JPH11323700A - Woven fabric inspection device in loom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject device intended to prevent occurrence of fabric misinspections. SOLUTION: This woven fabric inspection device has such a scheme that a support bar 10 is provided above an expansion bar 25 and a surface roller 26 in the direction of the weave width of a woven fabric W and also mounted with a rail 11; a sensor head 14 is slidably supported upon the rail 11 and designed to make reciprocating motions on a scanning path along the rail 11; the space above the expansion bar 25, the surface roller 26 and a press roller 27 is covered with a cover 22, and the scanning path for the sensor head 14 is covered with the cover 22 as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weaving device using a photoelectric sensor which includes a light receiving portion for picking up light reflecting the weaving state of a woven fabric on a loom, and outputs an electric signal corresponding to the amount of light received by the light receiving portion. The present invention relates to a woven cloth inspection device for detecting a defect of a cloth.

[0002]

2. Description of the Related Art A woven cloth inspection apparatus of this type is disclosed in Japanese Patent Laid-Open Publication No.
No. 1648, and Japanese Patent Application Laid-Open No. 9-78444. The inspection device disclosed in Japanese Patent Application Laid-Open No. 9-78444 is disposed so as to face a woven cloth path between a woven cloth feeding section and a take-up roller. The inspection apparatus includes a storage box-type reflector that reflects irradiation light from an internal light source toward a woven fabric surface. In the conventional apparatus disclosed in Japanese Patent Application Laid-Open No. 4-361648, a reciprocating sensor head is housed in a housing box, and the housing box faces a woven cloth path below the woven cloth between the cloth fell and the expansion bar. It is arranged. The storage box type woven cloth inspection device is effective in preventing an inspection error caused by disturbance light.

[0003]

The relative positional relationship between the woven fabric surface and the woven fabric inspection device must be unchanged in order to avoid an inspection error. However, in the conventional apparatus disclosed in Japanese Patent Application Laid-Open No. 9-78444, since the winding diameter of the woven fabric at the winding roller changes, the relative positional relationship between the woven fabric surface and the inspection device fluctuates. Easy to occur.

[0004] At both ends of the woven fabric between the cloth fell and the expansion bar, the warp is inclined with respect to the traveling direction of the woven fabric, and the characteristics of the yarn arrangement are different between the center side and the end side of the woven fabric. The closer the warp is to the cloth fell, the greater the inclination of the warp is. In the conventional apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 4-361648, in which a storage box is disposed below the woven fabric between the cloth fell and the expansion bar, the installation position of the storage box is regulated by the expansion bar, and the scanning path of the sensor head is controlled. Must be closer to the weave side. For this reason, there is a possibility that a detection error may occur due to a difference in the characteristics of the yarn arrangement.

[0005] In addition, a woven cloth inspection device having a storage box type configuration results in an increase in cost. SUMMARY OF THE INVENTION An object of the present invention is to provide a woven cloth inspection device that suppresses the occurrence of an inspection error.

[0006]

To this end, the present invention provides a light projecting unit for projecting light onto a woven fabric on a loom, and picking up light projected by the light projecting unit and reflecting the weaving state of the woven fabric. The present invention is directed to a woven fabric inspection device that includes a light receiving unit and detects a defect of the woven fabric using a photoelectric sensor that outputs an electric signal according to the amount of light received by the light receiving unit. The upper part of the surface roller and the press roller for taking up the woven fabric is covered with a cover, and at least the light receiving unit is provided between the cover and the movement path of the woven fabric.

According to a second aspect of the present invention, in the first aspect,
The light receiving unit was mounted on a sensor head that moved in the weaving width direction of the woven fabric. In claim 1 and claim 2, the surface roller and the press roller are pulled with a woven cloth interposed therebetween,
The cover prevents foreign matter (for example, an operator's hand) from contacting the rotating surface roller and press roller. Such a cover for preventing foreign matter contact prevents the disturbance light from entering the light receiving portion. The light receiving section can be separated from the cloth fell as close as possible to the surface roller and the press roller side, and it is possible to reduce a detection error due to a difference in yarn arrangement characteristics between the center side and the end side of the woven fabric.

According to a third aspect of the present invention, in any one of the first and second aspects, the woven fabric is brought into contact with an expansion bar for preventing the shrinkage of the woven fabric on the upstream side of the surface roller, and is guided. The cover is covered with the cover up to the woven fabric path upstream of the expansion bar, and light reflecting the weaving state on the woven fabric path upstream of the expansion bar is picked up by the light receiving section.

