JPH07243825A - Inspection of wire material - Google Patents

Abstract

PURPOSE:To judge whether the covering condition of a peeled part and a conductor are good or defective by obtaining the concentration value of gradation images of the peeled part and its adjacent part in a extracting line of diametral direction, setting a central point as an edge of a wire material at the time when the tilt of an approximate straight line of picture elements, performing the same operation in a lengthwise direction repeatedly, and comparing the result with the edge width of a reference extracting line. CONSTITUTION:In order to judge the outer diameter of a cover 2 of a wire material 1 and the outer diameter of a conductor 3, the concentration value of taken gradation images in a extracting line II of diametral direction is obtained the tilt of an approximate straight line for a plurality of picture elements (odd) within a window, for example, vertical five picture elements is calculated, and a central point P at the time when the straight line tilts at a specified value or more is set as the edge of an object. The detecting operation is performed for a plurality of wires, with an equal internal in a lengthwise direction of the material, and the results are compared with the edge width of a reference extracting line IIs at a position apart a specified distance from the peeled part, thereby inspecting cracks, resin remnants, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a metal crimping terminal to crimp-connect an end of a wire rod which is stripped to a certain length to an intermediate stripping portion which is stripped of a coating from an intermediate portion of the wire rod. In this case, the present invention relates to a method for inspecting a linear material for inspecting the quality of peeling of the intermediate peeling portion.

[0002]

2. Description of the Related Art When wire terminals are crimped to each other, for example, in the middle of a trunk by crimping a metal terminal, the trunk 1 should be connected as shown in FIG. 20 (hereinafter referred to as "intermediate peeling portion"). 21 and FIG. 2 while stripping the coating 2 of No. 2 over a predetermined length to bare the core wire 3 and stripping the end of the coating 5 of the branch wire 4 for a given length to bare the core wire 6.
As shown in FIG. 2, the core wire 6 of the branch wire 4 is crimp-connected to the core wire 3 of the main wire 1 by the crimp terminal 7 or 8.

When crimping the core wire 3 of the trunk line 1 and the core wire 6 of the branch line 4 in this manner, as shown in FIG.
It is necessary to surely peel off the coating 2 of the intermediate portion of the above for a predetermined length L. The peeling of the middle part of this coating 2
Since it is automatically performed by the intermediate peeling machine, defective peeling may occur. For example, as shown in FIG.
23. The crack defect that the cut 2a of the peeled portion of the
As shown in (c), some of the plurality of strands 3a forming the core wire 3 are cut (partially broken conductor), core wire breakage failure, FIG. 23 (d).
As described above, the peeling is incomplete and a part of the coating 2b remains, such as defective resin fogging.

[0004]

Conventionally, each inspection of such a peeled portion has been conducted by visual inspection. However, along with the automation of the entire wire material processing apparatus, it has been demanded to automate the peeling inspection of the peeling portion where the intermediate portion of the coating 2 is peeled off.

An apparatus or method for stripping off the coating of the end of the covered wire and inspecting the quality of the crimp terminal in which the crimp terminal is connected to the end of the core wire is disclosed in, for example, JP-A-5-15752.
Terminal crimping position inspection device disclosed in Japanese Patent Publication No.
There is a crimp terminal inspection method disclosed in Japanese Patent Publication No. 15977. All of them are for optically inspecting the wire material in the crimping portion of the crimping terminal for defective resin biting, neck hanging, defectiveness, protruding core wire and the like.

The former irradiates a slit-shaped laser beam from above the crimping portion, captures the reflected light into the camera obliquely from above, captures the captured image as a light trace of irregularities of the outer diameter of the terminal, and measures the change. Then, the quality of the crimped state is inspected. However, this inspection method can inspect when the object to be inspected is accurately positioned, but it requires a mechanical mechanism that accompanies it, and the inspection device becomes expensive. In addition, there is a problem in that it is not possible to inspect for the protrusion of the core wire due to a single slit light trace.

