JP2002031509A - Chamfering size measuring method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chamfering size measuring method and a device for the same capable of measuring a chamfering size of a chamfering part at a high speed with high accuracy with a simple structure. SOLUTION: This measuring device optically measures the chamfering size of the chamfering part formed on an end part of a measured material W, illuminates the chamfering part without illuminating an end face on which the chamfering part is formed, picks up an image of the illuminated chamfering part, and calculates a chamfering dimension L of the chamfering part on the basis of the image pick-up data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for measuring chamfer dimensions. More specifically, the present invention relates to a chamfer dimension measuring method and a measuring apparatus for measuring a chamfer dimension of a chamfered portion of a material to be measured in a non-contact manner using an optical sensor such as a CCD line sensor.

[0002]

2. Description of the Related Art Conventionally, in a chamfer dimension measurement for measuring a chamfer dimension of a chamfered portion formed at an end portion of a square material, a round material, or the like, visual measurement or measurement using a laser type distance meter is performed. In the measurement using a laser distance meter, for example, a laser beam is irradiated to a measurement site through a slit, a distance to each measurement point is calculated by triangulation, a coordinate position of each measurement point is plotted, and a chamfered portion is formed. A method of grasping a shape and estimating a chamfer dimension of a chamfered portion has been performed.

However, the measurement by the laser type distance meter is to pick up the diffused light due to the irregular reflection of the laser at each measuring point by the light receiving unit and calculate the distance to each measuring point, so that the measured part is a mirror surface. In some cases, the laser may be totally reflected at the measurement point and diffused light may not return to the light-receiving part. At that time, the distance to each measurement point cannot be measured accurately, and the chamfer dimension cannot be measured. There is.

In the measurement with a laser range finder, when estimating the chamfer dimension of a chamfered portion, as shown in FIG.
For example, the intersection M between the extension L1 of the one end face 101 and the extension L2 of the side face 102 of the cylindrical material 100 to be measured, and the side face 1
The dimension of the chamfered portion 103 is measured by calculating a distance MN from the actual end point N of the target 02. However, when the end face 101 has irregularities 104, the erroneous extension L3
This causes an error in the calculation result of the dimension of the chamfered portion 103, and there is a problem that the chamfered dimension of the chamfered portion cannot be measured accurately.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and has a simple configuration and a method for measuring a chamfered dimension of a chamfered portion with high speed and high accuracy. And a measuring device.

[0006]

A chamfer dimension measuring method according to the present invention is a chamfer dimension measuring method for optically measuring a chamfer dimension of a chamfered portion formed at an end of a material to be measured.
The chamfered portion is illuminated so as not to illuminate the end face on which it is formed, the illuminated chamfered portion is imaged, and the chamfered dimension of the chamfered portion is calculated based on the imaged data. I do.

In the method for measuring a chamfer dimension according to the present invention,
It is preferable to measure the chamfer dimension of the chamfered part while rotating the material to be measured around its axis.

In the method for measuring a chamfer dimension according to the present invention, when the measured chamfer dimension exceeds the first reference value, it may be determined that burrs are generated, and the measured chamfer dimension is determined. If the value is less than the second reference value, it may be determined that the chamfered portion has a flaw.

Further, in the chamfer dimension measuring method according to the present invention, it is preferable that the displacement of the material to be measured from a reference position is measured, and the chamfer dimension is corrected based on the measured value.

On the other hand, a chamfer dimension measuring apparatus according to the present invention is a chamfer dimension measuring apparatus for optically measuring a chamfer dimension of a chamfer formed at an end of a material to be measured. An illuminating unit arranged so as not to illuminate the end face, an imaging unit for imaging the chamfer illuminated by the illuminating unit, and a chamfer dimension of the chamfer based on imaging data from the imaging unit. And an image processing operation unit that calculates

In the chamfer dimension measuring device of the present invention,
Preferably, a rotation mechanism for rotating the material to be measured about its axis is provided.

Further, the chamfer dimension measuring apparatus according to the present invention includes a displacement meter for measuring a displacement of the material to be measured from a reference position, and the image processing operation section corrects the chamfer dimension based on the measured value. More preferably, it is done.

Here, the displacement meter is, for example, a laser displacement meter.

[0014]

Since the present invention is constructed as described above, the image data of the chamfered portion can be obtained by simple image processing. Can be measured. In addition, since image processing and subsequent arithmetic processing can be performed at high speed,
Measurement of chamfer dimensions can be performed at high speed.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments with reference to the accompanying drawings, but the present invention is not limited to only such embodiments.

First Embodiment FIG. 1 shows a schematic configuration of a chamfer dimension measuring apparatus for optically measuring a chamfer dimension of a chamfered portion according to a first embodiment of the present invention.

