JP2012021864A - Balance adjusting method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the accuracy of balance adjustment of a rotary body provided in a rotational machine by cutting an area to be cut in the rotary body with the inclination of the area to be cut taken into consideration.SOLUTION: A balance adjusting method comprises: a cutting data acquiring step S1 of figuring out in advance the phase angle of cutting the area to be cut in the axial direction to eliminate imbalance and the depth of cutting respectively as a cutting phase angle and a cutting depth; an inclination measuring step S2 of measuring the inclination with respect to the axial direction of the machining start plane of the area to be cut; a shifting distance acquiring step S3 of figuring out the distance of shifting a machining tool in the axial direction from the initial position for machining at the cutting phase angle on the basis of the cutting phase angle, the cutting depth and the inclination; and a cutting step S4 of cutting the area to be cut by shifting the machining tool at the cutting phase angle from the initial position for machining in the axial direction on a side of the machining start plane by the distance of shifting.

Description

  The present invention relates to a balance correction method and apparatus for correcting the balance of a rotating body provided in a rotary 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. 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 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, the phase angle around the rotation axis where the unbalance exists is obtained, and the unbalance amount is obtained. Such unbalance measurement is described in Patent Documents 1 and 2 below, for example.

As shown in FIG. 1A, the cutting phase angle in the rotating body (for example, the phase angle where imbalance exists) is changed from the machining start surface 7 (end surface) of the cutting target portion 5a of the rotating body 5 to the unbalance amount. The cutting target portion 5a is cut in the direction of the axis C of the radial bearing 4 by the corresponding cutting depth. That is, as shown in FIG. 1B, the cutting target portion 5a is cut by the cutting depth by moving the end mill 13a from the processing initial position Pr by the distance Ld of the following equation (1).

Ld = L0 + D (1)

Here, as shown in FIG. 1B, L0 is the distance from the processing initial position Pr to the processing start surface 7, and D is the cutting depth.

JP 2008-267907 A JP 2010-048588 A

  However, when the balance is corrected, the processing start surface 7 is inclined, so that the accuracy of the balance correction may be reduced. Causes of the inclination of the processing start surface 7 include bending of the shaft 5b of the rotating body 5, processing errors of the processing start surface 7, and the like.

  When the machining start surface 7 is inclined with respect to the direction of the axis C as shown in FIG. 1C, the distance from the machining initial position Pr to the machining start surface 7 varies from L0 to Lx. Therefore, the depth at which the cutting target portion 5a is actually cut also varies. That is, even if the end mill 13a is moved from the initial working position Pr by the distance Ld described above, the cutting target portion 5a cannot be cut by the cutting depth D. Accordingly, the accuracy of balance correction is reduced.

  Therefore, an object of the present invention is to improve the accuracy of balance correction by cutting the cutting target portion in consideration of the inclination of the cutting target portion (processing start surface).

In order to achieve the above-described object, according to the present invention, an unbalanced rotating body can be obtained by partially cutting the cutting target portion of the rotating body in the axial direction of the radial bearing while the rotating body is supported by the radial bearing. A balance correction method for reducing
The position on the rotating body in the direction around the axis of the rotating body is a phase angle, the phase angle at which the cutting target portion is cut in the axial direction in order to remove the unbalance existing in the rotating body, and the depth of the cutting, respectively Cutting data acquisition step to obtain in advance as cutting phase angle and cutting depth;
An inclination measuring step for measuring an inclination of a machining start surface of the cutting target portion with respect to the axial direction;
Based on the cutting phase angle, the cutting depth and the inclination, a moving distance obtaining step for obtaining a moving distance for moving the processing tool in the axial direction from the initial processing position at the cutting phase angle;
A cutting step of cutting a cutting target portion by moving a processing tool in the axial direction on the processing start surface side from the initial position for processing by the moving distance at the cutting phase angle. A balance correction method is provided.

