JP2003214825A - Apparatus and method for optically inspecting crimping terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for inspecting a crimping terminal capable of inspecting a crimping part of the crimping terminal from many different angles. <P>SOLUTION: The apparatus for optically inspecting the crimping terminal comprises an illumination means 11 for illuminating the crimping part 1a of the crimping terminal 1 to be inspected, an imaging means 12 for imaging the illuminated crimping part 1a, a judging means 3 for judging good or bad of the part 1a based on imaged image data, a polarized plate 14 for transmitting the light illuminated to the part 1a, and a polarized plate 5 for passing the light reflected by the part 1a as a pair between the means 11 and the means 12 so that the polarized axes of the respective polarized plates is set parallel to each other. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crimp terminal inspecting apparatus and method for discriminating between a metal portion of a crimp terminal and a resin portion of an electric wire jacket.

[0002]

2. Description of the Related Art For example, in a manufacturing process of a wire harness for an automobile, a terminal in which a crimping terminal and an electric wire are crimped has been frequently used in recent years.

Conventionally, in order to judge the quality of the connection between the crimp terminal and the electric wire, in addition to a mechanical test for measuring the connection strength and an electrical test for judging whether or not there is continuity, the presence or absence of a core wire protruding from the crimp terminal, etc. An appearance inspection method for determining the appearance is generally adopted.

As the appearance inspection method, generally, an image pickup process of irradiating the crimp terminal with light to generate a highlight portion and picking up an image of the highlight portion, and image data obtained by the image pickup step. The appearance of inspecting the external appearance of the crimp terminal, such as the presence or absence of the protruding core wire, by counting the pixels with a predetermined density in the image data acquired in the imaging step The inspection method is adopted.

However, in the above appearance inspection method,
Simply illuminate the crimp terminal with light to generate the highlight part,
Since the image data was acquired only by imaging the highlight part of the crimping part in the imaging process, when the white wire jacket is used for the wire connected to the crimp terminal, the wire jacket is used. However, the intensity of the reflected light is almost the same as that of the metal portion, and the contrast of the image obtained by the image pickup means is very poor.

Therefore, various techniques for improving the contrast of a captured image have been developed. For example, in Japanese Unexamined Patent Publication No. 7-27517, an illumination unit that irradiates a crimp portion of a crimp terminal with light, an imaging unit that images the crimp portion, and an image analysis unit that analyzes the image data acquired by the imaging unit are disclosed. There is disclosed a technique of a crimp terminal inspecting device including a. This crimp terminal inspection device is
By installing a deflection filter at an appropriate angle with the front surface of the image pickup means, the gloss of the metal part of the crimp terminal is erased, the luminous intensity of the lighting means is increased, and only the resin part is brightened.
It is configured to inspect the appearance of the crimp terminal.

[0007]

In carrying out the above appearance inspection, the crimping portion of the crimping terminal is a very important portion for evaluating the connection characteristics of the crimping terminal, and whether the core wire sticks out or the crimp shape is good or bad. It is necessary to conduct an inspection including the above.
However, if this part is image processed as a dark part,
There is a problem that it becomes difficult to inspect the above items.

The present invention has been made in view of the above problems. Image processing is performed by providing contrast so that a metal portion is bright and a resin portion is dark, so that misalignment of a crimping position, protrusion of a core wire, or crimping is performed. An object of the present invention is to provide an inspection device and an inspection method for a crimp terminal, which can inspect the crimp portion of the crimp terminal in various directions such as the quality of the shape.

[0009]

In order to solve the above problems, the present invention provides an illuminating means for illuminating a crimp portion including a crimp terminal to be inspected, an imaging means for illuminating the illuminated crimp portion, and an imaging means. A discriminating means for discriminating the quality of the crimping portion based on the image data obtained, and a polarizing plate for transmitting the light irradiated to the crimping portion, and a reflecting portion for reflecting the crimping portion between the illuminating means and the imaging means. In the optical inspection device in which the polarizing plate that transmits the light is arranged in a pair, the polarization axes of the polarizing plates are set to be parallel to each other.

