Inspection device, use, pretreatment machine, device and method for detecting foreign matter in fibrous material

Abstract

The invention relates to an inspection device (30) for detecting foreign matters in a fibrous material which is accommodated in a pre-treatment machine (1; the invention relates to an inspection device (30) in a pretreatment machine (100), in particular a feed box (2) of a textile preparation machine, the inspection device (30) comprising: an opening closing device (31) for closing a housing opening (27) of the pretreatment machine (100), by means of which the feed box (2) can be seen from the outside, the opening closing device (31) having a separating element (32) and a cover element (33) arranged on the separating element (32), the separating element (32) has a transparent viewing region (39) defining a viewing plane (E), an interior space (37) being formed between the separating element (32) and the cover element (33); and a camera device (38) arranged in the interior (37), characterized in that an optical axis (40) of the camera device (38) is oriented at least substantially parallel to the observation plane (E), and in that a deflection device (41) is arranged in the interior (37) of the opening closing device (31), said deflection device deflecting a beam path (42) originating from the observation region (39) towards the camera device (38). The invention also relates to the use of the inspection device, to a pretreatment machine, to a device having a plurality of pretreatment machines, and to a method for optically inspecting a fibrous material.

Description

Technical Field

[0001] The invention relates to an inspection device for detecting foreign bodies in fiber material, which is contained in a cotton feed box of a pretreatment machine, in particular a textile preparation machine. The inspection device comprises an opening closing device for closing a housing opening of the pretreatment machine, through which the cotton feed box is visible from the outside. The opening closing device comprises a partition element and a cover element arranged on the partition element, the partition element having a transparent observation area defining an observation plane, wherein an inner space is formed between the partition element and the cover element. A camera device is arranged in the inner space. The invention also relates to the use of the inspection device, a pretreatment machine, an apparatus having a plurality of pretreatment machines and a method for detecting foreign bodies in fiber material. Background Art

[0002] In spinning mills, the fiber quality of purchased fiber bales (e.g. made of cotton, polyester, blended fibers, etc.) is known. However, it is quite difficult to infer the yarn quality from the quality of fiber samples in the cleaning room. Quality fluctuations in fiber bale samples are often not recognized during continuous processing and the necessary machine adjustments cannot be adapted so that the best yarn quality can always be obtained despite quality fluctuations. Among the multiple possible raw material parameters of fiber materials, the detection of foreign matter content or interfering particle content is a common parameter. Foreign matter present in compressed fiber bales is, for example, plant components such as stems, leaves, seeds (often also called "garbage"), or packaging residues such as cloth, fabric, film, plastic tape, etc. Among these foreign matter, only plant foreign matter (garbage) is detected in the raw material parameters of the purchased fiber bales. Other components, due to their relatively low frequency, can hardly be detected by traditional sampling using laboratory analysis instruments. In addition, the actual content fluctuates greatly. However, even for the content of vegetable components, the actual raw material quality differs significantly from the classification value and, in view of the quality requirements of the end product, also taking into account the use of energy and resource-saving handling of the raw materials, requires a modified adjustment of the pretreatment machine. In practice, however, readjustment of the machine due to fluctuations in the raw material quality is not possible, because the available measurement methods by experimental analysis are too slow to generate the corresponding control variables at an early stage, that is, during the material processing, or are associated with considerable expenditure.

[0003] DE 10 2019 115 138 discloses a sensor which can also automatically determine the foreign matter content in the carding machine web during operation. The sensor provides quality data after the last critical processing step of carding. The foreign matter content determined there is very suitable for describing the quality of the yarn produced subsequently, but it detects neither the current quality of the raw material provided nor the quality of the fiber material in the preceding intermediate steps such as pre-cleaning, mixing, cleaning, opening and foreign matter separation. If there are quality problems here, it is not clear whether they are caused in the raw material step or in one of the preceding process steps.

[0004] EP3951033A1 describes a method of sampling at the cleaning point of a variety of textile preparation machines. Through a network consisting of pipes and locking mechanisms, the waste accumulated at the cleaning point is sucked away and transported out through a transport pipeline to a central container equipped with a weighing device. The camera is aimed at the weighing device. The weighing device and the camera as well as the fan and the locking mechanism are connected to a control device. Through the control device, the waste begins to be transferred from the cleaning point. For this purpose, the corresponding locking mechanism at the connection of the corresponding cleaning point (for example, at the coarse filter) should be opened, and the fan should be turned on. The waste of the coarse filter should be sucked into the central container through the transport pipeline, released by the transport gas and filled into the weighing device. After filling the weighing device, the locking mechanism is closed again, and the waste is weighed and optically detected by the camera. In this way, different cleaning points should be emptied in turn and the waste sucked therefrom should be transported to the central container. The waste composition should be analyzed with the help of a camera so that the adjustment of the corresponding spinning preparation machine can be adapted or optimized accordingly.

[0005] It is considered disadvantageous that periodic sampling allows only a few sample variables per textile preparation machine and does not allow continuous monitoring. Furthermore, the waste composition does not allow any conclusions to be drawn about the incoming quality of the raw material. Furthermore, the project and assembly costs of the multiple pipes, the closing mechanisms and the control devices required for this are also considered disadvantageous, which obviously need to be carried out again for each spinning installation with a separate machine train.

[0006] EP 3951032 A1 describes a device with a camera for detecting interfering particles in fiber material collected in a feed box of a textile preparation machine. The camera is arranged at an angle of up to + / -30 degrees relative to a vertical line directed to the fiber surface. The arrangement of the camera's line of sight at least substantially perpendicular to the fiber material represents an arrangement that is advantageous and easy to implement for the sensor device and the evaluation, but this results in disadvantages in terms of accessibility to the textile preparation machine. Summary of the invention

[0007] The object of the present invention is to provide an inspection device, the use of such an inspection device in a pretreatment machine, a pretreatment machine having such an inspection device, an apparatus having a plurality of such pretreatment machines, and a method, by means of which the detection of foreign bodies in fiber materials can be further optimized.

[0008] This object is achieved by an inspection device of the aforementioned type in that the optical axis of the camera device is oriented at least substantially parallel to the observation plane and a deflection device is arranged in the interior of the opening closing device, which deflects a light path originating from the observation area toward the camera device.

