JPH0540099A - Fuzz inspecting device - Google Patents

Abstract

PURPOSE:To obtain the title device capable of inspecting the fuzz of a fabric on-line at every kind regardless of the running speed of the fabric even in a process wherein different kinds flow continuously. CONSTITUTION:After the level of the electric signal from a CCD camera is changed by a gain variable amplifier 7 corresponding to the running speed of a fabric 4, fuzz detection output is taken out by a discriminator 9. Therefore, even when the speed of the fabric 4 is changed, the fuzz can be accurately inspected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluff inspection device for inspecting fluff of a running woven cloth online.

[0002]

2. Description of the Related Art In the manufacturing process of woven fabrics made of glass fibers, carbon fibers, synthetic fibers, etc., fluff is likely to be formed on the surface of the woven fabrics because the yarns are rubbed by the parts in contact with each other and the single yarns are broken.

Further, in the manufacturing process of the raw yarn, fluff has already been generated at the time of spinning or twisting, which is also a cause of the fluff of the woven fabric.

In particular, since glass fibers are easily broken and easily fluffed, improvement of binders, sizing agents, etc.
Improvements in the conditions of the weaving process have been made.

On the other hand, when the prepreg and the copper foil are laminated in the manufacturing process of the printed wiring board in which the woven glass cloth is used as the insulating reinforcing base material, the projections on the surface of the prepreg formed by the fluff damage the copper foil and the normal This is a cause of trouble such as inability to form a circuit, and further improvement is required as the density of printed wiring boards increases.

However, since the fluff of the glass woven fabric is thin and small, it is difficult to visually inspect the fluff of the running glass woven fabric. It was impossible to inspect over the entire length.

Therefore, even if the binder, the sizing agent and the like were improved, and the conditions of the weaving process were improved, the effect could not be quantitatively confirmed and sufficient examination could not be conducted.

Usually, the fluff generation state of the glass woven fabric is concentrated over the entire width, continuously concentrated on the right side or left side in the width direction of the woven fabric, and in the width direction or the length direction. It is divided into the case where the stripes continuously occur and the case where the stripes occur randomly at all.

In order to perform process quality control and product quality assurance, it is necessary to accurately grasp the fluff generation state.

According to the conventional fluff inspection technique, the diameter is 10 μm.
Below, it was difficult to inspect the generation state of fluff having a length of 10 mm or less.

Recently, in Japanese Patent Laid-Open No. 62-108136, Japanese Patent Laid-Open No. 58-215571 and Japanese Patent Laid-Open No. 58-76571, a method for detecting fluff by a laser and Japanese Patent Publication No. 53-37950 are disclosed. Disclosed is a method and apparatus for detecting fluff in a fabric in combination with the disclosed method for detecting defects in a fabric.

In this method, there is described a method in which a lens provided in front of a laser light source spreads the laser light in parallel and irradiates only the fluff. However, when the laser light is spread, the irradiation intensity of the laser decreases and scattering from the fluff occurs. Since the intensity of light decreases, there is a problem that it becomes difficult to detect.

Further, it is described that irradiation is performed at a position where only the fluff is irradiated within a range where the woven cloth is not directly irradiated, but since the woven cloth usually vibrates even on a roll where the woven cloth is difficult to vibrate, In order not to irradiate the woven cloth, it is necessary to irradiate it away from the woven cloth surface. Therefore, the short fluff is not irradiated with the laser light, and the short fluff cannot be detected. Moreover, the fluff on the surface of the woven cloth is rarely standing perpendicular to the woven cloth, and most of the fluff is tilted. Therefore, fluff tilted along the surface of the woven cloth cannot be detected even if it is long. There's a problem.

Further, according to this method, when the woven glass cloth is running, the amount of light received by the CCD camera is changed by changing the time during which the fluff scatters the laser light depending on the running speed. The level of the electrical signal changes and normal test results cannot be obtained.

Usually, in the weaving process, the weaving speed of the loom is as low as several tens of meters / hr, so that the number of looms is large, and inspecting on the loom requires as many inspection devices as the number of looms. is not. Therefore, in order to perform 100% inspection with a small number of inspection devices, it is desirable to perform an inspection in a heat cleaning step of removing the binder or sizing agent of the woven cloth or a finishing step of surface-treating the woven cloth with a silane coupling agent or the like. ..

Usually, in the heat cleaning step and the finishing step, the woven cloth wound in a roll is continuously processed at a running speed of 30 m / min or more. In addition, the traveling speed of the woven fabric is usually different for each type.

