JP7525995B2 - Winding machine and device for identifying lint - Google Patents

Description

The present invention relates to
a light source configured to irradiate the spinning bobbin with infrared light;
an imaging unit for producing a digital image of the spinning bobbin tube;
an evaluation unit for evaluating the digital image in order to detect lint;
The present invention relates to an apparatus for identifying lint on a spinning bobbin tube, comprising:

The present invention further relates to a winding machine having a transport system for the spinning bobbin and the spinning bobbin tube, and a device for identifying thread waste on the spinning bobbin tube.

In the ring spinning machine, spinning bobbins with a relatively small yarn capacity are produced. The spinning bobbins are rewound into a large-capacity traverse package in the winding machine. The winding machine may have a transport system for the spinning bobbins and the spinning bobbin tubes. The transport system supplies the spinning bobbins to the individual winding units of the winding machine in an automated manner. The transport of the spinning bobbins takes place upright or vertically depending on the unwinding position in the winding unit. The spinning bobbins are arranged on a transport element. Such a transport element may be formed, for example, as a transport table with a plug-in mandrel for the spinning bobbins or the spinning bobbin tubes. The transport table can be transported inside the winding machine by means of a transport belt. After the yarn body has been unwound, the empty spinning bobbin tubes are discharged again from the transport system, also in an automated manner. The empty spinning bobbin tubes can be used in the ring spinning machine to produce new spinning bobbins. However, it may happen that the spinning bobbin is not completely unwound in the winding unit and the waste yarn remains on the spinning bobbin tube. The discharged spinning bobbin tube is therefore checked for waste yarn. The treatment of the spinning bobbin tube depends on the detected waste yarn. If the waste yarn is still usable, the spinning bobbin tube undergoes a bobbin preparation and is fed again to the winding unit. If the waste yarn is not usable, the spinning bobbin tube is fed to a tube cleaning section before reuse of the spinning bobbin tube in the ring spinning machine. Otherwise the waste yarn may cause problems during the spinning process and affect the formation of the bobbin.

DE 10 2014 016 784 A1 discloses the application of focused light for identifying lint on a spinning bobbin tube, where the optical axis of the light source forms an acute angle of between 2° and 8° with the axis of the spinning bobbin tube.

Here, it was shown that even with such an arrangement, in cases where the infrared-absorbing thread is colored, for example with soot, it is indistinguishable to the imaging unit.

DE 10 2014 016 784 A1

Therefore, the objective of the present invention is to improve the identification of infrared absorbing waste yarn on the spinning bobbin tube.

The object of the present invention is achieved by a device having the features of claim 1 and by a winding machine having the features of claim 12. Preferred developments of the invention are given in the dependent claims.

The device according to the invention for identifying yarn waste on a spinning bobbin tube is characterized in that the light source is arranged laterally spaced away from the spinning bobbin tube and the evaluation unit is configured to detect a contrast difference between the spinning bobbin tube and the yarn.

A uniform brightness distribution is achieved on the tube by the laterally spaced light source. In this case, "latently spaced light source" is understood to mean an arrangement in which the light source is adjacent to the side of the spinning bobbin tube, which is positioned upright in the device, and irradiates the spinning bobbin tube with infrared light from the side. The infrared light strikes the spinning bobbin tube and the lint evenly. The lint on the spinning bobbin tube is shadowed on the spinning bobbin tube and can be uniquely identified in the digital image of the spinning bobbin tube by means of their projection. By arranging the light source laterally, it is achieved that the lint generates an unambiguous projection on the spinning bobbin tube by the lint. This makes the lint stand out clearly from the spinning bobbin tube on the digital image.

An embodiment of the device according to the invention allows, in particular, the identification of threads on the basis of shadow detection, i.e. threads that absorb infrared light, for example very dark threads colored with soot, which do not reflect infrared light and therefore cannot otherwise be detected by the imaging unit. The lighting arrangement according to the invention and the evaluation of the digital images generated by the imaging unit therefore also allow, for example, the identification of so-called "carbon black threads". In this case, the evaluation device can be external or integrated into the imaging device.

