JP6112353B2 - Load measurement method - Google Patents

Description

  The present invention relates to a load measuring method for measuring a rolling element load generated on a rolling surface of a bearing using ultrasonic waves transmitted from a plurality of ultrasonic probes.

  Patent Documents 1 and 2 describe an ultrasonic load measuring method for measuring ball support loads at various locations of a bearing using an array type probe. The array-type probe has a large number of ultrasonic probes arranged along the outer periphery of the bearing housing. Pulse ultrasonic waves are transmitted from the ultrasonic probes at the timing when the balls of the ultrasonic probes pass. At this time, the distribution of the ball support load in the bearing is determined based on the echo height (intensity) of the reflected wave reflected by the bearing raceway surface.

JP 2006-214905 A JP 2006-214904 A

The inventors of the present application use an ultrasonic load measuring method as described above to convert one ultrasonic beam formed by a probe array (array-type probe) into a rolling surface (orbital surface) of a bearing. ) And scanning the irradiation position of the ultrasonic beam on the rolling surface, the distribution of the rolling element load (rolling body load) generated on the rolling surface is being studied.
However, there is no technique for confirming whether or not the irradiation position of the ultrasonic beam is at the intended position. Since the ultrasonic waves cannot be captured with the naked eye, the irradiation position of the ultrasonic beam may be deviated from the intended position. In this case, the measurement accuracy of the rolling element load may be reduced. In order to improve the measurement accuracy of the rolling element load, it is required to check whether the irradiation position of the ultrasonic beam is at the intended position and to calibrate the deviation when it is displaced from the intended position. Yes.

  Accordingly, an object of the present invention is to provide a load measuring method capable of calibrating the deviation of the irradiation position of the ultrasonic beam and thereby improving the measurement accuracy of the rolling element load.

  In order to achieve the above object, an invention according to claim 1 is directed to an inner ring using an ultrasonic measuring device (100) including a probe array (2) having a plurality of ultrasonic probes (5). (20) and the rolling surface (12) of the bearing (1) having a rolling element (30) for rolling between the concave rolling surfaces (22, 12) of the outer ring (10), The rolling is performed based on the intensity of the reflected wave applied to the ultrasonic probe at that time by irradiating an ultrasonic beam (BM) formed by ultrasonic transmission from a plurality of ultrasonic probes. A load measuring method for measuring a load of the rolling element generated on a surface, having a calibration recess (24), and having a pressing surface (23A) along the rolling surface (23) Is pressed against the rolling surface so that the pressing surface including the calibration recess comes into contact with the rolling surface. And an ultrasonic beam formed by transmitting ultrasonic waves from the plurality of ultrasonic probes to the rolling surface. The calibration measurement step for measuring the intensity of the reflected wave applied to the ultrasonic probe, the pressing step and the calibration measurement step are performed in parallel, and the irradiation position of the ultrasonic beam is changed. A scanning step for measurement that scans within the moving surface; and a reference position calibration step that calibrates a reference position for irradiation of the ultrasonic beam based on the measurement result of the intensity of the reflected wave. Provide a load measurement method.

In this section, the alphanumeric characters in parentheses represent reference signs of corresponding components in the embodiments described later, but the scope of the claims is not limited to the embodiments by these reference numerals.
As described in claim 2, the rolling surface has a cylindrical surface shape, and the pressing surface of the calibration jig has a cylindrical surface (23A) having a smaller radius of curvature than the rolling surface. In addition, the calibration recess may be formed in the cylindrical surface.

According to a third aspect of the present invention, the calibration jig has an outer cylindrical shape, and the end surface (23B) of the calibration jig is aligned in the circumferential direction of the calibration jig. A mark (25) for indicating the position of the calibration recess may be provided.
Furthermore, as described in claim 4, a plurality of the calibration recesses are provided, and the plurality of calibration recesses may be arranged at regular intervals and in a lattice shape.