According to a preferred embodiment of the present invention, in the inclination measuring step,
(A) Measure the rotation angle of the rotating body,
(B) An axial distance from an initial position for measurement to a measurement position on the machining start surface is measured in the axial direction using a distance measuring device,
(C) By rotating the rotating body, the relative position between the reference point on the rotating body and the distance measuring device is changed in the direction around the axis of the rotating body,
By repeating the steps (A), (B), and (C), the relationship between the plurality of rotation angles and the plurality of axial distances is acquired, and the inclination of the machining start surface is obtained based on the relationship. .

According to another embodiment of the present invention, in the tilt measurement step,
(A) Measure the initial position for measurement of the distance measuring device in the direction around the axis of the rotating body,
(B) The axial distance from the initial position for measurement to the position to be measured on the machining start surface is measured in the axial direction using the distance measuring device,
(C) changing the initial position for measurement of the distance measuring device in the direction around the axis of the rotating body,
By repeating (A), (B), and (C), the relationship between the plurality of initial positions for measurement in the direction around the axis of the rotating body and the plurality of axial distances is acquired, and based on this relationship Thus, the inclination of the processing start surface is obtained.

In (A) above,
In a state where one end portion in the axial direction of the rotating body is gripped by a gripping device, a fitting member is fitted to the other end portion in the axial direction of the rotating body, so that the other end portion has a radius with respect to the axial direction. The fitting member is pressed toward the one end from the other end,
In this state, the axial distance from the initial position for measurement to the measured position on the processing start surface is measured in the axial direction using the distance measuring device.

In order to achieve the above object, according to the present invention, the cutting target portion of the rotating body is partially cut in the axial direction of the radial bearing while the rotating body is supported by the radial bearing. A balance correction device that reduces unbalance,
The position on the rotating body in the direction around the axis of the rotating body is a phase angle, the phase angle at which the cutting target portion is cut in the axial direction in order to remove the unbalance existing in the rotating body, and the depth of the cutting, respectively , Cutting phase angle and cutting depth,
An inclination measuring device for measuring the inclination of the machining start surface of the cutting target portion with respect to the axial direction;
Based on the measured inclination, cutting phase angle, and cutting depth, a driving amount determination device that obtains a moving distance for moving the processing tool in the axial direction from the initial processing position at the cutting phase angle;
A cutting device that cuts a portion to be cut by moving the processing tool in the axial direction on the processing start surface side from the initial position for processing by the moving distance at the cutting phase angle. A balance correction device is provided.

  According to the present invention described above, the inclination of the machining start surface of the part to be cut with respect to the axial direction is measured, and based on the inclination, the cutting phase angle, and the cutting depth, the machining tool is measured from the initial position for machining at the cutting phase angle. A moving distance for moving the workpiece in the axial direction is obtained, and the cutting tool is cut by moving the processing tool in the axial direction on the machining start surface side from the initial position for machining by this moving distance. Therefore, it is possible to perform cutting in consideration of the inclination of the portion to be cut. As a result, the accuracy of balance correction can be improved.

(A) is the schematic of the conventional balance correction apparatus, (B) is explanatory drawing which expanded a part of (A), (C) is the figure which expanded a part of (A) However, it is an explanatory view showing a conventional problem. (A) shows the balance correction apparatus by embodiment of this invention, (B) is a BB arrow line view of (A), (C) is a CC arrow line view of (A). It is. In FIG. 2 (A), it is the figure which abbreviate | omitted illustration of the contact detection part and showed the processing tool. It is explanatory drawing which expanded a part of FIG. 2 (A). 5 is a flowchart illustrating a balance correction method according to an embodiment of the present invention. The case where the balance correction apparatus by embodiment of this invention is applied to a supercharger is shown.

  Embodiments of 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.

  The balance correction apparatus 10 according to the embodiment of the present invention partially cuts the cutting target portion 5a of the rotating body 5 in the axial direction of the radial bearing 4 in a state where the rotating body 5 of the rotating machine is supported by the radial bearing 4. This is a device that reduces (eliminates) the unbalance of the rotating body 5.

