JP2000292132A - Work quality inspecting method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a work quality inspecting method and apparatus which can judge precisely quality of a work such as thickness, flaw, protrusion and bend. SOLUTION: This work quality inspecting device is equipped with a first slit light source 10R casting a slit light on one surface of a work W, a first image sensing device 11R which is arranged outside an irradiation optical axis of the light source 10R and picks up a first slit image projected on the one surface of the work W, a second slit light source 10L casting a slit light on the other surface of the work W, a second image sensing device 11L which is arranged outside an irradiation optical axis of the light source 10L and picks up a second slit image projected on the other surface of the work W, and a work quality judging means 72 which judges quality of the work on the basis of compared results. The results are obtained by comparing the first slit image data and the second slit image data outputted from the first image sensing device 11R and the second image sensing device 11L, respectively, with first standard slit image data and second standard slit image data obtained by irradiating and sensing both surfaces of a known quality standard work with the first light source 10R and the first sensing device 11R, and the second light source 10L and the second sensing device 11L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting the quality of a work by using a so-called light sectioning method, which takes a slit image projected on the work and performs image processing.

[0002]

2. Description of the Related Art In the production of sintered magnets, generally, a rod-shaped sintered body is obtained by pressing a magnet raw material and then sintering the formed body. By the way, since a compact shrinks by sintering, a rod-shaped sintered body is sliced by an outer peripheral blade or a wire to obtain a plate-shaped semi-finished product having a specified thickness. Thereafter, the surface of the plate-like semi-finished product is polished to obtain a magnet product. However, when the rod-shaped sintered body is cut as described above, a part of the tapered plate-shaped semi-finished product that does not have a sufficient thickness, and a part of the plate-shaped semi-finished product that has a step-like flaw that is greatly dented in the thickness direction. A plate-shaped semi-finished product having a so-called saw mark may be produced in which a cut surface is significantly roughened due to blurring of a product or a wire.

Therefore, a plate-shaped semi-finished product (work) of a sintered magnet is used.
With regard to, for example, it was examined to inspect the quality such as thickness, scratches, protrusion, curve, and saw mark by a conventionally known inspection method using slit light. As an inspection method using such slit light, for example, JP-A-10-2321
A work inspection method by a light cutting method disclosed in Japanese Patent Application Laid-Open No. 10-210 is cited. The work inspection method is configured to detect the edge position of the work based on slit image data obtained by irradiating one side of the work with slit light and imaging the work. It is also possible to measure such as. That is, a standard work with a known thickness is tested to capture a standard slit image on one side, and a virtual reference plane serving as a reference plane at the time of thickness measurement calculation is determined in advance based on the standard slit image data. When measuring the thickness of the inspection work, a slit image is projected by irradiating one side of the inspection work with slit light, and image data of the slit image is compared with image data of the virtual reference plane. Thus, the thickness of the inspection work is calculated.

[0004]

In the above-described conventional work inspection method, the thickness of the work is calculated by regarding the other side, which is not irradiated with the slit light, as a flat virtual reference plane. The surface is not always flat, or the other surface is inclined and the thickness may not be uniform. Therefore, there has been a problem that the measurement accuracy of the work quality is low.

The present invention has been made in view of the above-described conventional problems, and is a work quality inspection capable of accurately determining the quality of a work such as a thickness, a scratch, a protrusion, a saw mark, or a curve. It is intended to provide a method and apparatus.

[0006]

In order to achieve the above object, a work quality inspection method according to the present invention irradiates a slit light to a work, and irradiates both surfaces of the work at the same position with the slit light irradiation optical axis. The quality of the work is determined based on the slit image data on both surfaces of the work at the same position obtained by the image pickup device arranged at the same position and obtained by the image pickup device.

[0007] Alternatively, the work is irradiated with slit light, and both surfaces of the work at the same position are imaged by an image pickup device arranged outside the irradiation light axis of the slit light, and the work at the same position obtained by imaging by the image pickup device is obtained. Each slit image data on both sides is compared with each standard slit image data on both sides of the standard work at the same position obtained by imaging the standard slit images projected on both sides of the standard work of known quality by the image pickup device. This is a method of determining the quality of a work based on a result.

In each of the above methods, the work is moved to the slit light irradiation position, and the slit images on both surfaces of the work at the same position during the movement are synchronously picked up by the image pickup device.

Further, the quality of the work in each of the above methods is a thickness.

Further, in the above method, the work is arranged so that the thickness detecting surface is substantially in the direction of gravity, and slit light is applied to both side surfaces of the work.