  By using a calibration jig, it is possible to detect the presence or absence of deviation of the irradiation position of the ultrasonic beam. The measurement accuracy of the rolling element load can be improved by calibrating the deviation of the irradiation position of the ultrasonic beam.

It is a figure showing a schematic structure of an ultrasonic measuring device for carrying out a load distribution measuring method to which a load measuring method concerning one embodiment of the present invention is applied. It is a top view of the ultrasonic array shown in FIG. It is a block diagram which shows the main electrical structures of the ultrasonic measuring device shown in FIG. It is a figure explaining the basic principle of measurement of rolling element load using an ultrasonic wave. It is a graph which shows the change of the intensity | strength of a reflected wave. It is a figure for demonstrating the phased array technique using an ultrasonic array. It is a perspective view which shows the structure of the wedge shown in FIG. It is sectional drawing which shows the structure of the constant velocity joint which is a measuring object of a load distribution measuring method. It is a side view which shows the structure of the constant velocity joint which is a measuring object of a load distribution measuring method. It is a figure which shows the beam irradiation area in an outer ring raceway surface. It is a figure which shows the structure of the jig | tool for calibration. It is a figure which shows the state which has arrange | positioned the jig | tool for calibration in the space between an inner ring raceway surface and an outer ring raceway surface.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an ultrasonic measurement apparatus 100 for implementing a load distribution measurement method to which a load measurement method according to an embodiment of the present invention is applied. FIG. 5A shows a state where the constant velocity joint (bearing) 1 to be measured is attached to the outer ring raceway surface (rolling surface) 12. FIG. It is a schematic diagram which shows the state which has irradiated the sound beam BM.

  The ultrasonic measurement apparatus 100 is configured to load the rolling element 30 acting on the outer ring raceway surface 12 of the outer ring 10 of the constant velocity joint 1 (hereinafter referred to as “rolling element load” during rotation of the constant velocity joint 1 which is an example of a rotating device. Is a device for measuring the load distribution. The ultrasonic measurement apparatus 100 includes a plate-like probe array 2 in which a large number (plural) of ultrasonic probes 5 are arranged, a beam forming circuit 3 for forming one ultrasonic beam BM, On the outer ring raceway surface 12 of the outer ring 10 based on the wedge 4 for coupling the ultrasonic energy from the ultrasonic probe 5 to the outer ring 10 and the intensity of the reflected wave applied to the ultrasonic probe 5, And a processing device 9 for measuring the load distribution of the rolling element load.

In addition, although the case where the probe array 2 is curving in FIG.1 (b) is illustrated on the relationship of illustration, in this embodiment, as shown to Fig.1 (a), a probe array is shown. 2 has a flat plate shape.
FIG. 2 is a plan view of the probe array 2. The probe array 2 is a two-dimensional array, and a large number of small, rectangular ultrasonic probes 5 are arranged in a matrix on a rectangular main body sheet 6. In FIG. 2, 30 ultrasonic probes 5 are arranged in 5 rows and 6 columns, but the number of ultrasonic probes 5 and the matrix configuration can be appropriately changed according to the required resolution. There is no limit (for example, 256 ultrasonic probes 5 can be arranged in 16 rows and 16 columns).

FIG. 3 is a block diagram showing the main electrical configuration of the ultrasonic measurement apparatus 100.
The beam forming circuit 3 includes a large number (a plurality) of transmission / reception circuits 8 and a large number (a plurality of) delay circuits 7. The transmission / reception circuit 8 and the delay circuit 7 are provided for each ultrasonic probe 5 in a one-to-one correspondence. The transmission / reception circuit 8 excites the corresponding ultrasonic probe 5 to vibrate the ultrasonic probe 5 to transmit ultrasonic waves. Further, the transmission / reception circuit 8 receives an ultrasonic wave (reflected wave) applied to the corresponding ultrasonic probe 5.

