JPS6385142A - Detection of weaving flaw - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for detecting weaving defects, in particular warp defects, on a loom during weaving.

Prior Art When flaws occur in the warp direction during weaving, the entire woven fabric is likely to be defective. Such weaving defects, particularly warp defects, are caused by warp yarn breakage, incorrect threading of the reed or belt, and the like.

For example, in the invention disclosed in Japanese Utility Model Publication No. 1396/1973, in a warp knitting machine, a photosensitive head is reciprocated across the weaving width of the fabric, thereby continuously detecting flaws in the fabric. Also, JP-A-60-23185
In the invention of No. 0, a woven fabric is continuously scanned in the width direction of the woven fabric by an electro-optical scanning head on a loom to detect weaving flaws such as warp lines.

In the above-mentioned conventional technology, flaws in the fabric are converted into electrical signals during the scanning process in the weaving width direction. Or, it is difficult to determine whether it is caused by garbage or fluff. As a result, even when no weaving flaws have occurred, Hl['J is forced to stop, which not only lowers the operating rate, but also causes a stoppage to occur in the fabric. Quality will deteriorate.

On the other hand, in the latter conventional technology, even when a weaving flaw is discovered during the scanning process, scanning is repeated several times over the entire weaving width, and by the time it is finally determined that the weaving flaw is weaving, the weaving still remains. It will continue. This results in the flawed woven fabric being woven for a relatively long period of time, and much time and effort is required to repair the flawed fabric.

OBJECTS OF THE INVENTION Therefore, an object of the present invention is to accurately distinguish between defects such as weaving flaws, especially warp lines, and signals due to dust or fluff during the weaving process, and to detect such defects at an early stage. It is to be.

Solution to the Invention Therefore, the present invention aims to detect abnormal waveforms such as weaving flaws in the process of scanning the cloth over the entire width of the cloth on the loom during weaving and photoelectrically outputting the surface condition of the cloth. At the time of discovery, only the location where the abnormal waveform occurs on the fabric is scanned intensively, and when the abnormal waveform is continuously confirmed in the warp direction, an alarm or an abnormality signal to stop the loom is output.

As described above, in the method of the present invention, scanning is continuously performed over the entire width of the cloth unless an abnormality such as weaving flaws is discovered, but during this process, abnormal waveforms due to weaving flaws or dust are discovered in the detection signal. Then, since the cloth in the area where the abnormal waveform occurs is intensively scanned, appropriate measures can be taken at an early opportunity. In addition, since the continuation of the abnormal waveform is a condition for generating a stop signal, it is possible to distinguish between weaving flaws and dirt and fluff with high reliability.

Structure and operation of the invention First, FIG. 1 shows each process of the invention in the form of a flowchart.

In the first scanning process, the surface of the fabric is scanned in the weft direction over the entire width of the fabric during weaving, and the condition of the fabric surface is photoelectrically detected and converted into an electrical sensing signal. At this time, when this detection signal corresponds to weaving flaws, fluff, etc., it changes in a complicated manner compared to when the weave is in a normal weaving state, and includes an abnormal waveform.

Then, in the next determination process, it is determined whether this detection signal has an abnormal waveform. Such a determination is made, for example, by setting a threshold value on the detection signal and determining the magnitude relationship in the amplitude direction with respect to the threshold value. In this way, unless an abnormal waveform due to weaving flaws or fluff is found during this judgment process, the previous scanning process continues to be performed.

However, if an abnormal waveform is found in this judgment process, in the subsequent detection process, intensive detection is performed only on the location where the abnormal waveform occurs on the cloth. For this intensive detection,
The full-width scan is interrupted and repeated short stroke scans are performed at the location of the abnormal waveform, or by stopping the photoelectric detection head at that location. In this detection process, it is confirmed whether abnormal waveforms are continuously occurring in the warp direction.

Such 6"ffl Lffl is determined by the number of pulses when the detection head is reciprocated in a short stroke, and from the duration of the abnormal waveform when the detection head is stopped. When it is determined that there is a weaving flaw, a stop signal is generated in the next output process.

