculated in step S4 is equal to or less than a threshold value.

If the determination in step S5 is YES, the unbalance correction of the current rotating body 13 is terminated and the process proceeds to step S7.
On the other hand, if the determination in step S5 is no, the process proceeds to step S6.

  In step S6, the first correction target portion 13a of the rotating body 13 is removed (cut) based on the removal position and the removal amount indicated by the unbalance data U calculated in step S4.

The removal process of the first correction target portion 13a in step S6 is performed as follows. The unbalance data U calculated in step S4 is input from the arithmetic device 9 to the position control unit 11c. The position controller 11 c moves the cutting tool 11 a by controlling the drive mechanism 11 b based on the unbalance data U, and thereby the correction target portion 13 a is removed according to the unbalance data U.
The unbalanced data U is expressed by the following equation (4), where A is an absolute value, the declination is θ, and j is an imaginary unit.

U = A (cos θ + jsin θ) (4)

Here, A indicates an unbalance amount, and when A is a product of x and y, x is a radial distance from the central axis C of the rotating body 13 to the removal processing position in step S6. Yes, y is the mass to be removed (cut) in step S6. On the other hand, θ represents the circumferential position of the removal processing position. Therefore, in step S6, the cutting tool 11a moves in a direction parallel to the central axis C until the removal processing mass becomes y in a state where the cutting tool 11a is positioned at the radial position and the circumferential position indicated by x and θ. At this time, the position control unit 11c calculates a distance for moving the cutting tool 11a in a direction parallel to the central axis C based on the size of the cutting tool 11a, the density of the correction target portion 13a, and the like, and based on the distance. The drive mechanism 11b is controlled.
In addition, the removal process of step S6 may be performed in a state where the rotating body 13 to be cut is supported by the support body 3, or may be performed in another place. In the former case, the position controller 11 c may position the cutting tool 11 a at the circumferential position with respect to the direction around the central axis C based on the rotation angle of the angle sensor 7. Further, in the removal processing of the first correction target portion 13a, for example, the axial end of the rotating body 13 opposite to the correction target portion 13a is gripped by an appropriate means so that the rotating body 13 does not rotate. It is good to leave.

  After performing step S6, the process returns to step S3.

  In step S7, it is determined whether or not a set time has elapsed since the influence coefficient was acquired last time. That is, it is determined whether a set time has elapsed since step S1 or S8 was performed last time. This set time may be, for example, half a day, one day, one week, or the like.

If the determination in step S7 is yes, the process proceeds to step S8.
On the other hand, if the determination in step S7 is no, the process returns to step S2. In this case, in the returned step S2, the rotary body 13 is installed on the support body 3 so that the next rotary body 13 is supported by the bearing 3a used in the previous steps S1 and S3. In this state, the next step S3 is performed. The subsequent processing is the same as described above.

In step S8, the influence coefficient β is acquired.
In step S8, the rotating body 13 is installed on the support body 3 so as to support the rotating body 13 for obtaining the influence coefficient by the bearing 3a used in the previous steps S1 and S3, and step S8 is performed in this state.
Step S8 has steps S21 to S23 described above. That is, in step S8, the same process as step S1 is performed.

  In step S9, the deterioration determining unit 10b obtains a deviation D between the initial influence coefficient α acquired in step S1 and the influence coefficient β acquired in step S8, and determines whether the deviation D is larger than an allowable value.

Specifically, it is as follows.
The deviation D is calculated by the following equation (5). In formula (5), || means an absolute value.

D = | β−α | (5)

  In addition, after the previous step S1, the number of times that the deterioration determination unit 10b determines YES in step S9 is counted. That is, in step S9, every time the deterioration determination unit 10b determines that the deviation is larger than the allowable value, the deterioration determination unit 10b increases the count number that is the number of times the determination is made. This count is reset to 0 each time the process returns to step S1.

If the determination in step S9 is yes, the process proceeds to step S10.
On the other hand, if the determination in step S9 is no, the process proceeds to step S12.