  The delay circuit 7 is a circuit for delaying the excitation timing of the corresponding ultrasonic probe 5. By controlling the delay circuit 7, only the transmission timing (delay time) of the ultrasonic wave transmitted from the corresponding ultrasonic probe 5 can be delayed without changing the waveform. Since the delay circuit 7 is provided for each ultrasonic probe 5 in a one-to-one correspondence, the transmission timing of ultrasonic waves can be individually controlled in many ultrasonic probes 5.

  As a result, a single ultrasonic beam BM (see FIG. 1 and the like) can be formed by combining ultrasonic waves transmitted from a large number of ultrasonic probes 5. That is, in the single ultrasonic probe 5, the ultrasonic wave propagates in a small size and a wide angle, but by controlling the transmission timing of a large number of ultrasonic waves by the beam forming circuit 3, from the probe array 2, The ultrasonic wave can be converged at a target irradiation position to form one ultrasonic beam BM (phased array technology).

FIG. 4 is a diagram for explaining the basic principle of measurement of rolling element load using ultrasonic waves.
The ultrasonic wave (incident wave) transmitted from the ultrasonic probe 5 travels straight in the outer ring 10 of the constant velocity joint 1 and reaches the outer ring raceway surface 12. At this time, the ultrasonic wave is reflected by the outer ring raceway surface 12 to become a reflected wave, travels straight through the outer ring 10 again, and is applied to the same ultrasonic probe 5 that has been transmitted. In this case, if the outer surface of the rolling element 30 is in contact with the ultrasonic irradiation position of the outer ring raceway surface 12, the reflected wave is attenuated because there is a wave (transmitted wave) that passes through the rolling element 30, and the reflected wave If the outer surface of the rolling element 30 is not in contact with the ultrasonic wave irradiation position of the outer ring raceway surface 12, the reflected wave is not attenuated and the intensity of the reflected wave remains at the original strength. is there.

  FIG. 5 is a graph showing changes in the intensity of the reflected wave. The case where the outer surface of the rolling element 30 is in contact with the ultrasonic irradiation position on the outer ring raceway surface 12 is indicated by a broken line (passing through the rolling element), and the outer surface of the rolling element 30 is positioned at the ultrasonic irradiation position on the outer ring raceway surface 12. The solid line shows the case where no contact is made (no rolling element). From FIG. 5, when the outer surface of the rolling element 30 is in contact with the ultrasonic irradiation position on the outer ring raceway surface 12, the reflected wave is attenuated compared to the case where the outer surface of the rolling element 30 is not in contact. It can be seen that the intensity (echo height) of the reflected wave is relatively low.

FIG. 6 is a diagram for explaining a phased array technique using the probe array 2. 3 and 6, the ultrasonic measurement apparatus 100 (see FIG. 1) employs a phased array technique for controlling the transmission (reception) timing of a large number of ultrasonic waves by the beam forming circuit 3 as described above. The
In the probe array 2, the ultrasonic beam BM having a predetermined mode is formed by controlling the transmission timing of the predetermined ultrasonic probe 5 among all the ultrasonic probes 5 with a specific pattern.

As an example of the phased array technology, there are those shown in FIGS. 6 (a) to 6 (c).
In the angle scanning shown in FIG. 6A, the emission direction of the ultrasonic wave can be controlled by controlling the transmission timing of each ultrasonic wave. Therefore, the incident angle of the ultrasonic wave with respect to the outer ring raceway surface 12 (see FIG. 1 and the like) can be controlled by such angle scanning.
In the focus scanning shown in FIG. 6B, the ultrasonic waves transmitted from the plurality of ultrasonic probes 5 are collected at one focal position F by controlling the transmission timing of each ultrasonic wave. Thereby, one ultrasonic beam BM can be formed. And by such focus scanning, the distance (focal length) and size (focus size) of the focal position F of the ultrasonic beam BM can be controlled.

