JPH07146178A - Hue switching judgment method of sheathed wire - Google Patents

Abstract

PURPOSE:To objectively, accurately, and rapidly judge the timing when a sheathed wire changes from one initial hue which is determined by a standard color sample and a timing when it changes to a final hue. CONSTITUTION:Each color signal of R, G, and B is taken out by picking up the image of the inside of a certain region including a colored sheathed wire 2, the histogram of the brightness distribution of R. G, and B is created based on these color signals, and then the maximum brightness values HR, HG, and HB of each histogram are detected. On the other hand, a hue allowable range for each of R, G, and B corresponding each standard color sample is preset, the maximum brightness values HR, HG, and HB measured for the sheathed wire 2 are compared with the hue allowable range corresponding to two color samples after the preset hue switching, and then it is judged that the hue of the sheathed wire 2 is being switched when the maximum brightness values HR, HG, and HB are from the timing deviated from one hue allowable range to the timing shifted into the other hue allowable range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coated wire having a colored coating formed on its surface for insulation or protection, and the coated wire is changed from one hue defined as a standard color to the other hue. The present invention relates to a hue switching determination method for determining a time point at which complete switching is performed.

[0002]

2. Description of the Related Art Generally, a core wire forming each cable of an electric wire or an optical fiber has a coating film formed on its surface for insulation or protection, and each coating wire can be easily identified. Wearing various colors to make.

That is, when connecting cables to each other, connecting cables to various devices, etc., it is essential to identify each core wire in order to prevent erroneous wiring. Therefore, the surface of the core wire must be identified. A colorant such as a pigment is mixed in the formed film for coloring.

By the way, in the case of producing multi-layered wires having various hues, the colorants are exchanged or the mixing ratio of the colorant is changed so that the multi-layered wires of the desired hue can be obtained. When replacing the colorant, the colorant before replacement may remain in the manufacturing equipment of the multi-tracked wire a little.Therefore, until the hue is completely switched, the hue along the longitudinal direction of the multi-tracked wire is changed. Will change continuously. Then, since the portion where the hue changes continuously becomes an intermediate color different from the hue of the standard color sample before and after the switching, such a covered wire cannot be used and must be removed as a defective product. For that purpose, it is necessary to monitor, in the production line, the time when the line to be covered is out of one hue and the time when the line to be covered is completely switched to the other hue.

Conventionally, in order to determine when the covered wire deviates from one hue before switching and when it completely switches to the other hue, a standard color sample is referred to, and this color sample and manufacturing The color of the coated wire is directly compared by visual observation.

However, in visual comparison observation,
The objectivity is poor and individual differences tend to occur, and even when the same person judges, the hue is different because the surrounding brightness and the core speed at the time of manufacturing are as high as about 3000 m / min. It may be visible and the judgment may be incorrect.

On the other hand, the prior art also provides a hue determination device capable of automatically determining the hue.

However, the conventional ones are limited to those which judge the hue of a plate-like object having a considerably wide color area (around several cm ² ). Therefore, even with this device,
It is difficult to accurately and quickly determine the hue of the core wire produced at a high speed (about 3000 m / min) and attached to an extremely thin area (for example, a diameter of about 0.45 to 0.9 mm).

[0009]

Therefore, the inventors of the present invention set an image of a certain area including a covered line as a still image, and
After obtaining each color signal of R, G, B and creating a histogram for each color signal of these R, G, B, the maximum brightness value H of the histogram of each color signal of these R, G, B
We proposed a method for determining the hue of the coated wire by detecting R, HG, and HB (Japanese Patent Application No. 4-30).
6908).

According to this method, it is possible to confirm and judge the hue itself applied to the thin coated wire such as the cable core wire.

However, this method cannot accurately detect the situation where the hue of the covered wire flowing at high speed is changing.

The present invention has been made in order to solve such a problem in the related art, and in a situation where a thin coated wire such as a cable core wire is drawn out at a high speed in a manufacturing line, An object of the present invention is to make it possible to objectively, reliably, and swiftly judge a time when a hue defined by a standard color sample starts to be changed and a time when the hue is completely changed to the other hue, without any manual operation.

[0013]

The present invention adopts the following constitution in order to solve the above problems.

That is, in the hue switching judging method for the covered wire according to the present invention, the black screen is used as a background, and the illuminance on the surface of the covered wire is constant or the same as the natural light so as to be constant. The light having the above-mentioned spectral distribution is irradiated, a fixed region including the covered line irradiated with the light is imaged to make a still image, and R, G, B color signals are extracted, and these R, G, B are extracted. After creating histograms of these R, G, and B lightness distributions based on the respective color signals of, the maximum lightness values HR and H of each histogram are created.
G, HB are detected, and for each standard color sample, a hue tolerance range for each R, G, B corresponding to each color sample is set in advance, and the maximum lightness value HR, which is measured for the covered line, HG and HB are respectively compared with a hue allowable range corresponding to two preset color samples before and after hue switching, and any one of the maximum lightness values HR, HG, and HB is either one of the hue allowable ranges. It is determined that the hue of the double line is in the middle of switching when it is between the time point when the hue deviates from the above range and the time point when the color shifts to the other hue allowable range later.