  In step S10, the deterioration determining unit 10b determines whether or not the above-described count number has reached a preset number of times (an integer of 2 or more). Thereby, a highly reliable deterioration notification signal can be output in step S11 described later.

If the determination in step S10 is yes, the process proceeds to step S11.
On the other hand, if the determination in step S10 is no, the process proceeds to step S12.

  In step S11, the deterioration determination unit 10b outputs a deterioration notification signal to the deterioration notification device 10c, and thereby the deterioration notification device 10c executes the deterioration notification. Based on this deterioration notification, the operator replaces the bearing 3a used in step S2 with a new bearing 3a. That is, the bearing 3a attached to the support 3 is replaced with a new bearing 3a. In step S11, both the support 3 and the bearing 3a may be replaced with a new support 3 and the bearing 3a.

Accordingly, steps S1, S2, S3, and S8 are performed thereafter using the support 3 to which the new bearing 3a is attached.
If step S11 is performed, it will return to step S1 next.

  In step S12, the bearing 3a used in the previous steps S1, S2, S3 and S8 is used in the subsequent steps S2, S3 and S8 without replacing the bearing 3a attached to the support 3. I will decide. After step S12, the process returns to step S2. In this case, in the returned step S2, the rotary body 13 is supported on the support body 3 so as to rotatably support the rotary body 13 of the next rotating machine by the bearing 3a used in the previous steps S1, S2, S3 and S8. Install. In this state, the next step S3 is performed. The next rotating body 13 installed in the current step S2 is the same model as the rotating machine of the rotating body 13 installed in the previous step S2, but is provided in another rotating machine. The subsequent processing is the same as described above.

[Second Embodiment]
FIG. 3 is also a flowchart showing an unbalance correction method according to the second embodiment using the above-described unbalance correction device 20. During the execution of the imbalance correction method according to the second embodiment, the bearing deterioration determination method (variation tracking process) according to the second embodiment is executed by the bearing deterioration determination device 10 described above.
In addition, the bearing deterioration judgment method (namely, fluctuation tracking process) by 2nd Embodiment consists of step S1 and steps S8-S11 mentioned later.

In step S1, an influence coefficient is acquired. The influence coefficient acquired in step S1 is hereinafter referred to as an initial influence coefficient.
In step S1, the rotating body 13 is installed on the support body 3 so as to rotatably support the rotating body 13 for obtaining the influence coefficient by the bearing 3a used in step S2 to be performed later. In this state, the rotating body 13 is rotated in step S1 (that is, steps S31 to S33).

The influence coefficient acquisition rotator 13 is of the same type as that of the rotator 13 used in steps S2 and S3, which will be described later, but is also used in steps S1 and S8 to be repeated thereafter.
Further, the rotating body 13 for obtaining the influence coefficient is different from the rotating body 13 used in steps S2 and S3 described later.

  Step S1 includes steps S31 to S34 shown in FIG.

In step S31, when the rotating body 13 supported by the bearing 3a is rotating, the first and second vibration sensors 5a and 5b measure the vibration of the supporting body 3 that supports the rotating body 13, while the angle sensor 7 measures the rotation angle.
In step S31, the arithmetic unit 9 generates the first vibration data a _p0 based on the vibration measured by the first vibration sensor 5a and the rotation angle measured by the angle sensor 7 as described above. Thus, based on the vibration measured by the second vibration sensor 5b and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates the second vibration data _aq0 .

In step S32, a balance change ΔM _Tb is given to the first correction target portion 13a of the rotator 13, and the rotator 13 supported by the bearing 3a is rotated by being given this balance change ΔM _Tb . During this rotation, the angle sensor 7 measures the rotation angle while the first and second vibration sensors 5 a and 5 b measure the vibration of the support 3 that supports the rotating body 13. In this example, a trial weight is attached only to the first correction target portion 13a in the rotating body 13, thereby giving a balance change ΔM _Tb to the first correction target portion 13a.
In step S32, the arithmetic unit 9 generates the first vibration data _apb based on the vibration measured by the first vibration sensor 5a and the rotation angle measured by the angle sensor 7 in this manner. Thus, based on the vibration measured by the second vibration sensor 5 b and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates the second vibration data a _qb .