  FIG. 2A shows the overall configuration of the balance correction apparatus 10. FIG. 2B is a view taken along arrow BB in FIG. FIG. 2C is a CC arrow view of FIG. 2A, and shows only a contact detection unit 15a, a processing tool 13a, and a movable unit 15b3 described later. FIG. 3 corresponds to FIG. 2A, but is a diagram illustrating the processing tool 13a with the illustration of the contact detection unit 15a omitted for the sake of explanation.

  In FIG. 1A, reference numeral 3 denotes a housing in which a radial bearing 4 is provided. The housing 3 may be the housing of the rotating machine itself, or may be a dedicated housing for balance correction. Reference numeral 6 denotes a support that supports the housing 3. Further, in FIG. 2 (A), at the time of balance correction, as in the case of FIG. 1 (A), the lubricating oil is supplied to each radial bearing 4 from above (the upper side of FIG. 1 (A)), and the radial bearings. 4 is discharged downward (lower side in FIG. 1A).

In the present application, the axial direction refers to the direction of the central axis C of the radial bearing 4 that supports the rotating body 5 in the radial direction when measuring the inclination of the cutting target portion 5a and when cutting the cutting target portion 5a. Means. The radial direction is a direction with respect to the axial direction.
In the present application, the phase angle means a position on the rotating body in the direction around the axis of the rotating body. The cutting phase angle means a phase angle at which the cutting target portion 5a is cut in the axial direction in order to remove unbalance existing in the rotating body 5. The cutting depth means the depth of the cutting.

  The balance correction device 10 includes an inclination measurement device 9, a drive amount determination device 11, and a cutting device 13.

  The inclination measuring device 9 measures the inclination of the machining start surface 7 (normal line of the machining start surface 7), which is the surface (in this example, a plane) of the cutting target portion 5a with respect to the axial direction. In the present embodiment, the inclination measuring device 9 includes a distance measuring device 15, a rotation angle changing device 16, a rotation angle sensor 18, and a calculation unit 17.

  The distance measurement device 15 includes a contact detection unit 15a, a drive device 15b, a measurement unit 15c, and a control unit 15d.

  The contact detection unit 15a detects contact with the processing start surface 7, and outputs a contact signal to that effect to the measurement unit 15c.

  The driving device 15b moves the contact detection unit 15a in the axial direction from the initial position for measurement to the machining start surface 7. In the example of FIG. 2, the driving device 15b moves the first movable portion 15b1 movable in the Z direction in FIG. 2 (vertical direction in FIG. 2) and the first movable portion 15b1 in the Z direction in FIG. A first drive section (not shown) and a second attached to the first movable section 15b1 and movable in the Y direction of FIG. 2 (direction perpendicular to the paper surface of FIG. 2) with respect to the first movable section 15b1 The second movable portion 15b2, the second movable portion 15b2 that moves the second movable portion 15b2 in the Y direction in FIG. 2 with respect to the first movable portion 15b1, and the second movable portion 15b2. The third movable portion 15b3 that can move in the X direction in FIG. 2 (left and right direction in FIG. 2) with respect to the second movable portion 15b2, and the third movable portion 15b3 in FIG. 2 with respect to the second movable portion 15b2. And a third drive unit (not shown) that moves in the X direction.

  The measurement unit 15c measures the distance that the contact detection unit 15a is moved in the axial direction from the initial position for measurement by the driving device 15b. The measurement unit 15c may be configured by appropriate means (for example, a linear scale).

The measurement unit 15c receives from the control unit 15d a measurement start signal indicating that the contact detection unit 15a has been positioned at the initial measurement position, and receives a contact signal indicating that the contact detection unit 15a has contacted the processing start surface 7. Receive from. The measurement unit 15c uses, as an axial distance, the distance that the contact detection unit 15a is moved in the axial direction on the machining start surface 7 side from the initial position for measurement from the time when the measurement start signal is received until the time when the contact signal is received. measure.
The control unit 15d controls the drive device 15b.