[0015]

In the above construction, the maximum brightness values HR, HG, HB are determined by creating a histogram of R, G, B based on the reflected light from the covered wire. Then, the maximum lightness values HR, HG, and HB are compared with the hue allowable range for each of R, G, and B corresponding to two predetermined color samples, and it is determined whether or not there is a hue change. It is possible to objectively, accurately, and swiftly determine a hue change point attached to a line.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an apparatus used for a method for determining a hue switching of a covered wire according to an embodiment of the present invention.

In this example, the apparatus 1 is installed on the production line of the colored covered wire 2, and a case 3 for removing dust in the factory is provided on the production line. The covered wire 2 penetrates through.

In the case 3, for the covered wire 2,
Lamps 4a and 4b for irradiating light having a spectral distribution identical to or close to natural light so that the illuminance on the surface is constant (500 to 1500 lux, preferably 900 lux) are provided, and the covered wire is also provided. A black screen 5 is attached to the back surface of 2 in order to prevent the influence of the background from appearing in the data.

Further, in the case 3, an image of a certain area irradiated with light from the lamps 4a and 4b is imaged at a position facing the covered wire 2 and the screen 5, and based on the reflected light in the imaged area. A video camera 6 is provided as an image pickup means for extracting R, G, B color signals.

Reference numeral 8 is an image monitor for displaying an image picked up by the video camera 6, 10 is R from the video camera 6,
Data processing means for determining the hue of the coating film of the coated wire 2 based on the G and B color signals, 11 is the data processing means 1
Input means for setting and inputting data to 0, which is composed of, for example, a keyboard or a mouse. An output unit 12 outputs the result of the data processing unit 10, and is composed of, for example, a display or a printer.

The data processing means 10 includes a histogram creating means 14, a maximum brightness detecting means 16 and a hue switching judging means 20.

The histogram creating means 14 uses the R, G, and B color signals obtained by the video camera 8 to generate R, G, and B color signals.
A histogram of the lightness distribution of each color of G and B is created, and the maximum lightness detection means 16 uses R, G, B of each histogram created by the histogram creation means 14.
The maximum lightness values HR, HG, and HB of each hue are detected. Further, the hue switching determination means 20 compares the maximum lightness values HR, HG, HB measured for the covered wire with a preset hue allowable range corresponding to the two color samples before and after the hue switching, and the maximum lightness. When any one of the values HR, HG, and HB is between the time when the hue is out of the hue tolerance range for one of the color samples and the time when it is subsequently shifted to the hue tolerance range for the other color sample, It is configured to determine that the hue of the double line is being switched.

Next, a method of determining the hue change of the covered wire 2 using the above device 1 will be described.

First, the illuminance on and around the surface of the covered wire 2 passing through the case 3 is constant (for example, 500 to 15).
Natural light is emitted by the lamps 4a and 4b so that the light intensity is 00 lux, preferably around 900 lux. And. Reflected light in a certain area including the covered wire 2 irradiated with natural light is captured by the video camera 6 and captured as a still image.

In response to this image pickup, R, G, and B color signals are obtained as the output of the video camera 6.
The G and B color signals are loaded into the data processing means 10.

The histogram creating means 14 creates a histogram of the lightness distribution for each of the R, G and B color signals.

The histogram data for these color samples is sent to the maximum brightness value detecting means 16 in the next stage, so that the maximum brightness value detecting means 16 uses R, G, B.
Brightness values HR, H of the histogram for the color signal of
G and HB are detected.

Then, these maximum brightness values HR, HG,
Since each HB data is sent to the next-stage hue switching determination means 20, the hue switching determination means 20 determines the hue switching of the covered wire 2 according to the flowchart shown in FIG.

That is, prior to the determination of the hue change of the covered wire 2, the R,
As shown in Table 1, data of maximum brightness HR, HG, HB of G and B is collected, and in consideration of variations in measurement centered on maximum brightness values HR, HG, HB, as shown in Table 1, Regarding the hue, the hue allowable ranges HRmax and HRmin, HGmax and HGmin, HBmax and HBmin are set respectively.

[0030]

[Table 1]

For example, if the initial hue before switching is blue, HRmax = 68, HRmin = 55, HGmax =
130, HGmin = 100, HBmax = 180, HBmin
= 165, and if the final hue after switching is green, HRmax = 92, HRmin = 75, HGmax = 1
57, HGmin = 140, HBmax = 113, HBmin =
It becomes 100. Then, the data of the hue allowable range is input from the input means 11 and registered in the hue switching determination means 20 in advance.