  In the linear scanning shown in FIG. 6C, a group of ultrasonic probes 5 for forming (transmitting) one ultrasonic beam BM in a predetermined form by controlling the transmission timing of each ultrasonic wave. In order. Specifically, a group G1 consisting of a plurality of adjacent (five in FIG. 6C) ultrasonic probes 5 is superposed in a predetermined direction from the predetermined plurality of ultrasonic probes 5. A group G2,..., Group G10 consisting of the same number of ultrasonic probes 5 shifted by 51 acoustic probes is shifted one by one. Thereby, the focal position F can be moved without directly moving the ultrasonic probe 5.

Combining the scans as shown in FIGS. 6 (a) to 6 (c) has an arbitrary incident angle and is collected at a predetermined focal position F (and has an arbitrary focal length and focal size). ) Ultrasonic beam BM can be created.
FIG. 7 is a perspective view showing the configuration of the wedge 4. The wedge 4 having a three-dimensional shape has a cylindrical surface, and has a bottom surface 14 that is in close contact with the outer peripheral surface of the outer ring 10 and a top surface 15 that is a flat flat inclined surface, and is composed of polystyrene or the like. It is formed using a resin material. The probe array 2 is fixed to the upper surface 15 of the wedge 4 with the mounting surface of the ultrasonic probe 5 facing downward (see FIG. 1). In this fixed state, the mounting surfaces of all the ultrasonic probes 5 are in close contact with the upper surface 15 of the wedge 4.

When measuring the rolling element load of the outer ring 10, the wedge 4 is fixed to the outer peripheral surface of the outer ring 10 so that the entire area of the bottom surface 14 is in close contact with the outer peripheral surface of the outer ring 10. In this state, the ultrasonic wave emitted from each ultrasonic probe 5 propagates from the wedge 4 to the outer ring 10.
As shown in FIG. 1, the processing device 9 includes a beam transmission control unit 16 that controls each transmission / reception circuit 8 of the beam forming circuit 3 to transmit ultrasonic waves, and a reflection received by each ultrasonic probe 5. It has a load distribution calculation unit 17 that calculates the rolling element load on the outer ring raceway surface 12 based on the magnitude of the wave, and is configured using a personal computer or the like. Based on irradiation reference position information 18 (information of a reference position (beam irradiation reference position) for irradiation of the ultrasonic beam BM) stored in a memory (not shown), the beam transmission control unit 16 12, the irradiation position of the ultrasonic beam BM is determined.

FIG. 8 is a cross-sectional view illustrating a configuration of the constant velocity joint 1 that is a measurement target of the load distribution measurement method.
The constant velocity joint 1 includes a cup-shaped outer ring 10, an annular inner ring 20 disposed inside the outer ring 10, and a plurality (for example, six) interposed between the outer ring 10 and the inner ring 20 so as to be able to roll. ), A retainer 40 for holding the rolling element 30 between the outer ring 10 and the inner ring 20, and a shaft 50 provided so as to be integrally rotatable with the inner ring 20. This is a ball type constant velocity joint (generally also called “Zepper type constant velocity joint”).

A plurality of outer ring ball grooves 11 extending in the axial direction of the outer ring 10 (left and right direction in FIG. 8) are provided at equal intervals in the circumferential direction of the outer ring 10 (for example, six) on the inner peripheral surface of the cylindrical portion of the outer ring 10. Is formed. The cross-sectional shape orthogonal to the rotation axis of the outer ring 10 in each outer ring ball groove 11 is substantially arc-shaped.
A plurality of (for example, six) inner ring ball grooves 21 extending in the inner ring rotating shaft direction (left and right direction in FIG. 8) are formed at equal intervals in the circumferential direction of the inner ring rotating shaft. The cross-sectional shape orthogonal to the inner ring rotation axis in each inner ring ball groove 21 is substantially circular arc concave. Each inner ring ball groove 21 is positioned so as to face the corresponding outer ring ball groove 11. An inner spline 22 is formed on the inner peripheral surface of the inner ring 20.