The work quality inspection apparatus according to the present invention captures a slit light source for irradiating the work with slit light and a first slit image which is arranged outside the irradiation optical axis of the slit light source and projected on one surface of the work. A first imager, a second imager arranged outside the irradiation optical axis of the slit light source to capture a second slit image projected on the other surface of the work, and a first imager and a second imager, respectively. The output first slit image data and second slit image data of the work at the same position, and the first standard slit image data and second standard at the same position obtained by irradiating and imaging both surfaces of the standard work of known quality, respectively. And a work quality determining means for determining the quality of the work based on a result of comparison with the slit image data.

Further, in addition to the above-described device configuration, a work carrying means for carrying a work to a slit light irradiation position, a work carrying means for carrying a work out of the slit light irradiation position, and a work transfer by the work carrying means. A transfer speed control unit is provided for making the speed and the work transfer speed by the work unloading unit substantially the same.

In the above-described apparatus configuration, each of the work loading means and the work unloading means is constituted by a pair of belt bodies for sandwiching and transporting the work from both sides, and passing through the slit light irradiation position. In this case, the work loading means and the work unloading means simultaneously hold and transport the work.

In each of the above-described device configurations, the quality of the work is made to be a thickness.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view showing a work quality inspection apparatus according to an embodiment of the present invention, FIG. 2 is a side view of the work quality inspection apparatus, FIG. 3 is a front view of the work quality inspection apparatus, FIG. FIG. 5 is a sectional view taken along line AA in FIG. 4, showing a configuration of the drive and transport mechanism of the unloading means and the transport speed control means. In the work quality inspection apparatus 1 shown in each figure, for example, a plate-shaped bow-shaped work obtained by slicing a rod-shaped sintered body of a sintered magnet obtained by sintering after press forming with an outer peripheral blade or a wire saw is used. ,
It is used as a work W for inspection. However, the work used for the quality inspection of the present invention is not limited to the above-described arc-shaped work of the sintered magnet.

Work quality inspection apparatus 1 according to this embodiment
Has a transport path 66 for transporting a work formed on the front and rear of the apparatus main body 2 as will be described in detail later.
A first slit light source 10R represented by a semiconductor laser or the like is provided on the right side of the conveyance path 66, and a second slit light source 10L is also provided on the left side. In addition, a first imager 11R including a CCD camera or the like is provided outside the irradiation optical axis near the first slit light source 10R, and a second imager 11L is provided outside the irradiation optical axis near the second slit light source 10L. . A pulley 4 around a horizontal axis is arranged at a position above a front part of the apparatus main body 2, and a pulley 3 is arranged at a rear part. An endless belt body 5 having a horizontal conveying surface is wound around these pulleys 3 and 4. The belt body 5 includes an idle pulley 6 disposed between the pulleys 3 and 4.
8 and the drive pulley 7 allow the vehicle to travel longitudinally without slack. These pulleys 3, 4, 6, 7,
A belt driving unit 20 for placing a work is configured from the belt driving unit 8 and the belt body 5, and the transport path 66 is formed along the belt body 5 above the belt driving unit 20.

On both sides of the transport path 66 on the workpiece loading side, long loading guides 23 and 24 are provided facing each other.
The carry-in guide 23 is fixed to the apparatus main body 2. The carry-in guide 24 is variably attached to the apparatus main body 2 via the guide movable device 13, and can be moved away from the carry-in guide 23 by operating the guide width adjusting handle 14 so that the width of the transport path 66 can be adjusted. I have. Then, small-diameter rollers 27 and 34 are attached to the apparatus main body 2 near the front ends of the carry-in guides 23 and 24, and pulleys 31 and 38 are attached to the apparatus main body 2 near the pulley 3 respectively. The belt body 32 is moved from the pulley 31 to the loading guide 23.
Is wound around a small-diameter roller 27 along the inner surface thereof, and further wound around a pulley 28, a driving pulley 29, a tension pulley 30, and a pulley 31 in order to be endless. These small-diameter rollers 27, pulleys 28, 29, 30, 31,
The belt driving unit 33 </ b> R is constituted by the belt body 32.

The belt body 39 is wrapped around the small-diameter roller 34 from the pulley 38 along the inner surface of the carry-in guide 24,
The pulley 35, the drive pulley 36, the idle pulley 37, and the pulley 38 are wound around the pulley in this order to be endless.
These small diameter rollers 34, pulleys 35, 36, 37, 3
8 and the belt body 39 constitute a belt driving unit 33L. That is, the work carrying means 53 for carrying the work W from the belt driving unit 33R, the belt driving unit 33L, and the belt driving unit 20 to the slit light irradiation position 12.
Is configured.