[0009] The advantage lies in the flat structural form of the inspection device. The inspection device can therefore be installed in a simple manner in the housing opening without protruding in a disruptive manner. Since the camera device is not aimed directly at the observation area, but the deflection device deflects or folds the light path, the camera device can be arranged at a small distance relative to the observation plane. Therefore, the extension extending perpendicular to the observation plane, i.e. the depth of the inspection device, can be designed to be as small as possible. In addition, since the light path is deflected by the deflection device, the path between the camera device and the observation area is extended, thereby expanding the detection area without increasing the structural depth. With the help of the camera device, the fiber material passing through the inspection device can be optically inspected from the outside (i.e. outside the cotton feeding box) through a transparent observation area in order to determine quality characteristics, in particular the foreign matter content and thus be able to identify quality fluctuations more quickly. Sampling from the fiber material is thus omitted.

[0010] Here, “at least substantially parallel” should mean that the optical axis can be oriented in a preferred manner parallel to the observation plane, wherein deviations from parallelism within a range of plus 15 degrees to minus 15 degrees should also be included. In the case of deviations from parallelism, the intersection point of the optical axis with the observation plane can lie outside the observation area, so that the camera device is not directly aligned with the observation area, but always observes the observation area via the deflection device.

[0011] The camera device and the deflection device are preferably completely arranged in the inner space of the opening closing device. The cover element is arranged on the partition element and thus protectively covers the camera device arranged between the partition element and the cover element outwardly. Preferably, the cover element and the partition element are fixedly connected to each other. The partition element can be designed to be planar, wherein the design of the partition element preferably corresponds to the shape and contour of the housing wall surrounding the housing opening in order to ensure smooth passage of the fiber material. The partition element can also be called a partition wall. The cover element can be designed, for example, to be basin-shaped or bowl-shaped to form the inner space.

[0012] The deflection device can have a reflective surface. The angle of incidence or the angle of emergence between the optical path and the surface normal of the reflective surface can both be 45 degrees. This arrangement is particularly advantageous when the optical axis of the camera device is oriented parallel to the observation plane. Alternatively, the angle of incidence or the angle of emergence can be greater than 45 degrees and more preferably greater than 50 degrees and in particular less than 85 degrees, respectively. This allows the camera device to be brought closer to the partition element, thereby providing a flatter inspection device. Depending on the orientation, the angle of incidence or the angle of emergence can also be less than 45 degrees and in particular greater than 15 degrees. Although a slightly greater structural depth is achieved in this way, it also brings about a greater distance between the camera device and the observation area, thereby increasing the detection area of ​​the camera device. The deflection device can include at least one deflection element, in particular a mirror, wherein an optical waveguide or the like can be provided as an alternative to the mirror or as another deflection element.

[0013] An illumination device can be arranged in the inner space of the opening closing device for illuminating the fiber material passing through the observation area. This improves the image quality. The illumination device can extend over the entire width of the observation area. In particular, the illumination device can include a plurality of light emitting diodes or LED light sources, which can have lenses so as to evenly distribute the light emitted from the individual light emitting diodes. In addition, the illumination device can have a lower illumination element, wherein the deflection device is arranged between the camera device and the lower illumination element, as viewed along the optical axis. In addition to or as an alternative to the lower illumination element, the illumination device can have an upper illumination element, wherein the upper illumination element is arranged between the camera device and the deflection device. For example, the upper illumination element and / or the lower illumination element can both be designed in the form of a light strip or an LED strip.

[0014] In order to avoid light reflections on the image captured by the camera device, at least one lighting element directed toward the observation area can be arranged at an angle of incidence that deviates significantly from the surface normal of the observation plane. This is particularly suitable if two lighting elements are arranged both above the observation area and below the observation area. It is also possible that the angle of incidence of the lighting elements can also be directed perpendicularly to the observation plane. This is particularly advantageous when the light path between the observation area and the deflection device is inclined relative to the surface normal.

[0015] The observation area can be illuminated by means of the lighting device at least while the image is being recorded. In a further development, the observation area can be permanently illuminated by means of the lighting device. This is advantageous, among other things, when the camera device comprises a line scan camera. Likewise, a flash pattern in which the flash is generated by the lighting device can also be advantageous in the following cases: in order to detect different types of foreign bodies, light of different wavelengths should be illuminated alternately or the movement of the fiber material along the observation area is so slow that no light is required between the individual image recordings.

[0016] In particular, the camera device has at least one camera. The deflection device turns the light path from the observation area to the at least one camera. In addition, the number of cameras used depends on the width of the observation area, the maximum detection width of each camera, the size of the interior space, the distance between the camera device and the observation area, etc. Preferably, the camera device includes exactly one or two cameras. In order to increase the detection width of each camera, the camera can be placed as upward as possible in the interior space. In addition, the focal length of the lens can be reduced. However, this may result in a large viewing angle toward the edge of the detection area, which may be associated with optical disadvantages. When using a plurality of such cameras, these cameras can be arranged side by side and in particular spaced apart from each other in the width direction of the partition element. Here, the detection areas of adjacent cameras can also overlap to ensure gapless coverage of the observation area.

[0017] Furthermore, the camera device can include an evaluation unit, also referred to as an image evaluation computer, for analyzing the image data of the associated camera device. The evaluation unit is preferably arranged in the interior space. However, it is also possible in principle that the evaluation unit can also be arranged outside the interior space and, for example, be arranged on or in the pretreatment machine. The evaluation unit analyzes the image data received by the camera device and provides its evaluation result in the form of at least one output value, which can be used, for example, by a control unit of the pretreatment machine and / or a textile preparation machine upstream or downstream of the pretreatment machine in order to adjust machine elements that influence the degree of cleaning of the corresponding machine. In this way, the cleaning efficiency can be optimized by the recognition of the changing foreign matter content in the fiber material.