In the latter, the transmitted light from the side is used to capture the shadow of the crimp terminal as an image, and the quality of the crimped state is inspected from the unevenness. Therefore, in this inspection method, it is necessary to devise a mechanical mechanism for capturing an image of the side surface. The present invention has been made in view of the above points, and provides a method for inspecting a linear material, which optically inspects the quality of peeling of a portion where the coating other than the end of the wire is stripped for a predetermined length. With the goal.

[0008]

In order to achieve the above object, according to the present invention, a stripped part in the middle of a wire and its vicinity are illuminated by transmitted illumination to obtain a grayscale image of the striped part, and The density value of a vertical line is calculated to calculate the slope of an approximate straight line for multiple pixels, and the point in the middle when the slope becomes a certain value or more is taken as the edge of the wire rod, and such an operation is performed in the longitudinal direction of the wire rod. Along the same time multiple times,
The quality of the coating of the peeling portion and the core wire is determined by comparing with the edge width of the reference vertical line.

Further, the stripped part in the middle of the wire and its vicinity are illuminated by transmitted illumination to obtain a grayscale image thereof, and the grayscale image is binarized to trace the edge of the outer periphery of the stripped part and to approach them. By calculating the slope of the approximate straight line of a plurality of pixels, the middle point when the slope becomes a certain value or more is determined as the boundary between the coating and the core line to determine the quality of the peeling part. is there.

Further, the stripped part in the middle of the wire and its vicinity are illuminated by transmitted illumination to obtain a grayscale image, the density value of the vertical line in the diameter direction of the wire is obtained, and the inclination of the approximate straight line for a plurality of pixels is tilted. Is calculated, the middle point when the inclination becomes a certain value or more is the edge of the wire rod, and such an operation is performed a plurality of times at equal intervals along the longitudinal direction of the wire rod,
By comparing the edge width of the reference vertical line with the quality of the covering and core wire of the peeling portion, the grayscale image is binarized to trace the edge of the outer periphery of the peeling portion, and a plurality of adjacent pixels Is calculated, and the middle point when the inclination becomes equal to or larger than a certain value is discriminated as the boundary between the coating and the core line, and the quality of the peeling portion is discriminated.

[0011]

[Operation] Illuminating the stripped portion of the wire with transmitted illumination, obtaining the density value of the vertical line in the diametrical direction of the grayscale image, calculating the inclination of the approximate straight line for a plurality of pixels, and calculating the inclination when the inclination exceeds a certain value. The point in the middle is the edge of the wire. This operation is performed a plurality of times at equal intervals along the longitudinal direction of the wire rod, and the quality of the coating of the peeling portion and the core wire is determined by comparing with the edge width of the reference vertical line. Further, the grayscale image is binarized to trace the edge of the outer periphery of the peeling portion, the slope of the approximate straight line of a plurality of pixels in the vicinity of the grayscale image is calculated, and the slope of the middle when the slope becomes a certain value or more is calculated. The point is discriminated as the boundary between the coating of the peeling portion and the core wire. This determines the quality of the peeled part

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an outline of an inspection apparatus for carrying out a method for inspecting a stripped portion of a linear material according to the present invention.
Is an apparatus for inspecting the quality of peeling of a peeled portion where the coating is stripped off in the middle of the wire (hereinafter, referred to as “mesh peeling inspection” for convenience of description). An image processing unit 12 that picks up an image of the peeled part with a camera, determines the quality by performing image processing by capturing the image, a control unit (sequencer) 13 that controls the image processing unit 12, and a process and result of the image processing are displayed. Display (CRT) 14
It is composed by. The inspection start, the inspection, and the inspection result (pass / fail result) are controlled and monitored via the control unit 13. The image processing unit 12 receives necessary data of the inspection object (wire material) from the control unit 13 at the time of initializing, waits for a start signal, processes, and outputs the result. Then, the process and result of the processing are displayed on the display unit 14.

It is indispensable to efficiently and easily perform the processing in the inspection. For this reason, characterization of the data to be processed, for example, something that serves as a standard such as "is easily distinguishable" and "has regularity" is required. In addition, the feature amount of data may be affected by the surrounding environment, and before the data is taken in, that is, how to perform the previous process is also an important factor. In particular, the feature amount of data in image processing is greatly influenced by how the optical system using the illumination, the lens, the camera, etc. is configured.