On the other hand, carry-out guides 25 and 26 are provided facing each other on both sides of the conveyance path 66 with a measurement space serving as the slit light irradiation position 12 with respect to the carry-in guides 23 and 24. The carry-out guide 25 is fixed to the apparatus main body 2. The carry-out guide 26 is variably attached to the apparatus main body 2 via the guide movable device 15, and can be moved by operating the guide width adjusting handle 16 to adjust the width of the transport path 66.

The irradiation position 12 near the carry-out guides 25 and 26
Smaller diameter rollers 41 and 47 are attached to the closer apparatus main body 2, respectively. Pulleys 42 and 48 are respectively attached to the apparatus main body 2 near the pulley 4. The belt body 46 is wrapped around the pulley 42 along the inner surface of the carry-out guide 25 from the small-diameter roller 41, and is wrapped around the tension pulley 43, the drive pulley 44, the pulley 45, and the small-diameter roller 41 in an endless manner. The small-diameter roller 41, the pulleys 42, 43, 44, 45, and the belt body 46 constitute a belt driving unit 40 </ b> R.

The belt body 52 is wrapped around the pulley 48 along the inner surface of the carry-out guide 26 from the small-diameter roller 47, and is wrapped around the idle pulley 49, the driving pulley 50, the pulley 51, and the small-diameter roller 47 in an endless manner. . These small diameter rollers 47, pulleys 48, 49, 50, 5
1 and the belt body 52 constitute a belt driving unit 40L. In other words, the belt driving unit 40 </ b> R, the belt driving unit 40 </ b> L, and the belt driving unit 20 discharge the work W from the slit light irradiation position 12.
4 are configured. A downstream side of the work discharge means 54 in the transport direction is a discharge path 55.

The work carrying means 53 sandwiches the work W whose thickness detecting surfaces (both sides) are directed in the direction of gravity between a pair of belt bodies 32 and 39 having their respective conveying surfaces vertical. (See FIG. 5).
reference). Although not shown, the work unloading means 54 is also a pair of belt bodies 46 and 52 having their transport surfaces vertical.
The work W is conveyed while nipping the work W from both left and right sides. Further, the work carrying means 53 and the work carrying means 5
The space length between the four is set shorter than the dimension of the workpiece W in the transport direction, so that the workpiece W is reliably transferred from the workpiece loading means 53 to the workpiece unloading means 54. Further, by using the small-diameter rollers 27, 34, 41, and 47 as the rollers arranged near the irradiation position 12 as described above, the measurement space can be widened, and the degree of freedom of arrangement of the image pickup device and the slit light source can be increased. growing.

The pulley 62 provided coaxially with the drive shaft of the drive pulley 29, the pulley 63 provided with the drive shaft of the drive pulley 36, the pulley 64, the pulley 57, and the drive shaft of the drive pulley 44 are provided coaxially. Provided pulley 58,
Pulley 5 provided coaxially with the drive shaft of drive pulley 50
9, an endless timing belt 65 is wound around the pulley 60 and the pulley 61 in this order. That is, each pulley 62, 63, 64, 57, 58, 59, 6
0, 61, and the timing belt 65, the work transfer speed by the work loading means 53 and the work unloading means 54.
Transport speed control means 56 for making the workpiece transport speed substantially the same as that of the workpiece transport speed.

Work detection sensors 67R and 67L for detecting the arrival of the work W conveyed by the work carrying means 53 are provided on the left and right sides of the irradiation position 12, respectively. A receiving table 17 for receiving the work W carried out from the work carrying-out means 54 is provided at an upper front portion of the apparatus main body 2. A forward shooter 18 is provided below the tip of the receiving table 17.
Are arranged, and the work W from the receiving table 17 is carried forward. The forward shooter 18 is configured to be movable back and forth. Further, integral side shooters 19R and 19L protruding left and right are attached to the front surface of the apparatus main body 2 so as to be movable left and right. Side shooter 19R,
In 19L, the preceding shooter 18 moves forward and
When there is a space between the work W and the work W, the work W dropped from the receiving table 17 is carried out to the left or right.