In the present invention, the light emitted from the illuminating means is polarized by the one polarizing plate and reaches the crimping portion including the crimping terminal along the vibration direction defined by the polarization axis of the polarizing plate. This light reaches the imaging means after being reflected by the pressure-bonded portion and then transmitted through the other polarizing plate. here,
Since the polarization axes of both polarizing plates are set to be parallel to each other, the light applied to the metal portion of the pressure-bonded portion is transmitted to the image pickup means without reducing the light amount after passing through the other polarizing plate. On the other hand, the light irradiated on the resin portion is diffusely reflected on the surface of the resin, and therefore, after passing through the other polarizing plate, the light reaches the image pickup means in a reduced light amount.
As a result, in the image obtained by the imaging means, the metal part is bright and the resin part is dark.

Further, another aspect of the present invention is an illumination means for illuminating a crimp portion including a crimp terminal to be inspected, and a dual-view lens barrel for splitting and outputting the light reflected by the illuminated crimp portion. A pair of image pickup means arranged corresponding to the output side of the dual-view lens barrel and for picking up an image of each crimping portion, and a discriminating means for making a pass / fail judgment of the crimping portion based on the image data picked up by each image pickup means. An optical inspection device provided,
A polarizing plate on the illumination side, which is arranged between the illumination means and each image pickup means and polarizes the light irradiated to the pressure-bonded portion, is provided on the output side of the dual-view lens barrel to form a pair, which correspond to each other. An output side polarizing plate that polarizes the light output to the image pickup means, and one of the polarization axes of the output side polarizing plate is set parallel to the polarization axis of the illumination side polarizing plate. Or the other is set in an orthogonal direction, and the polarization axis is orthogonal to the discriminating means from the value of the image signal based on the image data output by transmitting through the polarizing plate whose polarization axis is parallel to the illumination side polarizing plate. It is an optical inspection apparatus characterized in that an analysis unit is provided for performing image analysis based on a value obtained by subtracting a value of an image signal based on image data transmitted through a polarizing plate and output.

In this aspect, the light emitted from the illuminating means is polarized by the polarizing plate on the illuminating side and becomes light along the vibration direction defined by the polarization axis of the polarizing plate and reaches the crimping portion including the crimping terminal. To do. This light is reflected by the pressure-bonded portion, is divided into two, passes through the corresponding polarizing plates, and then reaches the corresponding imaging means. Here, in the present invention, the polarization axis of one of the polarizing plates is set to be parallel to the polarization axis of the polarizing plate on the illumination side, and the polarization axis of any one of the other polarizing plates is set to be orthogonal to each other. In the image data obtained by one of the image pickup means, the metal portion becomes bright and the resin portion becomes dark, and in the image data obtained by the other image pickup means, the resin portion has the same brightness as the one image pickup means. Whereas there are darkened metal parts. Further, the analyzing unit of the discriminating means in this invention transmits the polarizing plate whose polarization axis is orthogonal from the value of the image signal based on the image data output by transmitting the polarizing plate whose polarization axis is parallel to the polarizing plate on the illumination side. Since the image analysis is performed based on the value obtained by subtracting the value of the image signal based on the image data output by the image data obtained, the brightness of the metal portion of the finally obtained image data is the image obtained by one of the image pickup means. Although it is the same as the data, the resin portion is darker than any image data without being affected by the color of the resin. As a result, the contrast between the metal portion and the resin portion is increased.

Another aspect of the present invention is to illuminate a crimp portion including a crimp terminal to be inspected, image the illuminated crimp portion, and determine whether the crimp portion is good or bad based on the imaged image data. In the optical inspection method for performing, the procedure of polarizing the light irradiated to the pressure-bonded portion along one polarization axis, and the light reflected by the pressure-bonded portion, along the polarization axis parallel to the one polarization axis. The optical inspection method is characterized in that the optical inspection method is provided with a procedure of polarization and imaging.

In this aspect, the procedure of polarizing the light irradiated to the pressure-bonded portion along one polarization axis and the procedure of polarizing the light reflected by the pressure-bonded portion along the polarization axis parallel to the one polarization axis are described. Since the light applied to the metal portion of the pressure-bonded portion is polarized along the polarization axis parallel to the one polarization axis, the image pickup means does not reduce its light amount. On the other hand, since the light irradiated on the resin part is diffusely reflected on the surface of the resin, after being polarized along the polarization axis parallel to the one polarization axis, the image is captured with the light amount reduced. . As a result, in the obtained image, the metal portion is bright and the resin portion is dark.

