JP2021148451A - Method for visually inspecting wound yarn package and method for manufacturing multifilament - Google Patents

Abstract

To provide a method for visually inspecting wound yarn package capable of precisely detecting small or linear dirt stretching along in the direction of the roll and defects such as fluff or loops that sticks to the surface of the roll or are buried in the surface layer, and a manufacturing method of multifilament.SOLUTION: Appearance inspection method of a wound thread package in which a thread is wound around a winding thread tube includes the steps of: irradiating the surface of the winding yarn package that rotates in the winding direction of the yarn with light from the lighting device; receiving the reflected light reflected from the surface of the winding yarn package by the light-receiving surface of a line sensor; and detecting anomalies on the surface from changes in the amount of reflected light. The lighting device has a long shape that is longer than the outer diameter of the winding yarn package and the longer direction is arranged at right angles to the axial direction of the winding yarn package. Two to six lighting devices are arranged in the axial direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for visually inspecting a wound yarn package and a method for producing a multifillant.

The winding yarn package produced in the fiber manufacturing factory may have defects such as dirt, fluff, and unwinding on the surface of the winding yarn package due to various causes. Therefore, the manufacturing plant inspects these defects in advance and manages to ship only the winding yarn package without the defects.

As a method for automatically inspecting various surface defects as described above, in Patent Document 1, the camera is arranged so as to scan the entire axial inspection width of the winding yarn package, and the output of each element of the camera is substantially uniform. A technique for inspecting by adjusting the amount of light of a plurality of light sources is disclosed.

In Patent Document 2, fluff protruding from the surface of the winding yarn package is photographed and detected by an area camera through a slit, and defects such as dirt, which are different in brightness from the normal part, are detected by a plurality of line cameras according to the winding shape of the winding yarn package. The technology for arranging and inspecting lighting is disclosed.

Japanese Unexamined Patent Publication No. 52-0855538 Japanese Unexamined Patent Publication No. 54-030943

However, since the technique described in Patent Document 1 uses illumination that irradiates in a radial pattern, it adheres to the surface of the winding yarn package and is small and dirty as if it extends along the winding direction and becomes linear. There is a problem that dirt is buried in the shadow of the unevenness of the winding thread and cannot be detected accurately.
With the technique described in Patent Document 2, defects protruding from the surface of the winding yarn package and large stains that change the brightness from the normal part of the winding can be detected, but they may stick to the surface of the winding or be buried in the surface layer. There is a problem that defects such as fluff and loops that do not protrude can not be detected because they are not captured by the area camera, and fine linear stains and small stains are buried in the shadow of the unevenness of the winding yarn and cannot be detected accurately. In addition, there is a problem that it is costly because a plurality of cameras are required depending on the winding shape.

An object of the present invention is to accurately detect stains and small stains that extend along the winding direction and become linear without being affected by the uneven shadows of the winding yarn, and also on the surface of the winding. It is an object of the present invention to provide a method for visually inspecting a wound yarn package and a method for producing a multifillant, which can accurately detect defects such as fluff and loops that do not stick or are buried in the surface layer and do not protrude.

1. 1. This is a method for inspecting the appearance of a winding yarn package in which a yarn is wound around a winding yarn tube. The surface of the winding yarn package rotating in the winding direction of the yarn is irradiated with light from a lighting device and reflected on the surface of the winding yarn package. The reflected light is received by the light receiving surface of the line sensor, and an abnormality on the surface is detected from the change in the amount of reflected light. A method for visually inspecting a wound yarn package in which two or more of the lighting devices are arranged at right angles to the axial direction of the yarn package and the two or more lighting devices are arranged in the axial direction.
2. This is a method for inspecting the appearance of a winding yarn package in which a yarn is wound around a winding yarn tube. The surface of the winding yarn package rotating in the winding direction of the yarn is irradiated with light from an illuminating device and reflected on the surface of the winding yarn package. The reflected light is received by the light receiving surface of the line sensor, and an abnormality on the surface is detected from the change in the amount of reflected light. A method for visually inspecting a wound yarn package in which 1 to 5 of the lighting measures are arranged in the axial direction and the illuminance is irradiating light of 50,000 Lx or more.
3. 3. The method for visual inspection of a winding yarn package according to 1 or 2, wherein the distance from the lighting device to the surface of the winding yarn package is 50 to 200 mm.
4. 2. The method for visual inspection of a winding yarn package according to 2 or 3, wherein the scanning line of the line sensor and the angle of the irradiation direction from the long illuminating device to the winding yarn package are 30 to 60 degrees.
5. The method for visual inspection of a wound yarn package according to any one of 2 to 4, wherein the irradiation device is a condensing bar illumination.
6. The method for visual inspection of a winding yarn package according to any one of 2 to 5, wherein the tapered portion of the winding yarn package is irradiated with light from a light source of an illuminating device arranged substantially parallel to the tapered portion.
7. The method for visual inspection of a winding yarn package according to 1 or 2, wherein an abnormality on the surface of an exposed winding yarn tube in which the yarn of the winding yarn package is not wound is also inspected at the same time.
8. The method for visual inspection of a winding yarn package according to any one of 1 to 7, wherein the rotation speed of the winding yarn package is 10 seconds / circumference or less.
A method for visually inspecting a wound yarn package, wherein the method for visually inspecting the wound yarn package according to 9.1 and 2 is performed at the same time.
10. A method for producing a multifilant, wherein the multifilant is spun, wound around a winding tube to form a winding package, and then the appearance inspection of the winding package according to any one of 1 to 9 is performed.