Of importance to the invention is the illumination of the spinning bobbin tube by the light source in such a way that the tube is uniformly illuminated with infrared light from the side. According to a particularly preferred embodiment, it is provided for this purpose that the optical axis of the light source intersects with the longitudinal axis of the spinning bobbin tube at an angle of 35° to 90°, preferably 45° to 80°, particularly preferably 55° to 70°. The correspondingly inclined arrangement of the light source particularly ensures a uniform brightness distribution on the spinning bobbin tube, so that the shadows caused by the lint can be detected by the imaging unit with particularly high reliability.

The embodiment according to the invention also makes it possible to reliably detect infrared-absorbing waste in a particularly reliable manner. According to a further embodiment of the invention, it is envisaged that the device comprises an additional light source arranged above the spinning bobbin tube positioned upright in the device, which additional light source is configured to irradiate the spinning bobbin tube with light. The use of an additional light source, which can be replaced or switched as required and which emits particularly preferably focused light and whose optical axis forms an angle of between 2° and 8° with the axis of the spinning bobbin tube, makes it possible to identify infrared-reflecting waste as well as infrared-absorbing waste with the device. Due to the arrangement of the optical axis of the additional light source according to this preferred development of the invention, it is achieved that more light is reflected by the waste than by the spinning bobbin tube. As a result, the reflecting waste stands out clearly from the spinning bobbin tube on the digital image.

This preferred development of the invention therefore makes it possible to reliably identify both infrared-absorbing and infrared-reflecting lint. In this case, depending on the spinning bobbin tubes to be processed and the yarns arranged on them, the additional light source can alternatively be switched on or off as required, in order to ensure reliable identification of the lint in all such applications. When processing infrared-absorbing lint, the additional light source remains switched off, so that the spinning bobbin tube is illuminated by the light source in a defined manner.

The use of a light source already ensures a reliable brightness distribution on the spinning bobbin tube, which enables the imaging unit to reliably detect shadows on the spinning bobbin tube. However, according to a preferred development of the invention, it is provided that the imaging unit has an illumination body, which illuminates the spinning bobbin tube with light. The use of a second light source coupled to the imaging unit and provided by an illumination body particularly ensures reliable detection of lint on the spinning bobbin tube.

The invention is based on the fact that the infrared-absorbing lint on the spinning bobbin tube casts a shadow that can be identified as a contrast. In this case, according to a preferred development of the invention, it is assumed that the spinning bobbin tube has a contrasting surface for the infrared-absorbing lint. The use of a contrasting surface, for example a bright surface, with a high contrast for black threads, for example so-called "carbon black" threads, improves in a complementary manner the identification accuracy of the lint on the spinning head tube. The shadows caused by the lint can be detected particularly well on a contrasting surface, in particular on a bright, for example white, surface of the spinning bobbin tube.

According to a further preferred embodiment, the light source comprises a plurality of partial light sources, which may consist, for example, of three LEDs, each with its own lens. By means of a plurality of partial light sources, the illumination surface of the light source can be increased, whereby the uniform illumination of the spinning bobbin tube can be improved without a corresponding decrease in the identification accuracy.

According to a further embodiment of the invention, it is provided that the optical axis of the imaging device forms an angle between 30° and 50° with the axis of the spinning bobbin tube. In this range, there is the possibility of detecting the shadow on the spinning bobbin tube due to the lint with particularly high reliability. This increases the identification accuracy in a supplementary manner. Particularly preferably, in this case, the longitudinal axis of the spinning bobbin tube, the optical axis of the light source, the optical axis of the additional light source and/or the optical axis of the imaging device are in one plane. Corresponding embodiments, in particular in the case of an arrangement in which all the aforementioned axes are in one plane, allow for a particularly compact and reliable device construction. This device construction allows for a reliable identification of lint, in particular infrared-absorbing lint, in a space-saving manner.

The embodiment of the imaging device here can basically be selected arbitrarily. However, according to a particularly preferred embodiment, it is envisaged that the imaging device comprises at least one objective lens and an imaging sensor that are configured according to the camera specifications.

The evaluation device preferably comprises means for defining an evaluation window within the outer contour of the spinning bobbin tube, which evaluation window is evaluated with respect to the thread waste. Defining the evaluation window simplifies the detection of the thread waste. During the evaluation, it can be taken into account that the thread waste is basically always formed as a package thread. Other arrangements of the thread waste do not occur due to the winding scheme of the spinning bobbin, or at least are not dangerous for further processing. The detection of the outer contour of the spinning bobbin tube can be carried out by known edge filter methods.