Further, in another preferred embodiment, a crimp portion including a crimp terminal to be inspected is illuminated, the illuminated crimp portion is imaged, and the quality of the crimp portion is determined based on the imaged image data. In the optical inspection method,
A step of polarizing the light irradiated to the pressure-bonded portion along one polarization axis, a bisection procedure of dividing the light reflected by the pressure-bonded portion into two parts, and one of the divided light beams is the one polarization axis. A parallel-wave imaging procedure for imaging by polarization along parallel polarization axes, and an orthogonal-wave imaging procedure for imaging the other of the bisected light by polarization along a polarization axis orthogonal to the one polarization axis. , An image analysis procedure for performing image analysis based on a value obtained by subtracting the value of the image signal based on the image data obtained by the orthogonal wave imaging procedure from the value of the image signal based on the image data obtained by the parallel wave imaging procedure. The optical inspection method is characterized by being provided.

In this aspect, one of the procedure of polarizing the light irradiated to the pressure-bonded portion along one polarization axis, the dichotomy of dividing the light reflected by the pressure-bonded portion, and the dichotomized light is performed. A parallel-wave imaging procedure for imaging by polarization along a polarization axis parallel to the one polarization axis, and the other of the bisected light is polarized along a polarization axis orthogonal to the one polarization axis for imaging. Since the image data obtained by the parallel wave imaging procedure has a quadrature wave imaging procedure, the metal part becomes brighter and the resin part becomes darker in the image data obtained by the parallel wave imaging procedure, and the resin part appears in the image data obtained by the orthogonal wave imaging procedure. Is about the same as the brightness obtained by the parallel wave imaging procedure, while the metal part becomes dark. Further, an image analysis procedure for performing image analysis based on a value obtained by subtracting the value of the image signal based on the image data obtained by the orthogonal wave imaging procedure from the value of the image signal based on the image data obtained by the parallel wave imaging procedure. Since the brightness of the metal part of the finally obtained image data is the same as that of the image data obtained by the parallel wave imaging procedure, the resin part is affected by the color of the resin. Without any of the image data. As a result, the contrast between the metal portion and the resin portion is increased.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a conceptual diagram showing the configuration of an optical inspection device 10 for crimp terminals according to an embodiment of the present invention. Also,
FIG. 2 is a perspective view showing a configuration of a main part of the optical inspection device 10 for a crimp terminal according to the first embodiment of the present invention.

With reference to these drawings, an optical inspection device 10 for a crimp terminal according to the illustrated first embodiment includes an illuminating means 11 for illuminating a crimp portion 1a including a crimp terminal 1 to be inspected, and an illuminator. Image pickup means 1 for picking up an image of the crimped portion 1a
2, a determination unit 13 that determines whether the pressure-bonded portion 1a is good or bad based on the imaged image data, a polarizing plate 14 that transmits the light irradiated to the pressure-bonded portion 1a, and a light that is reflected by the pressure-bonded portion 1a. And a polarizing plate 15.

As the illuminating means 11, a general industrial illuminating device having no polarization such as a white light bulb is used, and the crimped portion 1a to be inspected can be illuminated to generate a highlight portion. Is configured.

The image pickup means 12 is means for picking up an image of the highlight portion of the pressure-bonded portion 1a and acquiring image data of the pressure-bonded portion 1a, and an electronic image pickup device such as an industrial TV monitor camera is used.

The discriminating means 13 is means for discriminating the quality of the pressure-bonded portion 1a based on the image data picked up by the image pickup means 12, and a logic operation device such as a general-purpose personal computer is generally used. This logical operation device includes a binarization processing unit 13a that performs binarization processing of image data on the imaged crimped portion 1a, and a standard that stores the binarized image data in a storage unit (not shown). It is provided with a pass / fail determination unit 13b that determines pass / fail of the crimped portion 1a by comparing with the data.