The effect of the present invention is to accurately detect stains and small stains that extend along the winding direction and become linear without being affected by the uneven shadows of the winding yarn, and also on the surface of the winding. It is possible to provide a method for visually inspecting a wound yarn package and a method for producing a multifillant, which can accurately detect defects such as fluff and loops that do not stick or are buried in the surface layer and do not protrude.

The schematic diagram which shows the apparatus for carrying out the appearance inspection method of the winding yarn package which concerns on claim 1 of this invention. The schematic diagram which shows the apparatus for carrying out the appearance inspection method of the winding yarn package which concerns on claim 2 of this invention. The schematic which shows the apparatus for carrying out the appearance inspection method of the winding yarn package which concerns on claim 9 of this invention. The schematic diagram which shows the apparatus for carrying out the appearance inspection method of the winding yarn package which concerns on Comparative Examples 1 and 2. Image of dirt extending along the direction of the winding taken in Example 1 and becoming linear Image of fluff that sticks to the surface of the roll and does not protrude, taken in Example 2. Image of dirt extending along the direction of the winding taken in Comparative Example 1 and becoming linear Image of fluff that sticks to the surface of the roll and does not protrude, taken in Comparative Example 2.

(First form of the present invention)
The method for inspecting the appearance of a wound yarn package of the present invention is a method for inspecting the appearance of a wound yarn package in which a yarn is wound around a wound yarn tube, and illuminates the surface of the wound yarn package rotating in the winding direction of the yarn with light from an illuminating device. The reflected light reflected on the surface of the winding yarn package is received by the light receiving surface of the line sensor, an abnormality on the surface is detected from the change in the amount of reflected light, and the lighting device has a length longer than the outer diameter of the winding yarn package. It has an elliptical shape, the elongated direction is arranged perpendicular to the axial direction of the winding yarn package, and two or more of the lighting devices are arranged in the axial direction.

The lighting device has a long shape that is longer than the outer diameter of the winding yarn package, and by arranging the long length direction at right angles to the axial direction of the winding yarn package, the shadows of the unevenness of the winding yarn are canceled and the winding is wound. It becomes possible to specifically photograph stains that extend along the direction and become linear or small stains with a brightness different from that of the normal portion. As a result, by setting a threshold value between the normal portion and the brightness difference between the defective portion such as dirt, the defective portion can be detected with high accuracy.
By arranging the two or more lighting devices in the axial direction, it is possible to detect the defect portion with high accuracy over the entire axial range of the winding yarn package. The upper limit is not particularly limited, but from the viewpoint of equipment, 6 or less is preferable.

The length of the luminaire in the long direction may be equal to or greater than the outer diameter of the winding yarn package, but the length of the illuminating device in the long direction is 1.2 times or more the outer diameter of the winding yarn package. It is preferable because it is easy to cancel the shadow of the unevenness, and 1.5 times or more is more preferable.

Regarding the placement position of the lighting device, it is preferable that the position is between the line sensor and the winding yarn package so as not to interfere with the scanning range of the licensor.

The number of lights to be arranged is selected according to the winding shape of the winding yarn package. For example, in the case of the pan shape shown in FIG. 1, four lights are arranged because there are a straight portion and a tapered portion. Further, if it is cheese-shaped, the number of tapered portions is small, so the number of lights to be arranged may be reduced.
When a plurality of lighting devices are arranged, it is preferable to arrange them at a position where the entire range can be evenly irradiated in the axial direction of the winding yarn package.
It is preferable that the center position of the plurality of lighting devices is the same as the position of the line camera.