In step S33, a balance change ΔM _Td is given to the second correction target portion 13b of the rotator 13, and the rotator 13 supported by the bearing 3a is rotated by being given this balance change ΔM _Td . During this rotation, the angle sensor 7 measures the rotation angle while the first and second vibration sensors 5 a and 5 b measure the vibration of the support 3 that supports the rotating body 13. In this example, a trial weight is attached only to the second correction target portion 13b of the rotating body 13, thereby giving a balance change ΔM _Td to the second correction target portion 13b.
In step S33, the arithmetic unit 9 generates the first vibration data a _pd on the basis of the vibration measured by the first vibration sensor 5a and the rotation angle measured by the angle sensor 7 as described above. Thus, based on the vibration measured by the second vibration sensor 5b and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates the second vibration data a _qd .

In step S34, the first and second vibration data a _p0 and a _q0 generated in step S31, the first and second vibration data a _pb and a _qb generated in step S32, and the first vibration data generated in step S33. Based on the first and second vibration data a _pd , a _qd , the balance change ΔM _Tb given in step S32, and the balance change ΔM _Td given in step S33, the influence coefficients α _{1, b} , α _{1, d} , Α _{2, b} , α _{2, d} are calculated. This calculation is performed by the following equation (6) of [Equation 1].

ΔM _Tb in Equation (6) of [Equation 1] is expressed by the following Equation (7).

ΔM _Tb = A _Tb (cos θ _Tb + j sin θ _Tb ) (7)

Here, j is an imaginary unit, and _ATb is the mass of the trial weight attached to the first correction target portion 13a in step S32 and the position and rotation of the trial weight attached to the first correction target portion 13a. The product of the distance from the center axis C of the body 13 and θ _Tb is a phase indicating the circumferential position of the rotating body 13 where the trial weight is attached. The origin of θ _Tb coincides with the origin of the rotation angle detected by the angle sensor 7.
Similarly, ΔM _Td in equation (6) of [Equation 1] is expressed by the following equation (8).

ΔM _Td = A _Td (cos θ _Td + j sin θ _Td ) (8)

Here, j is an imaginary unit, and _ATd is the mass of the trial weight attached to the second correction target portion 13b in step S33, and the position and rotation of the trial weight attached to the second correction target portion 13b. It is a product of the distance from the center axis C of the body 13, and θ _Td is a phase indicating a circumferential position where the trial weight is attached to the rotating body 13. The origin of θ _Td coincides with the origin of the rotation angle detected by the angle sensor 7.

  In step S2, the rotating body 13 of the rotating machine subject to unbalance correction is supported by the bearing 3a. That is, the rotary body 13 is installed on the support body 3 so as to be rotatably supported by the bearing 3a used in step S1. In this state, the next step S3 is performed.

In step S3, the rotating body 13 of the rotating machine is rotated. In this state, the first and second vibration sensors 5a and 5b measure the vibration of the support body 3 that supports the rotating body 13, while the angle sensor 7 is rotating. Measures the rotation angle. Based on the vibration measured by the first vibration sensor 5a and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates the _first vibration data _{ap, 1} and thus the second Based on the vibration measured by the vibration sensor 5b and the rotation angle measured by the angle sensor 7, the arithmetic unit 9 generates second vibration data _{aq, 1} .

In step S4, the initial influence coefficients α _{1, b} , α _{1, d} , α _{2, b} , α _{2, d} acquired in step S1 and the first and second vibration data a _{p, 1} generated in step S3 are displayed. , A _{q, 1} , the arithmetic unit 9 calculates the unbalanced data U _b , U _d by the following equation (9) of [Equation 2].