[0009] The inspection on the woven fabric path close to the expansion bar contributes to the reduction of the inspection error due to the difference in the yarn arrangement characteristics between the center side and the end side of the woven fabric. According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, the first proximity portion which is closer to the woven fabric path upstream of the expansion bar, and which is closer to the peripheral surface of the press roller. The cover having a second proximity portion,
The light receiving section is disposed between the first proximity section and the second proximity section.

[0010] The presence of the first and second proximity portions in the cover contributes to suppressing the intrusion of the disturbance light from reaching the light receiving portion.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIGS. 1A and 1B, the woven fabric W is guided to a cross roller (not shown) through an expansion bar 25, a surface roller 26 and a press roller 27. You. Expansion bar 2
Numeral 5 prevents the shrinkage of the woven fabric W in the weave width direction, that is, the weft in the yarn direction. Surface roller 26 and press roller 2
7 sandwiches the woven fabric W and takes it.

As shown in FIG. 1A, a support bar 10 is disposed above the expansion bar 25 and the surface roller 26. As shown in FIG. 2, the support bar 10 is disposed in the woven width direction of the woven fabric W. Support bar 1
0 is a rail 11, an inspection motor 13 and a guide pulley 1.
6 is attached. A drive pulley 15 is fixed to the output shaft of the detection motor 13, and an endless belt 12 is wound around the drive pulley 15 and the guide pulley 16. The endless belt 12 reciprocates by the reciprocating drive of the detection motor 13. Rail 11 has sensor head 1
4 is slidably supported and has an endless belt 12.
Has a sensor head 14 fixed thereto. The sensor head 14 rotates the rail 11 by reciprocating the endless belt 12.
Reciprocate in a scanning path along.

The sensor head 14 includes a light projector 17 serving as a light projecting unit, an imaging lens 18, a pair of light receiving elements 19 and 20 serving as photoelectric sensors, and a signal processing circuit board 21.
The light projected from the light projector 17 is directed onto the woven fabric W on the upstream side of the expansion bar 25. Imaging lens 1
8 forms an image of the upper surface of the woven fabric W on a plane coinciding with the light receiving surfaces of the pair of light receiving elements 19 and 20. Light receiving elements 19, 20
Is a shape in which the width of the warp T in the yarn arrangement direction is narrow and is long in the warp T in the yarn direction.

A detection range 191 shown in FIG. 4 represents a range on the woven fabric W formed on the light receiving element 19 by the imaging lens 18, and a detection range 201 is formed on the light receiving element 20 by the imaging lens 18. Represents the range on the woven fabric W. The widths of the detection ranges 191 and 201 of the warp T in the yarn arrangement direction are the same h, and the width h is smaller than half P / 2 of the yarn arrangement pitch P of the warp T. Further, the warp T of the detection range 191,201
Have the same length in the yarn direction, and this length is set to a length including, for example, about 10 weft yarns Y. The two detection ranges 191 and 201 are shifted by half the yarn arrangement pitch P in the yarn arrangement direction of the warp T.

The light receiving elements 19 and 20 convert the received light into a current. This converted current signal becomes an electric signal corresponding to the amount of received light. 4 shows a circuit configuration on the signal processing circuit board 21. The light receiving element 19 outputs the converted current signal to the current-voltage conversion circuit 28, and the light receiving element 20 outputs the converted current signal to the current-voltage conversion circuit 29. The current-voltage conversion circuits 28 and 29 convert the converted current signals into voltage signals S1 and S2 and output them to the difference calculation circuit 30. A waveform S1 in FIG. 5 represents a voltage signal output from the current-voltage conversion circuit 28,
The waveform S2 represents a voltage signal output from the current-voltage conversion circuit 29. Note that the fluctuations in the values of the voltage signals S1 and S2 are as follows.
For example, the output voltage is as small as 5 millivolts for 1 volt.

The difference calculation circuit 30 is a dual current-voltage conversion circuit 2
The difference between the values of the voltage signals S1 and S2 input from 8 and 29 is calculated. The waveform ΔS in FIG. 5 represents a difference signal output from the difference calculation circuit 30. The difference calculation circuit 30 outputs the difference signal ΔS obtained by the calculation to the comparison circuit 32 via the band-pass filter 31. The bandpass filter 31 outputs the difference signal ΔS
The waveform signal other than the signal of the frequency around the frequency is cut.

