JPH0633367A - Method for examining color difference of sheet-like article - Google Patents

Abstract

PURPOSE:To efficiently examine the difference of colors by collectively controlling the various functions of color difference-examining devices with plural CPUs and subsequently graphing and printing out the measured data when either of the finish of the examination of the sheet-like article in a prescribed length and the detection of a pieced section is satisfied. CONSTITUTION:In the examination of the color difference of a sheet-like article such as woven or knitted fabric, nonwoven fabric or film, an examination condition-inputting member 6, the first display 2, the first output member 3, the color-measuring system using color sensors 10, a sensor 17 for detecting a pieced section 16, and a transferring system are collectively controlled with the first CPU 1, and the measured color data are treated with the second CPU 7 connected to the first CPU 1 through a communication line so as to enable the displaying and printing-out of the data. When either of the finish of the examination of the sheet-like article 15 in a prescribed length and the detection of the pieced section 16 is satisfied in the process for measuring the color of the sheet-like article 15 transferred in a belt-like state, the transfer of the sheet-like article is stopped, and the measured data of the color differences and their variations are graphed on the second display 8 and simultaneously printed out with the second output member 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting a color difference of an object, and more particularly, a method for inspecting a color difference of a sheet-like material such as a woven fabric, a knit fabric, a non-woven fabric or a film mainly using a color sensor. Regarding

[0002]

2. Description of the Related Art Generally, in the process of dyeing industrial products such as cloths, films and plates, for example, woolen fabrics or cotton fabrics, color unevenness may occur due to uneven distribution of dyes, or partial coloring due to overheating or inclusion of foreign matter may occur. Or stains that turn brown due to oil or the like. Such color unevenness, stains, etc. occur locally and suddenly, and are considered to be fatal defects in the appearance of industrial products.Therefore, inspectors always visually inspect all products and all of them. It is the current situation. Therefore, the labor required for the inspection is large, and in order to rationalize the labor, the following inspection methods have been conventionally known. (1) Scanning the light flux of the laser beam at a high speed in a direction perpendicular to the product (measurement object) conveyance direction, and focusing on the point that the reflectance of the abnormal part changes with respect to the normal part, to detect scratches etc. To do. (2) A television camera using an image sensor scans the surface of the product, extracts an image signal and processes it to obtain a color unevenness signal. (3) A photoelectric colorimeter (color sensor) or a spectrophotometer is arranged above or below a product conveyed at a required speed,
The surface color of an object is continuously measured.

[0003]

However, in the above-mentioned conventional inspection method, although it is possible to attain a purpose for a condition corresponding to the principle, it is possible to check the color difference of the sheet-like object online. Is difficult to achieve a sufficient effect in terms of inspection efficiency. That is, in the method using the luminous flux of the laser beam, since the laser beam is monochromatic light, it is possible to detect scratches that scatter the light and adhesion of foreign matter, but it is not possible to detect a color difference. In addition, the method using an image sensor requires an image analysis device and requires data processing by software, which increases the time required for detection and increases the equipment cost, and TV cameras have a poor color discrimination performance. It is not enough to perform inspections comparable to the human eye, and it is also not possible to meet the required speed of the process. Further, regarding the method using the color sensor or the spectrophotometer, many methods and devices have been proposed,
In the case of woven fabrics with many hue types, it is often the case that the inspection length is known in advance, it is unknown, or the length is not constant, so it is necessary to adjust the inspection length setting for each inspection. It was Therefore, if the seam can be detected automatically, it does not take extra time. However, even if you want to inspect only about 10 m from the top of the fabric, the inspection does not end until all the lengths are inspected and the seam is detected. Happens. In the past, no disclosure has been found regarding the point of improving the efficiency of the color difference inspection of the sheet material.

[0004]

In order to solve the above-mentioned problems, the present invention is an apparatus for inspecting on-line the color unevenness etc. of a sheet-like object such as a woven fabric or a film conveyed at a required speed. A transport unit that allows the sheet-like object to travel in a strip shape, an input unit that inputs the inspection conditions etc, a first display unit that displays the inspection conditions, a first output unit that outputs the results, and these transport units, input units, and the first A plurality of color sensors provided with a first CPU for controlling the display unit, the first output unit, and the joint detection unit, and positioned above or below the sheet-like material, and connected to the color sensors, and communicate with the first CPU A second display unit for processing the color measurement and the read data of the color sensor controlled by the second CPU connected by the line to detect and display the color difference of the sheet-like material, and outputting the result. Like the second output It is a color difference inspection device that is configured, whether the inspection of the set length is completed or whether the seam detection signal is received, whichever comes first, whichever satisfies the conditions is terminated first, and The result and the color difference variation graph are output.