  The rotation angle changing device 16 includes a gripping device 16a and a rotation driving device 16b. The gripping device 16 a is disposed coaxially with the rotating body 5 and grips the end of the rotating body 5. The gripping device 16a may be a collet chuck, for example. The rotation driving device 16b rotates the gripping device 16a that grips the end of the rotating body 5 around the central axis C, thereby rotating the rotating body 5. The rotation drive device 16b may be configured by a servo motor as shown in FIG. 2, for example. A pinion 16b1 is fixed to the output shaft of the servo motor 16b. A rotating shaft 16a1 is coupled to the gripping device 16a, and the rotating shaft 16a1 is supported so as to be rotatable around the central axis C by a bearing (not shown). A gear 16a2 that meshes with the pinion 16b1 is fixed to the rotary shaft 16a1. The servo motor 16b rotates the gripping device 16a via the pinion 16b1 and the gear 16a2.

  The rotation angle sensor 18 measures the rotation angle of the rotating body 5. This rotation angle indicates the position of the rotating body 5 around the axis C of the reference phase angle (reference point). The rotation angle sensor 18 is disposed at a position facing the machining start surface 7 in the example of FIG. 2A. However, when the distance measuring device 15 or the cutting device 13 is used, the distance measurement is performed by an appropriate means. It may be retracted to a position where it does not interfere with the device 15 or the cutting device 13.

  The rotation angle changing device 16 changes the rotation angle of the rotating body 5 into a plurality of values, and the distance measuring device 15 measures the above-described axial distance for each value. In this measurement, in the present embodiment, the above-described initial positions for measurement are the same for the above-described X direction, Y direction, and Z direction among a plurality of values of the rotation angle.

  The computing unit 17 receives a plurality of the axial distances from the measuring unit 15c, receives a plurality of rotation angles from the rotation angle sensor 18, and each of the relations between the plurality of axial distances and the plurality of rotation angles corresponding to each other. Based on the above, the inclination of the machining start surface 7 with respect to the axial direction is calculated as in step S25 described later. Specifically, the calculation unit 17 calculates the tilt direction and tilt angle of the machining start surface 7 with respect to the axial direction.

Based on the cutting phase angle, the cutting depth, and the measured inclination, the drive amount determination device 11 obtains a moving distance L1 for moving the processing tool 13a in the axial direction from the processing initial position at the cutting phase angle. The drive amount determination device 11 calculates the movement distance L1 by the following approximate expression (2), for example.

L1≈Xsin θ + L0 (2)

In this equation, X, θ, and L0 are shown in FIG. X is a radial distance from a straight line including the central axis C of the radial bearing 4 to the initial machining position Pr. θ is an angle formed by a straight line extending from the central axis C to the cutting phase angle along the machining start surface 7 and a plane orthogonal to the central axis C. L0 is the distance from the processing initial position Pr to the processing start surface 7 when the processing start surface 7 is not tilted. In FIG. 4, the broken line indicates the rotating body 5 in a state where it is not inclined in the axial direction (its own shaft faces the axial direction of the radial bearing 4).

  The cutting device 13 cuts the cutting target portion 5a by moving the processing tool 13a in the axial direction on the processing start surface 7 side from the processing initial position Pr by the moving distance at the cutting phase angle. Thereby, the cutting target portion 5a is cut by the cutting depth at the cutting phase angle. In the example of FIG. 3, the processing tool 13a is an end mill that is driven to rotate about its own axis. The shaft of the end mill 13 is parallel to the axial direction of the radial bearing 4.