  In Equation (9) of [Equation 2], −1 indicates an inverse matrix.

In step S5, the arithmetic unit 9 has an unbalance amount of the first unbalance data U _b calculated in step S4 and the second unbalance data U _d calculated in step S4 equal to or less than a threshold value. Determine whether.

For example, the sum or average value of the unbalance amount indicated by the first unbalance data U _b calculated in step S4 and the unbalance amount indicated by the second unbalance data U _d calculated in step S4 is a threshold value. Determine whether:
Alternatively, the larger value of the unbalance amount indicated by the first unbalance data U _b calculated in step S4 and the unbalance amount indicated by the second unbalance data U _d calculated in step S4 is the threshold value. Determine if it is less than or equal to the value.
Alternatively, the unbalance amount indicated by the first unbalance data U _b calculated in step S4 is equal to or less than the first unbalance data threshold value, and the second unbalance data calculated in step S4. It is determined whether the unbalance amount indicated by U _d is equal to or less than the threshold value for the second unbalance data. In this case, preferably, the threshold value for the first unbalanced data is different from the threshold value for the second unbalanced data.

If the determination in step S5 is YES, the unbalance correction of the current rotating body 13 is terminated and the process proceeds to step S7.
On the other hand, if the determination in step S5 is no, the process proceeds to step S6.

In step S6, the first correction target portion 13a of the rotating body 13 is removed (cut) based on the removal processing position and the removal processing amount indicated by the first unbalance data U _b calculated in step S4. Note that the removal processing position here is on the outer peripheral portion 13a of the tip end portion in the axial direction of the rotating body 13, and is on the alternate long and short dash line L1 in FIG. In FIG. 1B, a circle drawn with a broken line overlapping on the alternate long and short dash line L1 indicates the cutting tool 11a positioned on the alternate long and short dash line L1.
Further, in step S6, on the basis of the removal machining position and removal machining amount indicated by the second unbalance data U _d calculated in step S4, the removal processing of the second correction target portion 13b of the rotary member 13 (cutting) . In addition, the removal process position here exists on the outer peripheral part 13b of the said disk shaped member provided in the rotary body 13, and exists on the dashed-dotted line L2 in FIG. 1 (B). In FIG. 1B, a circle drawn with a broken line overlapping on the alternate long and short dash line L2 indicates the cutting tool 11a positioned on the alternate long and short dash line L2.

  The removal process of the first correction target portion 13a in step S6 is performed in the same manner as in step S6 of the first embodiment. The removal process of the second correction target portion 13b in step S6 is performed in the same manner as in step S6 of the first embodiment.

  After performing step S6, the process returns to step S3.

  In step S7, it is determined whether or not a set time has elapsed since the influence coefficient was acquired last time. That is, it is determined whether a set time has elapsed since step S1 or S8 was performed last time. This set time may be, for example, half a day, one day, one week, or the like.

If the determination in step S7 is yes, the process proceeds to step S8.
On the other hand, if the determination in step S7 is no, the process returns to step S2. In this case, in the returned step S2, the rotary body 13 is installed on the support body 3 so that the next rotary body 13 is supported by the bearing 3a used in the previous steps S1 and S3. In this state, the next step S3 is performed. The subsequent processing is the same as described above.

In step S8, an influence coefficient is acquired.
In step S8, the rotating body 13 is installed on the support 3 so as to rotatably support the rotating body 13 for obtaining the influence coefficient by the bearing 3a used in the previous steps S1 and S3. Step S8 is performed.
Step S8 includes steps S31 to S34 described above. That is, in step S8, by performing the same processing as in step S1, the influence coefficients β _{1, b} , β _{1, d} , β _{2, b} , β _{2, d} are calculated by the following equation (11) of [Equation 3]. calculate.

In step S9, the deterioration determining unit 10b uses the initial influence coefficients α _{1, b} , α _{1, d} , α _{2, b} , α _{2, d} acquired in step S1 and the influence coefficients β _{1, b} , acquired in step S8. A deviation between β _{1, d} , β _{2, b} , β _{2, d} and the initial influence coefficient is obtained, and it is determined whether or not the deviation is larger than an allowable value.