FIG. 6 shows a control configuration of the work quality inspection apparatus 1. The slit light 68R is placed at the irradiation position 12 which is substantially perpendicular to the work W transport direction (the direction of the wide arrow).
(Irradiation optical axis), 68L (irradiation optical axis)
First slit light source 10R and second slit light source 10L
Are arranged respectively. Also, at positions where the reflected light 69R and the reflected light 69L of the optical axis inclined at an angle θ (for example, 60 degrees) from the conveyance direction of the work W with respect to the irradiation points of the slit lights 68R and 68L on both surfaces of the work W as centers, A first imager 11R and a second imager 11L are respectively arranged.

First imager 11R and second imager 11L
Each have 5 CCD elements (CCD1 to CCD5)
Are built in, and the CCD terminals R1, R2, R3, R4, R5
And CCD terminals L1, L2, L3, L4, L5. Further, a synchronization signal is given to the first image pickup device 11R and the second image pickup device 11L by an image synchronization cable 70. CCD terminals R1, R2, R
3, R4, R5 and CCD terminals L1, L2, L3, L
4, L5 are connected to the image synthesizing units M1, M2, M3, M4, M5 of the corresponding image synthesizing means 71, respectively. Further, the image synthesizing units M1, M2, M3,
M4 and M5 are connected to the corresponding image processing boards N1, N2, N3, N4 and N5 of the work quality determination means 72. A data input device 75 such as a trackball and a mouse and an external personal computer 76 are connected to the signal input side of the work quality determining means 72, and a monitor 74 and a external device such as a CRT and a liquid crystal display are connected to the signal output side. The control device 73 is connected.

Subsequently, image processing and work quality calculation processing by the work quality inspection apparatus 1 will be described in detail. Here, thickness is mainly exemplified as the quality to be inspected. However, not only the thickness but also the saw mark and the like may be detected as the quality. First, as shown in FIG. 7, the workpiece W is transported along the virtual plane 77 corresponding to the left and right central planes of the transport path 66, and the workpiece W that has reached the irradiation area 78 is provided with the first slit light source 10 </ b> R and the second slit light source 10. When the slit light from 10L is respectively irradiated, the first slit image 79R and the second slit image 79L are projected on both surfaces of the work W at the same position during traveling.

At this time, the work W is placed on the belt body 5 of the belt driving section 20 and is irradiated with the irradiation area 78 while being clamped left and right by the belt bodies 32 and 39 of the work carrying means 53.
, So that there is little misalignment between the top, bottom, left, and right during transportation. In addition, the work W has a belt body 32, 3 at its rear end.
9, the front end that has exited the irradiation area 78 is simultaneously held by the belt members 46 and 52 of the work unloading means 54, so that the light passes through the irradiation area 78 and is delivered to the work unloading means 54 smoothly. No blur occurs when the slit light is irradiated. As a result, the quality (thickness) determination accuracy described later is improved.

Next, as shown in FIGS. 8 (a) and 8 (b), the first image pickup device 11R and the second image pickup device 11L provide a work image W on the entire right surface of the work including the first slit image 79R.
An image of the workpiece image WL on the entire left face of the workpiece including the R and second slit images 79L is synchronously captured.

In this case, as shown in FIGS. 9 and 10, the workpiece W is transported at three measurement points P1, P
The thickness is measured at 2, P3. These measurement points P
Reference numerals 1, P2, and P3 indicate positions that have arrived at predetermined times (three different time points) measured by a timer from when the work detection sensors 67R and 67L detect the passage of the tip end of the work W. Then, the first slit images 79R1, 79R2, and 79R3 are imaged by the first imager 11R on the right side of the work at the measurement points P1, P2, and P3.
Although not shown, the first slit images 79R1, 79R2, 79R3 are also provided by the second imager 11L on the left side of the work.
Are taken at the corresponding positions.

Then, as shown in the flowcharts of FIGS. 11 and 12, the work image in the first photographing area 82R is transferred from the CCD terminals R1 to R5 of the first image pickup device 11R to the image synthesizing units M1 to M5 of the image synthesizing means 71. Each of them is taken into M5 (step S20a in FIG. 12). The work image in the first photographing region 82R is the first imager 1
Unit image 80R photographed by 1L CCD1 to CCD5
1 to 80R5. Unit image 80R1-80
R5 is partially overlapped so as not to generate a non-photographing part in an adjacent part of each other. Subsequently, the image combining means 7
1 is a first cutout image 8 including a first slit image 79R.
1R is cut out from the first imaging region 82R. On the other hand, the work image in the second photographing area 82L is also the second imager 11L.
Are taken into the image synthesizing units M1 to M5 of the image synthesizing means 71 from the CCD terminals L1 to L5 (step S20b). The work image in the second photographing area 82L includes unit images 80L1 to 80L5 photographed by the CCD1 to CCD5 of the second imager 11L. The image synthesizing unit 71 cuts out the second cutout image 81L including the second slit image 79L from the second photographing area 82L. Then, the image synthesizing units M1 to M5 of the image synthesizing means 71
Combines the first clipped image 81R and the second clipped image 81L, each of which has been clipped as described above, into a combined image 83 (step S21). Subsequently, the image combining units M1 to M5 output the image data relating to the combined image 83 to the image processing boards N1 to N5 of the work quality determining unit 72 for each unit image.