The measuring apparatus 10 includes a chamfered portion S formed at a corner portion of a round material or a square material (hereinafter, referred to as a material to be measured) W.
The illumination unit 20 that illuminates the chamfered portion S, the imaging unit 30 that captures the chamfered portion S illuminated by the illumination unit 20, and the chamfered portion S that is imaged by the imaging unit 30 And an image processing operation unit 40 for performing predetermined image processing and arithmetic processing on the image data of (1) and calculating a chamfer dimension L (see FIG. 2) of the chamfered portion S.

FIG. 2 shows a main configuration of the measuring apparatus 10.

As shown in FIG. 2, a chamfered portion S having a predetermined dimension L is provided at an intersection of one end face F and a side face G of a workpiece W made of, for example, a cylindrical steel material. Here, the dimension L of the chamfered portion S is defined as the width of the projection surface S ′ when the chamfered portion S is viewed from a direction parallel to the central axis P of the workpiece W.

The illuminating section 20 is arranged such that the optical axis 21 forms a predetermined angle θ ₁ with the one end face F so as to illuminate the chamfered section S and not to illuminate the one end face F.

The imaging unit 30 includes an optical lens 31 and a CCD.
A predetermined position Q which is constituted by the line sensor 32 and which can image the chamfered portion S illuminated by the illuminating portion 20 with an optical axis substantially parallel to the central axis P of the workpiece W and does not receive reflected light from the side surface G. Distributed to.

The optical lens 31 forms an image of the chamfered portion S illuminated by the illumination unit 20 on the CCD line sensor 32.

The CCD line sensor 32 includes an optical lens 3
1 converts the image of the chamfered portion S formed into an image data and outputs the image data. That is, the CCD line sensor 32 is a sensor in which light receiving elements (not shown) are linearly and one-dimensionally arranged, and each light receiving element accumulates charges corresponding to the amount of received light. The accumulated charges are simultaneously transferred from each light receiving element to a CCD register (not shown) at a predetermined period (for example, 100 MHz), sequentially transferred in the CCD register, and output to the outside.

The image processing operation section 40 converts the output signal (image data) of the CCD line sensor 32 into an image formed by the optical lens 31 by, for example, binarizing the output signal into a low luminance portion and a high luminance portion. Then, a threshold value process is performed on the binarized image data to perform a calculation process of calculating the dimension L of the chamfered portion S.

That is, by performing binarization processing, CC
As shown in FIG. 3, the output signal waveform of the D-line sensor 32 includes a high-luminance portion S ₁ which is a region corresponding to the chamfered portion S.
When a first low brightness portion S ₂ is an area corresponding to the area outside the measured material W, and the second low brightness portion S ₃ is a region corresponding to one end face F is formed. Therefore, set the threshold value V _r in order to extract the high brightness portion S ₁ from the output signal of the CCD line sensor 32, then corresponds to the region where the output signal value V of the CCD line sensor 32 exceeds the threshold value V _r by calculating the number of light receiving elements, it is possible to calculate a high brightness portion S ₁ of length, i.e. the dimension L'image by the optical lens 31 of the chamfered portion S. Then, by converting this dimension L 'into an actual dimension using the magnification of the optical lens 31, the chamfer dimension L of the chamfered portion S can be calculated.

As described above, the chamfer dimension measuring apparatus 10 according to the present embodiment is arranged such that the illuminating section 20 illuminates the chamfered section S and does not illuminate the one end face F. Since the portion 30 is disposed so as to receive the reflected light from the chamfered portion S and not to receive the reflected light from the side surface G, the output signal of the CCD line sensor 32 corresponds to the chamfered size L of the chamfered portion S. The high-luminance portion S1 clearly appears, which makes it possible to precisely measure the chamfer dimension L of the chamfered portion S using an inexpensive and simple CCD line sensor.

Further, a rotation mechanism (not shown) for rotating the material to be measured W about the central axis P as a rotation center is added to the measuring apparatus 10 of the first embodiment, and the material to be measured W
By continuously measuring the chamfer dimension L while rotating, the eccentricity of the chamfer can be measured quickly and accurately.

That is, the round material is chamfered by polishing each material with a grinder or the like while rotating each material around its axis. Therefore, when the center of rotation for rotating each material is eccentric, the chamfer dimension differs at each position.

However, according to the measuring device 10, since the measurement of the chamfer dimension can be performed in synchronization with the signal capturing cycle (for example, 100 MHz) of the CCD line sensor 32, the workpiece W is rotated by the rotating mechanism. Even when rotated at high speed, the chamfer dimension at each position on the circumference can be measured finely, thereby making chamfering in a much shorter time compared to a measuring method using a laser rangefinder that performs mechanical scanning, for example. Eccentricity can be detected.