This stop signal is used as a warning signal for the occurrence of weaving flaws or as a signal for stopping the loom. After this, the loom normally stops, so repair work for the warp threads, etc. is carried out in this state, and the m loom is set to restart again. Even after this restart, the method of the present invention is continuously executed on the FTU.

Example 1 FIG. 2 shows a specific example of implementing the method of the present invention.

The cloth 1 to be detected is placed on a loom and moves in a direction perpendicular to the plane of the paper as weaving progresses. In this process, the detection head 2 reciprocates in the weft direction over the entire width of the cloth 1, illuminates the surface of the cloth 1, and converts the reflected light into an electrical signal, thereby determining the surface condition of the cloth 1. is converted into an electrical detection signal.

Note that the scanning for the reciprocating motion in this case is provided by the endless belt 5 wrapped around the motor 3 and the pair of boots U4. That is, the motor 3 is connected to the power supply 6 through a forward contact r1 of a forward relay F and a reverse contact r1 of a reverse relay R, which are connected in parallel to the power source 6. When the forward contact r1 is turned on to the drive side pulley 4, Rotation in the normal rotation direction is applied, and motion in the reverse direction is applied when the reverse rotation contact r1 is turned on. As a result, the belt 5, via the connector 7, gives a reciprocating motion to the detection pad 2 over the entire width of the cloth 1 as a scanning process.

During this time, the cloth 1 is wound up little by little as weaving progresses, so the detection head 2 detects
The surface of the cloth 1 is sequentially scanned at a predetermined pitch. When the detection head 2 reaches the end of the cloth 1, the dog 8 of the belt 5 is activated by the limit switch S1 or the limit switch S.
2, the forward rotation relay F and the reverse rotation relay R are
Can be switched alternately.

Next, FIG. 3 shows the control circuit 10. This control circuit 10 is constituted by a contact group of relays R1, R2, R3, and R4, which will be described later, in addition to a forward rotation relay F and a reverse rotation relay R between the power supply terminals 9.

First, when pushbutton switch PB is turned on, forward relay F is energized, self-held at contact f2, and contact f
1 causes the motor 3 to rotate in the normal rotation direction. When the detection head 2 reaches, for example, the right end of the cloth 1, the dog 8 contacts the limit switch S2 for reverse rotation, turning off the contact S2b and turning on the contact S2a, which turns off the forward rotation relay F and reverses the limit switch S2. Since the reversal relay R is turned on and self-held at the contact r2, the detection head 2 moves in the reverse direction.

When the detection head 2 reaches the left end of the cloth 1 due to this reversal, the dog 8 contacts the limit switch S1 for forward rotation, turning on the contact Sla and turning off the contact Slb, and the forward rotation relay F switches on the contact f2. Since the detection head 2 is self-held at , the detection head 2 will then move in the normal rotation direction. In this manner, the detection head 2 reciprocates in the weft direction at a predetermined pitch during the weaving process of the cloth 1, repeating the scanning process.

Next, FIGS. 4 and 5 show the process of processing the detection signal detected by the detection head 2. FIG.

During the scanning process, the detection radar 2 emits light from a light source such as a light emitting diode toward the cloth 1, receives the reflected light with a phototransistor, etc., and generates electricity proportional to the amount of light, as shown in FIG. It generates a detection signal of the amount. This detection signal is amplified by an amplifier 1) and sent to the next stage waveform analyzer 12 as a judgment process. Therefore, the waveform analyzer 12 analyzes the amplitude and frequency of the detection signal, separates the abnormal waveform when weaving defects such as warp lines occur from the normal signal waveform, and shapes the abnormal waveform. , is sent to the next counter 13, timer 14 and delay circuit 15 as a pulse-like abnormal signal.