The means for defining the evaluation window are in this case particularly preferably configured in such a way that, when the evaluation window is defined, an alignment of the evaluation window with the spinning bobbin tube is achieved. Thus, an angular misalignment between the evaluation window and the spinning bobbin tube is avoided from the outset.

Furthermore, there is also the possibility of defining a standard evaluation window, these means being configured to detect and correct angular deviations between the evaluation window and the spinning bobbin. Such angular deviations can easily occur in connection with conventional conveying systems that guide the bobbin into the device, particularly in the conveying direction. This means that the area of the standard evaluation window can be outside the outer contour of the spinning bobbin, which can therefore lead to evaluation errors without rotating the standard evaluation window in the direction of the spinning bobbin tube.

According to a further embodiment of the invention, it is assumed that a background is present, in front of which a digital image of the spinning bobbin tube can be detected. This can be achieved, for example, by the use of a predefined background, in particular a background with a pattern, which facilitates the detection of the outer contour of the spinning bobbin tube. This pattern, particularly preferably in the case of an embodiment as a checkerboard pattern, also facilitates the alignment of the spinning bobbin tube and thus the detection of the angular deviation with respect to the vertically arranged evaluation window. A pattern can also facilitate the alignment and initialization of the image capture device. According to an alternative embodiment of the invention, the background is illuminated, whereby the contrast between the background and the spinning bobbin tube is likewise improved. In this case, illumination is preferably performed from the side opposite the spinning bobbin, so that unwanted stray light does not enter the spinning bobbin tube. A further alternative embodiment is a background that includes a reflective film. This reflective film acts as a reflector that is illuminated by the illumination and thus generates a predefined white background in the image.

The object of the present invention is also achieved by a winding machine comprising a transport system for the spinning bobbin and the spinning bobbin tube and a device for identifying the thread waste on the discharged spinning bobbin tube, which is arranged along the transport path of the spinning bobbin tube, and which is configured in the above-mentioned embodiment according to the invention or according to one or more developments. In this case, according to the present invention, the light source is arranged laterally spaced from the spinning bobbin tube and the evaluation unit is configured to detect a contrast difference between the spinning bobbin tube and the thread.

Particularly preferably, the known transport system has a transport element in which the spinning bobbin and the spinning bobbin tube are transported upright. In the case of upright transport, the plane subtended by the axis of the spinning bobbin tube present in the device and the optical axis of the light source is preferably arranged perpendicular to the transport direction of the spinning bobbin tube. This allows the winding machine to be constructed in a particularly simple and compact manner, and furthermore, the spinning bobbin tube can be optimally transported into the device, where a digital image is generated during the passage.

According to a preferred development of the invention, it is further envisaged that the transport system preferably has means for stabilising the spinning bobbin tube standing upright on the transport element in a direction perpendicular to the transport direction when transporting the spinning bobbin tube upright in the area of the device. Such means prevent variations in the alignment of the spinning bobbin tube and allow a particularly accurate maintenance of the angle between the axis of the spinning bobbin tube and the optical axis of the light source. The stabilising means may, for example, be formed as a guide in the area of the tube tip.

Because stabilizing the spinning bobbin tube in the conveying direction is not easily achievable and because the conveying movement needs to be guaranteed, variations in the alignment of the spinning bobbin tube in the corresponding direction are preferably compensated for during the evaluation as described above.

Below, an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a schematic side view of a winding machine. 1 illustrates an embodiment of an apparatus for identifying infrared absorbing lint. A spinning bobbin tube in front of a background with a checkered pattern.

Figure 1 shows a winding machine 1 according to the invention. Between the end frames 5 and 6, several winding units 2 are arranged. In these winding units 2, the spinning bobbins 9 present at the unwinding position 10 are rewound into large-capacity traverse packages. The illustrated winding machine 1 includes a transport system 3 for the spinning bobbins 9 and the spinning bobbin tubes 4.