In the first embodiment, the imaging section 30 is arranged in the axial direction of the workpiece W. However, the present invention is not limited to this, and it is also possible to arrange the imaging section 30 on the side of the workpiece W. is there.
In this case, the illuminating section 20 is arranged so as to illuminate the chamfered section S and not to illuminate the side face G, and the imaging section 30 receives the reflected light from the chamfered section S and receives the reflected light from the one end face F. By arranging it so as not to be performed, it becomes possible to measure the chamfered dimension as in the first embodiment.

Second Embodiment A chamfer dimension measuring apparatus according to a second embodiment is different from the chamfer dimension measuring apparatus according to the first embodiment in that the processing performed by the image processing operation unit 40 is the same as the first embodiment.
Since the configuration and the arrangement of each component are the same, a description will be given with reference to FIGS. 1 and 2.

The image processing operation unit 40 of the measuring apparatus 10 according to the second embodiment includes a chamfering unit S as in the first embodiment.
The chamfer dimension is measured, and performs the processing for judging whether there is a burr or scratches on the chamfered portion S of each measured workpiece W by the measurement L _c.

That is, as shown in FIG. 4A, when there is a burr C in the chamfered portion S of the workpiece W, FIG.
As shown in (b), the width L ₄ of the high-luminance portion S ₄ in the output signal waveform of the CCD line sensor 32 is longer than the width L ₅ of the chamfered portion S of the reference material W to be measured. It increases by the amount corresponding to the size.

Therefore, the measurement result L _{c of the} measuring device 10
Is compared with an appropriate threshold value (first reference value) L _R1 for detecting burr, and whether or not burr is generated is determined based on whether or not the measurement result L _c is equal to or more than the first reference value L _R1. It becomes possible.

The measurement result _Lc may be an average value or a median value of the dimension L continuously measured while rotating the workpiece W about the central axis P as a rotation center.

As shown in FIG. 5 (a), when a flaw D occurs in the chamfered portion S of the workpiece W, as shown in FIG. signal waveform flaw corresponding portion S ₅ becomes low luminance. Therefore,
If there is a flaw D, the length (L ₆ + L ₇ ) of the high-luminance portion is shorter than the reference length L ₅ , so that the measurement result L _c is an appropriate threshold for flaw detection (the second reference value). ) it is possible to determine whether there is a flaw D depending on whether it is less than L _R2.

[0037] In this case, the measurement results while rotating the center axis P as the center of rotation to be measured material W as L _c, can be used an average or median of continuously measured dimensions L.

Third Embodiment FIG. 6 shows a schematic configuration of a chamfer dimension measuring apparatus according to a third embodiment of the present invention, and FIG. This measuring device 10A is obtained by modifying the measuring device 10 of the first embodiment as shown in FIGS. Specifically, the displacement meter 50 is located at a position facing one end face F of the workpiece W.
Is provided, and the image processing operation unit 40 is configured as an image processing operation unit 40A so that processing based on the output signal of the displacement meter 50 can be performed.

The displacement meter 50 is for measuring the displacement of the one end face F of the workpiece W from the reference position, and is, for example, a laser displacement meter.

The image processing arithmetic section 40A calculates the displacement of the one end face F from the reference position from the output signal of the displacement meter 50, and corrects the dimension L of the chamfered section S based on the calculation result. That is, the image processing operation unit 40 of the first embodiment
Is in one end face F is the reference position Ox, as shown in FIG. 8 (a), i.e. the dimensions of the image on the assumption that the distance between the center and one end face F of the optical lens 31 is x ₁ L' Since the chamfer dimension L is calculated from the equation (1), when the one end face F is shifted from the reference position Ox as shown in FIG. 8B, a calculation error occurs.

In order to eliminate such a calculation error, the image processing calculation unit 40A calculates the displacement dx of the one end face F from the reference position Ox from the output signal of the displacement meter 50, and utilizes this displacement dx to perform the optical chamfer dimension L after the distance between the center and the end surface F of the lens 31 has been corrected from x ₁ to x ₁ + dx
Is calculated. Here, dx is positive in the direction in which the workpiece W moves away from the displacement meter 50.

As described above, according to the third embodiment, the chamfer dimension L is calculated after correcting the distance between the center of the optical lens 31 and the one end face F based on the output signal of the displacement meter 50. Therefore, even when the workpiece W is displaced from the reference position, the dimension L of the chamfered portion S can be measured with high accuracy without causing a calculation error. Embodiment 3
Other configurations and effects are the same as those of the first embodiment.

