JPH0333262A - Fabric inspection device - Google Patents

Abstract

PURPOSE:To precisely inspect fabric by opposingly arranging a light projecting means and a light receiving means along the whole width of fabric, traveling fabric in a contact with one of both the means, receiving transmitted light and converting it into an electrical signal for fabric inspection information. CONSTITUTION:An emission diode array and a contact type image sensor are opposingly arranged with sandwiching fabric in between the array and the sensor along the whole width of the fabric. The fabric is traveled in a contact state with one of the emission diode array or the contact type image sensor, transmitted light passing through the fabric in an unfluttered state from the emission diode is received by the contact type image sensor and converted into an electrical signal for fabric inspection information.

Description

[Detailed description of the invention] [Industrial application fields] The present invention relates to a fabric inspection device.

[Prior Art] As a fabric inspection method, for example, as disclosed in Japanese Unexamined Patent Publication No. 144147/1980, the transmitted light of the projected light through the fabric is received by an image sensor and fabric inspection information is extracted. , as disclosed in Japanese Patent Application Laid-Open No. 60-231850, a photo sensor receives reflected light from a woven fabric of a spot light projected from a scanning head traveling in the width direction of the woven fabric to obtain fabric inspection information. Take it out or use JP-A-60-18
As disclosed in Japanese Patent No. 5846, there is a method for extracting fabric inspection information by processing images obtained by a photographing device.

[Problem to be solved by the invention] However, in the image processing method using an imaging device, a high-resolution imaging device is required to detect fine detection targets such as weaving flaws on fabric, which is extremely costly. disadvantageous to

In the method of projecting spot light onto a fabric and receiving the reflected light, the flapping of the fabric has a large effect on fluctuations in the receiving area, and detection errors are likely to occur.

Even in a method using an image sensor as a light receiving means, detection errors due to flapping of the fabric cannot be avoided.

An object of the present invention is to provide a fabric inspection device that can avoid such detection errors.

[Means for Solving the Problems] For this purpose, in the present invention, the light projecting means and the light receiving means are disposed opposite to each other across the entire width of the woven fabric across the running path of the woven fabric, and at least one of the light projecting means and the light receiving means is A close-contact type (1-size type) using an image sensor.

[Operation] The running of the woven fabric is guided between the opposing light projecting means and the light receiving means, and the woven fabric runs in contact with the light projecting means or the light receiving means. This contact running suppresses the flapping of the woven fabric, and the adoption of a close-contact image sensor provides high quality fabric inspection information.

[Example] Hereinafter, an example embodying the present invention will be described based on FIGS. 1 to 3.

A cross roll 2 that is wound around a winding shaft 1 at a predetermined speed.
A pair of guide plates 3 and 4 are arranged adjacent to each other across the travel path of the woven fabric W, and one guide plate 3 is made of transparent glass;
The other guide plate 4 is made of frosted glass. Both information boards 3.
4 is set to be slightly larger than the wear of the woven fabric W, and the woven fabric W is guided in contact with the guide plate 3 side.

A plurality of contact type linear image sensors 5 are arranged on the outer surface side of the guide plate 3 made of transparent glass over the weaving width area of the woven fabric W. The linear image sensors 5 are arranged in series so that every other linear image sensor 5 is slightly shifted in the running direction of the woven fabric W, and the ends of adjacent linear image sensors 5 overlap when viewed in the running direction of the woven fabric W. ing. Frosted glass guide board 4
A light emitting diode array 6 is installed on the outer surface side of the linear image sensor 5 so as to face the linear image sensor 5, and the projected light from the light emitting diode array 6 passes through the guide plate 4, the woven fabric W and the guide plate 3 to form a linear image. The light is received by the sensor 5.

4. At the overlapping portion of the linear image sensor 5. A processing method for detecting weave flaws will be explained based on FIG. That is, addresses 1 to n divided in the width direction of the woven fabric W are set inside the weaving flaw detection signal recording section. Further, the time t for the woven fabric W to pass through the linear image sensors 5a and 5b is set in advance. In this case, the amount of fabric moved in time t is set to be slightly larger than the distance of the linear image sensors 5a, 5b in the fabric moving direction.

For example, if a weave flaw W1 exists in the overlapping part of the linear image sensors 5a and 5b, as the woven fabric W moves, the linear image sensor 5b first detects the weave flaw W1, and then the linear image The sensor 5a detects the weave flaw Wl. In this way, if two detection signals are generated within the same time within the same address (for example, 6), processing can be performed by invalidating the latter detection signal and determining that one weave flaw has been detected. . In addition, by adopting a configuration in which the width direction of the woven fabric W is divided into addresses in this way, it is possible to record not only weaving flaw data in the fabric feeding direction as described above but also weaving flaw data in the woven fabric width direction. be able to.

Each linear image sensor 5 is connected to a data processing section 7, and each data processing section 7 processes the detection signal from the linear image sensor 5 and outputs inspection information obtained by this processing to the recorder 8.