As shown in FIG. 13, the image processing boards N1 to N5 of the work quality judging means 72 convert the image data of each unit image relating to the first slit image 79R and the second slit image 79L by 100 in the X-axis direction. It is divided into a plurality of divided windows Cn (n is the number of divisions and can be set to an arbitrary value; in this example, n = 100). Then, the image processing boards N1 to N5 are connected to the first slit image 79R and the second slit image 79R.
With respect to the slit image 79L, a projected center-of-gravity value (Y value) is obtained from the frequency (X-axis direction frequency) of the intensity (luminance) of the received light for each divided window Cn.

Prior to the thickness inspection, teaching for a standard workpiece with a known thickness (for example, using two types of 1.5 mm and 1.6 mm) is performed in advance. In such teaching, the standard work is provided to the work quality inspection apparatus 1 to capture the first standard slit image 84R and the second standard slit image 84L, and an imager specific to each imager is obtained based on the standard slit image data. The coefficient is corrected for each CCD element, and the corrected imager coefficient K
1, K2 is the image processing board N of the work quality determination means 72
1 to N5.

Subsequently, the image processing boards N1 to N5 calculate the thickness Twn in each divided window Cn. These thicknesses Twn are calculated by the following equation (1). TWn = Tb × K2-Ta × K1 + KT (1) Ta = CP1-CT1 Tb = CP2-CT2 Here, CP1: Projected barycentric value of the first slit image obtained from the inspection work CT1: First standard slit Reference value K1 corresponding to the image K1: The imager coefficient of the first imager CP2: Projected center of gravity of the second slit image obtained from the inspection work CT2: Reference value corresponding to the second standard slit image K2: The value of the second imager Imager coefficient KT: Reference thickness.

With respect to the first slit image 79R for each unit image, the projected centroid value CP1 obtained in each divided window Cn
Is compared with a corresponding reference value CT1 (corresponding to the first standard slit image 84R in FIG. 8A) and a difference (CP1-CT
1) is obtained and set as the virtual thickness Ta (see FIG. 8A). Also, regarding the second slit image 79L, the projection center-of-gravity value CP2 obtained for each divided window Cn is converted to the corresponding reference value CT2 (the second standard slit image 84L of FIG. 8B).
The difference (CP2−CT2) is obtained by comparing with the virtual thickness Tb (see FIG. 8B). And the virtual thickness T
From the value obtained by multiplying b by the imager coefficient K2 of the second imager 11L, the virtual thickness Ta is used to calculate the imager coefficient K1 of the first imager 11R.
Is subtracted, and the reference thickness KT is further added to obtain the work W in each divided window Cn.
Is calculated.

That is, the work quality determination means 72 calculates the image data of the first slit image 79R and the image data of the second slit image 79L output from the first image pickup device 11R and the second image pickup device 11L, respectively, Both surfaces of a known standard work are connected to the first slit light source 10R,
The first imaging device 11R, the second slit light source 10L, and the first imaging device 11L obtained by irradiating and imaging each using the second imaging device 11L.
The image data of the standard slit image 84R and the image data of the second standard slit image 84L are compared, and the thickness TWn of the workpiece W is calculated based on the comparison result.

Subsequently, the image processing boards N1 to N5 output respective thickness inspection results to the external control device 73. Therefore, referring to FIG. 12 again, based on the thickness inspection results from the image processing boards N1 to N5, the external control device 73 determines whether the work W is a good product (OK: within the allowable thickness range) or a defective product (NG: NG: Thin (-) below the allowable range,
It is determined whether it is thicker (+) than the allowable range (steps S22a and S22b in FIG. 12), and the presence or absence of a flaw is also determined (steps S23a and S23b). Next, the external control device 73 operates the aforementioned shooter 18 or the side shooters 19R and 19L based on the above determination result, and outputs the determination result as data on the monitor 74 to display it (step S24). For example, if all the determination results are OK, the work W is discharged forward from the preceding shooter 18 (step S25). NG (-) and scratch NG
If there is a scratch, the shooter 18 is moved forward, and the integrated side shooters 19R and 19L are moved.
Is moved to the left, and the work W is discharged from the side shooter 19L (step S27). In the case of NG (+),
The work W is discharged from the side shooter 19R moved to the right side (step S26).