In the third embodiment, the displacement of the workpiece W from the reference position is measured by the displacement meter 50 disposed at a position facing the one end face F. However, the present invention is not limited to this. A CCD line sensor is arranged at a predetermined lateral position, that is, a position where a portion illuminated by the illumination unit 20 of the chamfered portion S can be imaged, and a displacement of the workpiece W from a reference position is calculated from the captured image. You may.

As described above, the present invention has been described based on the embodiments. However, the present invention is not limited to only such embodiments, and various modifications can be made.

For example, in the present embodiment, the material to be measured W is a round material, but the material to be measured W is not limited to a round material, but may be of various shapes. Can also. In the present embodiment,
Although the part that performs image processing and the part that performs arithmetic processing are integrated, the image processing unit and the arithmetic processing unit may be provided separately.

[0046]

As described in detail above, according to the present invention,
Because only the chamfer can be imaged, image processing is simplified,
Thereby, an excellent effect that the chamfer dimension of the chamfer can be measured with high accuracy and at high speed can be obtained.

Further, according to the preferred embodiment of the present invention, there is obtained an excellent effect that the burrs and flaws in the chamfered portion can be detected simultaneously with the measurement of the chamfered size of the chamfered portion.

Further, according to another preferred embodiment of the present invention, there is obtained an excellent effect that the chamfer dimension can be measured with high precision without causing a calculation error even when the material to be measured is shifted from the reference position. .

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a chamfer dimension measuring device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a main part of the chamfer dimension measuring device.

FIG. 3 is a schematic diagram showing an example of an output waveform of a CCD line sensor in the chamfer dimension measuring device.

4A and 4B are schematic diagrams illustrating the principle of burr detection, wherein FIG. 4A shows a material to be measured in which burr has occurred, and FIG. 4B shows an output waveform of a CCD line sensor at this time.

5A and 5B are schematic diagrams illustrating the principle of flaw detection, wherein FIG. 5A shows a material to be measured having a flaw, and FIG. 5B shows an output waveform of a CCD line sensor at this time.

FIG. 6 is a block diagram illustrating a schematic configuration of a chamfer dimension measuring device according to a third embodiment of the present invention.

FIG. 7 is a schematic diagram showing a configuration of a main part of the chamfer dimension measuring device.

8A and 8B are diagrams illustrating that a calculation error occurs when the measured material is shifted from the reference position, wherein FIG. 8A illustrates a case where the measured material is at the reference position, and FIG. This shows a case where the material to be measured is shifted from the reference position.

FIG. 9 is an explanatory diagram explaining that a measurement error occurs when the chamfer dimension of the chamfered portion is measured by the laser type distance meter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Measuring apparatus 20 Illumination part 30 Imaging part 31 Optical lens 32 CCD line sensor 40 Image processing calculation part 50 Displacement meter W Material to be measured S Chamfered part F One end face G Side surface P Central axis

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA22 AA30 AA49 BB06 CC15 DD03 FF04 FF42 FF61 GG01 HH02 HH12 JJ02 JJ08 JJ25 MM04 PP13 QQ08 QQ32 QQ42

Claims (9)

[Claims] 1. A chamfer dimension measuring method for optically measuring a chamfer dimension of a chamfer formed at an end of a material to be measured, wherein the chamfer is configured not to illuminate an end face on which the chamfer is formed. A method for measuring the chamfered dimension of the chamfered part based on the imaged data. 2. The method of measuring a chamfered dimension according to claim 1, wherein the chamfered dimension of the chamfered portion is measured while rotating the material to be measured about an axis thereof. 3. The method for measuring a chamfered dimension according to claim 1, wherein when the measured chamfered dimension exceeds a first reference value, burrs are generated. 4. The method for measuring a chamfered dimension according to claim 1, wherein if the measured chamfered dimension is less than the second reference value, a flaw is generated in the chamfered portion. 5. The method for measuring a chamfered dimension according to claim 1, wherein the displacement of the measured material from a reference position is measured, and the chamfered dimension is corrected based on the measured value. 6. A chamfer dimension measuring device for optically measuring a chamfer dimension of a chamfer formed at an end of a material to be measured, wherein the chamfer is configured not to illuminate an end face on which the chamfer is formed. An illumination unit arranged, an imaging unit that captures an image of the chamfer illuminated by the illumination unit, and an image processing operation unit that calculates a chamfer dimension of the chamfer based on imaging data from the imaging unit. A chamfer dimension measuring device, comprising: 7. A rotating mechanism for rotating a material to be measured about its axis is provided.
The chamfer dimension measuring device described. 8. The apparatus according to claim 6, further comprising: a displacement meter for measuring a displacement of the material to be measured from a reference position, wherein the image processing calculation unit corrects a chamfer dimension based on the measured value. The chamfer dimension measuring device described. 9. The chamfer dimension measuring device according to claim 8, wherein the displacement meter is a laser displacement meter.