The comparison circuit 32 receives the input difference signal ΔS and a reference value V (>
0). When the value of the difference signal ΔS exceeds the reference value V, the comparison circuit 32 outputs a signal indicated by a waveform H in FIG. The control signal generation circuit 34 outputs a control signal K indicated by a pulse-like waveform in FIG. The counter 35 measures a time interval tx between the control signals K based on the number of pulse signals output from the reference clock 36. This measurement information is sent to the comparison circuit 37.

The comparison circuit 37 has a reference interval [to-Δt, to + Δ] preset by the reference value setting circuit 38.
t] is compared with the measured time interval tx. tx
Is outside the range of [to−Δt, to + Δt], the comparison circuit 37 outputs an abnormality detection signal to the output circuit 39. If tx is within the range of [to−Δt, to + Δt], the comparison circuit 37 does not output the abnormality detection signal to the output circuit 39. The output circuit 39 outputs a defect detection signal to a loom control computer (not shown) according to the input of the abnormality detection signal output from the comparison circuit 37. The loom control computer for controlling the operation of the loom drive motor (not shown) instructs the stop of the operation of the loom drive motor in response to the input of the defect detection signal, and the weaving is stopped by this command.

Assuming that the moving speed of the sensor head 14 is v and the magnification of the imaging lens 18 is m, the image combined on the light receiving plane of the light receiving elements 19 and 20 by the imaging lens 18 moves at the speed mv. The detection ranges 191 and 201 having a width h smaller than the yarn arrangement pitch P of the warp T are shifted in the arrangement direction of the warp T by half P / 2 of the yarn arrangement pitch P. Therefore,
If the yarn arrangement pitch of the warp T is always equal to the predetermined yarn arrangement pitch P, the time interval tx of the control signal K is substantially equal to P / mv. P / mv is adopted as the reference value to, and Δt is an allowable tolerance.

A comparison circuit 32, a reference value setting circuit 33, a control signal generation circuit 34, a counter 35, a reference clock 36,
A defect presence / absence determining means composed of the reference value setting circuit 38 and the comparison circuit 37 determines the presence or absence of a defect based on the difference ΔS calculated by the difference calculation circuit 30. This difference ΔS
The calculation of (1) suppresses a change in an electric signal due to the influence of disturbance such as illumination light and fly wool.

Although the warp T is passed between adjacent reeds in a fixed number of units, for example, the number of warps passed between certain reeds is not sufficient, and the number of warps passed between adjacent reeds is specified. There may be situations where there are more. If such a situation continues, a so-called warp line is formed on the woven fabric, resulting in a defective woven fabric. In FIG. 5, a region Wt1 in the weaving width direction of the woven fabric W is shown.
Represents a rough portion due to the occurrence of a warp, and a region Wt2 represents a dense portion due to the occurrence of a warp. The width h in the yarn arrangement direction of the warp T in the detection ranges 191 and 201 of the light receiving elements 19 and 20 is the warp T
Is set to be equal to or less than the yarn arrangement pitch P, and both detection ranges 19
1,201 is a half P / 2 of the yarn arrangement pitch P in the yarn arrangement direction.
It has been shifted only. Detection range 1 of each light receiving element 19, 20
Since the width of each of the detection ranges 191 and 201 is on the arrangement position of the warp T, the value of the electric signal obtained when one of the detection ranges 191 and 201 is on the warp T
Is the largest when it is between the array positions. Therefore, half P of the yarn arrangement pitch P
By shifting both the detection ranges 191 and 201 in the movement direction of the detection ranges 191 and 201 by / 2,
The difference ΔS between the values of S2 is the largest. The greater the difference ΔS, the more accurate the determination of the presence or absence of a defect.

As shown in FIG. 3, mounting brackets 4 are provided on the inner surfaces of the left and right side frames 40 and 41 of the loom.
2, 43 are fastened and fixed. Press roller 27
Are rotatably supported by the mounting brackets 42 and 43. A stay 4 is provided on the mounting brackets 42 and 43.
4 and 45 are fastened and fixed via mounting blocks 46 and 47. Support blocks 48 and 49 are fastened and fixed to opposing surfaces of both stays 44 and 45. Connecting pieces 50, 51 are provided on the support blocks 48, 49, respectively.
2 and 53, the fitting pieces 50, 5
An end of the support bar 10 is fastened and fixed to 1.