Specifically, it is as follows.
D1 _{, b} , D1 _{, d} , D2 _{, b} , D2 _{, d} are calculated by the following formulas (12) to (15). In each of the formulas (12) to (15), || means an absolute value.

D1 _{, b} = | β1 _{, b−} α1 _{, b} | (12)

D1 _{, d} = | β1 _{, d−} α1 _{, d} | (13)

D2 _{, b} = | β2 _{, b−} α2 _{, b} | (14)

D2 _{, d} = | β2 _{, d−} α2 _{, d} | (15)

Then, the determination in step S9 is performed according to any of the following (C1) to (C3).
(C1) It is determined whether or not the largest value among D _{1, b} , D _{1, d} , D _{2, b} , D _{2, d} is larger than the allowable value.
(C2) It is determined whether the sum or average value of D1 _{, b} , D1 _{, d} , D2 _{, b} , D2 _{, d} is larger than the allowable value.
(C3) D1 _{, b} is larger than the allowable value for D1 _{, b} , D1 _{, d} is larger than the allowable value for D1 _{, d} , and D2 _{, b} is for D2 _{, b} . It is determined whether or not D2 _{, d} is larger than the allowable value and D2 _{, d} is larger than the allowable value for D2 _{, d} .

  In addition, after the previous step S1, the number of times that the deterioration determination unit 10b determines YES in step S9 is counted. That is, in step S9, every time the deterioration determination unit 10b determines that the deviation is larger than the allowable value, the deterioration determination unit 10b increases the count number that is the number of times the determination is made. This count is reset to 0 each time the process returns to step S1.

If the determination in step S9 is yes, the process proceeds to step S10.
On the other hand, if the determination in step S9 is no, the process proceeds to step S12.

  In step S10, the deterioration determining unit 10b determines whether or not the above-described count number has reached a preset number of times (an integer of 2 or more).

If the determination in step S10 is yes, the process proceeds to step S11.
On the other hand, if the determination in step S10 is no, the process proceeds to step S12.

  In step S11, the deterioration determination unit 10b outputs a deterioration notification signal to the deterioration notification device 10c, and thereby the deterioration notification device 10c executes the deterioration notification. Based on this deterioration notification, the operator replaces the bearing 3a used in step S2 with a new bearing 3a. That is, the bearing 3a attached to the support 3 is replaced with a new bearing 3a. In step S11, both the support 3 and the bearing 3a may be replaced with a new support 3 and the bearing 3a.

Accordingly, steps S1, S2, S3, and S8 are performed thereafter using the support 3 to which the new bearing 3a is attached.
If step S11 is performed, it will return to step S1 next.

  In step S12, the bearing 3a used in the previous steps S1, S2, S3 and S8 is used in the subsequent steps S2, S3 and S8 without replacing the bearing 3a attached to the support 3. I will decide. After step S12, the process returns to step S2. In this case, in the returned step S2, the rotary body 13 is installed on the support body 3 so as to rotatably support the rotary body 13 of the next rotating machine with the bearing 3a used in the previous steps S1, S2 and S3. To do. In this state, the next step S3 is performed. The next rotating body 13 installed in the current step S2 is the same model as the rotating machine of the rotating body 13 installed in the previous step S2, but is provided in another rotating machine. The subsequent processing is the same as described above.

  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. For example, the following modifications 1 to 9 may be arbitrarily combined and employed, or any of modifications 1 to 9 may be employed. In this case, other points may be the same as described above, or may be changed as appropriate.

(Modification 1)
In the first embodiment or the second embodiment described above, step S10 may be omitted. In this case, if the determination in step S9 is yes, the process proceeds to step S11.

(Modification 2)
In the second embodiment described above, the two vibration sensors 5 a and 5 b are attached to the support 3. Instead, one vibration sensor may be attached to the support 3. In this case, step S1 or step S8 is performed as follows.

