JPH0875420A - Disk size measuring device for automobile wheel - Google Patents

Abstract

PURPOSE: To provide a device capable of measuring disk dimensions automatically. CONSTITUTION: A disk 1 is clamped to a rotating table 10, a bolt hole is measured with a CCD camera 31 and an image processing device 60. The rotating table 10 is rotated so that the bolt hole is located under a nut seat measuring element 41 rotated by 180 deg. from the CCD camera 31, the nut seat measuring element 41 is fallen into a nut seat, and the nut seat is measured. Also, sampling data is fed to a computer 70 where the pitch of the bolt hole and nut seat, and others are calculated. Thus various work dimensions can be measured automatically by merely setting a work 1 once on the rotating table 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk dimension measuring device capable of measuring all dimensions of a wheel of an automobile wheel with respect to bolt holes, nut seats, and dishing by setting the disk to be measured only once on a table. .

[0002]

2. Description of the Related Art Conventionally, disk bolt holes, nut seats,
The dimensions of the dishing were measured in separate steps, and therefore by changing the settings, using hand-measuring instruments such as calipers, calipers, dial gauges, etc.

[0003]

However, the prior art has the following problems. Since it is manual work, it is inefficient, the measured values vary from person to person, and skill is required for measurement. Since the setting changes depending on the measurement of each part of one disk, the reference value changes each time, and the measurement accuracy decreases. An object of the present invention is to provide a disk size measuring device for an automobile wheel, which can automate disk measurement and can measure each part by setting the disk once.

[0004]

The device of the present invention for achieving the above object is as follows. A rotary table rotatable about the Z-axis; and a measuring unit capable of advancing and retracting in the Z-axis direction with respect to the rotary table, the measuring unit including a CCD camera device, a nut seat measuring device, and a dishing measuring device.
The CCD camera device comprises a CCD camera and the C
An XY table that movably supports the CD camera in the X-axis and Y-axis directions, and the nut seat measuring device includes an X-axis, a Y-axis, and a Z-axis.
A nut seat measuring element that is supported in a floating manner in the axial direction and three linear gauge sensors that detect the amount of movement of the nut seat measuring element in the X-axis, Y-axis, and Z-axis directions. A disk dimension measuring device for an automobile wheel, comprising an axially movable dishing probe and a linear gauge sensor for detecting the amount of movement of the dishing probe in the Z-axis direction.

[0005]

The disk is set and fixed on the rotary table so that the bolt holes are within the field of view of the CCD camera. At this point, the center of the hub hole of the disk and the center of the rotary table are aligned. Bring the measuring unit close to the disk and find the deviation angle α between the center of the CCD camera and the center of the bolt hole.
The rotating table is rotated to 20 ° + α, and the dishing data is sampled. The distance from the center of the rotary table of the dishing probe is changed on the first and second rounds. Next, the bolt hole is actually measured, the hole diameter of the bolt hole,
The image of the central coordinate CCD camera is obtained by image processing. Then rotate the rotary table 180 ° (C
Since the CD camera and the nut seat measuring element are facing each other across the center of the rotary table), the nut seat measuring element is applied to the nut seat, and the diameter and center coordinates of the nut seat are calculated.
Next, the rotary table is rotated to measure the next bolt hole, and the rotary table is rotated 180 ° to measure the nut seat for all the bolt holes. After measuring all bolt holes, raise the measuring unit, remove the disc from the rotary table, and
Finish cycle measurement. In the above measurement, the measurement is automated, and the bolt hole, the nut seat, and the dishing can be measured by setting the disc on the rotary table only once without resetting.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 6-8 show the disk and dimensions of an automobile wheel. The automobile wheel comprises a welded joint of a disc 1 and an annular rim. The rim and the disc are separately formed, and the disc is fitted into the rim and welded. The disk 1 has a bolt hole 2 through which a 6-hole or 8-hole hub bolt penetrates, a nut seat 3 formed of a partial spherical surface around each bolt hole, and further has a decorative hole 4. The hub portion of the disc 1 is provided with dishing (curved in a dish shape) in order to apply an elastic force to the hub nut in order to prevent the hub nut screwed into the hub bolt from loosening. The dimensions of the disk 1 to be measured are shown in FIG. 6, the facing pitch p1 (pitch between opposite bolt holes),
Adjacent pitch p2 (pitch between adjacent bolt holes), eccentricity (deviation between bolt hole pitch circle circle and hub hole center),
Dishing Y shown in FIG. 7, nut seat diameter K shown in FIG.
The diameter of the bolt hole, the center of the bolt hole (I, J), the plate-side (deviation between the center of the nut seat and the center of the bolt hole), and the like.