  Each rolling element 30 is fitted in the outer ring ball groove 11 of the outer ring 10 on the outer side and in the inner ring ball groove 21 of the inner ring 20 on the inner side. Each rolling element 30 can roll along the outer ring ball groove 11 and the inner ring ball groove 21, and the movement is restricted with respect to the outer ring ball groove 11 and the inner ring ball groove 21 in the circumferential direction. . That is, the outer ring 10 and the inner ring 20 are locked to each other in the circumferential direction by the rolling element 30. In other words, the rolling element 30 plays a role of transmitting a rotational driving force between the outer ring 10 and the inner ring 20.

  The annular cage 40 is disposed between the inner peripheral surface of the outer ring 10 and the outer peripheral surface of the inner ring 20. The inner peripheral surface of the cage 40 is formed in a partially spherical concave shape substantially corresponding to the outermost peripheral surface of the inner ring 20. Further, the outer peripheral surface of the cage 40 is formed in a partially spherical convex shape. The spherical center of the inner peripheral surface and the spherical center of the outer peripheral surface of the cage 40 are offset to the opposite sides by an equal distance in the axial direction with respect to the joint rotation center. The retainer 40 is formed with six opening window portions 41 at equal intervals in the circumferential direction. The same number of the opening window portions 41 as the outer ring ball grooves 11 and the inner ring ball grooves 21 are formed. The outer ring raceway surface 12 defined by the outer ring ball groove 11 and the inner ring raceway surface 22 defined by the inner ring ball groove 21 are each formed of a cylindrical surface having a semicircular cross section. The rolling elements 30 are fitted in the respective opening window portions 41. That is, the holder 40 holds a plurality of rolling elements 30.

An external spline 51 is formed at the end of the shaft 50. The internal spline 22 of the inner ring 20 is press-fitted into the external spline 51.
The outer ring 10 is held by a first chuck mechanism (not shown) or the like. At this time, the inner ring 20 is supported rotatably around the shaft 50 by a second chuck mechanism (not shown) or the like. When the rolling element load of the outer ring 10 is measured, a rotational torque from a rotational torque applying mechanism (not shown) is applied to the inner ring 20 via the shaft 50. Moreover, the magnitude | size of the rotational torque input into the shaft 50 may be fluctuate | varied.

FIG. 9 is a side view showing a configuration of the constant velocity joint 1 which is a measurement target of the load distribution measuring method.
As shown in FIGS. 8 and 9, when the shaft 50 is rotated with the joint angle of the constant velocity joint 1 maintained constant, the inner ring 20 applies precession to the outer ring 10 in a stationary state. It becomes like this. At this time, the rolling element 30 as a transmission member reciprocates once in the outer ring ball groove 11 of the outer ring 10 and the inner ring ball groove 21 of the inner ring 20 during one cycle of precession. That is, the rolling element 30 reciprocates in the left-right direction in FIG. The width of this reciprocating motion changes depending on the joint angle, and increases as the joint angle is increased.

  At this time, the rolling element 30 is pressed against the outer ring raceway surface 12 formed of a cylindrical surface. In this state, the outer peripheral surface of the rolling element 30 is in contact with the outer ring raceway surface 12 via an elliptical contact region 19 (see FIG. 1B) (see also FIG. 10). In this way, by precession applied to the constant velocity joint 1, a load is applied between the outer ring 10 and the rolling element 30 and between the inner ring 20 and the rolling element 30 at a predetermined cycle. Become. The load distribution of the rolling element 30 at this time (the rolling element load) is measured using the load distribution measuring method of the present invention.

Next, the load distribution measuring method of the present invention will be described with reference to FIG. 1, FIG. 2, FIG. 8, and FIG. A rotational torque is input to the shaft 50 in a state where the joint angle of the constant velocity joint 1 is kept constant.
In this state, the beam transmission control unit 16 of the processing device 9 drives the beam forming circuit 3 to irradiate the ultrasonic beam BM to a predetermined position of the predetermined beam irradiation region BMA on the outer ring raceway surface 12. At this time, the incident direction of the ultrasonic beam BM at the predetermined position is the normal direction of the predetermined position. Specifically, the beam transmission control unit 16 determines the irradiation position of the ultrasonic beam BM based on the irradiation reference position information 18.