[0018] At least one of the cameras can be a line array camera. This enables detection of a large detection width or a large viewing angle along a line array, which can be oriented along the width of the observation area or the width direction of the housing opening. The line array camera captures images line by line. The individual image lines can be combined into a continuous image by an evaluation unit. The fiber material moves through the observation area and the camera device is fixedly held on the opening closing device, i.e. the camera remains stationary. The detection area, i.e. the image field during the shooting, is a slit of the width of the desired image, which preferably corresponds to the width of the partition element at most. As a result, the line array camera requires only a very small structural depth, so that on the one hand the deflection device can be arranged close to the partition element and the opening closing device can be designed as a flat structure as a whole. In addition, the observation area can be narrow in height and correspondingly wide in width. In order to avoid optical disadvantages caused by large viewing angles at the edges, it is advantageous that the viewing angle from the center of the camera to the edge of the image is, in particular, a maximum of 15 degrees. In a typical opening closing device for a cotton cleaning machine, a cotton blending machine, etc., the optical path or the entire optical path length can reach at least about 550 mm. Thus, an observation area of ​​at least about 300 mm wide and 0.3 mm high can be covered.

[0019] In principle, the at least one camera can also be an area scan camera or a matrix camera and it is likewise possible that the camera arrangement comprises a combination of at least one line scan camera and at least one area scan camera or a matrix camera. Each camera can have at least one image sensor and one lens in a manner known per se. The deflection device has a deflection element for each camera, wherein in principle a continuous deflection element can also be provided, to which the camera can be aligned.

[0020] Furthermore, the opening closing device can have an upper section and a lower section spaced apart from the upper section. The camera device can be arranged in the upper section and the viewing area and the deflection device can be arranged in the lower section, or vice versa. In order to increase the distance between the camera device and the deflection device and the viewing surface as a whole, further components can be arranged successively in the depth of the interior space, such as an evaluation unit, a control unit, etc. for determining the quality of the raw material, in particular for detecting foreign objects, in particular for detecting foreign objects with brightness deviations and / or color deviations. In particular, the evaluation unit and / or the control unit can be arranged between the camera device and the cover element.

[0021] In order to isolate the observation area from ambient light or extraneous light, the cover element can be designed to be light-proof in the section (especially the lower section or the upper section) where the observation area is located. This can avoid disturbing light reflections in the observation area.

[0022] In addition, the opening closing device can have a visible section located above the observation area and / or below the observation area. In other words, the observation area (in which the cover element can be designed to be opaque) is located outside the visible section. In the visible section, the partition element and the cover element can be constructed to be transparent. In particular, the visible section is arranged between the upper section and the lower section. Preferably, the visible section is directly adjacent to the upper section upward and directly adjacent to the lower section downward. In this way, the inspection device not only provides the possibility of optically inspecting the fiber material with the help of a camera device, but can also be used as an observation opening, through which the operator can see from the outside into the cotton feeding box of the pretreatment machine in order to view the fiber material passing through the partition element of the opening closing device. In principle, the visible section can also be an upper section, in which a camera device can be arranged, or it can extend over the middle section and the upper section. In addition, the entire cover element can also be designed to be transparent, for example, it can be made of a transparent glass material or plastic material. At the height of the viewing area, in particular in the lower section of the opening closure, the cover element made of a transparent material can be coated, painted or similarly treated in order to shield the viewing area from disturbing external light.

[0023] The opening closing device can be a carrier of other auxiliary sensor mechanisms. In particular, an idling monitoring device of the cotton feeding box can be arranged on the outer side of the partition element and / or in the inner space of the opening closing device. For example, this can include a grating or a photoelectric switch.

[0024] Furthermore, the opening closing device can include a frame which surrounds the partition element and the cover element. Thus, the opening closing device can be inserted into the housing opening, for example, like a rigid window sash. Furthermore, hinge means can be provided for pivotably fastening the opening closing device, in particular the frame, to the housing of the pretreatment machine in the region of the housing opening. Thus, the opening closing device can be designed to be inserted into the housing opening like a pivotable window sash, a pivotable door leaf, a pivotable flap, etc. Instead of an articulated arrangement, the opening closing device can also be inserted into the housing opening rigidly or immovably, for example like a rigid window.

[0025] Preferably, the inspection device can be operated as a structural unit, which can be installed in a housing opening like a window, a door or the like. Therefore, the inspection device can be called an intelligent maintenance door or an intelligent maintenance window. In order to operate the inspection device, the inspection device can be connected to a power supply, in particular a power supply of a pretreatment machine. In addition, means for data transmission can be provided.

[0026] For example, the camera device can have an interface for connecting to an evaluation unit and / or a control unit. The inspection device can include an evaluation unit, which can be arranged in particular in the interior of the opening closure device. The control unit can be a control unit of a pretreatment machine or a higher-level device control device.

[0027] The maintenance window that can be replaced by the inspection device usually has an outer width of at least approximately 400 mm and an outer height of at least approximately 800 mm. Preferably, the outer dimensions of the inspection device are selected such that the inspection device can be inserted into an existing housing opening instead of the maintenance window. In particular, the inspection device, in particular the opening closing device, can have an outer width of 200 mm to 600 mm and an outer height of 400 mm to 1200 mm. Preferably, the outer width is in the range of 300 mm to 500 mm, and the outer height is in the range of 600 mm to 1000 mm.

[0028] Another solution to the above-mentioned object consists in using the aforementioned inspection device to close a housing opening already present in a pre-treatment machine, through which a feeding box for the fiber material can be seen from the outside. The same advantages as those associated with the inspection device according to the invention can be achieved by the use according to the invention, so that reference is briefly made to the above description. It goes without saying that all the embodiments mentioned can be transferred to this use and vice versa.

[0029] The use according to the invention is based on the basic idea that conventional pre-treatment machines always have at least one housing opening, into which a viewing window or the like is usually built, through which the operator can look from the outside into the cotton feed box. According to the invention, an inspection device is built into the already existing housing opening instead of the conventional viewing window.

[0030] Preferably, the inspection device is used on a pretreatment machine in whose feeding box the fiber material is at least temporarily deposited. The fiber material can then be slowly passed through the inspection device, wherein a particularly brief rest of the fiber material is acceptable. This optimizes the detection of quality data, such as the foreign matter content. The fiber material can be present in the feeding box in a flocculent state.