In the example of FIG. 3, the cutting device 13 includes the processing tool 13a, the first to third movable parts 15b1, 15b2, and 15b3 described above, the first to third drive parts described above, and the control part 15d described above. It consists of.
The processing tool (end mill) 13a is installed in the 3rd movable part 15b3 in the example of FIG. Therefore, the end mill 13a can be moved in the axial direction on the machining start surface 7 side by the moving distance from the machining initial position Pr by the driving device 15b. In this case, the end mill 13 is installed at a position shifted in the Y direction in FIGS. 2A and 2C from the contact detection unit 15a in the third movable unit 15b3. Thereby, when using the end mill 13, the contact detection part 15a does not interfere with the cutting object part 5a, and when using the contact detection part 15a, the end mill 13 does not interfere with the cutting object part 5a.
The movement of the processing tool 13a is controlled by the control unit 15d in the example of FIG. That is, the movement distance is input to the control unit 15 from the drive amount determination device 11, and the control unit 15d is configured to cut the processing tool 13a from the initial position for machining Pr by the movement distance by the movement distance based on the movement distance. The drive device 15b is controlled so as to move to the 5a side.

  Preferably, when the processing tool 13a cuts the cutting target portion 5a (that is, when a cutting step S4 described later) is performed, and when the distance measuring device 15 measures the axial distance (that is, step S22 described later). When performing, a fitting member 22 is provided to be fitted to the end portion of the rotating body 5 in the axial direction (in the example of FIG. 2, the end portion on the processing start surface 7 side). The fitting member 22 may be a rod-shaped member having a shape with a tapered tip. In this case, an insertion hole 7a opened in the axial direction (the right direction in FIG. 2A) is provided at the end of the rotating body 5 (the processing start surface 7 in the example of FIG. 2). The insertion hole 7 a has a shape that matches the shape of the tip of the fitting member 22. That is, the insertion hole 7a has a shape tapered in the depth direction (axial direction). The front end portion of the fitting member 22 is inserted into the insertion hole 7 a in the axial direction, so that the fitting member 22 is fitted to the end portion of the rotating body 5.

  Using the balance correction apparatus 10 described above, the balance correction method according to the embodiment of the present invention can be performed. In this balance correction method, with the rotating body 5 supported by the radial bearing 4, the cutting target portion 5 a of the rotating body 5 is partially cut in the axial direction of the radial bearing 4, thereby unbalanced the rotating body 5. Reduce.

  FIG. 5 illustrates a balance correction method according to an embodiment of the present invention. The balance correction method includes a cutting data acquisition step S1, an inclination measurement step S2, a movement distance acquisition step S3, and a cutting step S4.

In the cutting data acquisition step S1, a cutting phase angle and a cutting depth are obtained in advance. In the present embodiment, the cutting phase angle is an unbalance phase angle at which an unbalance exists in the rotating body 5, and the cutting depth is a depth for removing the unbalance amount U. The unbalance amount U can be expressed by U = r × m. Here, r is the radial distance between the straight line including the central axis C of the radial bearing 4 and the initial processing position Pr. m is mass. When the processing start surface 7 is not inclined with respect to the axial direction, the cutting depth can be removed from the cutting target portion 5a by a mass m by cutting the cutting target portion 5a by the depth from the processing start surface 7. Value. The cutting depth can be obtained in advance based on m, the density of the cutting target portion 5a, the dimensions of the processing tool 13a, and the shape of the cutting target portion 5a if necessary.
Such a method of obtaining the cutting phase angle and the cutting depth (unbalance phase angle and unbalance amount) is described in Patent Documents 1 and 2, for example.

  In the inclination measuring step S2, the inclination measuring device 9 measures the inclination of the machining start surface 7 with respect to the axial direction. The inclination measurement step S2 includes steps S21 to S24.