As shown in FIG. 1, a disk dimension measuring device for an automobile wheel according to an embodiment of the present invention for measuring the above-mentioned disk has a rotary table 10 and a measuring unit 20.
And the measurement unit 20 includes the CCD camera device 3
0, a nut seat measuring device 40, and a dishing measuring device 50. The disk size measuring device further includes an image processing device 60 and a computer 70.

The rotary table 10 is a table which is rotatable about the Z axis and is driven by a mechanical torque motor 11 to mount a disk 1 which is a work. The disk 1 is fixed by a collet chuck 12 with the center aligned with the table. It The measurement unit 20 is supported by a movable frame 22 that moves up and down with respect to a fixed frame 21, and is lifted and lowered by an air cylinder 23 for lifting the measurement unit. C
The CD camera device 30 has a CCD camera 31. CC
The D camera 30 has X, Y attached to the movable frame 22.
A disc 1 mounted on an XY table 24 movable in the axial direction, extending downward, and fixed to a rotary table 10.
Take a picture near the bolt hole. The image of the CCD camera 31 is sent to the image processing device 60, subjected to image processing, and displayed on the display.

The nut seat measuring device 40 is disposed on the movable support frame 22 at a position facing the CCD camera 31 with respect to the center line of the rotary table, that is, above the position obtained by rotating the rotary table by 180 °. It is supported. Further, a dishing measuring device 50 is arranged at a position of 90 ° from the CCD camera 31 around the center of the turntable, and is supported by the movable support frame 22. The nut seat measuring device 40 and the dishing measuring device 50 are arranged in the X-axis direction with respect to the movable support frame 22 in the guide bar 2
5 is movably supported and can move in the radial direction of the disc above the disc 1.

As shown in FIG. 2, the nut seat measuring device 40 includes a nut seat measuring element 41 which is floatingly supported in the X-axis, Y-axis and Z-axis directions, and a floating support bearing 4 in the X-axis direction and the Y-axis direction.
2, a Z-axis direction floating support bearing 43, an X-axis direction linear gauge sensor 44, a Y-axis direction linear gauge sensor 45, a Z-axis direction linear gauge sensor 46, and a gauge head elevating / lowering a nut seat gauge head 41. And an air cylinder 47 for use. Linear gauge sensor 44, 4
The resolution of 5,46 is 0.001 mm. Even if the nut seat gauge 41 and the nut seat of the disk 1 are displaced in the X and Y axis directions, as long as the floating support bearing 42 is within the displacement absorption allowable range (for example, 1.5 mm), the nut seat gauge 41 is The position is automatically adjusted to the disc nut seat,
Can be seated on the nut seat. Linear gauge sensor 44, 4
The outputs of 5, 46 are input to the computer 70.

As shown in FIG. 3, the dishing measuring device 50 includes a dishing probe 51 which is movable in the Z-axis direction,
It has a Z-axis direction movable support bearing 52 and a Z-axis direction linear gauge sensor 53. Dishing probe 51
As shown in FIG. 4, the position in the Z-axis direction is measured at two points A and B having different positions in the disk radial direction. In the dishing measurement, the disk is rotated twice around the Z axis,
One of the points A and B is measured at the first time and the other is measured at the second time. The linear gauge sensor 53 measures 256 points per revolution and sends the sampling data to the computer 70. The dishing angle θ is obtained from θ = tan− ¹ (h ₂ −h ₁ ) / a. However, h ₂ −h ₁ is the position difference in the Z direction at points A and B, and a is the distance between points A and B.