By this visual inspection, it is possible to determine the stain on the surface of the winding yarn package and obtain only the winding yarn package without stains.
In the present invention, the yarn is a raw yarn of long fibers (filaments), a processed yarn, and a spun yarn.

(Second form of the present invention)
The method for inspecting the appearance of a wound yarn package of the present invention is a method for inspecting the appearance of a wound yarn package in which a thread is wound around a wound thread tube, and illuminates the surface of the wound thread package rotating in the winding direction of the thread with light from an illuminating device. The illuminating device has a long shape and is long by irradiating and receiving the reflected light reflected on the surface of the winding yarn package on the light receiving surface of the line sensor and detecting an abnormality on the surface from a change in the amount of reflected light. The direction is arranged parallel to the axial direction of the winding yarn package, and 1 to 5 of the lighting measures are arranged in the axial direction to irradiate light having an illuminance of 50,000 Lx or more.

The lighting device has a long shape, the long direction is arranged parallel to the axial direction of the winding yarn package, and 1 to 5 of the lighting measures are arranged in the axial direction, so that light is emitted in the normal part. However, if there is a defect such as fluff and there is a change in unevenness along the winding direction of the fiber, the scattered light is received by the line camera, so if there is a defect, the brightness will be higher than the normal part. Can be imaged in a high state.
By arranging 1 to 5 of the lighting measures in the axial direction, it is possible to irradiate the whole from the upper part to the lower part of the winding yarn package, and it becomes easy to find defects.
By irradiating light with an illuminance of 50,000 Lx or more, the light is strongly scattered even with small fluff or fluff buried in the surface layer, and it becomes possible to shoot with higher brightness than the normal part, and it becomes a constant brightness. By setting a threshold value and extracting a region higher than the threshold value, defects can be detected accurately.

The number of lights to be arranged is selected according to the winding shape of the winding yarn package. For example, in the case of the pan shape shown in FIG. 2, since there are a straight portion and a tapered portion, it is preferable to arrange three or more lights. Further, if it is a cheese shape, there are few tapered portions, so the illumination to be arranged may be one of the straight portions.

By this visual inspection, it is possible to discriminate fluff, collapse, scratches and stains on the winding yarn package, and obtain only a winding yarn package without fluff, collapse, scratches on the winding yarn pipe and stains.

In the method for visually inspecting the winding yarn package of the present invention, the distance from the lighting device to the surface of the winding yarn package is preferably 50 to 200 mm.
If the distance is 50 mm or more, contact with the device or the like can be avoided when the winding yarn package is conveyed, and if it is 200 mm or less, the surface of the winding yarn package can be illuminated with strong illuminance. can.
From these viewpoints, the distance is more preferably 100 to 150 mm.

In the visual inspection method of the winding yarn package of the present invention, the angle between the scanning line of the line sensor and the irradiation direction from the long lighting device to the winding yarn package is preferably 30 to 60 degrees.
When the angle is 30 degrees or more, it is possible to make it difficult for the scattered light in the normal part to enter the line sensor, and when it is 60 degrees or less, it is easy for the scattered light in the defective part such as fluff to enter the line sensor. can do.
An example of the angle is the angle shown in A in FIG.

In the method for inspecting the appearance of the wound yarn package of the present invention, it is preferable that the irradiation device is a condensing bar illumination.
Since the irradiation device is a condensing bar illumination, it makes it difficult for scattered light in the normal part to enter the line sensor, and makes it easy for the scattered light in the defective part such as fluff to enter the line sensor selectively, and has a good S / N ratio. You will be able to shoot.

In the method for inspecting the appearance of the winding yarn package of the present invention, it is preferable that the tapered portion of the winding yarn package is irradiated with light from a light source of an illuminating device arranged substantially parallel to the tapered portion.
By irradiating light from the light source of the lighting device arranged substantially parallel to the tapered portion, unevenness in the amount of light received by the line sensor is reduced, and defects can be photographed with a good S / N ratio.

A lighting device arranged substantially parallel to the tapered portion need only have less unevenness in the amount of light received by the line sensor, so it does not have to be completely parallel to the tapered portion and is appropriately adjusted according to the amount of light received by the line sensor. Just do it. It is preferable that the parallel deviation between the tapered portion and the illuminating device is within a range of ± 15 degrees.

In the method for inspecting the appearance of the winding yarn package of the present invention, the surface of the exposed winding yarn tube in which the yarn of the winding yarn package is not wound is also set as the irradiation range of the illumination and the imaging range of the line sensor, and the surface of the exposed winding yarn tube is set. It is preferable to inspect for abnormalities at the same time.