In such a process, if the inspection result changes depending on the running speed of the woven cloth, quantitative inspection such as comparison between rolls cannot be performed.

[0018]

As described above, according to the conventional technique, it is difficult to inspect the number of fluffs, the position thereof, and the fluff generation state of the running woven fabric online.

Therefore, an object of the present invention is to run a woven cloth,
In particular, to provide a fluff inspection device capable of inspecting fluff of a woven fabric traveling at a speed of 30 m / min or more online regardless of the traveling speed of the woven fabric, and even in a process in which different varieties continuously flow. is there.

[0020]

In order to solve the above problems, the present invention provides a projector for irradiating a surface of a running woven fabric with a light beam substantially parallel to the width direction of the woven fabric, and the light beam. A CCD camera that receives scattered light obtained by being scattered by the fluff on the surface of the woven fabric and converts it into an electrical signal, and amplifies the electrical signal from the CCD camera with a gain that changes according to the running speed of the woven fabric. Variable gain amplifier,
And a separator for extracting a fluff detection output by separating a signal having a predetermined level or higher among the electric signals amplified by the variable gain amplifier.

[0021]

According to the present invention, the level of the electric signal from the CCD camera is changed by the variable gain amplifier according to the running speed of the woven cloth, so that even if the running speed of the woven cloth changes, the fluff inspection is performed accordingly. Since the result does not change, normal inspection can be performed. Therefore, even in the process in which the traveling speed changes for each product type, it is possible to inspect the number of fluffs of the woven fabric and their positions and the fluff generation state online.

[0022]

Embodiments of the present invention will now be described in detail with reference to the drawings.

2 and 3 are views showing an example of the arrangement of the projector and the CCD camera in the embodiment of FIG.

FIG. 1 is a block diagram showing an embodiment of the fluff inspection apparatus of the present invention.

Here, 1 is a projector, 2 is an output beam from the projector 1, 3 is a CCD camera as a light receiver, 4 is a glass woven cloth, 5 is fluff, 6 is a roll for guiding the glass woven cloth, 7 Is a variable gain amplifier for receiving the fluff detection output from the CCD camera 3, and 8 is A for A / D converting the output of the amplifier 7.
A / D converter, 9 is a sorter for taking out a signal having a level equal to or higher than a certain threshold value from the digital output from the A / D converter 8 as a fluff detection output, and 10 is 1 with respect to the output of the sorter 9.
Primary calculator for performing the next calculation, 11 is a secondary calculator for performing a secondary calculation on the output of the primary calculator 10, 12 is a display for displaying the output of the secondary calculator 11, and 13 is a secondary A printer for printing the output of the arithmetic unit 11, a pulse 14 for generating a pulse in response to the rotation of the roll 6, and a pulse for outputting the seam of the glass woven fabric 4, that is, the length from the initial position in the form of the number of pulses. A length measuring device using an oscillating rotary encoder, 15 is a speed converter that measures the speed of the glass woven fabric 4 according to the time interval of the output pulse from the length measuring device 14, and 16 is a seam detector. Detect the seam indicating the first position of 4.
The encoder as the length measuring device 14 rotates in cooperation with the roll 6 and is activated by the start output from the seam detector 16 to generate a pulse in response to the rotation of the roll 6, thereby making the seam of the woven glass cloth 4, that is, the pulse. The length from the first position is output in the form of the number of pulses. The gain of the variable gain amplifier 7 is changed by the signal from the speed converter 15 indicating the traveling speed of the woven fabric 4.

In the process in which different types of woven fabrics are connected and run continuously at a high speed, it is necessary to start and stop the inspection every 2000 m length, for example, every time the types of products wound in a roll shape are replaced. .. It is possible to detect such a seam of different kinds by the seam detector 16, automatically stop and start the inspection, and change the kind name registered in advance.

As the joint detector 16, a photoelectric sensor composed of a light projector and a light receiver can be used, and either a transmission type or a reflection type may be used.

It is preferable to use a laser light source as the projector 1 because laser light has high directivity and strong scattered light is easily obtained. As such a laser, a semiconductor laser,
A He-Ne laser or the like is used. The light diameter of these laser beams 2 is preferably 10 times or more larger than the diameter of the fluff, because the fluff does not easily block the laser light. The higher the output of the laser, the stronger the scattered light scattered by the fluff, and the more the amount of light received by the CCD camera, the easier the detection and the more preferable. In order to detect thin fluff having a running diameter of 10 μm or less, 5 mw or more is preferable.