In FIG. 4, the output value z in the Z-axis direction at the nut seat center of the linear gauge sensor 46 of the nut seat measuring device 40 and the output value h _{2 at the} points A and B of the linear gauge sensor 53 of the dishing measuring device 50. , H ₁ , the distance h between the disk surface and the center of the sphere of the nut seat measuring element 41 (having a radius of 22 mm, for example) is obtained from the following equation. h = {z− (h ₂ + h ₁ ) / 2} cos θ Further, the nut seat diameter K is obtained from the following equation. K = 2 (22 ² −h ² ) ^1/2

The center of the nut seat can be measured as shown in FIG. Here, the center of the nut seat means a point through which a perpendicular line passing through the ball center when the R22 ball gauge is set on the nut seat. First, the computer 70 stores the coordinates (a, 0) of the reference point from the center of the rotary table, with the center of the nut seat measuring element 41 when the nut seat measuring element 41 does not hit the nut seat as the reference point. Next, the amount of deviation (X, Y) of the center of the nut seat gauge 41 from the reference point when the nut seat gauge 41 is dropped into the nut seat is measured by the linear gauge sensors 44 and 45. Next, the center of the nut seat is determined as (a + X, 0-Y). .

When the diameter K of the nut seat and the center of the nut seat are obtained, the rotary table 10 is rotated by pitches for measurement, whereby the adjacent pitch P ₁ of the nut seats, the facing pitch P ₂ , and the pitch circle eccentricity are measured. P ₃ is obtained. These are obtained by computing the measurement result by the nut seat gauge 41 by the computer 70. On the other hand, the measurement and calculation of the bolt hole diameters (I, J), the adjacent pitch P ₁ , the facing pitch P ₂ , and the pitch circle eccentricity P ₃ are C
This is performed by the CD camera device 30, the image processing device 60, and the computer 70. For example, a bolt hole moves the scan line in the vertical direction on the screen while scanning the screen in the image processing device 60 of the disk imaged by the CCD camera 31 with the horizontal scan line, and the image of the bolt hole on the screen and the other place. From the difference in the brightness from the above, the point where the scan line crosses the peripheral edge of the bolt hole image is detected, the point around the bolt hole circle is detected from each scan line, and the bolt hole circle is obtained by the least square method from the result. Once the circle is obtained, its center can be easily calculated by the computer 70. Do this for all bolt holes. When the nut seat and the bolt hole are measured, the plate-side deviation, which is the eccentricity between the center of the nut seat and the center of the bolt hole, can be easily calculated by the computer 70.

Next, the operation will be described. First, the origin of the measuring device is adjusted. Before performing the actual measurement, the position of each central position of the image processing device 60, the CCD camera 31, the nut seat measuring element 41, and the dishing measuring element 51 is measured with respect to the center of the rotary table, stored in the computer 70, and measured in the actual measurement. Use each reference point. Next, the actual measurement of the disk to be measured is performed. In the first step, the work as the disk 1 is set and clamped on the rotary table 10 so that the bolt holes can be seen in the field of view of the CCD camera. In the second step, the automatic operation mode is selected by the keyboard input of the computer 70, and the number of bolt holes (6 or 8) of the workpiece to be measured is selected. In the third step, the workpiece 1 is collet chuck 1
Fix it to the turntable 10 by 2, and press the start button. In the fourth step, the movable frame 22 of the measuring unit 20 is moved toward the rotary table 10 by the air cylinder 23 for raising and lowering the measuring unit, and the CCD camera 31 and the image processing device 60 coarsely position the bolt holes by a computer command. I do.