In step S <b> 21, the rotation angle of the rotating body 5 is measured by the rotation angle sensor 18.
In step S22, the axial distance from the initial position for measurement to the measured position on the machining start surface 7 is measured by the distance measuring device 15 while maintaining the rotation angle of the rotating body 5 in step S21.
In step S23, it is determined whether the number of times that step S22 has been performed has reached the set number. If this determination is NO, the process proceeds to step S24, and if this determination is YES, the process proceeds to step S25. The set number is an integer greater than or equal to 3 (however, the rotation angles measured in step S21 three times or more are different from each other). In this way, by repeating steps S21, S22, and S24, the relationship between the plurality of rotation angles and the plurality of axial distances respectively corresponding to each other is acquired.
In step S24, the gripping device 16a that grips the rotating body 5 is rotated by the rotation driving device 16b. Thereby, the rotating body 5 is rotated, and the relative position between the reference point on the rotating body 5 and the distance measuring device 15 (that is, the contact detection unit 15a) is changed in the direction around the axis of the rotating body 5. In step S24, the rotation of the rotating body 5 by the rotation driving device 16b is stopped so that the relative position thus changed is maintained constant. After step S24 is performed, the process returns to step S21. The relative position changed in step S24 is kept constant in the returned steps S21 and S22.
In step S25, based on the relationship between the plurality of rotation angles and the plurality of axial distances acquired by repeating steps S21, S22, and S24, the calculation unit 17 causes the inclination of the machining start surface 7 to the axial direction. Is calculated.

  Preferably, step S22 is performed as follows. First, in a state where one end portion in the axial direction of the rotating body 5 is gripped by the gripping device 16a, the other end portion in the axial direction of the rotating body 5 is fitted to the fitting member 22 so that the other end portion is pivoted. Do not shift in the radial direction with respect to the direction. At the same time, the fitting member 22 is pressed in an axial direction from the other end portion to the one end portion by an appropriate means, thereby preventing the rotating body 5 from being inclined from the axial direction. In this state, as described above, the distance measuring device 15 measures the axial distance from the initial position for measurement to the measurement position on the processing start surface 7.

  In the movement distance acquisition step S3, the driving amount determination device 11 moves the processing tool 13a from the processing initial position Pr based on the cutting phase angle and cutting depth obtained in step S1 and the inclination measured in step S2. The above-mentioned movement distance L1 to be moved in the axial direction is calculated.

  In the cutting step S4, the cutting tool portion 5a is moved in the axial direction from the processing initial position Pr by the moving distance at the cutting phase angle with respect to the reference phase angle (reference point) in the rotating body 5, thereby cutting the target portion 5a. To cut. Thereby, the cutting target portion 5a can be cut from the machining start surface 7 in the axial direction by the cutting depth at the cutting phase angle. The initial machining position Pr is specified by a preset axial position, a preset radial position, and a cutting phase angle. In the cutting step S4, the position of the reference phase angle in the rotating body 5 is measured by the rotation angle sensor 18 about the axis C, and based on the measured value, the control unit 15d determines the cutting phase with respect to the reference phase angle. The processing tool 13a is positioned at the processing initial position Pr corresponding to the corner.

  Preferably, step S4 is performed as follows. First, the fitting member 22 is fitted to the other axial end of the rotating body 5 in a state where one end of the rotating body 5 in the axial direction is gripped by the gripping device 16a so that the rotating body 5 does not rotate. This prevents the other end from shifting in the radial direction with respect to the axial direction. At the same time, by pressing the fitting member 22 fitted to the other end portion from the other end portion to the one end portion by an appropriate means, the rotating body 5 is prevented from being inclined from the axial direction. . In this state, as described above, the cutting target portion 5a is cut by moving the processing tool 13a in the axial direction from the processing initial position Pr by the moving distance at the cutting phase angle.

[Example]
FIG. 6 shows a case where the balance correction device 10 according to the above-described embodiment is applied to a supercharger 20 as a rotating machine.