According to the present invention, the object to be inspected, that is, the stripped portion of the wire is caught as a shadow, and the grayscale data is image-processed. Therefore, the illumination unit 11 is a transillumination device and is configured as shown in FIG. That is, the lens 16 and the light projector (light source) 17 of the camera 15 are arranged and fixed so as to be spaced apart and face each other, and the peeling portion 1a of the trunk line (hereinafter referred to as "wire material") 1 is horizontally arranged at substantially the center. Has become. The projector 17 is a flat light guide in which the irradiation unit 17a has a flat plate shape and irradiates the wire rod 1 with parallel rays as indicated by an arrow. Floodlight 17
, The irradiation portion 17a has uniform surface emission, and by using this as transmitted light, the shade of the wire 1 can be captured. The camera 15 is, for example, a camera of a type using a CCD solid-state image sensor, and the input image from the lens 16 is a binary image of white and black as a brightness gradation of 0 to 255 steps, that is, binarized and a corresponding signal is obtained. Output.

Further, in the inspection apparatus 10, the illumination unit 11 and the image processing unit 12 are fixed, so that the image data of the stripped portion 1a of the wire rod 1 obtained is in only one direction. Therefore,
A mechanism for mechanically rotating the wire rod 1 is provided so that image data of the peeling portion 1a from multiple directions can be taken in. That is, the wire rod 1 is rotated as shown in FIGS.
Images of 360 ° are captured from 4 directions in increments of 0 °.

4 to 6 show an example of a rotary gripping mechanism 20 for gripping and rotating the wire 1. Rotating gripping mechanism 2
0 is a support plate 2 provided with notches 22a, 22a that are opened in a substantially U-shape on each upper end of the base 21 and take in a wire rod.
2 and 22 are vertically provided at a predetermined interval, and each of the support plates 22 and 22 has a disk-shaped notch 22a on the inner side thereof.
A pair of discs 2 that can be aligned with 22a and are provided with notches 23a, 23a that are open to the outer periphery and take in the wire rod in the center.
3, 23 are rotatably supported. The rotary shaft 24 is
Gears 25, 25, which are horizontally and rotatably supported by the support plates 22, 22 and are fixed to the rotary shaft 24, mesh with teeth engraved on the outer peripheral surfaces of the discs 23, 23, and The discs 23, 23 are rotated.

The gripping mechanism 26, 26 has support plates 22, 22.
Is arranged outside and fixed to the corresponding discs 23, 23, and rotates integrally with these discs 23, 23 to grip the wire 1 and hold it at the center position. Further, outside the gripping mechanisms 26, 26, support members 27, 27 having a bifurcated shape and supporting the wire rod are vertically provided. The drive motor 28 is mounted on the base 21, connected to the rotary shaft 24 via a joint, and connected to the disc 23 via gears 25, 25.
It is designed to rotate 23.

On the support plates 22, 22, the camera 15 and the lens 1 are arranged on one side of the wire 1 which is held horizontally at the central positions of the disks 23, 23 by the gripping mechanisms 26, 26.
On the other side, the light projectors 6 are arranged and fixed so as to face each other at a predetermined interval. As a result, the camera 15 can capture the image of the peeling portion 1a of the wire rod 1 from the four directions in 90 ° increments in four directions as shown in FIGS. 3 (a) to 3 (d). That is, the inspection device 10 has four peeling parts for one peeling part.
The screen is inspected and this is one cycle process. still,
The processing time required to inspect one screen is about 0.4 seconds at maximum.

In the medium inspection, the object is a single wire,
A relatively easy inspection is possible. Further, the configuration of the illumination system is also a simple flat type configuration as described above. FIG. 7 shows an inspection flow from image capturing to result output. As is clear from this flow, the inspection flow starts from image capturing and is performed step by step for each block of the inspection method. That is, when the image capture signal is input (step S1), the object detection window is set (step S2), the inspection method 1 (step S3), and the inspection method 2 are set.
After (step S4), the quality of the inspection result of the peeled portion is output (step S5).