In the fifth step, the deviation angle between the CCD camera visual field center and the bolt hole center is calculated by the computer 70, the rotary table 10 is rotated by the deviation angle, and the visual field center and the bolt hole center are aligned on the screen. Then, the rotary table is rotated twice, 720 °, and at points A and B in FIG.
The dishing data of 256 points per round is sampled. In computer 70, it is determined whether the measured dishing is within a predetermined dishing value. If not, an alarm is issued and an NG signal is issued. In the sixth step, the bolt holes that have been roughly measured previously are actually measured by the CCD camera 31 and the image processing device 60, and the bolt hole diameter and the bolt hole center coordinate data are output and received by the computer 70 and temporarily stored. Seventh
In the process, after measuring the bolt holes, turn the rotary table 10 180 °
Rotate the nut seat of the hole that has been measured for the bolt hole to C
It is brought under the nut seat measuring element 41 which is located 180 ° opposite to the CD camera 31. The nut seat gauge head 41 is lowered by the air cylinder 47 for lifting the gauge head and dropped into the nut seat.
Is sent to the computer 70, and the computer 70 calculates the nut seat diameter and the nut seat center coordinates. with this,
Measurement of one bolt hole and nut seat is completed.

In the eighth step, the work 1 is placed on the rotary table 10.
Then, it is rotated by (180 + 360 / number of holes) degrees, the next bolt hole is measured in the image, and the nut seat of the hole is measured by the nut seat gauge 41 by rotating 180 °. In the ninth step, the operation of the eighth step is repeated for the number of bolt holes. After measuring all bolt holes and all nut seats, the bolt hole, nut seat facing pitch, side-by-side pitch, and plate offset are calculated and displayed on the display. If a defective product that exceeds the limit is detected, it is displayed and an alarm is issued. In the tenth step, the measuring unit 20 is raised and the work 1 is removed from the rotary table 10 by the collet chuck unclamping. This completes one cycle, and then the above is repeated using the disc.

[0018]

According to the present invention, various dimensions of the disk can be automatically measured, so that the measuring time can be shortened, no skill is required, and the pitch and the like can be calculated from data analysis and storage. Further, since the work need only be set once on the rotary table, the error in the measurement result is reduced, and the reliability of the measurement is improved.

[Brief description of drawings]

FIG. 1 is a front view of an apparatus according to an embodiment of the present invention.

2 is an enlarged cross-sectional view of the nut seat measuring device in FIG. 1. FIG.

3 is an enlarged cross-sectional view of the dishing measuring device in FIG.

FIG. 4 is an enlarged cross-sectional view in the vicinity of a nut seat showing the nut seat diameter measuring principle.

FIG. 5 is an enlarged plan view in the vicinity of a nut seat showing the principle of measuring the nut seat center.

FIG. 6 is a front view of a disc.

7 is a cross-sectional view of the disc of FIG.

FIG. 8 is an enlarged cross-sectional view near the nut seat, showing various dimensions of the nut seat.

[Explanation of symbols]

 1 Disc 2 Bolt Hole 3 Nut Seat 10 Rotating Table 20 Measuring Unit 30 CCD Camera Device 31 CCD Camera 40 Nut Seat Measuring Device 41 Nut Seat Measuring Element 50 Dishing Measuring Device 51 Dishing Measuring Element 60 Image Processing Device 70 Computer

Claims (1)

[Claims] 1. A rotary table rotatable about the Z-axis, and capable of advancing and retracting in the Z-axis direction with respect to the rotary table,
A CCD camera device, a nut seat measuring device, and a measuring unit equipped with a dishing measuring device. The CCD camera device includes a CCD camera and an XY table that movably supports the CCD camera in the X-axis and Y-axis directions. The nut seat measuring device has a nut seat measuring element floatingly supported in the X-axis, Y-axis, and Z-axis directions and the X-axis and Y-axis of the nut seat measuring element.
And a linear gauge sensor for detecting the amount of movement in the Z-axis direction. The dishing measuring device detects a dishing probe movable in the Z-axis direction and the amount of movement of the dishing probe in the Z-axis direction. A disk dimension measuring device for an automobile wheel, which has a linear gauge sensor.