When the exposed winding tube is inspected at the same time, lighting that illuminates the exposed winding tube area may be installed individually if necessary.

Examples of abnormalities on the surface of the exposed winding yarn tube include scratches and dents caused by contact when handling the winding yarn package, machine oil adhering during the manufacturing process, and the like.

In the method for visually inspecting the winding yarn package of the present invention, the rotation speed of the winding yarn package is preferably 10 seconds / circumference or less.
If the rotation speed of the winding yarn package is 10 seconds / circumference or less, the inspection can be performed efficiently.
From this viewpoint, the rotation speed is preferably 8 seconds / lap or less, and more preferably 7 seconds / lap or less.
The lower limit of the rotation speed may be high as long as it can be inspected, but it is not necessary to increase the amount of light, and it is preferably 1 second / lap or more, more preferably 3 seconds / lap or more, and 4 seconds / lap. The above is more preferable.

In the method for inspecting the appearance of the wound yarn package of the present invention, it is preferable to carry out the first form and the second form at the same time.
By performing the first form and the second form at the same time, dirt or small dirt that extends along the winding direction and becomes linear and small fluff or fluff buried in the surface layer are detected at the same time. can do.

In the method for producing a multifilant of the present invention, the multifillant is spun, wound around a winding tube to form a wound yarn package, and then the appearance inspection of the wound yarn package is performed.
After making the winding yarn package, the appearance inspection of the winding yarn package is performed.
It is possible to obtain a winding yarn package without defects such as fluff, dirt, loops and dents.

(Example 1)
An acetate fiber winding package consisting of 20 filaments to be detected, which has two large and small black streaks that extend along the winding direction for which stains have been visually confirmed in advance. Using. The outer diameter of the thickest part of the winding yarn package was 160 mm.
As the lighting device, four white bar lights (CA-DBW24W manufactured by KEYENCE CORPORATION) having a length of 240 mm in the long direction were used. A CA-HL08MX manufactured by KEYENCE CORPORATION was used as the line sensor for receiving the reflected light, and an image sensor XG-X2900 manufactured by KEYENCE CORPORATION was used as a means for detecting an abnormality.
As shown in FIG. 1, a lighting device and a line sensor were arranged on the winding yarn package.

While rotating the winding yarn package at a speed of 6 seconds per revolution, the flow resolution along the rotation direction is about 0.1 mm and the width resolution in the longitudinal direction of the winding yarn package is set in the region where the outer diameter of the winding yarn package is the largest. Inspected at about 0.1 mm.

FIG. 5 shows the inspection results in the vicinity of two large and small black streaks that extend along the winding direction and become linear. A large stain was confirmed at the top of the image and a small stain was confirmed at the bottom left of the image. Further, by setting the region below the pixel average value of the captured image as a defective region, it was possible to automatically detect large and small stains with high accuracy.

(Example 2)
As a detection target, a wound yarn package of acetate fibers composed of 20 filaments, which had small fluff defects in which fluff defects were visually confirmed in advance, was used. This fluff defect exists in a state of being stuck to the surface of the winding and does not protrude from the surface of the winding yarn package. The outer diameter of the thickest part of the winding yarn package was 160 mm.
Condensing bar lighting (OPLS-200W, manufactured by OPTEX FA) was used as the lighting device. A CA-HL08MX manufactured by KEYENCE CORPORATION was used as the line sensor for receiving the reflected light, and an image sensor XG-X2900 manufactured by KEYENCE CORPORATION was used as a means for detecting an abnormality.
As shown in FIG. 2, a lighting device and a line sensor were arranged on the winding yarn package.

While rotating the winding yarn package at a speed of 6 seconds per revolution, the flow resolution along the rotation direction is about 0.1 mm and the width resolution in the longitudinal direction of the winding yarn package is set in the region where the outer diameter of the winding yarn package is the largest. Inspected at about 0.1 mm.

The inspection result near the fluff defect is shown in FIG. A small fluff defect can be seen in the center of the image. Further, by setting the region exceeding the pixel average value of the captured image as a defective region, it was possible to automatically detect the fluff defect with high accuracy.

Since this fluff defect does not protrude from the surface of the winding, it is a defect that cannot be detected by the projection type defect detection method of Patent Document 2.