A recorder 8 organizes and stores fabric inspection information based on count information from a feed amount counter 9 that detects the rotation type of the cross roll 2. The curve 1'' in FIG. 3(a) is a conversion signal 1IIl line obtained when there is a weaving flaw such as incorrect warp thread threading, and the data processing section 7 uses a preset reference signal value Vo.
The occurrence of weaving flaws is determined by comparing the signal curve T with the signal curve T, and the result of this determination is outputted to the recorder 8. Further, the curve Y in FIG. 3(b) shows the frequency characteristic when there is a defect in the weft direction such as weft loosening, and the data processing unit 7 calculates the reference characteristic value F in the preset low frequency region (fl, f2). , and the average value of the detected characteristic values in the low frequency region (fl, f2) to determine the occurrence of weaving flaws, and output the results to the recorder 8.

+lh line T as shown in FIGS. 3(a) and (b),
In order to obtain such fabric inspection information with high accuracy from a portion of the woven fabric W in the m-weave state represented by Y, it is necessary that the optical platform reaching the linear image sensor 5 from the light emitting diode array 6 and the tissue state of the inspection site are There must be a stable relationship. The flapping of the woven fabric W is a major factor that inhibits this stability, and fabric inspection information in a state where the woven fabric W is flapping lacks reliability. However, in this embodiment, the woven fabric W is guided in contact with the guide plate 3 of the five linear image sensors, so the woven fabric W does not flap. Therefore, the light receiving state of the linear image sensor 5 always stably reflects the tissue state of the inspected portion of the woven fabric W, and accurate fabric inspection information can be obtained for any portion of the woven fabric W.

In addition, the adoption of the close-contact linear image sensor 5 increases the accuracy of information decomposition of the inspected area, and combined with the effect of preventing fabric W from flapping, the accuracy of inspection information is greatly improved compared to conventional methods. Therefore, the cost advantage is obvious.

In addition to the method described above, there is also a method for determining the presence or absence of weaving flaws.
) and (b) are also possible. Figure 4(a)
The curves Y, , Y2. Y3 represents a plurality of consecutive output waveforms, and these four consecutive output waveforms Y, , Y2 . Y
If a portion with a small output value is found by comparing the three, it is determined that there is a weave flaw in the weft direction. Also, the fourth
Curves TI and T2 in figure (b). T3 represents a plurality of output waveforms that are output continuously, and these consecutive output waveforms TIT
2. If a region with a small output value is found in the waveform T4 obtained by superimposing T3, it is determined that there is a weave flaw in the warp direction.

The invention is, of course, not limited to the embodiments described above; for example, the embodiment shown in FIG. 5.6 is also possible.

In this embodiment, each linear image sensor 5 is oriented diagonally, and the light emitting array (not shown) is also arranged accordingly. The song in Figure 6 'ft3S+
, S2, and S3 represent a plurality of output waveforms that are successively output. When the woven fabric W has weaving flaws in the direction of the thread 17, each output waveform Si, s2. s3 has curved part y++ y2
．． As shown by y3, parts with large output values sequentially move toward the origin along the horizontal axis, and if there are weave flaws in the warp direction, each output waveform s, s2 . Sa has a curved part tl.

t2. As shown by t3, portions with smaller output values are generated so as to move away from the origin in sequence along the horizontal axis. Such a fabric inspection method further improves the detection accuracy.

The woven fabric W is guided by contacting at least one of the guide plates 3.4, and this guiding action reduces the flapping of the woven fabric W by 1 fl.
It is being praised. Note that instead of omitting the guide plate 3, a protection film 11 may be provided on the light-receiving surface of the linear image sensor 5 and the woven fabric W may be brought into contact with this protective film, or the guide plate 4 may be omitted and woven directly on the light emitting diode array. It is also possible to steal by bringing the cloth W into contact with each other. It is also possible to employ fluorescent lights instead of the light emitting diode array. Further, the guide plate 4 does not need to be made of glass, and may be made of transparent glass.

Furthermore, the present invention is also applicable to the case of inspecting a woven fabric being woven on a loom.

[Effects of the Invention] As detailed above, in the present invention, since the fabric is inspected by contacting at least one of the contact image sensor and the light projecting means, the flapping of the fabric is eliminated and the inspection accuracy is improved. This has the excellent effect of improving the quality of fabric and making it possible to perform stable fabric inspection without mistakes.

[Brief explanation of drawings]

1 to 3 show an embodiment embodying the present invention.
The figure is a perspective view, Figure 2 is an enlarged side sectional view of the main part, and Figure 3 (a)
, (b) is a graph of the output waveform, Fig. 4 (a),
(b) is a graph showing another sorting method with and without weaving scratches, the fifth
, 6 show separate parts, FIG. 5 is a perspective view, FIG. 6 is a graph of the output waveform, and FIG. 7 is a graph for explaining the 1δ processing of the image sensor overlapping part.

Claims (1)

[Claims] 1. A light emitting means and a light receiving means are installed facing each other across the entire width of the woven fabric across the running path of the woven fabric, and the woven fabric is brought into contact with at least one of the light emitting means and the light receiving means to control the running of the woven fabric. A fabric inspection device that uses a contact image sensor as a light receiving means that receives projected light from a light projecting means that guides and passes through a woven fabric and converts it into an electric signal for pressure detection information.