At this time, one cycle of processing is limited to a few seconds and the time required for inspection is limited.
It needs to be as concise as possible. With that in mind,
When capturing an image, after detecting the inspection object on the screen,
The window of the necessary data part is cut off, and the other data is invalid. Further, since the inspection object is a wire rod, it is possible to cut a window of about a quarter of one screen in the inside skin inspection.

Next, the window setting method will be described. As shown in FIG. 8, the shade of the wire rod 1 is captured as an image by the projector 17 (flat plate light guide) of the illumination unit 11. At this time, the portion other than the wire rod enters the camera 15 as direct light so that the luminance value (for example, the value expressed as gradation of 0 to 255 steps) becomes constant at the maximum brightness. As a result, the luminance becomes darker in the portion of the wire, and a window having a certain vertical distance d, d is cut out as indicated by dotted lines I, I with the points P, P where the luminance changes abruptly. The vertical lines of the solid lines II and II (in the diameter direction of the wire) are the background luminance values and the dotted lines III and I.
The vertical line II indicates the luminance value of the darkest wire rod portion.

In the inspection method 1, the size is discriminated by the number of pixels on the extraction line II, and as shown in FIG. 9, the outer diameter dimension (cross section width) a of the coating 2 of the wire rod 1 and the outer diameter dimension of the core wire 3. (Cross section width) b is determined. That is, the density value is obtained for the vertical line II of the captured grayscale image, and the inclination of the approximate straight line V for a plurality of pixels (odd number) in the window, for example, 5 pixels in the vertical direction is calculated as shown in the enlarged view of FIG. , The middle point p at the time when the straight line is inclined to a certain value or more is the edge of the object. Since the uniform direct light of the transmitted light is incident on the background portion, it is found that the inclination is small, and the edge of the object can be detected stably. As shown in FIG. 11, this extraction line is laterally, that is, N lines (for example, 128 lines) are arranged at predetermined intervals along the longitudinal direction of the wire rod 1, and the edge width of the reference line IIs at a position apart from the skin peeling part by a predetermined distance. (Coating 2
From the outside diameter), the crack defect in the peeled part (Fig. 2
3 (b)), defective resin fading (FIG. 23 (d)) and the like.

The inspection method 2 is the same image as the inspection method 1
The length of the peeling portion is discriminated by changing the unevenness of the image by performing the binarization process, and the changing position of the peeling portion of the wire rod 1 is measured as shown in FIG. Since the background portion of the wire 1 has a uniform brightness, the threshold value is fixed and only the object can be detected as shown in FIG. After binarization, arrows A and B
As shown in FIG. 14, the edge of the outer periphery of the wire rod 1 is traced, a plurality of adjacent pixels (odd number), for example, the inclination of the approximate line VI of 5 pixels is calculated as shown in FIG. Let point q be the change point of the object. This change point is the boundary of peeling, that is, the stepped portion between the coating 2 and the core wire 3. The length of the peeled portion is measured from the distance between the change points on both sides of the peeled portion.

Then, according to the inspection methods 1 and 2, there is no peeling, a peeling width (FIG. 23A), and a resin fading (FIG. 23).
(D)) can be inspected, and when the state of the captured image is good, resin cracks (Fig. 23).
(B)), core wire breakage (Fig. 23 (c)) can be inspected. Of course, each of these inspection methods has its own criteria for inspection determination (depending on the size of the image, etc.), and therefore the captured image to be inspected needs to be within the determination criteria.

Returning to FIG. 1, the image signal output from the camera 15 in the image processing unit 12 is the camera adapter 30.
Is input to the image processing device 31 via. The image processing device 31 binarizes and shades the input image signal, outputs the result, and displays it on the display unit 14. The inspection start, the inspection, and the inspection result (pass / fail result) are controlled and monitored via the control unit 13. The image processing device 31 receives necessary data of the inspection object (wire material) from the control unit 13 at the time of initialization, waits for a start signal, binarizes and shades the input image signal, and outputs the result. Then, the process of the image processing device 31 and the result are
It is displayed on the display unit 14.