The polarizing plates 14 and 15 are provided between the illuminating means 11 and the image pickup means 12 in order to provide contrast so that the metal portion becomes bright and the resin portion becomes dark in the image obtained by the image pickup means 12. It is a polarizing glass plate material. Each of the polarizing plates 14 and 15 inherently has a polarization axis in a fixed direction, and transmits only light polarized in parallel with the polarization axis, while blocking light polarized in the direction perpendicular to the polarization axis. In the first embodiment, the polarizing plate 1 that transmits the light with which the pressure-bonded portion 1a is irradiated is transmitted.
4 and a polarizing plate 1 for transmitting the light reflected by the pressure-bonded portion 1a
5 and 5 are arranged in pairs, and the polarization axes of the polarizing plates 14 and 15 are set to be parallel to each other along the longitudinal direction of the crimp terminal 1. Therefore, the light emitted from the illuminating means 11 is polarized by the one polarizing plate 14, and a parallel wave 16 is generated along the vibration direction defined by the polarization axis of the polarizing plate 14, and the parallel wave 16 is The pressure-bonded portion 1a is irradiated. In addition, the parallel wave 16 is reflected by the pressure-bonded portion 1a, then passes through the other polarizing plate 15, and the imaging unit 1
It is configured to reach 2 and be imaged.

Next, the operation of the first embodiment will be described with reference to FIGS.

FIG. 3 is a graph showing the brightness of an image taken by the optical inspection device 10 for crimp terminals according to the first embodiment of the present invention, and FIG. 4 is a graph showing the luminance of the first embodiment of the present invention. It is a flowchart which shows the image analysis process of the optical inspection apparatus 10 of the said crimp terminal.

FIG. 5 is a plan view showing the window positions for performing the image analysis process to determine whether the crimp terminal is acceptable or unacceptable.

Referring to FIG. 3, the X axis represents the positional relationship in the longitudinal direction of the crimp terminal 1 imaged by the image pickup means 12, and the Y axis represents the respective positions in the longitudinal direction of the imaged crimp terminal 1. Represents the luminance at.

In the first embodiment, as described above, the parallel wave 16 is applied to the pressure-bonded portion 1a, and the parallel wave 16 is reflected by the pressure-bonded portion 1a and transmitted through the other polarizing plate 15. After that, it reaches the image pickup means 12 and is imaged. Since the polarization axes of the polarizing plates 14 and 15 are set to be parallel to each other, the amount of light applied to the metal portion of the pressure-bonded portion 1a even after the light has passed through the other polarizing plate 15. While reaching the imaging means 12 without subtracting
The light applied to the resin portion is diffusely reflected on the surface of the resin, and after passing through the other polarizing plate 15, the light reaches the image pickup means 12 in a reduced light amount. As a result, the image pickup means 1
In the image obtained by 2, the metal part is bright and the resin part is dark. As described above, in the image of the optical inspection device 10 for the crimp terminal according to the first embodiment, the metal portion is bright and the wire jacket 2b that is the resin portion is dark.

Next, the image analysis process in the first embodiment will be described with reference to FIG.

First, in step S1, the illumination means 1
The light emitted from No. 1 is polarized by one polarizing plate 14, and a parallel wave 16 is generated along the vibration direction defined by the polarization axis of this polarizing plate 14, and this parallel wave 16 is applied to the pressure-bonded portion 1a. To be done.

Next, in step S2, the parallel wave 16 is reflected by the pressure-bonded portion 1a, and then the other polarizing plate 1 is used.
5, and reaches the image pickup means 12 to be imaged. Here, since the polarization axes of both polarizing plates 14 and 15 are set to be parallel to each other, as described above, in the image obtained by the image pickup means 12, the metal portion is bright and the resin portion is dark.

In step S3, the image pickup means 1
The image data of the crimp terminal 1 obtained by 2 in which the metal part is bright and the resin part is dark is binarized by the discrimination means 13 in order to proceed with data processing.

Further, in step S4, the discrimination means 1
In 3, the quality of the crimp terminal 1 is determined by comparing the binarized image data with standard data stored in a storage unit (not shown). That is, the crimp shape inspection is performed by performing the labeling processing, and the core wire protrusion inspection and the crimping position shift inspection are performed by performing the area processing to determine whether the crimping terminal is acceptable or not.

Here, the labeling processing is a method of counting the number of blocks, which is a set of white or black pixels inside an area surrounded by a predetermined window on the analysis screen, and judging whether the block is good or bad. Further, the area processing is a method of counting the number of white or black pixels in the inside surrounded by a predetermined window on the analysis screen and determining whether the pixel size is good or bad.

Referring to FIG. 5, the crimp shape inspection by the labeling process will be described in detail as follows. That is, the core wire barrel 3 of the crimp terminal 1 is surrounded by the window A, and the bright line 3a of the illumination reflected on the core wire barrel 3 (white block: a portion of the core wire barrel 3 which is reflected in white is shown in FIG.
Is represented as a shaded area in). At this time, since the illumination is projected from the two right and left directions, if the crimp shape of the core barrel 3 is normal, two bright lines 3a are formed on each of the left and right core barrels 3, and a total of four bright lines 3a appear. The quality is judged by whether or not the bright line 3a of the book appears.