In step S31, the rotating body 13 of the rotating machine is rotated at the first rotation speed. In this state, the vibration sensor measures the vibration of the support body 3 that supports the rotating body 13, while the angle sensor 7 rotates the rotation angle. Measure. Based on the vibration and the rotation angle measured in this way, the arithmetic unit 9 generates first vibration data _ap0 .
In step S31, the rotating body 13 of the rotating machine is rotated at a second rotation speed different from the first rotation speed, and in this state, the vibration sensor measures the vibration of the support body 3 that supports the rotating body 13. Meanwhile, the angle sensor 7 measures the rotation angle. Based on the vibration and rotation angle measured in this way, the arithmetic unit 9 generates second vibration data a _q0 .

In step S32, a balance change is applied to the first correction target portion 13a of the rotator 13, and the rotator 13 supported by the bearing 3a is rotated at the first rotation speed. During this rotation, the angle sensor 7 measures the rotation angle while the vibration sensor measures the vibration of the support 3 that supports the rotating body 13. Based on the vibration and the rotation angle measured in this way, the arithmetic unit 9 generates first vibration data _apb .
In step S32, the same balance change as that when the first vibration data _apb is generated is given, and the rotating body 13 supported by the bearing 3a is rotated at the second rotational speed. During this rotation, the angle sensor 7 measures the rotation angle while the vibration sensor measures the vibration of the support 3 that supports the rotating body 13. Based on the vibration and rotation angle measured in this way, the arithmetic unit 9 generates second vibration data a _qb .

In step S33, a balance change is applied to the second correction target portion 13b of the rotator 13, and the rotator 13 supported by the bearing 3a is rotated at the first rotation speed. During this rotation, the angle sensor 7 measures the rotation angle while the vibration sensor measures the vibration of the support 3 that supports the rotating body 13. Based on the vibration and the rotation angle thus measured, the arithmetic unit 9 generates first vibration data a _pd .
In step S33, the same balance change as that when the first vibration data a _pd is generated is given, and the rotating body 13 supported by the bearing 3a is rotated at the second rotation speed. During this rotation, the angle sensor 7 measures the rotation angle while the vibration sensor measures the vibration of the support 3 that supports the rotating body 13. Based on the vibration and the rotation angle thus measured, the arithmetic unit 9 generates second vibration data a _qd .

The vibration data a _p0 , a _q0 , a _pb , a _qb , a _pd , and a _qd generated in this way are respectively represented by a _p0 , a _q0 , a _pb , a in the above [ _Equation 1] or [ _Equation 3]. _qb , a _pd , a _qd .

(Modification 3)
In the above description, the removal processing of the correction target portions 13a and 13b is performed in the axial direction, but may be performed in the radial direction.

(Modification 4)
In the above description, the initial influence coefficient is obtained by changing the balance of the rotating body 13 using the trial weight. However, the initial influence coefficient is obtained by removing the rotating body 13 and changing the balance of the rotating body 13. You may get it.

(Modification 5)
In the above-described embodiment, the removal processing device 11 removes the correction target portions 13a and 13b by cutting the correction target portions 13a and 13b. Instead, the removal processing device 11 uses the correction target portions 13a and 13b. Alternatively, a laser processing apparatus that irradiates a laser beam to melt and remove the correction target portions 13a and 13b may be used. In this case, in the removal processing in step S6, the removal processing mass is obtained by irradiating the laser beam to the radial position and the circumferential position (removal processing position) on the correction target portions 13a and 13b indicated by x and θ of the unbalance data U. Laser processing is performed until y becomes y described above. It should be noted that the relationship between the removal processing mass and the laser processing conditions (for example, laser beam irradiation time and energy density) is obtained in advance by experiments, and laser processing is preferably performed based on this relationship.