Therefore, when the pulse-like abnormal signal is input, the delay circuit 15 outputs the abnormal signal to one of the one-shot signals depending on the on/off state of the reverse rotation contact r3 or the forward rotation contact f3 after a predetermined delay time t1. Multi-pipe lake 16.
Send it to 17. The delay time t1 at this time is set so that the detection head 2 outputs the signal at a position which has advanced a predetermined distance from the abnormal part of the cloth 1, for example, about 5 mm. At this time, if the detection rod 2 is moving to the forward rotation side, then
Since the contact f3 of the forward rotation relay F is on, the one-shot multivibrator 16 is activated. So, this one shot multi pie break 1
6 continues to generate an "H" level output for the time required to intensively and repeatedly scan the abnormal portion of the cloth 1. While the one-shot multi-pipe rake 16 is generating an "H" level output, the relay R1 is connected to the contact R.
1a is turned on, contact R1b is turned off, and contacts R3a and R3b of relay R3 are placed in the power supply path. Also, over that period, the multi-pipe rake 18 generates, for example, two 1H" level output signals at equal on/off cycles, which drive the relay R3. Of course, the detection head 2 scans in the reverse direction. When the one-shot multi-pipe rake 17 is connected to the contacts R2a, R2b of the relay R2,
and multi-bye break 1 at a predetermined time width.
9 drives contacts R4a and R4b of relay R4.

When the relay R1 is driven, both the forward rotation relay F and the reverse rotation relay R are set to a state in which power can be supplied by the relay R3. During this time, relay R3 repeats on and off four times by multi-vibrator 18 over the @H'' level output period of one-shot multivibrator 16, so forward relay F and reverse relay R are connected to contacts R3a and R3b. The scanning motor 3 is repeatedly turned on and off four times by alternating on and off, and the scanning motor 3 is periodically rotated between normal and reverse rotation in a short period of time. As shown in FIG. 6, scanning is intensively repeated with short strokes, for example, strokes of about 10 mm, near the part where the abnormal signal is generated.

The abnormality in cloth 1 is due to temporary noise caused by wind cotton, etc. (, cloth 1
When the detection head 2 scans with a short stroke during the detection process, an abnormal signal will appear continuously for each scan.

Therefore, during this period, the counter 13 performs the following as a confirmation process:
The abnormal signal is counted and the timer time t2 set by the timer 14, that is, the one-shot multivibrator 16.
When a certain number, for example "4", is counted within the sum of the output time of 17, the delay time of delay circuit 15, and other necessary times, an alarm signal is generated. When the count value of the abnormal signal does not reach a predetermined number within such a period of time, the counter 13 is reset by the output of the timer 14 and automatically returns to the initial state. Of course, the count value of this counter 13 is preset. At this time, the output of the one-butt multi-byte brake 16 is turned off, and the relays R1 and R3 are also turned off, so the detection head 2 and the scanning motor 3 are in a stopped state.

After that, the reset signal of the timer 14 causes the relay R to
5 is turned on, the forward rotation relay F is turned on by its contact R5a, and the motor 3 returns to the forward rotation direction with a stroke of the full width of the cloth 1.

Here, the left side of FIG. 5 shows the state when an abnormality occurs due to fluff, and the right side shows the state when a flaw occurs in the cloth 1. Since abnormal signals such as fluff do not occur continuously, the counter 13 does not generate an alarm output. However, if a warp line occurs as a weaving flaw in the cloth 1, a pulse-like abnormal signal corresponding to the flaw is input in a short stroke scanning period, so the counter 13 When the count value "4" is counted, an alarm signal is output for stopping the vertical position.

Embodiment 2 In Embodiment 1, when an abnormality signal is generated, the detection head 2 is scanned with a short stroke in the vicinity of the abnormality location on the cloth 1, but in this Embodiment 2, when an abnormality signal is received, the detection head 2 is scanned with a short stroke. in,
This is an example in which the detection radar 2 is stopped at that position and the presence of an abnormal signal is continuously determined.

The circuit configuration in this case can be embodied as shown in FIGS. 7 and 8. When an abnormal signal occurs during the detection signal, relay R6 operates and sets its contact R6a to the off state, so the forward rotation relay F and the reverse rotation relay R are immediately turned off, and at that point, the motor 3 Detection head 2
to stop.

At the same time, from the time when the abnormal signal is generated, the timer 20 starts the ninth
As shown in the figure, after a predetermined timer time t2, an "H" level output is generated and sent to one input terminal of AND gates 21 and 22. After the timer time t2 elapses, when the timer 20 generates an “H” level output, the “H” level output is generated.
If the "H" level abnormal signal has already disappeared, the AND condition of the AND gate 21 will not hold.However, if the "H" level abnormal signal continues to occur even after the timer time t2 has elapsed, Since the AND condition is satisfied, at that point the AND gate 21 goes "H" as shown in FIG.
Generate a level alarm signal.