The core wire protrusion inspection by area processing is specifically as follows. That is, the windows B to E are provided on the left and right background portions outside the crimp terminal 1.
Is provided and it is counted whether or not white pixels therein are present. If normal, the background is dark, so that no white pixel exists in these windows B to E, but if the core line 2a enters this area, a white pixel is detected, so it is determined that the core line is protruding. .

Further, the crimping position shift inspection by the area treatment is specifically as follows. That is, the windows F and G are provided on the resin resin above and below the resin barrel 4,
Check for the presence of white pixels in it. If normal, the wire resin portion is dark, so that there is no white pixel in these windows F and G. However, when the core wire 2a enters this area, a white pixel is detected, and therefore, the white pixel is not displayed. It is determined that the crimping position is displaced.

Further, a window H is provided at the portion of the core wire 2a between the window F and the core wire barrel 3, and the number of white pixels therein is counted. Under normal conditions, since the core 2a is bright, there are a certain number of white pixels in these windows H, but if the wire resin portion enters this area, the number of white pixels will decrease, so It is determined that there is a displacement of the crimping position.

In this way, when it is determined that the difference from the standard data stored in the storage unit is within a certain permissible value after the quality of the crimp terminal 1 is determined, it is determined as a non-defective product. It is sent to the process (S5a). If it is determined that the value is out of the allowable range, the product is sent to the discharging step as a defective product (S5b).

As described above, in the first embodiment, the light emitted from the illuminating means 11 is used as the one polarizing plate 14
It is polarized by and reaches the pressure-bonded portion 1a along the vibration direction defined by the polarization axis of the polarizing plate 14. This light reaches the image pickup means 12 after being reflected by the pressure-bonded portion 1a and then transmitted through the other polarizing plate 15. Here, since the polarization axes of both the polarizing plates 14 and 15 are set to be parallel to each other, the light applied to the metal portion of the pressure-bonded portion 1a is transmitted even after passing through the other polarizing plate 15. While reaching the image pickup means 12 without reducing the amount of light, the light applied to the resin portion is diffusely reflected on the surface of the resin, and therefore, after passing through the other polarizing plate 15, the image is taken with the light amount reduced. Reach the means 12. As a result, in the image obtained by the image pickup means 12, the metal part is bright and the resin part is dark.

Next, the second embodiment of the present invention will be described in detail with reference to the accompanying drawings, but the description of the same configuration as the first embodiment will be omitted and different from the first embodiment. Only the components will be described.

FIG. 6 is a conceptual diagram showing the construction of an optical inspection device 10 for crimp terminals according to a second embodiment of the present invention.
FIG. 7: is a perspective view which shows the structure of the principal part of the optical inspection apparatus 10 of the crimp terminal which concerns on 2nd embodiment of this invention.

With reference to these drawings, an optical inspection device 10 for crimp terminals according to the second embodiment shown in the drawings has an illuminating means 11 for illuminating the crimped portion 1a to be inspected and an illuminated crimped portion 1a. The two-view lens barrel 17 that divides the reflected light into two and outputs the light, and the pair of image pickup means 1 that are arranged corresponding to the output side of the two-view lens barrel 17 and pick up images of the crimped portions 1a, respectively.
2a, 12b, a judging means 13 for judging the quality of the pressure-bonded portion 1a based on the image data picked up by the image pickup means 12a, 12b, a polarizing plate 14 on the illumination side, and polarizing plates 15a, 15b on the output side. Is equipped with.

The dual-view lens barrel 17 is for dividing the light reflected by the illuminated pressure-bonded portion 1a into two and outputting the split light. A plurality of prisms are combined with the dual-view lens barrel 17. It is configured such that two equivalent images of the illuminated crimped portion 1a can be obtained.

The pair of image pickup means 12a, 12b is an electronic image pickup device provided respectively for picking up two images of the pressure-bonded portion 1a obtained through the two-view lens barrel 17, and the two-view lens barrel 17 is provided. Are arranged respectively corresponding to the output side of.