Next, a description will be given of a mode of detecting and judging scratches or protrusions (abnormal protrusions) generated on the work surface as the quality of the work W with reference to FIG. All split windows Cn
A straight line in the X-axis direction represented by the average value of the projected barycenter values obtained in the above is defined as an approximate straight line AV. Then, a difference D between the projection center of gravity value of each divided window Cn and the Y value indicated by the approximate straight line AV is obtained, and when the difference D falls below or exceeds a predetermined judgment value range, a scratch or protrusion Is determined. The scratches or protrusions that can be detected by the work quality inspection device 1 have a width of 200 μm or more and a depth or height of 200 μm or more. Of course, it is also possible to detect a saw mark as described above, a gentle curve over the entire work, or the like by a method similar to the above-described method of determining a scratch or protrusion.

Next, the overall control operation of the work quality inspection apparatus 1 will be described with reference to the flowchart of FIG.
Such overall control operation is executed by a microcomputer (not shown) of the external control device 73. When the external control device 73 is powered on, it is set to an online mode in which a quality inspection can be performed. First, if the standby signal indicating that the quality inspection is in standby is turned on (step S1), the process proceeds to step S2. If there is an ESC input from the data input device 75 (such as a trackball) or the external personal computer 76 in step S2 (ON), the standby signal is turned off (step S3), and the parameters (work type, judgment value, reference value,
The process proceeds to an offline process (step S4) for setting system values and the like, and returns to step S1.

On the other hand, if there is no ESC input in step S2 (OFF), the flow advances to step S5 to wait for input of an inspection start signal. Then, the work detection sensor 67R,
If an external inspection start signal output from 67L is input (ON), the process proceeds to step S6. Step S
In 6, the standby signal is turned off, the OK / NG signal for outputting the quality determination result (good (OK) / defective (NG)) of the work W is turned off, and the in-process signal for executing the quality inspection is turned on. To be. As a result, the quality inspection at the inspection point P1 of the work W is performed (step S7), the quality measurement of the work W and the good / bad judgment are performed, and the OK / NG signal of the judgment result is output from the preceding shooter 18 or the side shooter 19R, 19L (step S8). The processing modes in steps S7 and S8 are the same as the processing procedures in the flowchart shown in FIG.

In steps S9 to S11, the quality inspection and the pass / fail judgment at the inspection point P2 of the work W are executed by the automatic input of the interrupt signal (inspection start signal) based on the timer measurement, and the OK / NG signal is output. It is output to the preceding shooter 18 or the side shooters 19R, 19L. Also in steps S12 to S14, the quality inspection and the good / bad judgment at the inspection point P3 of the work W are executed by the timer counting, and the OK / NG signal is output to the preceding shooter 18 or the side shooters 19R and 19L. Steps S10, S11, S13, S
Also in 14, the same quality inspection processing as in steps S7 and S8 described above is executed. As described above, when the quality inspection and the good / bad determination at the inspection points P1 to P3 are completed, the in-process signal is turned off (step S1).
5) The process returns to step S1.

As described above, according to the work quality inspection apparatus 1 of this embodiment, the first and second slit light sources 10
First and second slit images 7 projected and projected by irradiating slit light from R and 10L on both surfaces of the work W at the same position
9R and 79L are simultaneously imaged by the first and second imagers 11R and 11L, and the first and second slit images 79R and 79R,
Since the quality such as thickness and flaw is determined based on each image data of 79L, the quality of the work W can be measured with high accuracy only by one exposure scan. For example, a saw mark of a sintered magnet can be simultaneously detected from both surfaces of the work.

In the above embodiment, the slit light source and the image pickup device are arranged on the left and right sides of the work, respectively, and the quality is measured with the work in the thickness direction. However, the present invention is not limited to this. For example, a configuration may be employed in which the slit light source and the image pickup device are arranged above and below the work, respectively, and the quality is measured with the thickness direction of the work being oriented vertically.