[0031] Another solution to the above-mentioned object is a pretreatment machine having a housing which surrounds at least one feeding box for the fiber material and has at least one housing opening through which the feeding box is visible from the outside, and at least one aforementioned inspection device which is inserted into at least one of the at least one housing opening. The same advantages as the inspection device or use according to the invention can be achieved by the pretreatment machine according to the invention, so that reference is briefly made to the above description. It goes without saying that all the embodiments mentioned can be transferred to the pretreatment machine and vice versa.

[0032] The pretreatment machine can be a textile preparation machine, in particular a bale grabber (e.g. Truetzschler universal bale grabber BO-U), a cotton cleaner (e.g. Truetzschler universal cotton cleaner CL-U), an opener (e.g. Truetzschler universal opener TO-U), a blender (e.g. Truetzschler universal blender MX-U), a flake blender (e.g. Truetzschler T-Blend), a flat carding machine (e.g. Truetzschler TC21), etc. In addition, the pretreatment machine can also come from the field of nonwoven fabric production, such as an opener (e.g. Truetzschler universal fine opener TBL-FB or TBL-FO), a blending chamber (e.g. Truetzschler TBL-BB), a roller carding machine (e.g. Truetzschler TWF-NC), etc.

[0033] When such a pretreatment machine is in operation, the fiber material slowly passes the outside of the partition element. In particular, the feeding box is a feeding box with a metering device arranged on its bottom side so that the fiber material can be taken out of the feeding box in a quantitative manner. The metering device can be, for example, a roller feed part and / or an opening roller. In the feeding box, the transport speed of the fiber material when passing through the observation area is in the range of a few millimeters per minute to a few centimeters per minute. Typically, the transport speed is in the range of 20 millimeters per minute to 800 millimeters per minute. Brief stops of the material flow of the fiber material are also possible. In order to optimize the recognition of quality characteristics (such as foreign matter content) at slow transport speeds, it may be advantageous to equip the pretreatment machine with a plurality of inspection devices. In particular, each feeding box can be provided with two of the inspection devices, which are arranged facing each other on the front and rear side of the pretreatment machine.

[0034] In addition, a pressure sensor can be arranged in at least one cotton feeding box for measuring the dynamic pressure. With the help of the measured dynamic pressure, the output value of the evaluation unit can be corrected to a characteristic variable that is independent of the dynamic pressure. For this purpose, a calibration curve can be stored in the evaluation unit. Because the number of foreign bodies visible in the observation area or in the image captured by the camera device depends to a large extent on the material resolution of the fiber material. A loose material layer with good resolution will present a smaller number of foreign bodies to the camera device in the cotton feeding box. On the contrary, if the material in the cotton feeding box is compressed with a higher pressure by the loading of the transport air, significantly more foreign bodies will be displayed in the observation area or in the image and therefore in such a plane. Therefore, the fluctuating dynamic pressure may significantly affect the detection of the foreign body content. The at least one pressure sensor can be arranged above the specified maximum material level of the at least one cotton feeding box. The at least one inspection device can be arranged below the maximum material level. In order to specify the maximum material level, a grating or a photoelectric switch can be arranged in the at least one cotton feeding box. The maximum material level can be determined by the installation height of the grating or the photoelectric switch.

[0035] Another solution to the above-mentioned object is a device which comprises a plurality of the above-mentioned pretreatment machines. The same advantages as those associated with the inspection device or the application or the pretreatment machine according to the invention can be achieved by the device according to the invention, so that reference is briefly made to the above description. It goes without saying that all the embodiments mentioned can be transferred to the device and vice versa.

[0036] In this way, within the plant, a plurality of pretreatment machines, in particular all machines, are each equipped with at least one checking device. Thus, defined quality characteristics of the fiber material, such as the foreign matter content, can be analyzed at a plurality of process points within the plant. As a result, the subsequent machines can automatically adapt to changes in the raw material quality, depending on the detected raw material quality. In other words, for the automatic optimization of the plant, checking devices are provided, which analyze the fiber material in the receiving space of the pretreatment machine with respect to specified quality characteristics, such as the foreign matter content, also called interfering particle content, so that, depending on the detected quality characteristics, upstream and / or downstream textile preparation machines can automatically adapt to changes in the raw material quality.

[0037] The pretreatment machines of the plant cover the processing lines in the textile preparation in a targeted manner, so that the plant can include different types of pretreatment machines. In this way, the quality of the fiber material can be detected at multiple process points in the processing line, so that changing raw material qualities can be responded to during the processing by adapting the adjustment of the pretreatment machines.

[0038] Furthermore, it can be provided that at least one pretreatment machine or device has at least one waste sensor device, which is configured to analyze the waste composition of the waste separated from the fiber material, which contains foreign matter and good fibers, by means of at least one optical sensor. By integrating the waste sensor device into the pretreatment machine, it can be distinguished whether the raw material quality has deteriorated or whether the cleaning efficiency of the pretreatment machine has decreased. The quality of the raw material is monitored by means of the inspection device, while the waste sensor device monitors the waste composition.

[0039] For example, such a waste sensor device is known from patent document DE10349407B4. The at least one optical sensor can be arranged in a waste pipe, in particular in a waste pipe of a pre-processing machine. The at least one optical sensor can determine the frequency of material separation, i.e., the waste composition and can distinguish between desired waste (foreign matter) and undesired waste (fiber). Preferably, the pre-processing machine can automatically adjust the machine elements or cleaning elements that affect waste separation. For example, in a pre-cotton cleaning machine, the influence on waste separation can be the rotation speed of the opening roller or the opening width of the separation grid. In addition, adjustable separation blades, adjustable blades, suction hoods, etc. attached tangentially to the opening roller are also possible. In addition, the pre-processing machine can also be equipped with a plurality of other adjustable cleaning elements.