The discriminating means 13 stores a binarization processing section 13a for binarizing the image data of the imaged pressure-bonded portion 1a, and the binarized image data in a storage section (not shown). In addition to the quality determination unit 13b that determines the quality of the crimped portion 1a by comparing with the standard data,
An analysis unit 13c for performing image analysis is provided.

The analyzing unit 13c transmits a polarizing plate 15b whose polarization axes are orthogonal to each other based on an image signal value based on image data output by transmitting the polarizing plate 15a whose polarization axis is parallel to the polarizing plate 14 on the illumination side. Then, the value of the image signal based on the output image data is subtracted, and the image analysis is performed based on the value of the difference.

The polarizing plate 14 on the illuminating side is disposed between the illuminating means 11 and each image pickup means 12, and is a pressure-bonded portion 1a.
It is used to polarize the light that is emitted to the. Further, the polarizing plates 15a and 15b on the output side are the two-view barrel 17
Are provided on the output side of each pair to form a pair and are used to polarize the light output to the corresponding image pickup means 12a and 12b.

The polarizing plates 15a and 15b are arranged on the output side with respect to the polarization axis of the polarizing plate 14 on the illumination side.
Since the polarization axis of a is set to be parallel and the polarization axis of the polarizing plate 15b is set to be orthogonal to each other, the image of the crimp terminal 1 bisected by the two-view barrel 17 corresponds to the corresponding imaging. When reaching the means 12a, 12b, in the image data obtained by one of the imaging means 12a,
The metal portion is bright and the resin portion is dark, and in the image data obtained by the other imaging means 12b, the metal portion is dark and the resin portion is as bright as the one imaging means 12a. ing.

Next, the operation of the second embodiment will be described with reference to FIGS.

FIG. 8 is a graph showing the brightness of an image taken by the optical inspection device 10 for crimp terminals according to the second embodiment of the present invention, and FIG. 9 shows the brightness of the image according to the second embodiment of the present invention. It is a flowchart which shows the image analysis process of the optical inspection apparatus 10 of the said crimp terminal.

In the second embodiment, as described above, the parallel wave 16 from the illuminating means 11 is applied to the pressure-bonded portion 1a, and the parallel wave 16 is reflected by the pressure-bonded portion 1a. It is divided into two by the field-of-view lens barrel 17,
Corresponding to the image pickup means 12a which is polarized by the output side polarizing plates 15a and 15b which are respectively provided on the output sides of
7B, the image is output to the image pickup means 12a on the side of the polarizing plate 15a whose polarization axes are set parallel to the polarization axis of the polarizing plate 14 on the illumination side. It shows the brightness. In this case, as shown in FIG. 6, the light radiated to the metal portion reaches the image pickup means 12a without reducing the light amount even after passing through the polarizing plate 15a, whereas the light radiated to the resin portion. Since the diffused light is diffusely reflected on the surface of the resin, after passing through the polarizing plate 15a, the light reaches the image pickup means 12a in a reduced light quantity. as a result,
In the image obtained by the image pickup means 12a, the metal part is bright and the resin part is dark.

On the other hand, FIG. 7B shows the polarizing plate 14 on the illumination side.
It shows the brightness of the image output to the image pickup means 12b on the side of the polarizing plate 15b in which the polarization axes are set to be orthogonal to each other. In this case, as shown in FIG. 6, the light irradiated to the metal part is transmitted through the polarizing plate 15b and then reduced in quantity to reach the image pickup means 12b, whereas the light irradiated to the resin part is reduced. Diffusely reflects on the surface of the resin, and after passing through the polarizing plate 15b, reaches the image pickup means 12b in a state where a part of the light amount passes therethrough, and the image pickup means 12b.
In the image obtained by the method, the metal portion becomes darker and the resin portion becomes as bright as the one image pickup means 12a. Then, FIG. 7C shows a polarizing plate 15a having a polarization axis parallel to the polarizing plate 14 on the illumination side in the analyzing section 13c.
Is subtracted from the value of the image signal based on the image data output by transmitting the image data based on the image data output by passing through the polarizing plate 15b whose polarization axes are orthogonal to each other. 2 shows the brightness of the image analyzed. In this case, in the image obtained by the calculation of the analysis unit 13c, the brightness of the metal portion is the same as the image data obtained by the one image pickup means 12a, while the resin portion is not affected by the color of the resin. It is darker than any image data without being received. As a result, the contrast between the metal portion and the resin portion is increased.