The inspection method of the peeling portion will be described below with reference to the timing flow charts shown in FIGS. 15 and 16 and the operation timing charts shown in FIGS. First, at the time of the inspection initial, the control unit (sequencer) 13 sends data necessary for inspection such as an initial signal, an inspection start signal, and a data writing signal to the image processing device 31 (see FIG. 1).
7 (e), (a), (c)). When an initial signal is input from the control unit 13 (step S1 in FIG. 15) and then an inspection start signal is input (step S2), the image processing device 31 starts reading necessary data (step S3, FIG. 17 (b)), and the data is read (steps S4, S5, FIG. 17 (d)). Next, the image processing device 3
1 sets the number of inspections (step S6 in FIG. 16) and determines whether or not the cycle start signal is input from the control unit 13 (step S7). When the cycle start signal is not input, the process proceeds to step S9 and the inspection is performed. Wait until the start. The number of inspections in step S6 is
Four times for inspecting the peeled portion by 90 ° in 360 °. In addition, in FIG. 17, reference numeral (SI) indicates a signal on the sequencer side, and reference numeral (image) indicates a signal on the image processing apparatus side.

When the image processing apparatus 31 receives an inspection start signal (FIG. 18A) from the control section 13 (step S9), it starts operating and the first position of the peeling section from the camera adapter 30, that is, 0. A rotary gripping mechanism for fetching an image signal at a position (Fig. 3 (a)) (step S10, Fig. 18 (d)) and starting processing of the selected pattern (step S11), and gripping and rotating the wire 1 at the same time. 20 (Fig. 4
~ FIG. 6), the timing of the start of rotation (FIG. 1
8 (a)). The determination result of step S12 is negative (NO)
The adjacent image processing apparatus 31 ends the first image processing (step S13) and returns to step S7. The number of inspections is decremented by 1 to be 3, and the second inspection, that is, the inspection of the peeling portion at the position rotated by 90 ° (FIG. 3B) is performed (steps S9 to S13). Rotating gripping mechanism 20
Rotates the wire 1 from the inspection start position of FIG. 3 (a) (FIG. 18 (c)), and the image processing apparatus 31 has a peeling portion of 0 °.
Each time the image is rotated by 90 °, the image is sequentially captured and processed.

The image processing device 31 reads the inspection result (FIGS. 19A to 19C), and the inspection number is a predetermined number (4).
When the number of times reaches, the inspection is ended, the read inspection result is output to the control unit 13 (step S14), the image processing is ended (step S15), and the process proceeds to step S16. When the initial signal (FIG. 17 (e)) is output in step S16, the image processing device 31 performs step S16.
2, the process returns to step S6 when no output is made. Then, the inspection result is displayed on the display unit 14,
The quality of the stripped portion of the wire 1 is determined.

[0029]

As described above, according to the present invention, it is possible to automatically determine the quality of peeling of the peeling portion in the middle portion of the wire, and to quickly and favorably determine the quality of the peeling portion. Therefore, the working efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an inspection apparatus for carrying out an inspection method for a linear material according to the present invention.

FIG. 2 is a cross-sectional view showing an outline of an illuminating section that illuminates the wire rod of FIG. 1 by transmission illumination.

[Fig. 3] Rotate the wire rod of Fig. 1 by 360 ° and rotate it by 90 °.
It is explanatory drawing which inspects a peeling part from a direction.

FIG. 4 is a plan view showing an embodiment of a rotary gripping mechanism for rotating the wire rod of FIG.

FIG. 5 is a front view of FIG.

FIG. 6 is a side view of FIG.

FIG. 7 is a flowchart showing an outline of an inspection procedure in the present invention.

FIG. 8 is a diagram showing an example of a window set in the image processing of the present invention.

FIG. 9 is an explanatory diagram of a first-stage inspection method for a stripped portion of a wire rod.

FIG. 10 is an explanatory diagram showing an example in which the inspection of FIG. 9 is performed using the window shown in FIG.

11 is an explanatory diagram showing an example for inspecting a peeling portion by the inspection method of FIG.