[0040] Another solution to the above-mentioned object is a method for optically inspecting fiber materials in a pretreatment machine described above or in an apparatus described above, wherein the method comprises the following steps: recording an image of the fiber material or its fiber material surface passing through an observation area by means of a camera device of a corresponding inspection device; evaluating the recorded image by at least one evaluation unit to determine quality characteristics of the fiber material, in particular the current foreign matter content; outputting an output value, which in particular includes the current foreign matter content in the fiber material. The method according to the invention achieves the same advantages as those associated with the inspection device or the use or pretreatment machine or apparatus according to the invention, so that reference is briefly made to the above description here. It goes without saying that all the embodiments mentioned can be transferred to the method and vice versa.

[0041] The images can be generated at successive time intervals. Furthermore, the method can comprise at least one of the following steps: comparing the output value with at least one specified and / or previous initial value, in particular the foreign matter content; determining the current waste composition by means of the at least one waste sensor device when the output value is outside a defined range around the at least one specified and / or previous initial value; comparing the current waste composition with a specified and / or previous waste value. The defined range can be zero, so that any deviation from the initial value triggers the determination of the current waste composition. Likewise, the range can also correspond to a percentage deviation of, for example, plus or minus 10%, wherein a larger or smaller range can also be adjusted depending on the operator's requirements for the pretreatment machine.

[0042] Furthermore, the method can also comprise the step of automatically changing the setting of at least one cleaning element or of at least one machine element of the respective pretreatment machine and / or of the textile preparation machine downstream of the respective pretreatment machine and / or of the textile preparation machine upstream of the respective pretreatment machine, which influences the waste separation, when the output value is outside a defined range around the at least one specified and / or previous initial value and / or when the current waste composition deviates from a specified and / or previous waste value. This enables particularly effective regulation of quality fluctuations, in particular when the foreign matter content in the raw material varies. Analogously to the above, the respective defined range can be zero or correspond to a percentage deviation of, for example, plus or minus 10%, wherein larger or smaller ranges are also adjustable depending on the operator's requirements for the pretreatment machine.

[0043] It is assumed merely by way of example that during the operation of the pretreatment machine, the raw material quality decreases on the one hand and the cleaning efficiency of the pretreatment machine decreases on the other hand, so that without a checking device, the decrease in raw material quality remains unnoticed. Another case is that the number of foreign bodies discharged from the cleaning site decreases, which can be determined by measuring the waste composition. However, it cannot be deduced from this whether the raw material has become cleaner or whether one of the pretreatment machines, in particular the cotton cleaning machine, must be reoptimized. Preferably, the waste sensor device is configured to perform an optimization operation when a change in the raw material quality is detected by the at least one checking device. The optimal adjustment thus depends on the material and the contaminants and can be adapted during operation when the raw material properties change.

[0044] The waste sensor device can be configured to perform an optimized operation, in which at least one cleaning element is gradually moved to a second terminal position for separating impurities and fibers at a first terminal position where impurities are not separated. Because the cleaning effect of the pre-treatment machine depends on the adjustment of its cleaning element. The sensor signal is detected and evaluated. Starting from the point where too much fiber material is disproportionately separated relative to the foreign matter content, the optimized operation can end. For example, in a cotton cleaning machine such as the cotton cleaning machine CL-U of Truetzschler, the first cleaning element can be tangentially moved in the form of a blade, so that the cleaning point can be opened or completely or partially closed. The second cleaning element, which can be a pivotable blade, can rotate around its rotation center, so that the cleaning point can also be opened or completely or partially closed here. In this way, only a slight or no cleaning effect is achieved at the first terminal position, and at the second terminal position, although the cleaning effect may be better, in addition to foreign matter, too many good fibers may also arrive in the waste together. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Other features and advantages of the present invention are apparent from the following description of preferred embodiments. In which substantially or functionally identical or similar features are provided with the same reference numerals. In the figures:

[0046] Figure 1 A schematically simplified representation of a pretreatment machine according to a first specific embodiment of the invention is shown, wherein the pretreatment machine comprises an inspection device according to the invention having a camera, a deflection device and two illumination elements;

[0047] Figure 2 showing a side view, partially cut away, of a pre-processing machine;

[0048] Figure 3 An enlarged partial view of a pretreatment machine is shown in a schematically simplified sectional view;

[0049] Figure 4An enlarged detail view of a pretreatment machine in the area of ​​an inspection device is shown, wherein a camera is adjusted to a first focal length;

[0050] Figure 5 Show Figure 4 an enlarged partial view of the camera, wherein the camera is adjusted to a second focal length;

[0051] Figure 6 A schematic diagram showing a flow chart of a pre-processing machine when operating automatically;

[0052] Figure 7 Show Figure 6 A schematic diagram of a sub-step of a flow chart in which the sub-step involves determining the foreign matter content in a fiber material;

[0053] Figure 8 Show Figure 6 a schematic diagram of another sub-step of the flowchart in , the sub-step involving performing an optimization run;

[0054] Fig. 9 An enlarged partial view of a pretreatment machine according to an alternative embodiment is shown in a schematically simplified sectional view, wherein the pretreatment machine comprises a plurality of inspection devices;

[0055] Fig.10 shows an enlarged detail of a pretreatment machine in the area of ​​a testing device according to an alternative embodiment with two cameras;

[0056] Fig.11 An enlarged detail of a pretreatment machine according to another embodiment is shown in a schematically simplified sectional view;

[0057] Fig.12 A side view of a pretreatment machine according to another embodiment of the invention is shown. DETAILED DESCRIPTION

[0058] exist Figure 1 and Figure 2 A pretreatment machine 1 according to a first embodiment of the invention is shown in FIG. 1 , which is configured as a cleaning machine, i.e. a cotton cleaning machine. More details and possible modifications are given in Figures 3 to 5 In the drawings, in order to illustrate the orientation of the pretreatment machine 1 in space, a longitudinal direction X, a transverse direction Y and a vertical direction Z are drawn, which are defined according to a Cartesian coordinate system associated with the pretreatment machine 1 and are represented by corresponding arrows. The terms "below", "lower", "above" or "upper" here represent a spatial description relative to the vertical direction Z. The pretreatment machine 1 can be placed on a fixed base surface, which is located in a horizontal plane spanned by the longitudinal direction X and the transverse direction Y.