On the outer ring raceway surface 12, a beam irradiation region BMA irradiated with the ultrasonic beam BM is set.
FIG. 10 is a diagram showing a beam irradiation area BMA on the outer ring raceway surface 12. Referring also to FIG. 10, the beam irradiation area BMA has a rectangular shape, and the beam irradiation area BMA has a number of irradiation area units M1 subdivided in the row direction and the column direction. In other words, the beam irradiation area BMA is divided into a number of irradiation area units M1. The ultrasonic beam BM is irradiated to a predetermined irradiation area unit M1. An elliptical contact area 19 is completely accommodated inside the beam irradiation area BMA.

And with respect to irradiation of the ultrasonic beam BM from the probe array 2 with respect to one irradiation area unit M1, the load distribution calculation part 17 (refer Fig.1 (a)) of the processing apparatus 9 is a reflected wave. The intensity (the total sum of the intensity applied to each ultrasonic probe 5) is obtained. Thereby, the load distribution calculation part 17 can measure the rolling element load in the said irradiation area unit M1.
And after calculating | requiring the intensity | strength of the reflected wave with respect to irradiation of the ultrasonic beam BM to the one irradiation area unit M1, as shown in FIG.6 (c), as shown in FIG.6 (c), the irradiation position (focus position F (FIG. 6)). 6 (b) and FIG. 6 (c)) are moved, the adjacent irradiation region unit M1 is irradiated with the ultrasonic beam BM, and the ultrasonic beam BM is irradiated also in the adjacent irradiation region unit M1. The intensity of the reflected wave with respect to can be obtained, and thereby the rolling element load in the adjacent irradiation region unit M1 can be measured. In the same procedure, the rolling element load in each irradiation area unit M1 is measured with respect to the entire area of the beam irradiation area BMA. Thereby, the load distribution of the rolling element load in the entire beam irradiation region BMA can be measured.

In the load distribution measurement method using such an ultrasonic measurement apparatus 100, the irradiation reference position information 18 (see FIG. 1A) for irradiation with the ultrasonic beam BM is calibrated as described below. Calibration of the irradiation reference position information 18 is a characteristic part of the present invention.
In such calibration, a calibration jig 23 is used.
FIG. 11 is a diagram illustrating the configuration of the calibration jig 23. FIG. 1A is a view seen from the axial direction of the outer ring 10, and FIG. 2B is a view seen from the circumferential direction of the outer ring 10. FIG. 2C shows the relationship between the size of the calibration jig 23 and the outer ring raceway surface 12 of the outer ring 10.

  The calibration jig 23 has an outer cylindrical shape. The radius r0 of the cross-sectional circle of the cylindrical surface (pressing surface) 23A constituting the outer peripheral surface of the calibration jig 23 is slightly smaller than the radius of curvature r1 in the circumferential direction of the outer ring raceway surface 12 (for example, 0. 94 times). The length of the calibration jig 23 in the axial direction is substantially the same as the length of the outer ring raceway surface 12 (inner ring raceway surface 22) in the axial direction (left-right direction shown in FIG. 7).

  A plurality of calibration grooves (calibration recesses) 24 are formed on the cylindrical surface 23 </ b> A of the calibration jig 23. The calibration grooves 24 are, for example, round grooves having a diameter of 1 mm, and are arranged in a lattice shape, two in the circumferential direction and three in the direction along the axial direction (columnar axial direction). ing. Adjacent calibration grooves 24 are separated by w1 (for example, 2 mm) in the circumferential direction, and adjacent calibration grooves 24 are also separated by w1 (for example, 2 mm) in the direction along the axial direction. The depth of each calibration groove 24 may be, for example, 1 mm or more. Markers (marks) 25 are provided on both end surfaces 23B of the calibration jig 23. The marker 25 is used to directly indicate the circumferential position of the calibration groove 24, and is provided in a short straight line extending along the radial direction.