  As shown in FIG. 6, the rotating body 5 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. The supercharger 20 includes a housing (bearing housing) 3 in which a radial bearing 4 that rotatably supports the rotating body 5 is incorporated. The supercharger 20 includes a turbine housing 29 that houses the turbine blades 21 therein, and a compressor housing (removed in FIG. 6) that houses the compressor blades 23 inside. The turbine housing 29 is formed with a flow path (scroll) through which a fluid that rotationally drives the turbine blades 21 during unbalance measurement. The turbine housing 29 is attached to the inside of the support body 6. 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 6 through the holes 6 a of the support 6. 6 is configured.

  Further, the support 6 supports the bearing housing 3 via the turbine housing 29 or directly. In FIG. 6, the cutting target portion 5a of the rotating body 5 is at the end portion on the compressor blade 23 side, and is a nut in this example. In this case, the outer peripheral portion of the nut 5a is cut in the above-described cutting step S4.

  The gripping device 16 a grips an end portion of the rotating body 5 on the turbine blade 21 side through a hole 6 a that is formed in the support body 6 and opens in the axial direction. The gripping device 16a does not grip the end during unbalance measurement.

  Further, the insertion hole 7 a is formed in the end surface 26 a of the male screw portion 26 in which the nut 5 a is screwed in the rotating body 5.

  In FIG. 6, other points of the balance correction device 10 and the balance correction method may be the same as those in the above-described embodiment.

  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, two or more change examples that can be combined selected from the following modification examples 1 to 5 may be combined, or any one of the following modification examples 1 to 5 may be employed alone. In this case, the other points may be the same as described above.

(Modification 1)
In the above-described embodiment, the distance measurement device 15 uses the contact detection unit 15a to measure the axial distance from the measurement initial position to the measurement position on the processing start surface 7 in the axial direction. Is not limited to this. That is, the distance measuring device 15 measures the axial distance from the initial position for measurement to the measured position on the processing start surface 7 in the axial direction without contact (for example, using an imaging device or a laser distance meter). May be. In this case, the other points may be the same as described above.

(Modification 2)
The inclination measuring device 9 may have an imaging device (for example, a CCD camera) instead of the distance measuring device 15. In this case, an image of the processing start surface 7 when not tilted is acquired in advance as a reference image, and in step S2, an image of the processing start surface 7 is acquired by the imaging device. The inclination of the processing start surface 7 may be obtained by comparing the reference image.

(Modification 3)
In the above-described embodiment, the cutting phase angle coincides with the unbalanced phase angle, but the present invention is not limited to this. That is, in order to remove the above-described unbalance amount U, the cutting target portion 5a is cut in the axial direction at a plurality of phase angles, and as a whole, the unbalance amount U is removed at the unbalance phase angle. You may make it do. In this case, the balance correction apparatus and method of the present invention may be applied for each cutting phase angle, and the other points may be the same as described above.

(Modification 4)
In the above-described embodiment, the rotating body 5 is rotated in step S24. Instead, the position of the distance measuring device 15 (contact detection unit 15a) (that is, the initial position for measurement) is changed to the above-described driving device. It may be changed in the direction around the axis C by 15b. In this case, in step S21, the initial position for measurement with respect to the direction around the axis C is measured by an appropriate means. In step S25, the measurement initial position measured in each step S21 and the measurement initial position are measured in each step S22. Based on the relationship between the plurality of axial distances, the inclination of the machining start surface 7 is obtained. In step S2, the measurement initial position in a direction other than the direction around the axis C is preferably kept constant, and the rotating body 5 is preferably held by the holding device 16a so as not to rotate.

(Modification 5)
In the above-described embodiment, the processing tool 13a and the contact detection unit 15a are moved by the common driving device 15b. However, the processing tool 13a and the contact detection unit 15a may be moved by separate driving devices. In this case, the contact detection unit 15a may be moved only in the axial direction by the driving device.