(Modification 6)
In the above-described embodiment, the removal processing device 11 removes the correction target portions 13a and 13b by cutting the correction target portions 13a and 13b, but instead, the removal processing device 11 performs electric discharge machining, It may be an electric discharge machine that removes the correction target portions 13a and 13b by melting the portions 13a and 13b and blowing off the melted portions. In this case, in the removal processing in step S6, the rotating body 13 is removed from the support 3 and the rotating body 13 is installed in an electric discharge machine provided at a location different from the support 3, and the electrode of the electric discharge machine is unloaded. In a state where the balance data U is positioned at the radial position and the circumferential position (removal machining position) indicated by x and θ, the electric discharge machining is performed until the removal machining mass reaches y described above. It should be noted that the relationship between the removal processing mass and the electrical discharge machining conditions (for example, the discharge time and the electrical discharge voltage) is obtained in advance by experiments, and electrical discharge machining is performed based on this relationship.

(Modification 7)
In step S7 described above, instead of determining whether or not the set time has elapsed since the last time the influence coefficient was acquired, the number of rotating bodies 13 that have executed unbalance processing since the previous step S1 or S8 is the set number. It may be determined whether or not That is, it may be determined whether the number of times that step S2 has been performed since step S1 or S8 has been performed has reached the set number.

(Modification 8)
A gas bearing may be used instead of the bearing 3a to which the lubricating oil is supplied. As shown in FIG. 5, the gas bearing 15 is incorporated in the support 3 and includes a radial bearing surface 17, a thrust bearing surface 19, air supply holes 21 and 23, and an exhaust hole 25. The air supply hole 21 opens in the radial bearing surface 17, and the air supply hole 23 opens in the thrust bearing surface 19. Pressurized gas is supplied from a gas supply source (not shown) through the air supply hole 21 between the radial bearing surface 17 and the radial journal 27 of the rotating body 13. A pressurized gas is supplied from a gas supply source (not shown) through the air supply hole 23 between the thrust bearing surface 19 and the thrust journal 29 of the rotating body 13. The pressurized gas supplied between the radial bearing surface 17 and the radial journal 27 supports the radial journal 27 of the rotating body 13 and the pressurized gas supplied between the thrust bearing surface 19 and the thrust journal 29. The thrust journal 29 of the rotating body 13 is supported. Thus, the rotating body 13 is rotatably supported by the gas bearing 15. The pressurized gas supplied between the radial bearing surface 17 and the radial journal 27 is discharged from the exhaust hole 25 to the outside of the support 3.

  When the gas bearing 15 is used, after performing step S3, the rotating body 13 is removed from the support 3, and the rotating body 13 is installed at a place different from the support 3, and the removal process of step S6 is performed.

In step S <b> 11, the deteriorated gas bearing 15 is replaced with a new gas bearing 15 by replacing the support 3 itself with a new support 3.
The deterioration of the gas bearing 15 means that the radial bearing surface 17 and the thrust bearing surface 19 are rubbed with the rotating body 13 and are damaged or worn.

(Modification 9)
In the rotating body 13, when a plurality of rotating blades (for example, turbine blades) are provided at intervals in the circumferential direction, the origin of the rotation angle detected by the angle sensor 7 is determined by the photoelectric sensor and the proximity sensor. To detect.
With respect to the photoelectric sensor, in this case, the rotating body 13 is provided with a light reflecting portion at a circumferential position around the rotation axis C where one rotor blade is located. The light reflecting portion that reflects light is, for example, marking by painting. A photoelectric sensor is provided at an installation position in the circumferential direction on the stationary side. When the light reflecting portion comes to the installation position by the rotation of the rotating body 13, the photoelectric sensor detects the light reflecting portion and outputs a detection signal.
The proximity sensor is provided at a position where the rotating blades can be detected when the rotating blades come to the installation position by the rotation of the rotating body 13. Therefore, when each rotor blade reaches the installation position by rotation, the proximity sensor also outputs a detection signal.
When detection signals are output from both the photoelectric sensor and the proximity sensor, the rotation angle detected by the angle sensor 7 is set to zero (origin). Thereby, the rotation angle detection accuracy of the angle sensor 7 is improved. For example, it is possible to prevent a decrease in rotation angle detection accuracy due to color unevenness, positional deviation, peeling, and the like of the coating.