  At the time of calibration of the irradiation reference position information 18 (see FIG. 1A), the operator removes the rolling element 30 from the space between the inner ring raceway surface 22 and the outer ring raceway surface 12 in the constant velocity joint 1 used for measurement. Instead, the calibration jig 23 is accommodated in the space. FIG. 12 shows a state in which the calibration jig 23 is accommodated in the space between the inner ring raceway surface 22 and the outer ring raceway surface 12. In this state, the calibration jig 23 is almost exactly accommodated in the space between the inner ring raceway surface 22 and the outer ring raceway surface 12.

  Then, as shown in FIG. 12, the operator contacts the outer ring raceway surface 12 with the six calibration grooves 24 formed on the cylindrical surface 23 </ b> A while visually checking the marker 25 on the end surface 23 </ b> B of the calibration jig 23. The calibration jig 23 is aligned in the circumferential direction in a predetermined circumferential direction posture. After the alignment, the cylindrical surface 23A of the calibration jig 23 is pressed against the outer ring raceway surface 12 with a predetermined pressure (pressing step). Since the radius r0 of the cross-sectional circle of the cylindrical surface 23A of the calibration jig 23 having an outer cylindrical shape is slightly smaller than the radius of curvature r1 in the circumferential direction of the outer ring raceway surface 12, at this time, the outer ring raceway surface 12 The outer peripheral surface of the rolling element 30 contacts through an elliptical contact area (equivalent to the contact area 19).

  Then, the ultrasonic beam BM is irradiated from the probe array 2 toward a predetermined irradiation area unit M1 included in the beam irradiation area BMA. The incident direction of the ultrasonic beam BM to the irradiation region unit M1 is the normal direction of the predetermined position. In addition, for the irradiation of the ultrasonic beam BM from the probe array 2 with respect to one irradiation region unit M1, the load distribution calculation unit 17 of the processing device 9 generates a reflected wave based on the signal from each transmission / reception circuit 8. Find strength. Based on the reflected wave intensity, the rolling element load in the irradiation region unit M1 is calculated (calibration measurement step). Then, the irradiation position of the ultrasonic beam BM is scanned in the entire area within the beam irradiation area BMA (measurement scanning step). Thereby, the load distribution of the rolling element load in the beam irradiation region BMA can be measured.

  At this time, if the outer surface of the rolling element 30 is in contact with the irradiation region unit M1 (that is, the irradiation position of the ultrasonic beam BM) on the outer ring raceway surface 12, there is a wave (transmitted wave) that passes through the rolling element 30. Therefore, the reflected wave is attenuated and the intensity of the reflected wave is weakened. If the outer surface of the rolling element 30 is not in contact with the irradiation region unit M1 on the outer ring raceway surface 12, the reflected wave is not attenuated, and the intensity of the reflected wave remains the original strength. Therefore, when the irradiation position of the ultrasonic beam BM scans a portion of the beam irradiation area BMA that does not face the calibration groove 24, the intensity of the reflected wave is weak, but the irradiation position of the ultrasonic beam BM is When the position of the beam irradiation area BMA facing the calibration groove 24 is scanned, the intensity of the reflected wave is increased. Therefore, the load distribution calculation unit 17 can easily specify the position facing the calibration groove 24 on the outer ring raceway surface 12. As described above, since the six calibration grooves 24 are aligned with the outer ring raceway surface 12 when the calibration jig 23 is disposed, the relative positions of the six calibration grooves 24 with respect to the outer ring 10 are always constant. is there. Therefore, the load distribution calculation unit 17 can specify the positions of the six calibration grooves 24 in the beam irradiation region BMA, and the reference position defined by the irradiation reference position information 18 is deviated from the intended position. I can grasp.