Thus, the image data obtained by the optical inspection device 10 for crimp terminals according to the second embodiment is
The electric wire jacket 2b, which is a resin portion, is imaged more darkly than the crimp terminal 1 which is a metal portion and the core wire 2a.

Next, the image analysis process in the second embodiment will be described with reference to FIG.

In step S11, the light emitted from the illumination means 11 is polarized by the one polarizing plate 14,
A parallel wave 16 is generated along the vibration direction defined by the polarization axis of the polarizing plate, and the parallel wave 16 is applied to the pressure-bonded portion 1a.

Next, in step S12a, the parallel wave 16 is reflected by the pressure-bonded portion 1a, transmitted through the polarizing plate 15a, and then reaches the image pickup means 12a to be imaged. Here, since the polarization axes of both polarizing plates 14 and 15a are set to be parallel to each other, as described above, in the image obtained by the image pickup means 12a, the metal portion is bright and the resin portion is dark.

In step S12b, the parallel wave 16 is reflected by the pressure-bonded portion 1a, and then the other polarizing plate 1
After passing through 5b, it reaches the imaging means 12b and is imaged. Here, since the polarization axes of both the polarizing plates 14 and 15b are set to be orthogonal to each other, as described above, in the image obtained by the image pickup means 12b, the metal portion becomes dark and the resin portion becomes one. The same brightness as that of the image pickup means 12a.

Further, in step S13, an inter-image calculation (subtraction) process is performed in the analysis section 13c, and as described above, the brightness of the metal part is determined by the image pickup means 12a of one side.
Although it is not different from the image data obtained by, the resin part is not affected by the color of the resin,
It becomes darker than any image data. As a result, the contrast between the metal portion and the resin portion is increased.

The steps after the binarization process in step S14 are the same as those in the first embodiment.

As described above, in the second embodiment, the light emitted from the illuminating means 11 causes the light on the illuminating side of the polarizing plate 1 to be illuminated.
The light is polarized by 4 and becomes light along the vibration direction defined by the polarization axis of the polarizing plate 14 and reaches the pressure-bonded portion 1a. This light is reflected by the pressure-bonded portion 1a, is divided into two, passes through the corresponding polarizing plates 15a, 15b, and then reaches the corresponding imaging means 12a, 12b. Here, the polarization axis of one polarization plate 15a is set parallel to the polarization axis of the polarization plate 14 on the illumination side, and the polarization axis of the other polarization plate 15b is set to be orthogonal to each other. In the image data obtained by one of the image pickup means 12a, the metal portion becomes bright and the resin portion becomes dark, and in the image data obtained by the other image pickup means 12b, the metal portion becomes dark and the resin portion becomes one. The brightness is about the same as that of the image pickup means 12a. Further, the analyzing unit 13c of the discriminating means 13 in the present invention is
Based on the image data output from the image signal value based on the image data output through the polarizing plate 15a whose polarization axis is parallel to the polarizing plate 14 on the illumination side, based on the image data output through the polarizing plate 15b whose polarization axis is orthogonal. Since the image analysis is performed based on the value obtained by subtracting the value of the image signal, the brightness of the metal portion of the finally obtained image data is the same as the image data obtained by the one image pickup means 12a. The resin portion is darker than any image data without being affected by the color of the resin. As a result, the contrast between the metal portion and the resin portion is increased.

The above-described embodiment is merely an example of a preferred specific example of the present invention, and the present invention is not limited to the above-described embodiment.

For example, the polarization axis of the polarizing plate 14 on the illumination side is
It does not necessarily have to be along the longitudinal direction of the crimp terminal 1.

Next, the illuminating means 11 does not necessarily have to be a white light bulb, and other illuminating means such as illumination by a light emitting element can be used.

Further, the polarizing plates 14, 15, 15a, 15b
Does not necessarily have to be a polarizing glass plate material, but may be a polarizing resin plate material.

Needless to say, various design changes can be made within the scope of the claims of the present invention.

[0067]

As described above, according to the present invention,
The metal part is bright, and the resin part is not affected by the color of the resin, and the image is processed with contrast so that it becomes dark.
Alternatively, the crimp portion of the crimp terminal can be inspected in a more multifaceted manner such as the quality of the crimp shape.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a configuration of an optical inspection device for crimp terminals according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a main part of the optical inspection device for a crimp terminal according to the first embodiment of the present invention.