In the above embodiment, each of the slit image data 79R and 79L on both surfaces of the work is converted into the image
1, the quality of the work is determined based on the image data of the synthesized image 83. However, the present invention is not limited to this, and the slit image data of the entire surface of the work and the standard slit image data corresponding thereto are compared. In addition to the comparison, the slit image data of the other surface of the work and the corresponding standard slit image data can be separately compared, and the work quality can be determined using the individual comparison results.

In the present invention, the quality must not necessarily be measured while the work is running. For example, the quality can be measured while the work is stopped at the irradiation position of the slit light source. In that case, one slit light source is sequentially moved to positions on both sides of the work (for example, positions 10R and 10L in FIG. 6) to irradiate slit light to both surfaces of the work at the same position, or It is also possible to sequentially move the image pickup devices to positions on both sides of the work (for example, positions 11R and 11L in FIG. 6), and capture slit images on both surfaces of the work at the same position.

[0046]

As described above in detail, according to the work quality inspection method according to the present invention, slit light is irradiated on both surfaces of the work at the same position, and a slit image is projected. Each of the slit images projected on both surfaces of the work in this manner is captured by an image pickup device. Therefore, the quality of the work is determined based on each of the captured slit image data. Therefore, compared to a conventional technique in which only one side of the work is irradiated with slit light and imaged, even if the work has irregularities on both sides, or the thickness is uneven, or
Even when the whole is curved, the quality judgment can be performed with high accuracy.

When using a standard work of known quality in the work quality inspection method or apparatus according to the present invention, the standard slit image data on both sides of the standard work and the slit image data on both sides of the inspection work are compared. The work quality is determined based on the comparison results. Therefore, it is suitable for inspecting a large number of works manufactured to the same size and shape by standard, and the quality of the work can be determined with high accuracy.

When the work is moved to the position where the slit light is irradiated, the slit images projected on both surfaces of the work at the same position during the movement are synchronously imaged. By running the workpieces in this way, a large number of workpieces can be inspected quickly and productivity is good. On the other hand, there is a possibility that the measurement error may increase due to the vibration caused by the traveling of the work, but even in such a case, the slit light irradiation and the synchronous imaging are performed on both surfaces of the work, so that the error caused by the traveling is small and the measurement is performed accurately. Can be. In addition, it is also possible to determine the quality of a workpiece that is continuous in the traveling direction.

Further, since the works located at the same position are measured simultaneously from both sides thereof, it is suitable for detecting a thickness which cannot be judged from one side as the work quality. That is, for example, even if the work has irregularities on both surfaces, the thickness can be measured very accurately.

The work is arranged in a posture in which the thickness detecting surface is substantially in the direction of gravity, for example, in a standing posture. In this posture, the slit light is applied to the measurement surfaces on both sides of the work. Therefore, since dust and the like do not accumulate on the light irradiation surface of the work, the thickness measurement accuracy is further improved. Also, even if there is a vertical movement of the work that is likely to occur due to gravity,
Does not affect measurement accuracy.

Then, the work is carried into the light irradiation position by the work carrying means, and the slit light is irradiated on both surfaces of the work. After the light irradiation, the work is carried out from the light irradiation position by the work carrying means. In this case, the transfer speeds of the work loading means and the work unloading means are made substantially the same by the transfer speed control means. Therefore, the transfer of the work between the work loading means and the work unloading means is smooth, and the transfer speed of the work does not change at the light irradiation position. This allows
Since the quality measurement can be performed with less blur of the work, the measurement error can be reduced.

Further, the work traveling by the work carrying means is conveyed while being held by the work carrying means and the work carrying means at the same time when passing through the light irradiation position. As a result, the work travels with the front and rear firmly grasped,
There is no blurring during light irradiation. Therefore, the quality of the work can be accurately determined. In addition, the delivery of the work between the work carrying means and the work carrying means is ensured.

[Brief description of the drawings]

FIG. 1 is a plan view showing a work quality inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the work quality inspection device.

FIG. 3 is a front view of the work quality inspection device.

FIG. 4 is a configuration diagram illustrating a driving and transporting configuration of a work loading unit, a work unloading unit, and a transport speed control unit.

FIG. 5 is an end view cut along the line AA in FIG. 4;

FIG. 6 is a control configuration diagram of the work quality inspection device.

FIG. 7 is a schematic diagram illustrating a state in which first and second slit light sources and first and second image pickup devices capture first and second slit images on both surfaces of a workpiece when viewed from below.