As shown in FIGS. 2 and 3, the projector 1
From the viewpoint of detection accuracy, it is preferable that the irradiation position of the laser beam 2, that is, the inspection position is located above the uppermost part of the roll 6 where the woven fabric 4 is less likely to vibrate. That is, when the woven cloth 4 vibrates larger than the light diameter of the laser beam 2, the fluff 5 is not irradiated with the laser light 2 and cannot be detected, which is not preferable.

However, in a normal process, the roll 6 itself vibrates by about 0.1 mm to 0.2 mm, and the roll 6
It is difficult to realize an ideal process in which the vibration does not occur. Therefore, it is preferable to irradiate the woven fabric 4 with the laser light 2 so that short fluff and fluff inclined along the surface of the woven fabric can be detected even if the roll 6 vibrates. That is, according to this, even if the roll 6 vibrates within the range of the light diameter of the laser beam 2, the fluffs 5 can be irradiated, so that the detection can be performed regardless of the influence of the vibration.

Therefore, the laser light 2 is not strictly parallel to the width direction of the woven cloth 4, but is irradiated substantially parallel within the range of the spread angle of the laser light 2 from the laser light source 1 to be used.

Further, the scattering of the laser light 2 differs depending on the inclination of the fluff 5 on the surface of the woven cloth 4. Therefore, as shown in FIG. 3, rather than irradiating from one side of the woven cloth, providing the laser light sources 1 on both sides of the woven cloth 4 and irradiating from both sides is affected by the fluff shape (fluff inclination). It is difficult, so it is preferable.

The position of the CCD camera 3 is, as shown in FIG. 2, from θ = −5 ° to 195 ° with respect to the tangent line drawn at the position of the measuring portion above the roll 6 at a position parallel to the laser beam 2. Positions are preferred, and positions of θ = −5 ° to 70 ° and θ = 140 ° to 195 ° are even more preferred.
That is, if it deviates from the range of θ = −5 ° to 195 °, it becomes difficult for the laser light scattered by the fluff 5 to enter the CCD camera 3. Further, at the position in the range of θ = 70 ° to 140 °, scattered light from the surface of the woven fabric 4 easily enters the CCD camera 3 in addition to scattering by the fluff 5.

As the CCD camera 3, a line sensor camera or an area sensor camera can be used, but the line sensor camera is preferable for inspecting a woven cloth which continuously runs.

That is, the area sensor camera is suitable for inspecting the fluff shape (length, thickness, inclination, etc.) by image processing, but the number of fluff is enormous in the continuous running woven cloth. Yes, it takes too much time to process the image and it is not realistic to inspect online.

Compared to the area sensor camera, the line sensor camera can set a wide field of view per camera with the same resolution per pixel, and can inspect with a small number of cameras.

The number of pixels of the CCD camera 3 sensor and the number of CCD cameras 3 are usually determined by the size of the fluff to be inspected and the required resolution per pixel.

However, there are various forms of fluff on the surface of the woven cloth, and the scattering of the laser differs depending on the form. For example, it is difficult to measure the length of the fluff accurately because there is almost no fluff standing perpendicular to the surface of the woven fabric and it is usually inclined, and the way the laser light is scattered changes depending on the inclination. ..

Further, if the length of the fluff is more than the resolution per pixel of the camera, the same fluff is detected by a plurality of pixels, and the number of fluff cannot be accurately known.

In the embodiment of the present invention, since the pitch of the warp threads of the woven fabric is 0.4 mm to 1 mm, the resolution per pixel is set to 0. so that continuous fluff can be detected on the warp threads. It was set to be smaller than 4 mm.

For example, when a line sensor camera having 2048 pixels is used, it is possible to inspect the entire width of a woven fabric having a width of 1500 mm with two units.

The number of fluffs can be obtained by calculating the detection result for each pixel, but due to the above problems and the enormous amount of data, the number of fluffs is increased online in the process of running at high speed. Since it is difficult to detect, the following two-step processing method was adopted so that the fluff generation pattern could be clearly captured.

First, the fluff detection output from the classifier 9, the length measurement pulse from the length measuring device 14, and the seam detection output from the seam detecting device 16 are supplied to the primary arithmetic unit 10 to start the seam output rising. As the width of the woven fabric 4 is divided into m units, the presence or absence of fluff is determined for each preset unit in the width direction, the determination process is repeated over the units in the length direction, and the entire width is determined for each unit in the length direction. Calculate the number of fluffs in and the position in the width direction.