[0059] exist Figure 1 As can be seen in the figure, the pre-treatment machine 1 has a cotton feeding box 2. The cotton feeding box 2 is connected to a feed inlet 4, through which cotton can usually be fed from an upstream pre-treatment machine (e.g. Fig.12 The mixing machine shown in FIG. 1 , here the Truetzschler Universal Mixer MX-U, pneumatically introduces the fiber material 3 provided in the form of wadding. In the upper part 5 of the feed box 2, a dust removal device 6 is arranged, which separates dust and transport air from the fiber material 3. The transport air is discharged through an exhaust pipe 7, while the fiber material 3 falls into the lower part 8 of the feed box 2, where it accumulates during the operation of the pretreatment machine 1. For this purpose, a metering device is arranged in the lower part 8, here in the form of a roller feed section 9, which here has two slowly rotating supply rollers 10, 11 rotating in opposite directions to each other and two slowly rotating feed rollers 12, 13 rotating in opposite directions to each other below the supply rollers 10, 11. The feed rollers 12, 13 form the bottom of the feed box 2, below which an opening roller 14 is arranged.

[0060] The opening roller 14 is provided with a first cleaning element 15 and a second cleaning element in sequence in its rotation direction. This arrangement is described in the applicant's publication DE102012012254A1, which is quoted in its entirety or incorporated herein by reference. The first cleaning element 15 can at least substantially move tangentially along the direction of the double arrow A relative to the tooth tip circumference 17 of the needle clothing 18 of the opening roller 14 in order to adjust the channel of the cleaning position. Through the suction hoods 19 and 20, the waste separated by the cleaning elements 15 and 16 enters the waste branch 21. Along the rotation direction of the opening roller 14, a pipeline system is connected again behind the second cleaning element 16, through which the cleaned fiber material 3 can be transported to a subsequent pre-treatment machine (not shown), such as a foreign matter separator, such as Trützschler's SP-FPU, T-ScanTS-T3 or T-ScanTS-T5. In Figure 1 The arrow T in the figure indicates the transport direction of the cleaned fiber material to the subsequent pre-treatment machine.

[0061] exist Figure 2 As can be seen in the figure, the waste sucked into the waste branch 21 through the suction hoods 19, 20 passes through the waste sensor device 22. The waste sensor device 22 has an optical measuring device, with a sensor 23, 24 for each suction hood 19, 20, in particular a brightness sensor, which looks into the respective suction hood 19, 20 through a transparent partition. The waste transported out through the suction hoods 19, 20 via the waste pipe 25 of the waste branch 21 can be detected by means of the sensors 23, 24, so that good fibers in the waste flow can be identified among the flying fibers. By evaluating the measurement results, the proportion of good fibers in the waste or the waste composition of the waste containing foreign matter and good fibers can be determined.

[0062] Above the roller feed 9, a housing opening 27 is formed in the housing 26 of the pretreatment machine 1 that surrounds the feeding box 2. A light barrier 28 or a photoelectric switch connected to the machine control (not shown) is arranged above the housing opening 27 and serves as a level limiter. As soon as the level F of the fiber material 3 in the feeding box 2 rises to the installation height of the light barrier 28, the replenishment of the fiber material 3 to the pretreatment machine 1 is interrupted until the level F drops again. In this way, the installation height specifies the maximum level Fmax. In addition, a pressure sensor 29 is arranged above the light barrier 28 in the feeding box 2, which can be designed as a differential pressure sensor in order to measure the difference between the spatial pressure existing in the feeding box 2 and the ambient pressure existing outside the feeding box 2. As a result, the influence of the dynamic pressure generated by the transport air flowing into the feeding box 2, which exerts pressure on the fiber material 3 from above and compresses the fiber material, can be determined. Instead of a differential pressure sensor, two separate pressure sensors can also be used.

[0063] The inspection device 30 according to the invention is inserted into the housing opening 27 of the housing 26 of the pretreatment machine 1, and the structure and function of the inspection device will be explained in detail below. Figure 1 and Figure 2 As can be seen in the figure, the inspection device 30 is here exemplarily configured as a pivotable access door or inspection door, which is hinged to the housing 26 by means of a hinge device 61. In addition, a mechanical locking device 62 can be provided so that the inspection device 30 can be locked in its closed state. In principle, the inspection device 30 can also be a fixed window without a hinge device 61 and a locking device 62.

[0064] exist Figure 3As can be seen in the figure, the inspection device 30 has an opening closing device 31, which includes a partition element 32 and a cover element 33. The partition element 32 is designed in a plate-like manner and can end flush with the housing wall 34 of the cotton feeding box 2 surrounding the housing opening 27. During operation of the pretreatment machine 1, the fiber material 3 passes or sweeps along the inner side of the housing wall 34 and the outer side 35 of the partition element 32 facing the cotton feeding box 2 in the direction of the arrow (provided with reference numeral 63). In addition, the opening closing device 31 can have a frame 36 surrounding the partition element 32 and the cover element 33, which serves to fasten the opening closing device 31 to the housing 26. Therefore, the opening closing device 31 can be used like a fixed window, wherein in principle, a pivoting device or a flipping device is also possible in order to configure the opening closing device 31 as a pivotable window or flap. Likewise, the frame 36 can be multi-part and have a frame part that is fixed to the housing 26 and a frame part that can be separated therefrom and comprises a unit consisting of a partition element 32 and a cover element 33, so that the unit can be removed in a simple manner and thus access to the cotton feeding box 2 can be provided for inspection work or maintenance work. An interior space 37 is formed between the partition element 32 and the cover element 33. In order to seal the housing opening 27 and the interior space 37 against dust and moisture, a seal (not shown) can be provided in a manner known per se.

[0065] A camera device 38 is arranged in the interior space 37 of the opening and closing device 31 so as to be able to capture images of the fiber material 3 passing through the defined observation area 39 of the partition element 32 in the cotton feeding box 2 in the direction of the arrow 63. For this purpose, the partition element 32 is designed to be transparent in the observation area 39, wherein, as shown here by way of example, the entire surface of the partition element 32 is designed to be transparent. The outer side 35 of the partition element 32 defines an observation plane E, parallel to which the optical axis 40 of the camera device 38 is oriented. In addition, a deflection device 41 is accommodated in the interior space 37 of the opening and closing device 31, which is arranged in the field of view of the camera device 38 and deflects a light path 42 starting from the observation area 39 toward the camera device 38. Here by way of example, the deflection device 41 includes a mirror with a reflective surface 47. The angle of incidence and the angle of emergence are both 45 degrees, so that the light path 42 is deflected by 90 degrees. Figure 3 It can be seen in FIG. 4 that a first beam path section 43 of the beam path 42 extends perpendicularly to the observation plane E and that the beam path 42 has, after the deflection, a second beam path section 44 which is oriented parallel to the optical axis 40 .