FIG. 12 is an explanatory diagram of a second-stage inspection method for a stripped portion of a wire rod.

FIG. 13 is an explanatory diagram showing a state in which the image of the peeling portion in FIG. 12 is binarized.

14 is an explanatory diagram showing a method of detecting an edge of a peeling portion from the image of FIG.

15 is a diagram showing a part of a timing flow of image processing in the inspection apparatus of FIG.

16 is a diagram showing the rest of the timing flow of FIG.

FIG. 17 is a diagram showing an operation timing chart of the inspection apparatus of FIG. 1 at the time of inspection initials.

18 is a diagram showing an operation timing chart when the inspection of the inspection apparatus of FIG. 1 is started.

19 is a diagram showing an operation timing chart when the inspection result of the inspection device of FIG. 1 is output.

FIG. 20 is an explanatory diagram of connecting a terminal of a branch line in the middle of a trunk line.

21 is a diagram showing a first mode in which the trunk line and the branch line of FIG. 20 are connected by a crimp terminal.

22 is a diagram showing a second mode in which the trunk line and the branch line of FIG. 20 are connected by a crimp terminal.

FIG. 23 is a diagram showing a peeled state of the peeling portion where the coating is peeled off in the middle of the main line of FIG. 20.

[Explanation of symbols]

 1 wire rod (main line) 2, 5 coating 4 branch wire 3, 6 core wire 7, 8 crimping terminal 10 inspection device 11 illumination unit 12 image processing unit 13 control unit 14 display unit 15 camera 16 lens 17 light emitter 20 rotary gripping mechanism 30 camera adapter 31 Image processing device

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[Procedure amendment]

[Submission date] April 12, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 3

[Correction method] Change

[Correction content]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

[0008]

In order to achieve the above object, according to the present invention, a stripped part in the middle of a wire and its vicinity are illuminated by transmitted illumination to obtain a grayscale image of the striped part, and The density value of the extraction line is calculated to calculate the slope of the approximate straight line for multiple pixels, the middle point when the slope becomes a certain value or more is taken as the edge of the wire, and such operation is performed in the longitudinal direction of the wire. Is performed a plurality of times at equal intervals along the line to compare the edge width of the reference extraction line with the quality of the coating of the peeling portion and the core wire.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Further, the stripped part in the middle of the wire and its vicinity are illuminated by transmitted illumination to obtain a grayscale image thereof, the density value of the extraction line in the diameter direction of the wire is obtained, and the inclination of the approximate straight line for a plurality of pixels is tilted. Is calculated, and the point in the middle when the inclination becomes a certain value or more is set as the edge of the wire rod, and such an operation is performed a plurality of times at equal intervals along the longitudinal direction of the wire rod, and the edge width of the reference extraction line is calculated. In comparison with the above, the quality of the covering and core wire of the peeling portion is determined, the grayscale image is binarized, the edge of the outer periphery of the peeling portion is traced, and the inclination of the approximate straight line of a plurality of adjacent pixels is calculated. However, the quality of the peeling portion is determined by determining the middle point when the inclination becomes a certain value or more as the boundary between the coating and the core wire.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

[0011]

[Function] Illuminating the stripped portion of the wire material with transmitted illumination, calculating the density value of the extraction line in the diameter direction of the grayscale image, calculating the inclination of the approximate straight line for a plurality of pixels, The point in the middle is the edge of the wire. Perform this operation multiple times along the longitudinal direction of the wire at regular intervals to
The quality of the coating of the peeling portion and the core wire is determined by comparing with the edge width of the outgoing line. Further, the grayscale image is binarized to trace the edge of the outer periphery of the peeling portion, the slope of the approximate straight line of a plurality of pixels in the vicinity of the grayscale image is calculated, and the slope of the middle when the slope becomes a certain value or more is calculated. The point is discriminated as the boundary between the coating of the peeling portion and the core wire. As a result, the quality of the peeled portion is determined .