Thereafter, the irradiation reference position information 18 is calibrated so that the reference position becomes the intended position. Specifically, the load distribution calculation unit 17 updates the irradiation reference position information 18 to the corrected position information (reference position calibration step). Thereby, the deviation of the irradiation position of the ultrasonic beam BM can be calibrated.
In the load distribution measurement using the ultrasonic measuring apparatus 100 after the calibration of the beam irradiation reference position 18, the irradiation position of the ultrasonic beam BM is accurately controlled. Thereby, the measurement precision of rolling element load can be improved.

As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.
In the probe array 2, a large number (multiple) of ultrasonic probes 5 may be arranged in one or a plurality of rows, or a large number (multiple) of the ultrasonic probes 5 are arranged in a multiple ring shape. And they may be arranged radially.

Further, although the calibration recess has been described as a groove, it may be a hole (calibration hole).
Further, although the marker 25 is a straight line, other patterns may be used, and a symbol or the like may be used for the marker 25. Further, the marker 25 may be provided only on one end surface 24B, not on both end surfaces 24B of the calibration jig 23.
Moreover, when the rolling contact surface which the rolling element 30 contacts is a spherical surface, the calibration jig | tool which has an outer spherical surface (for example, spherical body) is employable.

Moreover, although the measuring method of the load distribution of a rolling element load was demonstrated, this invention is not the distribution of a rolling element load, but the load which detects only the rolling element load which arises in one place of the outer ring raceway surface 12 (rolling surface). Can be used for all measurement methods.
In this embodiment, the case where the bearing to be measured is the above-described constant velocity joint 1 has been described as an example, but various other bearings can be measured.

  In addition, various design changes can be made within the scope of matters described in the claims.

DESCRIPTION OF SYMBOLS 1 ... Constant velocity joint (bearing), 2 ... Probe array, 5 ... Ultrasonic probe, 10 ... Outer ring, 12 ... Outer ring raceway surface (rolling surface), 20 ... Inner ring, 22 ... Inner ring raceway surface (Rolling) Moving surface), 23 ... calibration jig, 23A ... cylindrical surface (pressing surface), 23B ... end surface, 24 ... calibration groove (calibration recess), 25 ... marker (mark), 30 ... rolling element, 100 ... Ultrasonic measuring device, BM ... Ultrasonic beam

Claims (4)

The rolling of the bearing having a rolling element for rolling between the concave rolling surfaces of the inner ring and the outer ring using an ultrasonic measuring device including a probe array having a plurality of ultrasonic probes. The surface is irradiated with an ultrasonic beam formed by ultrasonic transmission from the plurality of ultrasonic probes, and the rotation is performed based on the intensity of the reflected wave applied to the ultrasonic probe at that time. A load measuring method for measuring a load of the rolling element generated on a moving surface,
A calibration jig having a calibration recess and having a pressing surface along the rolling surface, and the rolling surface such that the pressing surface including the calibration recess is in contact with the rolling surface. A pressing step that presses against
It is executed in parallel with the pressing step and irradiates the rolling surface with an ultrasonic beam formed by ultrasonic transmission from the plurality of ultrasonic probes, and at that time, the ultrasonic probe A calibration measurement step for measuring the intensity of the reflected wave applied to the touch element;
A measurement scanning step that is performed in parallel with the pressing step and the calibration measurement step, and scans the irradiation position of the ultrasonic beam within the rolling surface;
And a reference position calibration step of calibrating a reference position for irradiation of the ultrasonic beam based on the measurement result of the intensity of the reflected wave. The rolling surface has a cylindrical surface shape,
The pressing surface of the calibration jig includes a cylindrical surface having a smaller radius of curvature than the rolling surface, and the calibration recess is formed in the cylindrical surface. Item 2. The load measuring method according to Item 1. The calibration jig has an outer cylindrical shape,
The end face of the calibration jig is provided with a mark for indicating the position of the calibration recess in order to align the calibration jig in the circumferential direction. Item 3. The load measuring method according to Item 1 or 2.   4. The calibration recess according to claim 1, wherein a plurality of the calibration recesses are provided, and the plurality of calibration recesses are arranged at equal intervals and in a lattice shape. 5. The load measurement method described.

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