Next, the output from the primary computing unit 10 is supplied to the secondary computing unit 11, where the width of the woven fabric 4 is divided into n (n>
m) The aggregated value of fluffs for each set interval in the length direction obtained for each inspection width is added, and the number of fluffs continuous in the length direction and the width direction is calculated.

In this way, in this embodiment, not only the comparison of the fluff level based on the number of fluffs, but also the fluff generation pattern such as the fluff concentration occurrence portion and the fluff generation continuously generated in the length direction and the width direction. The position can be captured.

Before the calculation, the magnitude of the electric signal from the CCD camera 3 is changed by the variable gain amplifier 7 according to the running speed of the cloth measured by the speed converter 15, and then the A / D converter 8 is used. Is converted into a digital signal by means of a separator, a signal having a level equal to or higher than a predetermined threshold value is separated by a separator 9 and taken out, and the arithmetic units 10 and 1 are operated based on the separated signal.
The calculation described above in 1 is performed.

Although the embodiment of FIG. 1 uses a discrete circuit, instead of this, the part 9,
10 and 11 are composed of a microprocessor, and the CPU
It is needless to say that the arithmetic processing described above may be performed by controlling the above with a predetermined program.

In FIG. 4, the running speed of the woven fabric is 30 m / min.
An example of the above inspection result is shown. In FIG. 4, the vertical axis is m
The average number of detected fluff per unit, the horizontal axis is the running speed of the glass woven fabric. Here, the broken line shows the inspection result in the device of the present invention including the variable gain amplifier, and the solid line shows the inspection result in the conventional example in which the variable gain amplifier is not used.

As can be seen from FIG. 4, the apparatus according to the embodiment of the present invention can carry out the inspection without the fluff detection number changing depending on the running speed of the woven cloth.

Furthermore, the fluff distribution state can be displayed online while being inspected by the display device 12, and the totalized value for each preset interval for each inspection width obtained by dividing the inspection result by the printer 13 online. It is possible to print with, and it is also possible to print the aggregate value for each roll.

60 m / m with the fluff inspection apparatus of the embodiment of the present invention
FIG. 5 shows an example of the result of the online inspection of the woven fabric running in.

In FIG. 5, the vertical axis represents the running speed of the woven fabric, which is 6
The average number of fluffs detected per m at 0 m / min, the horizontal axis is the type of glass woven fabric. The average number of detections in each of the left, middle and right zones and the average number of detections in the entire width when the inspection width of this glass woven fabric is divided into three are shown for each product type. here,
A is a defective product having fluffs on the entire surface, B is a defective product having fluffs on one side, C is a normal product, and D is a defective product having continuous fluffs. According to FIG. 5, the difference between the varieties and the fuzz generation state are clearly shown.

[0053]

According to the present invention, the level of the electric signal from the CCD camera is changed by the variable gain amplifier according to the traveling speed of the woven cloth, so that the traveling speed of the woven cloth changes accordingly. Since the fluff test result does not change,
You can inspect normally, and as a result, you can inspect the number of fluffs on the running fabric and its position and the fluff occurrence state online,
The effect that can be utilized for process quality control and product quality assurance can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a fluff inspection device for a woven fabric according to the present invention.

FIG. 2 is a diagram showing an example of an arrangement of a light projector and a light receiver in the embodiment of the present invention.

FIG. 3 is a diagram showing an example of arrangement of a light projector and a light receiver in the embodiment of the present invention.

FIG. 4 is a diagram showing an example of a correction effect on the traveling speed of the woven fabric according to the present invention.

FIG. 5 is a diagram collectively showing fluff inspection results of four types.

[Explanation of symbols]

 1 Light Projector 2 Laser Beam 3 CCD Camera 4 Glass Woven 5 Fluff 6 Roll 7 Gain Variable Amplifier 8 A / D Converter 9 Separator 10 Primary Calculator 11 Secondary Calculator 12 Display 13 Printer 14 Length Measurer 15 Speed converter 16 seam detector

Claims (1)

[Claims] 1. A light projector that irradiates a light beam on the surface of a running woven fabric substantially parallel to the width direction of the woven fabric; and a scattered light obtained by scattering the light beam by fluff on the surface of the woven fabric. CCD that receives light and converts it into electrical signals
A camera, a variable gain amplifier that amplifies an electric signal from the CCD camera with a gain that changes according to the running speed of the woven cloth, and a fluff by separating signals of a predetermined level or more among the electric signals amplified by the variable gain amplifier. A fluff inspection device, comprising: a separator for extracting a detection output.