As described above, with respect to the covered wire 2, the maximum brightness value detecting means 16 described above causes the maximum brightness values HR,
If HG and HB are obtained, the hue switching determination means 20
Compares each of these maximum lightness values HR, HG, and HB with a hue allowable range corresponding to one preset color sample after the hue switching, and the maximum lightness values HR, HG, and HB show the hue allowable values. It is determined that the hue of the double line is switched at the time when the hue is out of the range and when the hue shifts to the hue allowable range of the final color.

For example, when the initial hue is changed from "blue" to the final hue is "green", the hue allowable range of "blue" before the change is HRmax as shown in FIG. 2 (a).
= 68, HGmax = 130, HBmax = 180, and a triangle formed by connecting the solid lines, and HRmin = 55, HGmin =
As shown in FIG. 2B, the hue allowable range of “green” after switching is within a range surrounded by a triangle formed by connecting each value of 100 and HBmin = 165 with a solid line. , HRmax = 92, HGmax = 157, HBmax = 11
A triangle formed by connecting each value of 3 with a solid line, and HRmin = 7
5, HGmin = 140 and HBmin = 100 are within the range surrounded by the triangle formed by connecting the solid lines. And even one of the maximum brightness values HR, HG, HB is shown in FIG.
The period from the time when the hue is out of the permissible range to the time when the hue is completely within the permissible hue shown in FIG.
It is determined that “blue” is switching to “green”.

If it is determined that even one of the maximum brightness values HR, HG and HB is out of the hue allowable range and the hue is being switched, the lamp is turned on, for example. Further, when all the maximum brightness values HR, HG, HB shift to within the final hue allowable range, for example, a beep sound is output. Further, each of these determination results is output by the output means 12.

Thus, the three maximum brightness values H are always
Since the hue change is determined by comparing R, HG, and HB with the hue allowable range determined based on the standard color sample, it is possible to objectively, accurately, and quickly determine whether the hue of the covered wire 2 is changed. can do.

Although a pair of lamps 4a and 4b are used as the light source in the above embodiment, as shown in FIG. 4, a single light source 4 is connected to a bifurcated bundle fiber 9a and 9b.
It is also possible to adopt a configuration in which the wire is drawn toward the double-tracked wire 2.

[0037]

According to the present invention, an image captured from a camera is used as a still image, and R, R is calculated based on the reflected light from the covered wire.
G and B histograms are created and maximum brightness values HR and H
G, HB are determined, and maximum brightness values HR, HG, H of these are determined.
Since B is compared with the hue allowable range for each R, G, and B corresponding to each standard color sample, the change of hue is determined, so compared with the conventional visual determination, There is no difference, and it is not affected by the brightness of the surroundings or the high speed of 3000 m / min of the coated wire at the time of manufacturing. Therefore, even with a thin coated wire such as a cable core wire having a coating formed on its surface for insulation or protection, it is possible to objectively, accurately, and swiftly determine the time at which the hue changes. In particular, since it is possible to determine in the covered wire manufacturing line whether the hues of the same system color are gradually changing, it is possible to effectively use them in terms of quality control.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an apparatus used in a hue switching determination method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a hue allowable range that is determined based on a standard color sample used for hue switching color removal determination of the same apparatus.

FIG. 3 is a flowchart of a hue switching determination process in the data processing unit of the same device. In this case, hue switching from blue to green is taken as an example.

FIG. 4 is a front view showing a modified example of a portion of a device used for a hue switching determination method according to an embodiment of the present invention, in particular, a light irradiation portion on a covered wire.

[Explanation of symbols]

1 ... Device used for determining hue change color of covered wire, 2
... Covered wire, 4a, 4b ... Light source (lamp), 6 ... Imaging means (video camera), 9a, 9b ... Bundle fiber, 14 ... Histogram creating means, 16 ... Maximum brightness value detecting means, 20
... Hue switching determination means.

Claims (1)

[Claims] 1. A black screen is used as a background to irradiate a colored coating line with light having a spectral distribution identical to or close to that of natural light so that the illuminance on the surface is constant. An image is taken within a certain area including the irradiated covered line, R, G, B color signals are extracted from this still image, and these R, G, B color signals are extracted based on these R, G, B color signals. After creating the histogram of the brightness distribution of each, the maximum brightness value HR, H of each histogram
While G and HB are detected, for each standard color sample, the allowable hue range for each R, G, B corresponding to each color sample is set in advance, and the maximum brightness value HR measured for the covered line is set. , HG,
HB is compared with the hue tolerances corresponding to two preset color samples before and after the hue change, and any one of the maximum brightness values HR, HG, HB is out of the hue tolerance range of one. A hue switching determination method for a covered wire, comprising: determining that the hue of the covered wire is in the process of being switched during a period from the point of time when all of the hues have shifted to the other hue allowable range.