The spinning bobbin tube 4 as well as the spinning bobbin 9 are arranged upright on the transport table 8. The transport table 8 with the complete spinning bobbin 9 is transported from the rear side of the winding machine 1 to the winding unit 2 for unwinding. The spinning bobbin 9 is already in the upright position required for unwinding. A tube return section 7 is arranged on the front side of the winding machine 1. Via this tube return section 7, the empty spinning bobbin tube 4 (which is discharged from the winding unit 2 after unwinding) is transported still upright in the direction of the end frame 5.

It is also possible that the spinning bobbin 9 is not completely unwound and that the waste yarn remains on the spinning bobbin tube 4. This occurs, for example, when after a yarn break, no yarn end can be found on the spinning bobbin 9 and the incompletely unwound spinning bobbin 9 is discharged from the winding unit 2. In the area of the end frame 5, a device 11 for identifying the waste yarn is arranged. The further processing of the spinning bobbin tube 4 is carried out depending on the identified waste yarn. The spinning bobbin tube 4 that is completely unwound without waste yarn can be used for the production of new spinning bobbins 9 in the ring spinning machine without further processing. The spinning bobbin tube 4 with the still usable waste yarn is fed to a bobbin preparation device, not shown, which finds the yarn end and prepares the spinning bobbin tube 4 with the remaining wound part for further processing in the winding unit 2. In the case of unusable waste yarn, cleaning of the spinning bobbin tube 4 is necessary.

2 shows the basic structure of the device 11 shown in FIG. 1. As already explained, the spinning bobbin tube is guided to the device 11 on the transport table 8 by means of the transport system 3. The transport direction runs here perpendicular to the drawing plane shown in FIG. 2, in which the light source 12 and the camera 13 are also arranged. In the region of the tube tip, there may be a device (not shown) for stabilizing the spinning bobbin tube 4 perpendicular to the transport direction of the spinning bobbin tube 4. This device prevents the spinning bobbin tube 4 from fluctuating. In the example shown, the optical axis of the light source 12 intersects with the longitudinal axis 15 of the spinning bobbin tube 4 at an angle α of 63°. The light source 12 is arranged here at a distance from the spinning bobbin tube 4 to the side. The light source 12 emits infrared light, which is reliably shadowed by lint on the spinning bobbin tube 4.

A camera 13 with an objective lens and an imaging sensor creates a digital image of the spinning bobbin tube 4. The optical axis 17 of this camera or the optical axis of the camera's objective lens forms an angle β of 39° with the longitudinal axis 15 of the spinning bobbin tube 4. The light source 12 and the camera 13 lie in a plane perpendicular to the transport direction of the spinning bobbin tube 4.

The image of the spinning bobbin tube 4 is created in front of a background 18, which is illuminated by a light source 19, for example, located on the side of the background 18 opposite the spinning bobbin tube 4. Alternatively, the background may be generated by an illuminated reflector/reflective film.

To detect the lint, the production of only one image, which is produced as the spinning bobbin tube 4 passes, is sufficient. Preferably, the light source 12 is only activated at the moment when the image is produced. The evaluation of the digital image with respect to possible lint is carried out by means of an evaluation device 14. In this case, this evaluation unit 14 may form a unit with the camera 13 in a variant to the embodiment shown in FIG. 2.

The detection of the lint on the spinning bobbin tube 4 can be carried out by means of an evaluation window 22. This evaluation window 22 is preferably rectangular and is dimensioned such that it is inside the outer contour of the spinning bobbin tube 4. In the conveying direction of the spinning bobbin tube 4, depending on the conveying system, a fluctuation of the spinning bobbin tube 4 around the vertical direction of the spinning bobbin tube 4 can occur. The spinning bobbin tube 4 can therefore move outside the vertical evaluation window 22. In FIG. 3, the spinning bobbin tube 4 is placed in front of a background 18 with a check pattern 21. This check pattern 21 is oriented vertically or horizontally. The check pattern 21 makes it possible to clearly identify that the spinning bobbin tube 4 is displaced from the vertical position. The evaluation window 22 is first aligned with the check pattern 21. That is, the check pattern 21 allows easy detection of an angular deviation between the evaluation window 22 and the spinning bobbin tube 4. After detection, this angular deviation can be easily compensated for, so that the evaluation window 22 is again inside the outer contour of the spinning bobbin tube 4. Alternatively, the possibility arises to detect the outer contour of the spinning bobbin tube 4 in front of an illuminated white background or in front of a reflector background and to align the evaluation window 22 to the outer contour from the start. In this way, the variations of the spinning bobbin tube 4 can be easily compensated for.