FIG. 8A is a diagram showing an entire work image and a first slit image on the right surface of the work taken by a first imaging device;
(B) is a figure which shows the whole workpiece | work image and the 2nd slit image of the workpiece | work left surface imaged by the 2nd imaging device.

FIG. 9 is a plan view showing a work in a standing posture in which a plurality of measurement points are set.

FIG. 10 is a side view of the work corresponding to FIG. 9;

FIG. 11 is an explanatory diagram showing a mode of combining first slit image data and second slit image data.

FIG. 12 is a flowchart illustrating a control procedure in a quality inspection process.

FIG. 13 is an explanatory diagram showing an aspect of a divided window relating to a first slit image.

FIG. 14 is a flowchart showing an overall control procedure of the work quality inspection apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work quality inspection apparatus 10R 1st slit light source 10L 2nd slit light source 11R 1st imaging device 11L 2nd imaging device 12 Irradiation position 20, 33R, 33L, 40R, 40L, belt drive part 32, 39, 46, 52 Belt body 53 Work carry-in means 54 Work carry-out means 56 Transfer speed control means 68R, 68L Slit light 72 Work quality judgment means 79R First slit image 79L Second slit image 79R1, 79R2, 79R3 First slit image 84R First standard slit image 84L 2 Standard slit image W Work

Continued on the front page (72) Inventor Kazumi Ishida 2-15-17 Egawa, Shimamoto-cho, Mishima-gun, Osaka Prefecture Sumitomo Specialty Metals Co., Ltd.Yamazaki Works (72) Inventor Kiyofumi Nakamura 1850 Minato, Wakayama City, Wakayama Prefecture F term (reference) 2F065 AA61 BB13 CC25 DD03 FF04 HH05 JJ03 JJ16 JJ23 JJ26 MM03 PP15 QQ25 RR07 2G051 AA90 AB02 AB20 BA01 BA20 CA03 CA04 CA07 CD07 DA06 EB01 EB02 ED07 ED23 5B003 AA02 DC

Claims (9)

[Claims] 1. A work at a same position obtained by irradiating a slit light to a work, taking an image of both surfaces of the work at the same position by an image pickup device arranged outside the irradiation light axis of the slit light, and taking an image by the image pickup device. A work quality inspection method characterized by determining the quality of a work based on each slit image data on both surfaces. 2. A work at the same position obtained by irradiating a slit light to the work, imaging both surfaces of the work at the same position by an image pickup device arranged outside the irradiation light axis of the slit light, and imaging by the image pickup device. Each slit image data of both sides,
The standard slit images projected on both sides of the standard work of known quality are compared with each standard slit image data on both sides of the standard work at the same position obtained by imaging with the imager, and the quality of the work is determined based on the comparison result. A work quality inspection method characterized by determining. 3. The apparatus according to claim 1, wherein the workpiece is moved to a position irradiated with the slit light, and the slit images on both surfaces of the workpiece at the same position during the traveling are synchronously captured by an image pickup device. Work quality inspection method described. 4. The work quality inspection method according to claim 1, wherein the quality of the work is a thickness. 5. The work quality inspection method according to claim 4, wherein the work is arranged so that the thickness detection surface is substantially in the direction of gravity, and both sides of the work are irradiated with slit light. 6. A slit light source for irradiating a slit light to a workpiece, a first imager arranged outside of an irradiation optical axis of the slit light source to capture a first slit image projected on one surface of the workpiece, and a slit light source. A second imager arranged outside the irradiation optical axis to capture a second slit image projected on the other surface of the work, and a first image of the work at the same position output from the first imager and the second imager respectively The result of comparing the slit image data and the second slit image data with the first standard slit image data and the second standard slit image data at the same position respectively obtained by irradiating and imaging both surfaces of a standard work of known quality, respectively. A work quality inspection apparatus comprising: a work quality determination unit that determines the quality of a work based on the work quality. 7. A work carrying means for carrying a work to a slit light irradiation position, a work carrying means for carrying out a work from the slit light irradiation position, a work carrying speed by the work carrying means, and a work carrying by the work carrying means. 7. The work quality inspection apparatus according to claim 6, further comprising a conveyance speed control unit that makes the speed substantially the same. 8. A work carrying-in means and a work carrying-out means, each comprising a pair of belt bodies for sandwiching and carrying a work from both sides, and the work carrying-in means when passing through a slit light irradiation position. 8. The work quality inspection apparatus according to claim 7, wherein the work carrying means simultaneously holds and carries the work. 9. The work quality inspection apparatus according to claim 6, wherein the quality of the work is a thickness.