Whether the inspection length of the sheet material is known or unknown, the necessary and sufficient inspection up to the required length can be performed, and the control system using a plurality of CPUs is used.
The transport system, input of inspection conditions, real-time screen display, output of results, etc. can be easily controlled, information desired to be inspected can be instantly obtained, and inspection efficiency is remarkably improved. An embodiment of the present invention will be described below with reference to FIGS.
This will be described with reference to FIG.

FIG. 1 shows a general inspection procedure in an online color difference inspection when a color sensor is used.
It is a ral Flow Chart. That is, the conditions such as the product name of the object to be measured, the inspection date, the inspection speed, etc. are input, and the reference value for performing the color difference inspection, that is, the reference color value is set. The power of the transport system is turned on and the measurement is started. In the measurement of the color sensor, data is collected at certain fixed time intervals, so that the inspection can be performed while identifying the measurement points. If it is a measuring point, the color is measured to collect data and display it on the screen. When the measurement end point comes, the power of the conveying system is turned off, the results are totaled, and the necessary color difference variation graph is printed out.

FIG. 2 shows a basic system configuration block diagram for applying the above procedure to a color difference inspection apparatus for a sheet material to improve the inspection efficiency. First, this system has a plurality of CPUs. (1st CPU and 2nd CPU) 1st
As a (peripheral) device connected to the CPU, there is a conveyance section (driving section), which includes a conveyance motor for moving a sheet-like object, drive motors for focusing a color sensor on a colorimetric position, and meandering prevention. It includes mechanical devices such as wrinkle straightening and tension control (neither shown). Next, there is an input unit, which is a device for inputting inspection conditions (for example, product name, inspection speed, inspection length, etc.), such as keyboard, bar code reader, voice input device, start / stop / advance / forward of transport system. It is composed of a switch input device for instructing reverse and the like. Furthermore, the first display unit (CR) for constantly monitoring the inspection conditions before / after / after the inspection
T), a first output unit (printer) that prints out inspection conditions and results, and a detection unit that detects a joint between sheet-like objects. As a device connected to the second CPU, in order to perform color difference inspection of a plurality of color sensors, especially sheet-like objects, it is desired to intensively check the color difference between the center and both sides to detect the presence or absence of color unevenness. The most efficient arrangement method is to install three color sensors vertically to the. Next, it is easy to directly connect an input device (not shown) to the second CPU, but a communication line is connected to the second CPU between the first CPU and the input unit connected to the first CPU. Since the input condition can be transmitted to the second CPU, the input device is unknown to the second CPU. Further, it is important for the inspection to know the variation of the color difference in real time during the inspection. Therefore, the data obtained by successive color measurement is displayed in a graph.
It has a display unit (graphic display). It can be said that the most efficient inspection device configuration is that the graph etc displayed on the screen is printed out at the same time when the measurement is completed.

FIG. 3 shows a conceptual diagram of the system configuration of the present invention, and the block diagram will be described in more detail. 1st CP
The U, the first display unit, the first output unit, and the like are configured by, for example, a personal computer PC-9801 (manufactured by NEC). The first CPU is provided with a built-in storage device of about 100 MB (megabytes), and is configured to record inspection conditions, data and the like. Also, an input / output interface board and an A / D conversion board are connected to the input / output (I / O) terminals of the first CPU to control the transport system (driving motor), switch input signals, and joint detection signals. There is. Further, in order to use a plurality of color sensors, it is necessary to calibrate each color sensor, and there are absolute value calibration (white plate calibration) and reference color calibration according to an object to be measured. In order to do this efficiently, the calibration plate installed in the linear motor is automatically moved to the position of each color sensor. The control of this linear motor is also the first
The CPU (PC-9801) is in charge. The input unit is composed of an inspection condition input device such as a keyboard and a bar code reader, and a switch input device for controlling start / stop / forward / reverse command of the transport system. The seam detection unit is composed of a sensor (for example, a photoelectric switch, a linear sensor camera, an area sensor camera, etc.) that detects a seam of a sheet-like object, and a detection device (for example, an image processing device) that processes a signal detected by the sensor. It becomes.
Next, the second CPU controls color measurement by a plurality of color sensors, processes the data obtained by the color measurement, and displays the color difference variation graph on the second display unit (graphic display) in real time. There is. For this reason, it is necessary to perform color measurement (three color sensors) and data display (three colors) simultaneously and sequentially. Therefore, the second CPU configuration is well-known in the computer field, for example, OS9 which can perform multi-task processing. A 68020 (Motorola) processor system based on (operating system) is used. The first output unit prints out inspection conditions and detailed numerically analyzed data as necessary.
The second output unit prints out the color difference variation graph displayed on the second display unit when the measurement is completed. The first CPU and the second CPU are, for example, RS23
It is connected by a 2C communication line, and transmission of inspection conditions, colorimetric commands, and the like (first CPU → second CPU), transmission of data obtained by a color sensor (second CPU → first CPU), and the like are performed bidirectionally. Further, the second CPU and the three color sensors are also connected by the RS232C communication line, and the command data and the like are bidirectionally transmitted. Since it is configured as described above, even if it has a lot of hues and uneven lengths such as woven fabric, it is possible to set the inspection length or detect the seam so that the color difference inspection of the sheet This is a device that can be performed online more quickly and can improve inspection efficiency by performing color measurement and data display in real time.