As shown in FIGS. 1A, 1B and 2, the expansion bar 25 and the surface roller 26
A cover 22 is provided above the press roller 27. A pair of rubber supports 54 and 55 are fixed to the inner surfaces of the side frames 40 and 41, respectively, in a line in front and rear. The end of the cover 22 is fitted to the supports 54 and 55. The cover 22 includes an upper plate 221 and an upper plate 2
A hanging part 222 hanging from the front edge of the upper part 21;
And a hanging part 223 hanging from the trailing edge. Hanging part 2
The lower edge of 23 is close to the woven fabric path upstream of the expansion bar 25. The upper plate portion 221 has a concave portion 224
Are formed. The lower surface of the recess 224 is close to the peripheral surface of the press roller 27.

The cover 22 includes an expansion bar 25,
The support bar 10 and the sensor head 14 cover the periphery of the surface roller 26 and the press roller 27, and are located between the hanging portion 223 and the recess 224. That is, the scanning path of the sensor head 14 including the light receiving elements 19 and 20 serving as light receiving portions is between the hanging portion 223 and the recessed portion 224.

In the first embodiment, the following effects can be obtained. (1-1) Surface roller 26 that picks up woven fabric W
In addition, a loom provided with the press roller 27 is generally provided with a cover for preventing foreign matter (for example, an operator's hand) from contacting the rotating surface roller 26 and the press roller 27. When the disturbance light hits the woven fabric W and is received by the light receiving elements 19 and 20, the accuracy of detecting the presence or absence of a defect is reduced. The cover 22, which prevents foreign matter from contacting the surface roller 26 and the press roller 27, prevents the light receiving elements 19, 20 as light receiving units from receiving disturbance light.
Therefore, a decrease in detection accuracy due to the reception of disturbance light in the light receiving elements 19 and 20 is avoided. (1-2) The configuration in which the scanning path of the sensor head 14 is covered by the cover 22 that covers the periphery of the surface roller 26 and the press roller 27 contributes to suppressing an increase in cost when employing the woven fabric inspection device. Further, since the fly 22 is prevented from being deposited on the scanning drive system of the sensor head 14 by the cover 22, smooth scanning of the sensor head 14 is maintained. (1-3) The inclination of the warp T at the end We of the woven fabric W with respect to the traveling direction of the woven fabric W becomes smaller as the woven fabric W becomes farther from the weave front W1. The scanning path of the sensor head 14 can be as close as possible to the surface roller 26 and the press roller 27 and as far as possible from the cloth fell W1. Accordingly, it is possible to reduce a detection error caused by a difference in the yarn arrangement characteristic, that is, the inclination of the warp T between the center side and the end We of the woven fabric W.
In the present embodiment, the coincidence between the longitudinal direction of the pair of detection ranges 191 and 201 and the yarn direction of the warp T is important in improving the detection accuracy. Therefore, the configuration in which the scanning path of the sensor head 14 is moved closer to the surface roller 26 and the press roller 27 and is as far as possible from the cloth fell W1 improves the inspection accuracy of the cloth inspection device using the pair of light receiving elements 19 and 20. It is effective in doing. (1-4) The inspection on the woven fabric path upstream of the expansion bar 25 and close to the expansion bar 25 is performed by the difference in the yarn arrangement characteristics between the center side and the end We side of the woven fabric W. It contributes to the reduction of mistakes. (1-5) The hanging portion 223 is a first proximity portion that is closer to the woven fabric path upstream of the expansion bar 25.
The concave portion 224 is a second proximity portion that is close to the peripheral surface of the press roller 27. The existence of the hanging portion 223 and the recessed portion 224 which are the adjacent portions is determined by detecting the light receiving elements 19 and 2 from outside the cover 22.
0 is prevented. In addition, the concave portion 224 contributes to improving the strength of the cover 22. (1-6) The vibration peculiar to the loom is suppressed from spreading to the sensor head 14 due to the presence of the cushion rubbers 52 and 53. Therefore, deterioration of the sensor head 14 due to vibration is suppressed. (1-7) When the warp T of the warp beam is consumed, a new warp beam is mounted on the loom in place of the old warp beam. The warp of the new warp beam is connected to the warp T of the woven fabric W left on the loom. The seam between the warp of the new warp beam and the old warp T is a combination of a plurality of old warps and a plurality of new warps. Such a seam rises from the moving surface of the woven fabric W. The sensor head 14 is as close as possible to the surface of the woven fabric in order to increase the inspection accuracy. Therefore, if the sensor head 14 is at the position shown in FIG. 1A, the seam passing through the scanning path of the sensor head 14 interferes with the sensor head 14, and the sensor head 14 is damaged. When moving the woven fabric W so that the seam passes through the scanning path of the sensor head 14, the cover 22 is removed and the connecting pieces 50, 5 are removed from the support blocks 48, 49.
If 1 is removed, the sensor head 14 is moved away from the woven fabric surface. Therefore, the seam does not interfere with the sensor head 14 and the sensor head 14 is not damaged.