REFERENCE NUMERALS 1 Winding machine 2 Winding unit 3 Conveying system 4 Spinning bobbin tube 5 End frame 6 End frame 7 Tube return section 8 Conveying platform 9 Spinning bobbin 10 Unwinding position 11 Device 12 Light source 13 Imaging device/camera 14 Evaluation device 15 Longitudinal axis 16 Optical axis (light source)
17 Optical axis (imaging device)
18 Background 19 Light source 21 Check pattern 22 Evaluation window

Claims (14)

a light source (12) configured to irradiate the spinning bobbin with infrared light;
an imaging unit (13) for producing a digital image of the spinning bobbin tube (4) ;
an evaluation unit (14) for evaluating the digital image in order to detect lint;
A device (11) for identifying lint on a spinning bobbin tube (4) , comprising:
The light source (12) is arranged laterally spaced apart from the spinning bobbin tube (4),
the evaluation unit (14) is configured to detect a contrast difference between the spinning bobbin tube (4) and the yarn waste ,
The spinning bobbin tube (4) has a contrasting surface for the lint that absorbs infrared radiation;
An apparatus (11) characterized in that 2. The device (11) according to claim 1, wherein the optical axis (16 ) of the light source (12) intersects with the longitudinal axis (15) of the spinning bobbin tube (4) at an angle (α) of 35° to 90°, preferably 45° to 80°, particularly preferably 55° to 70°. 3. The device (11) according to claim 2, further comprising an additional light source arranged above the spinning bobbin tube (4) positioned upright in the device (11) , the additional light source being adapted to irradiate the spinning bobbin tube ( 4 ) with light. 4. Apparatus (11) according to claim 3, wherein the optical axis (17) of the imaging unit ( 13) forms an angle (β) with the longitudinal axis (15) of the spinning bobbin tube (4) that is between 30 ° and 50°. 5. The device (11) according to claim 4, wherein the longitudinal axis (15) of the spinning bobbin tube ( 4 ) , the optical axis (16) of the light source (12), the optical axis of the additional light source and/or the optical axis (17) of the imaging unit (13) lie in one plane. 6. The device (11) according to claim 1 , wherein the imaging unit (13) comprises an illumination body for irradiating the spinning bobbin tube (4) with light. 7. The device (11) according to claim 1, wherein the light source (12) is formed from a plurality of partial light sources. The apparatus (11) according to any one of claims 1 to 7 , wherein the imaging unit (13) comprises an objective lens and an imaging sensor. 9. The device (11) according to claim 1, wherein the evaluation unit (14) comprises means for defining an evaluation window (22) inside the outer contour of the spinning bobbin tube ( 4 ), the evaluation window ( 22) being evaluated with respect to lint. 10. The device (11) according to any one of the preceding claims, further comprising a background (18) in front of which the digital image of the spinning bobbin tube ( 4 ) is detectable. A winding machine comprising a transport system for spinning bobbins and spinning bobbin tubes (4) and a device (11) arranged along the transport path of the spinning bobbin tubes (4 ) for identifying lint on the discharged spinning bobbin tubes (4) ,
A winding machine, characterized in that the device (11) is constructed according to any one of claims 1 to 10 . 12. Winding machine according to claim 11 , characterized in that the transport system comprises a transport element (8) along which the spinning bobbins and the spinning bobbin tubes (4) are transported upright. 13. Winding machine according to claim 12, characterized in that the transport system comprises means in the area of the device ( 11 ) for stabilising the spinning bobbin tubes (4) standing upright on the transport elements (8) in a direction perpendicular to the transport direction. 14. Winding machine according to claim 11, characterized in that the plane subtended by the longitudinal axis (15) of the spinning bobbin tube (4) lying upright in the device ( 11 ) and the optical axis (16) of the light source (12) is arranged perpendicular to the conveying direction of the spinning bobbin tube (4).