FIG. 3 is a graph showing the brightness of an image captured by the optical inspection device for crimp terminals according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing an image analysis process of the optical inspection device for crimp terminals according to the first embodiment of the present invention.

FIG. 5 is a plan view showing a window position for performing a pass / fail judgment of a crimp terminal by performing an image analysis process.

FIG. 6 is a conceptual diagram showing a configuration of an optical inspection device for crimp terminals according to a second embodiment of the present invention.

FIG. 7 is a perspective view showing a configuration of a main part of an optical inspection device for a crimp terminal according to a second embodiment of the present invention.

FIG. 8 is a graph showing the brightness of an image captured by the optical inspection device for crimp terminals according to the second embodiment of the present invention.

FIG. 9 is a flowchart showing an image analysis process of the optical inspection device for crimp terminals according to the second embodiment of the present invention.

[Explanation of symbols]

1 Crimp terminal 1a Crimped part 10 Optical inspection device for crimp terminals 11 Lighting means 12, 12a, 12b Imaging means 13 Discrimination means 13c analysis section 14 Polarizer 15, 15a, 15b Polarizing plate 17 Two-view barrel

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2F065 AA23 AA53 AA58 BB06 DD09                       FF04 FF49 GG02 LL33 LL34                       LL46 PP22 QQ04 QQ25 RR02                       SS04 UU05 UU07

Claims (4)

[Claims] 1. An illuminating means for illuminating a crimp portion including a crimp terminal to be inspected, an image pickup means for picking up an image of the illuminated crimp portion, and a judgment for judging whether the crimp portion is good or bad based on the picked-up image data. A polarizing plate that transmits the light irradiated to the pressure-bonded portion and a polarizing plate that transmits the light reflected by the pressure-bonded portion are arranged in pairs between the illumination means and the imaging means. In the optical inspection device, the polarization axes of the polarizing plates are set to be parallel to each other. 2. An illuminating means for illuminating a crimping portion including a crimping terminal to be inspected, a two-view lens barrel for splitting and outputting light reflected by the illuminated crimping portion, and an output side of the two-view lens barrel. The optical inspection device includes a pair of image pickup units arranged corresponding to each of the pressure-bonded portions, and a determination unit that determines whether the pressure-bonded portion is good or bad based on the image data captured by each image pickup unit. A polarizing plate on the illumination side, which is disposed between the illumination means and each imaging means, and which polarizes the light irradiated to the pressure-bonded portion, and which is provided on each of the output sides of the two-view lens barrel to form a pair, A polarizing plate on the output side that polarizes the light output to the corresponding image pickup means is provided, and one of the polarizing axes of the polarizing plate on the output side is set parallel to the polarizing axis of the polarizing plate on the illumination side. Set either of them in the orthogonal direction and As another means, image data output through a polarizing plate whose polarization axis is orthogonal to the image signal value based on the image data output by transmitting a polarizing plate whose polarization axis is parallel to the polarizing plate on the illumination side. An optical inspection apparatus comprising an analysis unit for performing image analysis based on a value obtained by subtracting the value of an image signal based on the above. 3. An optical inspection method for illuminating a crimp portion including a crimp terminal to be inspected, imaging the illuminated crimp portion, and determining whether the crimp portion is good or bad based on the imaged image data. The procedure of polarizing the light applied to the pressure-bonded portion along one polarization axis and the procedure of imaging the light reflected by the pressure-bonded portion along the polarization axis parallel to the one polarization axis are described. An optical inspection method characterized by being provided. 4. An optical inspection method for illuminating a crimped portion including a crimp terminal to be inspected, imaging the illuminated crimped portion, and determining whether the crimped portion is good or bad based on the imaged image data. The procedure to polarize the light irradiated to the pressure-bonded part along one polarization axis, the two-way procedure to divide the light reflected from the above-mentioned pressure-bonded part into two, and one of the two divided light is parallel to the one polarization axis. A parallel-wave imaging procedure for imaging by polarization along a polarization axis, and a orthogonal-wave imaging procedure for imaging the other of the bisected light by polarization along a polarization axis orthogonal to the one polarization axis, An image analysis procedure for performing image analysis based on a value obtained by subtracting the value of the image signal based on the image data obtained by the orthogonal wave imaging procedure from the value of the image signal based on the image data obtained by the parallel wave imaging procedure That Optical inspection method according to symptoms.