Next, the function of the present invention will be described with reference to the flow charts of FIGS. Note that C and D in the flowchart of FIG. 4 are connected to C and D of FIG. In the flowcharts of FIGS. 4 and 5, the operations on the first CPU side (for example, PC-9801 control side) and the second CPU side (for example, 68020 control side) are shown separately. 1st C
Since the PU and the second CPU are connected by the RS232C communication line, it is defined that the condition command and data at that time are transmitted from the first CPU side or the second CPU side in the flowchart in the direction of the dotted arrow. Explaining the first CPU side, when the power is turned on, the initial state is set and the inspection condition etc is input. In order to eliminate erroneous input, the barcode is input as much as possible, and the inspection date and inspection time are automatically set by the first CPU. Further, it is efficient to input a predetermined value as the inspection speed and input the set speed only when necessary. If all of these conditions are set, the conditions set by the first CPU are transmitted to the second CPU. Next, check whether to perform white calibration. This is to calibrate the absolute value of the colorimetric value of the color sensor, which is a necessary operation for what is called the current color sensor. As a general rule, it should be done before color measurement as much as possible, but in normal use, calibration several times a day is sufficient. This white calibration plate is fixed to the linear motor as shown in FIG.
All you have to do is move to the position. Similarly, the reference color calibration is necessary to reduce the inter-device error of each color sensor so that a plurality of color sensors show the same colorimetric value when the same object is colorimetrically measured. This operation is not mentioned here because there is an optimum calibration method depending on the color sensor used. (For example, JP-A-62-14
Therefore, here, the operation for eliminating (strictly minimizing) the inter-device error of a plurality of color sensors is defined as the reference color calibration. The standard color calibration is
The colorimetric value obtained at this time is stored in the storage device as the reference color value because the reference sample is measured as the measurement object. If the reference color calibration has already been performed, the corresponding data is retrieved from the storage device and set. Here, CIE Lab color system (1976)
Is used to indicate the reference color value by (L0 * a0 * b0 *).
On the side of the first CPU, selection is made as to whether the reference color value is set by the reference color calibration or the data retrieval from the storage device. Finally, when the reference color value setting confirmation signal is output from the second CPU side, the condition setting up to the color measurement on the first CPU side is completed. After confirming that there is no abnormality in the transport system or peripheral equipment, when the inspection start signal is input by the switch, the transport system motor turns on and the sheet-like object enters the running state, and at the same time the color measurement starts on the second CPU side. Command is transmitted. While the color sensor is actually measuring the color, the first CP
The operation on the U side is mainly to check the abnormal signal detection of the transport system,
Check the seam detection signal of the sheet-like object or use the second CPU
The colorimetric data sent from the device is received, and the data is stored in the storage device. When an abnormal signal is detected, the transportation system is stopped and stands by. If not, check if the measurement is complete. The first CPU determines whether or not the measurement is completed by checking the seam detection signal. (Whether or not the inspection of the set length is completed is performed by the second CPU, which will be described later.) When the seam detection signal is obtained, the conveyance system is stopped and the end signal is transmitted to the second CPU to process necessary data. Then, it prints out to the first output unit. As described above, the first CPU mainly controls the transport system during color measurement. During the inspection, the first display will show the inspection conditions etc.
Is displayed, so that the inspector can always check the contents.