[0066] Here, by way of example, the camera device 38 is arranged in the upper section 45 of the opening closing device 31. Correspondingly, the deflection device 41, which is arranged spaced apart from the camera device 38, is placed in the lower section 46 of the opening closing device 31, in which the observation area 39 is also constructed. In principle, the opposite arrangement is also possible, in which the camera device 38 can be arranged in the lower section 46 and the deflection device 41 and the observation area 39 are arranged in the upper section 45. By adjusting the distance between the camera device 38 and the deflection device 41, the detection width 48 of the camera device 38, i.e. the width of the scanning line, can be specified, which corresponds to the net width 49 of the frame 36 at most if it meets the purpose. Figure 4 and Figure 5 In the embodiment of the present invention, the camera device 38 is arranged at two different distances relative to the deflection device 41. The camera device 38 is fixed in the corresponding position. In the interior space 37, a guide device (not shown) can be provided, which can for example include a guide rail, a rod, a plate with a hole pattern or the like, so that the camera device 38 can be oriented and the inspection width can be adjusted by the distance from the deflection device 41.

[0067] In order to illuminate the fiber material 3 passing through the observation area 39, an illumination device 50 is arranged in the inner space 37 of the opening closing device 31. The illumination device 50 has an upper illumination element 51 and a lower illumination element 52, which illuminate the observation area 39 from obliquely above or obliquely below. Therefore, the observation area 39 is arranged between the two illumination elements 51, 52. Along the optical axis 40, the deflection device 41 is arranged between the camera device 38 and the lower illumination element 52, and the upper illumination element 51 is arranged between the camera device 38 and the deflection device 41. The two illumination elements 51, 52 are configured as strips and extend at least on the detection width 48 of the camera device 38. The illumination elements 51, 52 may include a plurality of LED light sources 53 with lenses. In order to avoid light reflection, the incident angle deviates from the surface normal of the observation plane E and intersects the observation plane E in the range between 20 degrees and 80 degrees as an example here. In order to shield the viewing area 39 from ambient or extraneous light, the cover element 33 can be designed to be light-proof in the lower section 46 .

[0068] The camera device 38 has a camera 54 with a lens 55, here for example a line array camera, wherein in principle an area array camera can also be provided. The camera 54 is connected to an electronic evaluation unit 57 via a data line 56, which analyzes the image data received by the camera device 38. The evaluation unit 57 is configured to evaluate the number, frequency and / or total area of ​​foreign bodies in the fiber material by means of image processing methods in order to be able to output the foreign body content in the fiber material 3. The evaluation unit 57 can, for example, identify foreign bodies based on brightness differences and / or color differences. Here, by way of example, the evaluation unit 57 is arranged in the upper section 45 in the interior space 37. In this way, the fiber material can be optically inspected from the machine side equipped with the inspection device 30 in order to identify foreign bodies in the fiber material 3.

[0069] The embodiment of the pretreatment machine 1 shown here has only a single inspection device 30. The housing wall 58 opposite the inspection device 30 is designed to be closed here, but can have an inspection opening or the like in a manner known per se, in which the inspection device 30 can basically also be inserted.

[0070] The inspection device 30 can have an interface so that the inspection device 30 can be connected to a power supply system and / or a bus system, in particular a field bus, after being inserted into the housing opening 27. The interface can include, for example, plug contacts, connection points, etc., which are connected to at least one mating element arranged on the machine side. In this way, the electronic components of the inspection device 30, such as the camera device 38, the lighting device 50 and the evaluation unit 57, can be supplied with power and / or coupled to a control unit, in order to transmit output values ​​of the evaluation unit 57 to the control unit, for example. The control unit can be assigned to the pretreatment machine or a higher-level device control unit that communicates with the control units of a plurality of other pretreatment machines.

[0071] During operation of the pretreatment machine 1, the fibrous material 2 is pneumatically transported through the feed opening 3 into the feed box 2. The transport air is discharged through the dust removal device 6 and the fibrous material 3 is collected in the lower part 8 of the feed box 2. Due to the slow operation of the roller feed part 9, the fibrous material accumulates in the feed box 2, wherein the material level F is usually located above the observation area 39 and below the light barrier 28. In the case of high production rates, it may happen that the material level F is below the observation area 39 for a short time. In order to avoid the image being taken at this time, a material level sensor can be provided, such as another light barrier, a photoelectric switch, etc.

[0072] exist Figure 66 shows a possible flow chart of the automatic operation of the pretreatment machine 1. With the start 65, the cleaning elements 15, 16 have been optimized and adjusted for the specified initial value by means of the initial optimization operation. The specified initial value can correspond to the foreign matter content manually input by the operator based on the quality of the purchased or investigated raw materials. The optimization operation can be performed in the continuous operation of the pretreatment machine 1, wherein the roller feed section 9 and the opening roller 14 continue to be driven rotationally. During the optimization operation, the optical sensors 23, 24 of the waste sensor device 22 check the waste composition of the waste sucked out by the suction hood 19, 20. At the beginning of each optimization operation, the first cleaning element 15 can first move to the first position, where the cleaning point or cleaning port is closed. In the first position, the separation rate of foreign matter is initially low. Then, the first cleaning element 15 can move along the double arrow A and gradually release the cleaning port, wherein the content of foreign matter increases. From a certain point, the ratio of the content of good fiber to the content of foreign matter always increases further. Then, the first cleaning element 15 moves to the position where the ratio between foreign matter and good fiber in this optimization operation is most favorable. The ratio of foreign matter to good fibers resulting from the optimization run is stored as a waste value. Thus, according to the specified parameters stored in the control unit or given by the operator of the pretreatment machine 1, the machine components that influence the waste composition (here the cleaning elements 15, 16) can be automatically adjusted for a long time until the desired waste quality is achieved. The optimization run performed based on the initial values ​​thus optimizes the cleaning efficiency of the pretreatment machine 1.