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

Next, the window setting method will be described. As shown in FIG. 8, the shade of the wire rod 1 is captured as an image by the projector 17 (flat plate light guide) of the illumination unit 11. At this time, the portion other than the wire rod enters the camera 15 as direct light so that the luminance value (for example, the value expressed as gradation of 0 to 255 steps) becomes constant at the maximum brightness. As a result, the luminance becomes darker in the portion of the wire, and a window having a certain vertical distance d, d is cut out as indicated by dotted lines I, I with the points P, P where the luminance changes abruptly. In addition, the solid line II, the extraction line of II (the direction orthogonal to the diameter direction of the wire and the illumination direction)
Direction ) indicates the background luminance value, and the extraction lines of the dotted lines III and III indicate the luminance value of the darkest wire rod portion.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

The inspection method 1 is an extraction line (vertical line) I
The size is determined by the number of pixels on I, and the outer diameter dimension (cross section width) a of the coating 2 of the wire rod 1 and the outer diameter dimension (cross section width) b of the core wire 3 are determined as shown in FIG. That is, the density value is obtained for the extraction line II of the captured grayscale image, and a plurality of pixels (odd number) in the window, for example, the inclination of the approximate straight line V for 5 pixels in the vertical direction is calculated as shown in the enlarged view of FIG. , The middle point p at the time when the straight line is inclined to a certain value or more is the edge of the object. Since the uniform direct light of the transmitted light is incident on the background portion, it is found that the inclination is small, and the edge of the object can be detected stably. As shown in FIG. 11, this extraction line is performed in the lateral direction, that is, along the longitudinal direction of the wire rod 1 at a predetermined interval of N (for example, 128), and the reference extraction line IIs at a position apart from the peeling portion by a predetermined distance.
From the comparison with the edge width (outer diameter of the coating 2), the cracking defect in the peeled portion (FIG. 23B), the resin scraping defect (FIG. 2).
3 (d)) etc. are inspected.

Claims (6)

[Claims] 1. A densified image is obtained by illuminating a peeling part in the middle of a wire rod and its vicinity with transmitted illumination, and a density value of a vertical line in the diameter direction of the wire rod is obtained to obtain an inclination of an approximate straight line for a plurality of pixels. Is calculated, and the point in the middle when the inclination becomes a certain value or more is taken as the edge of the wire rod, and this operation is performed multiple times at equal intervals along the longitudinal direction of the wire rod, and the edge width of the reference vertical line A method for inspecting a linear material, characterized in that the quality of the coating of the peeled portion and the core wire is determined in comparison with. 2. A densified image is obtained by illuminating a peeling part in the middle of a wire and its vicinity with transmitted illumination.
Performing the value-processing to trace the edge of the outer periphery of the peeling portion, calculating the slope of the approximate straight line of a plurality of adjacent pixels, the center point when the slope becomes a certain value or more between the covering and the core line. A method for inspecting a linear material, which is characterized by determining whether the skin peeling portion is good or bad by determining a boundary. 3. A densified image is obtained by illuminating a peeling part in the middle of a wire rod and its vicinity with transmitted illumination, and a density value of a vertical line in a diameter direction of the wire rod is obtained to obtain an inclination of an approximate straight line for a plurality of pixels. Is calculated, and the point in the middle when the inclination becomes a certain value or more is taken as the edge of the wire rod, and this operation is performed multiple times at equal intervals along the longitudinal direction of the wire rod, and the edge width of the reference vertical line And the quality of the coating and the core wire of the peeling portion are compared with each other, the grayscale image is binarized to trace the edge of the outer periphery of the peeling portion, and the inclination of the approximate straight line of a plurality of adjacent pixels is calculated. Then, the quality of the stripped portion is determined by determining the middle point when the inclination becomes a certain value or more as the boundary between the coating and the core wire. 4. The number of pixels for obtaining the approximate straight line is an appropriate odd number within a range in which the boundary between the coating of the stripped portion and the core can be inspected. The inspection method for the linear material described in. 5. The method for inspecting a linear material according to claim 4, wherein the number of pixels is five. 6. The method according to claim 1, wherein the determination is performed over a range of 360 ° for each predetermined rotation angle by rotating the wire rod.
The method for inspecting a linear material according to any one of 1.