(Comparative Example 1)
The same detection target as in Example 1 is used, the illumination is arranged parallel to the longitudinal direction of the winding yarn package as shown in FIG. 4, and the angle between the scanning line of the line sensor and the irradiation direction is 45 degrees. And took a picture.
A white bar illumination (CA-DBW50H, manufactured by KEYENCE CORPORATION) having a width of 520 mm was used as the illumination device. A CA-HL08MX manufactured by KEYENCE CORPORATION was used as the line sensor for receiving the reflected light, and an image sensor XG-X2900 manufactured by KEYENCE CORPORATION was used as a means for detecting an abnormality.

While rotating the winding yarn package at a speed of 6 seconds per revolution, the flow resolution along the rotation direction is about 0.1 mm and the width resolution in the longitudinal direction of the winding yarn package is set in the region where the outer diameter of the winding yarn package is the largest. Inspected at about 0.1 mm.

FIG. 7 shows the shooting results in the vicinity of two large and small black streaks that extend along the winding direction and become linear. Large stains could be confirmed at the top of the image, but small stains at the bottom left of the image were buried in the fiber winding pattern, and even if automatic detection was attempted, false detection of the fiber winding pattern would increase, and automatic detection could be performed with high accuracy. There wasn't.

(Comparative Example 2)
The inspection was carried out in the same manner as in Comparative Example 1 except that the same detection target as that used in Example 2 was used.

While rotating the winding yarn package at a speed of 6 seconds per revolution, the flow resolution along the rotation direction is about 0.1 mm and the width resolution in the longitudinal direction of the winding yarn package is set in the region where the outer diameter of the winding yarn package is the largest. The image was taken at about 0.1 mm.

FIG. 8 shows a photograph result in the vicinity of the fluff defect which is stuck to the surface of the winding and does not protrude. Although a slight fluff defect is shown in the center of the image, it is not clearly shown, so even if an attempt was made to automatically detect it, the number of false detections of the fiber winding pattern increased, and it was not possible to automatically detect it accurately.

1 Winding yarn package 2, 7, 8 Line sensor 3, 3', 4, 4', 5, 6, 6', 9 Lighting A angle

Claims (10)

This is a method for inspecting the appearance of a winding yarn package in which a yarn is wound around a winding yarn tube. The surface of the winding yarn package rotating in the winding direction of the yarn is irradiated with light from a lighting device and reflected on the surface of the winding yarn package. The reflected light is received by the light receiving surface of the line sensor, and an abnormality on the surface is detected from the change in the amount of reflected light. A method for visually inspecting a wound yarn package in which two or more of the lighting devices are arranged at right angles to the axial direction of the yarn package and the two or more lighting devices are arranged in the axial direction. This is a method for inspecting the appearance of a winding yarn package in which a yarn is wound around a winding yarn tube. The surface of the winding yarn package rotating in the winding direction of the yarn is irradiated with light from an illuminating device and reflected on the surface of the winding yarn package. The reflected light is received by the light receiving surface of the line sensor, an abnormality on the surface is detected from the change in the amount of reflected light, the illuminating device has a long shape, and the long direction is arranged parallel to the axial direction of the winding yarn package. A method for visually inspecting a wound yarn package in which 1 to 5 of the lighting measures are arranged in the axial direction and the illuminance is irradiating light of 50,000 Lx or more. The method for visual inspection of a winding yarn package according to claim 1 or 2, wherein the distance from the lighting device to the surface of the winding yarn package is 50 to 200 mm. The method for visual inspection of a winding yarn package according to claim 2 or 3, wherein the angle between the scanning line of the line sensor and the irradiation direction from the long lighting device to the winding yarn package is 30 to 60 degrees. The method for visual inspection of a wound yarn package according to any one of claims 2 to 4, wherein the irradiation device is a condensing bar illumination. The method for visual inspection of a winding yarn package according to any one of claims 2 to 5, wherein the tapered portion of the winding yarn package is irradiated with light from a light source of an illumination device arranged substantially parallel to the tapered portion. The method for visual inspection of a winding yarn package according to claim 1 or 2, wherein an abnormality on the surface of an exposed winding yarn tube in which the yarn of the winding yarn package is not wound is also inspected at the same time. The method for visually inspecting a wound yarn package according to any one of claims 1 to 7, wherein the rotation speed of the wound yarn package is 10 seconds / revolution or less. A method for visually inspecting a wound yarn package, wherein the method for visually inspecting the wound yarn package according to claims 1 and 2 is performed at the same time. A method for producing a multifilant, wherein the multifillant is spun, wound around a winding tube to form a wound yarn package, and then the appearance inspection of the wound yarn package according to any one of claims 1 to 9 is performed.

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