Next, a second embodiment shown in FIGS. 6 and 7 will be described. The same components as those in the first embodiment are denoted by the same reference numerals. In this embodiment, the rail 11, the inspection motor 13 and the guide pulley 16 are attached to the cover 22, and the sensor head 14 is slidably supported on the rail 11.

In the second embodiment, when the woven fabric W is moved so that the seam passes through the scanning path of the sensor head 14, the cover 22 is removed and the sensor head 1 is moved.
4 is moved away from the woven surface. Therefore, the seam does not interfere with the sensor head 14 and the sensor head 14 is not damaged.

In the present invention, the following embodiments are also possible. (1) Connect the sensor head 14 to the expansion bar 25,
(2) Scanning the woven fabric W between the expansion bar 25 and the surface roller 26 with light projected from the light projector 17, disposed at a position surrounded by the surface roller 26 and the press roller 27. Expansion bar 25
Warp T in the woven fabric W between the belt and the surface roller 26
Almost disappears. Therefore, there is no inspection error due to a difference in the yarn arrangement characteristics between the center side and the end We side of the woven fabric W. (2) In the first embodiment, the support bar 10 is attached to the expansion bar 25, and the scanning path of the sensor head 14 is set to correspond to the upstream or downstream woven fabric surface of the expansion bar 25. The expansion bar 25 and the support bar 10 vibrate integrally, and the relative distance between the light projector 17 and the woven fabric surface to be projected does not fluctuate, so that the inspection accuracy is improved. (3) The present invention is applied to a non-scanning type cloth inspection device.

[0030]

As described above in detail, according to the present invention, the inspection roller is provided between the surface roller and the cover covering the press roller, which take up the woven fabric in cooperation with each other, and the moving path of the woven fabric. Since the light receiving section is provided, an excellent effect that the occurrence of a detection error can be suppressed can be achieved.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment, and FIG. (B) is a schematic plan view.

FIG. 2 is a front sectional view incorporating an enlarged sectional view of the sensor head.

FIG. 3 is a partially omitted back sectional view.

FIG. 4 is a combination diagram of a detection range on a woven fabric and a signal processing circuit.

FIG. 5 is a graph illustrating signal processing in a signal processing circuit.

FIG. 6 is a sectional side view of a main part showing a second embodiment.

FIG. 7 is a partially omitted back sectional view.

[Explanation of symbols]

14: Sensor head, 17: Floodlight to be a illuminator, 1
9, 20 ... photoelectric sensor and light receiving element serving as light receiving section, 22
... Cover, 223...
.., A concave portion serving as a second proximity portion, 25, an expansion bar, 26, a surface roller, 27, a press roller,
W: Woven cloth.

Claims (4)

[Claims] A light projecting unit for projecting light onto a woven fabric on a loom; and a light receiving unit for picking up light projected by the light projecting unit and reflecting a weaving state of the woven fabric, and receiving light at the light receiving unit. In a cloth inspection device that detects a defect of a cloth by using a photoelectric sensor that outputs an electric signal according to an amount, a surface roller and a press roller that take up the cloth in cooperation with each other are covered with a cover, A woven cloth inspection device in a loom in which at least the light receiving unit is provided between the cover and the movement path of the woven cloth. 2. A woven cloth inspection device in a loom according to claim 1, wherein said light receiving section is mounted on a sensor head which moves in a woven width direction of said woven cloth. 3. The woven fabric is guided in contact with an expansion bar for preventing weaving shrinkage on the upstream side of the surface roller, and the cover is provided on one side of the woven fabric path upstream of the expansion bar. 3. The weaving device according to claim 1, wherein the light receiving unit covers light, and the light receiving unit picks up light that reflects a weaving state on a woven fabric path upstream of the expansion bar. 4. Cloth inspection device. 4. The cover includes a first proximity portion that is close to a woven fabric path upstream of the expansion bar, and a second proximity portion that is close to a peripheral surface of the press roller, The woven cloth inspection device according to any one of claims 1 to 3, wherein the light receiving unit is located between the first proximity unit and the second proximity unit.