3 Housing, 4 Radial bearing, 5 Rotating body, 5a Cutting target part, 6 Support body, 6a Hole, 7 Machining start surface, 9 Tilt measuring device, 10 Balance correction device, 11 Drive amount determining device, 13 Cutting device, 13a Tool, 15 distance measurement device, 15a contact detection unit, 15b drive device, 15c measurement unit, 15d control unit, 15b1 first movable unit, 15b2 second movable unit, 15b3 third movable unit, 16 rotation angle changing device , 16a gripping device, 16b rotational drive device, 17 calculating unit, 18 rotation angle sensor, 19 gripping device, 20 turbocharger, 21 turbine blade, 22 fitting member, 23 compressor blade, 25 rotating shaft, 29 turbine housing

Claims (5)

A balance correction method for reducing unbalance of a rotating body by partially cutting a cutting target portion of the rotating body in the axial direction of the radial bearing while the rotating body is supported by a radial bearing,
The position on the rotating body in the direction around the axis of the rotating body is a phase angle, the phase angle at which the cutting target portion is cut in the axial direction in order to remove the unbalance existing in the rotating body, and the depth of the cutting, respectively Cutting data acquisition step to obtain in advance as cutting phase angle and cutting depth;
An inclination measuring step for measuring an inclination of a machining start surface of the cutting target portion with respect to the axial direction;
Based on the cutting phase angle, the cutting depth and the inclination, a moving distance obtaining step for obtaining a moving distance for moving the processing tool in the axial direction from the initial processing position at the cutting phase angle;
A cutting step of cutting a cutting target portion by moving a processing tool in the axial direction on the processing start surface side from the initial position for processing by the moving distance at the cutting phase angle. How to correct the balance. In the inclination measuring step,
(A) Measure the rotation angle of the rotating body,
(B) An axial distance from an initial position for measurement to a measurement position on the machining start surface is measured in the axial direction using a distance measuring device,
(C) By rotating the rotating body, the relative position between the reference point on the rotating body and the distance measuring device is changed in the direction around the axis of the rotating body,
By repeating the steps (A), (B), and (C), the relationship between the plurality of rotation angles and the plurality of axial distances is acquired, and the inclination of the machining start surface is obtained based on the relationship. The balance correction method according to claim 1. In the inclination measuring step,
(A) Measure the initial position for measurement of the distance measuring device in the direction around the axis of the rotating body,
(B) The axial distance from the initial position for measurement to the position to be measured on the machining start surface is measured in the axial direction using the distance measuring device,
(C) changing the initial position for measurement of the distance measuring device in the direction around the axis of the rotating body,
By repeating (A), (B), and (C), the relationship between the plurality of initial positions for measurement in the direction around the axis of the rotating body and the plurality of axial distances is acquired, and based on this relationship The balance correction method according to claim 1, wherein the inclination of the machining start surface is obtained. In (A) above,
In a state where one end portion in the axial direction of the rotating body is gripped by a gripping device, a fitting member is fitted to the other end portion in the axial direction of the rotating body, so that the other end portion has a radius with respect to the axial direction. The fitting member is pressed toward the one end from the other end,
The axial distance from the initial position for measurement to the measured position on the machining start surface in this state is measured in the axial direction using the distance measuring device. The balance correction method described. In a state where the rotating body is supported by a radial bearing, the balance correction device reduces the unbalance of the rotating body by partially cutting the cutting target portion of the rotating body in the axial direction of the radial bearing,
The position on the rotating body in the direction around the axis of the rotating body is a phase angle, the phase angle at which the cutting target portion is cut in the axial direction in order to remove the unbalance existing in the rotating body, and the depth of the cutting, respectively , Cutting phase angle and cutting depth,
An inclination measuring device for measuring the inclination of the machining start surface of the cutting target portion with respect to the axial direction;
Based on the cutting phase angle, the cutting depth, and the inclination, a drive amount determination device that obtains a moving distance for moving the processing tool in the axial direction from the initial processing position at the cutting phase angle;
A cutting device that cuts a portion to be cut by moving the processing tool in the axial direction on the processing start surface side from the initial position for processing by the moving distance at the cutting phase angle. Balance correction device to do.