DESCRIPTION OF SYMBOLS 3 Support body, 3a Bearing, 5a, 5b Vibration sensor, 7 Angle sensor, 9 Arithmetic apparatus, 10 Bearing deterioration judgment apparatus, 10a Influence coefficient fluctuation data acquisition apparatus, 10b Degradation judgment part, 10c Deterioration notification apparatus, 11 Removal processing apparatus, 13 Rotating body, 15 Gas bearing, 20 Unbalance correction device

Claims (5)

In obtaining the unbalance data of the rotating body by sequentially supporting the rotating bodies of a plurality of rotating machines by bearings, the data indicating the vibration change of the rotating bodies with respect to the balance change of the rotating bodies supported by the bearings is affected. As a coefficient, it is a bearing deterioration determination method that repeatedly performs a change tracking process for detecting a change in an influence coefficient at time intervals, and determines deterioration of the bearing based on the change,
In each variation tracking process,
(A) Rotating a rotating body supported by the bearing, and generating vibration data based on vibration generated by the rotation,
(B) A balance change is given to the rotating body,
(C) After (B), rotate the rotating body supported by the bearing, and generate vibration data based on vibration generated by the rotation,
(D) Based on the vibration data generated in (A) and (C) and the balance change given in (B), the influence coefficient of the rotating body is calculated,
In each variation tracking process performed after the second time, the influence coefficient calculated in (D) of the variation tracking process performed first is used as an initial influence coefficient.
(E) Find the deviation between the influence coefficient calculated in (D) of the change tracking process and the initial influence coefficient, determine whether this deviation is larger than an allowable value,
(F) A bearing deterioration determination method characterized by outputting a deterioration notification signal indicating deterioration of the bearing based on the determination. In (E), each time it is determined that the deviation is larger than the allowable value, the count that is the number of times the determination is made is increased by one,
2. The bearing deterioration determination method according to claim 1, wherein when the count reaches a preset number of times, the deterioration notification signal is output in (F). 3.   2. The bearing deterioration determination method according to claim 1, wherein if it is determined in (E) that the deviation is larger than the allowable value, the deterioration notification signal is output in (F). 3.   4. The bearing deterioration determination method according to claim 1, wherein the variation tracking process is performed by using the same rotating body for acquiring an influence coefficient. In obtaining the unbalance data of the rotating body by sequentially supporting the rotating bodies of a plurality of rotating machines by bearings, the data indicating the vibration change of the rotating bodies with respect to the balance change of the rotating bodies supported by the bearings is affected. As a coefficient, it is a bearing deterioration determination device used to repeatedly perform a change tracking process for detecting a change in an influence coefficient at time intervals, and to determine deterioration of the bearing based on the change,
An influence coefficient fluctuation data acquisition device for acquiring the fluctuation of the influence coefficient;
A deterioration determining unit that determines deterioration of the bearing based on the fluctuation,
The influence coefficient variation data acquisition device, in each variation tracking process,
(A) generating vibration data based on vibration generated by rotating a rotating body supported by the bearing;
(B) generating vibration data based on vibration generated by rotating the rotating body provided with a balance change while being supported by the bearing;
(C) Based on the vibration data generated in (a) and (b) and the balance change given in (b), the influence coefficient of the rotating body is calculated,
With the influence coefficient calculated in (c) of the fluctuation tracking process performed first as the initial influence coefficient, the deterioration determination unit is configured to perform each fluctuation tracking process performed after the second time.
(D) Find the deviation between the influence coefficient calculated in (c) of the change tracking process and the initial influence coefficient, determine whether this deviation is larger than an allowable value,
(E) A bearing deterioration determination device that outputs a deterioration notification signal indicating deterioration of the bearing based on the determination.