At the time when this abnormal signal is generated, one of the flip-flops 23 and 24 is set depending on the on/off state of the forward rotation contact f2 or the reverse rotation contact r2, and the rotational state at the time the abnormal signal is generated is stored.

When the AND condition for the AND gate 21 is not satisfied, the AND condition for the other AND gate 22 is satisfied between the timer output and the output of the NOT gate 25. (When the AND condition of either AND gate 26 or 27 is satisfied, relay R7 for re-driving the motor 3 in the forward rotation direction or relay R8 for re-driving the motor 3 in the reverse direction
is driven, and the forward rotation relay F or reverse rotation relay R is set to the on state by contact R7b or contact R8b.

Note that the contacts R7a and R8a of these relays R7 and R8
The flip-flops 23 and 24 are set to the reset state.

Modifications of the Invention In each of the above embodiments, signal processing is expressed as a functional block, and control of the motor 3 is shown by a relay circuit, but a series of waveform processing and motor control are performed using the arithmetic control function of a computer. It can also be used in the field of the program.

In the embodiment described above, in order to reduce the influence of disturbance on the detection section, the detection head 2 may be scanned by directly contacting the cloth 1.

Further, in the above embodiment, the detection head 2 is driven by the belt 5, but other driving methods such as a linear motor or the like may be used.

Furthermore, in the confirmation process, the predetermined time was set using the timer 14 or the timer 20, but it is also possible to set the predetermined time by replacing the timer 14 or 20 with a counter and counting the timing signal of the loom. You can also do it.

Effects of the Invention In the present invention, when an abnormal signal is generated during the scanning process for the entire width of the cloth, the abnormal part of the cloth is intensively detected. Therefore, weaving flaws can be prevented from occurring at an early stage. In addition, in the process of processing an abnormal signal, if the abnormal signal continues for a certain period of time, it is determined that it is a weaving flaw, so malfunctions due to fluff or other noise can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a process diagram of the method of the present invention, Fig. 2 is a schematic plan view of the scanning mechanism when implementing the method of the present invention, Fig. 3 is a motor control circuit, and Fig. 4 is a signal processing block. 5 is a flowchart during operation, FIG. 6 is an explanatory diagram of the scanning process corresponding to textile flaws, FIG. 7 is a block diagram of signal processing in another embodiment, and FIG. 8 is a diagram of the motor. Control circuit diagram, No. 9
The figure is a time chart during operation. l...Cloth, 2...Detection head, 3...Motor, lO...
Control circuit, 12... Waveform analyzer, 13... Counter, 1
4...Timer, 15...Delay circuit, 16.17...One shot multi-pipe break, 1B, 19...Multi-by break, 2o...Timer, 21,22...And gate, 23.24...Flip-flop ,26.27・
・And gate, R...Reverse rotation relay, F...Forward rotation relay.

Claims (3)

[Claims] (1) A scanning process in which the cloth is scanned over its entire width during weaving, photoelectrically detecting the surface condition of the cloth and generating a detection signal, and a judgment process in which abnormal waveforms are discovered from the detection signals in this scanning process. When an abnormal waveform is discovered during this judgment process,
A detection process that interrupts scanning across the entire width and concentrates on detecting only the location where abnormal waveforms occur on the fabric, and a confirmation process that confirms weaving defects when the abnormal waveforms continue beyond the range in the warp direction. and an output step of outputting an alarm signal when a weave flaw is confirmed. (2) In the above detection process, weave flaws are intensively detected by scanning short strokes only at the locations where abnormal waveforms occur on the fabric,
2. The method for detecting weaving flaws according to claim 1, wherein in the subsequent confirmation process, weaving flaws are determined based on the number of occurrences of abnormal waveforms. (3) In the above detection process, only the location where abnormal waveforms occur on the cloth is intensively detected in a stopped state, and in the subsequent confirmation process,
2. The method for detecting weaving flaws according to claim 1, wherein the weaving flaws are determined based on the duration of the abnormal waveform.