The second CPU side will be described. When the power is turned on, the initial state is set. When the inspection condition is received from the first CPU, the presence or absence of a white calibration signal is checked next.
If yes, perform white calibration. (The actual operation depends on the color sensor used, and the description is omitted.) At this time, this system is equipped with a linear motor that moves the white calibration plate to the position of each color sensor, and calibration is performed in order. Can be done. When finished, it sends an end signal to the first CPU. Next, the presence or absence of reference color calibration is checked. When there is, the reference sample is moved by the linear motor and calibration is performed in order as in the case of white. At this point, the reference color value (L0 * a0 * b0 *) for inspecting the color difference of the measured object is set on the second CPU side. After this, a setting confirmation signal is sent to the first CPU to complete the setting before measurement.
Next, the presence or absence of the measurement start signal is checked. The operation of the second CPU after receiving the measurement start signal is mainly to identify the colorimetric points of the sheet-like object, perform colorimetric measurement on a plurality of color sensors in the same manner, and collect colorimetric data. , In real time as a color difference variation graph on the second display unit. At this time, in the color measurement of the present system, a method is adopted in which a plurality of data obtained at a constant interval are combined into one block of data. For example, data obtained by measuring 5 points at 1 m intervals is averaged, and the averaged colorimetric value is used as a representative point of 4 to 5 m. By doing this, in the case of a long inspection object such as a sheet-like object, data is actually taken in detail and in detail, the necessary and sufficient number of data is displayed, and the data is compressed and recorded. There is also a merit that it can be done. Here, the length of the sheet-like material can be measured by attaching a rotary encoder (not shown) to the conveying system motor and counting the number of well-known pulses. Therefore, when the sheet-like object travels and reaches the set length, the second CPU finishes the measurement and sends a termination signal to the first CPU. And the second
The color difference variation graph displayed on the second display unit is immediately output to the output unit (printer). However, even when the first CPU detects the seam and sends an end signal to the second CPU, the second CPU accepts the end signal and prints out the result up to that time and the color difference variation graph. In this manner, the inspection efficiency is remarkably improved because priority is given to whichever condition is first met.

FIG. 6 is an example of a color difference variation graph output by the woolen fabric color difference inspection device having such a configuration. A woolen fabric with a length of 55 m and a width of 1.6 m is applied at a cloth speed of 35 m /
It is an inspection result when the vehicle is run in minutes. The horizontal axis represents the length (unit: m) and the vertical axis represents the color difference value ΔE, and the data measured by the three color sensors are recorded at regular intervals. The graph below is also plotted with the vertical axis representing the color difference on the lightness axis (L * axis). The above numerical values and the like are examples of conditions, color difference determination results, and the like that are output as necessary.

[0012]

As described above, according to the present invention, when the color difference inspection of the sheet-like object is performed, the control of the conveying system, the input system, the joint detection and the like by the plurality of CPUs and the sheet form of the plurality of color sensors are performed. The color difference (color unevenness, stain etc.) inspection result can be obtained in real time and the inspection length can be set by each CPU controlling the simultaneous color measurement, data collection and color difference variation graph display while the object is running. If not set, the joint is detected, the inspection length is checked, and the one that meets the condition first is given priority.If the inspection end signal is accepted, the result up to that time and the color difference variation graph are printed out. It has become possible to use it as an extremely efficient sheet-shaped material color difference inspection device.

[Brief description of drawings]

FIG. 1 is a General Fl showing a general inspection procedure in an online color difference inspection when a color sensor is used.
It is ow Chart.

FIG. 2 shows a basic system configuration block diagram of a sheet-shaped material color difference inspection apparatus according to the present invention.

FIG. 3 shows a conceptual diagram of a system configuration.

FIG. 4 shows an operation flowchart of a sheet-shaped material color difference inspection device including two CPUs as an embodiment of the present invention.

FIG. 5 shows an operation flowchart of a sheet-shaped material color difference inspection device including two CPUs as one embodiment of the present invention (continuation of FIG. 4).

FIG. 6 is an output example of a color difference variation graph.

[Explanation of symbols]

1: 1st CPU, 2: 1st display part, 3: 1st output part,
4: Transport drive motor, 5: Transport system drive control input section (switch), 6: Inspection condition input section (keyboard),
7: 2nd CPU, 8: 2nd display part, 9: 2nd output part, 1
0: color sensor, 11: white calibration plate, 12: reference sample of measurement object, 13: linear motor, 14: guide rail, 15: sheet-like object, 16: seam, 17: seam detection sensor (area sensor), 18: Seam detection device (image processing device)

Claims (1)

[Claims] 1. A transport unit for running a sheet-shaped object in a strip shape, an input unit for inputting inspection conditions, a first display unit for displaying inspection conditions, a first output unit for outputting results, and detection of a joint between sheet-shaped objects. A first CPU for overall control of the unit, a plurality of color sensors located above or below the sheet, and a second CPU connected to the color sensors and connected to the first CPU via a communication line The CUP includes a second display unit that processes the color measurement of the color sensor and the read data to detect and display the color difference of the sheet-like object, and the color difference that is configured by the device of the second output unit that outputs the graph result. In the inspection device, whether the inspection up to the set length of the sheet-like object is completed or the seam of the sheet-like object is detected, whichever comes first, the traveling of the sheet-like object is stopped with priority. And then A sheet-like material color difference inspection method, which prints out the results obtained in 1 and the data of the color difference variation graph as a graph.