[0073] After the automatic operation starts 65, the current or actual foreign matter content in the fiber material 3 is detected or monitored in step 70. Step 70 includes a plurality of sub-steps, which are Figure 7 . After the foreign body detection starts 71, the camera device 38 records an image of the fiber material 3 passing behind the observation area 39 in a substep 72, wherein the illumination device 50 illuminates the observation area 39 during the recording by the reflected light method. Subsequently, the evaluation unit 57 evaluates the image data transmitted by the camera device 38 about the detected image in a substep 73. Here, the received image data are evaluated with the help of image processing methods in terms of the number, frequency and / or total area of ​​foreign bodies in the fiber material 3. Usually, foreign bodies such as stems, leaves or general "garbage" particles appear as areas that are darker than the cream- to white-colored fiber material 3. Since almost binary states already exist, the found foreign bodies can be subdivided in front of the bright background of the fiber material 3, for example by thresholding operations. The scene can then be conventionally decomposed to extract objects with characteristics such as size, area, contour, etc. The foreign body content can be determined by counting dark objects or by accumulating areas. In addition, size histograms can be generated or objects can be classified into groups such as garbage, stems, leaves, etc.

[0074] In a substep 74, a query is made as to whether the image area detected by the camera device 38 corresponds to a defined minimum area. In order to generate output values ​​or measured values ​​from the image data, which represent the foreign matter content in the fiber material reliably or statistically with certainty, it has proven to be advantageous when the minimum area detected by the camera device 38 reaches a defined minimum value. A very high accuracy is achieved when the minimum area is greater than 2 square meters and further preferably at least approximately 3 square meters. Since the detection area of ​​the line scan camera 54 is smaller than the minimum area, for example only 90 square millimeters, further images are recorded 72 and evaluated 73 for a longer period of time until the defined minimum area is reached.

[0075] In order to be able to react as quickly as possible to the foreign matter content of the fiber material 3 by adjusting the cleaning elements 15, 16, a goal is to detect the defined minimum area of ​​the fiber material 3 in the shortest possible time, without repeatedly detecting foreign matter. Because the pre-treatment machine 1 shown here has only a unique inspection device 30, the required minimum area must be detected by the image of one of the camera devices 38. For example, the detection area of ​​the camera device can be increased by increasing the distance between the camera device 38 and the deflection device 41 or the observation area 39, so that a larger area can be detected by an image. The image capture frequency depends on the transport speed and can only be increased within a limited range to avoid multiple counting of the same foreign matter. For example, when the transport speed is 120 to 360 millimeters per minute, it can be captured with an image capture frequency of 13 to 80 Hz. For example, when the detection area or image area of ​​an image of the camera device 38 is only 90 square millimeters, the measurement time to reach the minimum area of ​​3 square meters here, for example, is 14 minutes. Therefore, the higher transport speed that can be achieved by higher productivity allows a higher image capture frequency, so that the minimum area can be detected faster. Therefore, when evaluating the images, the evaluation unit 57 takes into account the images formed in a line scan manner as is customary for line scan cameras and evaluates these images with respect to foreign matter using image processing algorithms. The evaluation results of the individual images are accumulated in order to improve the accuracy of the determination of the foreign matter content in the fiber material 3 .

[0076] In substep 75, the evaluation unit 57 takes into account the dynamic pressure in the feeding box 2 measured by the pressure sensor 29 when evaluating the image. The transport air flowing into the feeding box 2 always leads to a certain degree of compression of the fiber material 3 in the feeding box 2, which can influence the accuracy of the output value. In order to minimize this influence and eliminate it as much as possible, the pressure sensor 29 is coupled to the evaluation unit 57. With the help of the measured dynamic pressure and the calibration curve stored in the evaluation unit 57, the output value of the evaluation unit 57 can be corrected to a characteristic variable that is independent of the dynamic pressure. The evaluation unit 57 outputs its corrected output value to the control unit of the pretreatment machine 1. The corrected output value is transmitted to the control unit, see substep 76. The foreign matter content detection ends with 77. The process for foreign matter detection according to substeps 71 to 77 can be repeated regularly. A plurality of the detection processes described can also be carried out simultaneously in a time-staggered manner, so that the current foreign matter content can be provided in a shorter time interval with the help of the updated output value.

[0077] According to Figure 6 , step 70 is followed by step 80, in which the waste composition is determined with the aid of the waste sensor device 22. The waste sensor device 22 can monitor the waste composition periodically and, in principle, also continuously, so that step 80 can also be performed simultaneously with step 70. The waste sensor device 22 determines the composition or the good fiber content of the waste sucked out by the suction hoods 19, 20 with the aid of the optical sensors 23, 24.

[0078] Based on the corrected output values ​​and waste composition, in particular, it can be decided in step 85 whether the cleaning of the pretreatment machine 1 needs to be optimized ("yes"). If none of the criteria mentioned below are met, the cleaning elements 15, 16 are currently optimally adjusted and currently do not need to be optimized ("no"), so that the method continues in a loop containing steps 70, 80 and 85.

[0079] When any of the following criteria are met, optimization is performed in step 90:

[0080] if, in particular, the corrected output value remains unchanged compared to an initial value set or specified in a previous or initial optimization run, or at least lies within a specifiable tolerance range around the initial value, whereas the waste composition or the waste amount deviates from the waste value set in a previous optimization run and in particular lies outside a specifiable tolerance range around the waste value;

[0081] if the waste composition or the waste amount remains unchanged or at least lies within a predefinable tolerance range around the waste value compared to the waste value set in a previous or initial optimization run, but a change in the output value after correction is observed over time, in particular because the output value lies outside the predefinable tolerance range, a sudden increase in the output value is detected or a continuous increase or decrease is recognized in the observation of the integration over time;

[0082] If, in particular, not only the corrected output value lies outside a predeterminable tolerance range around the initial value, but also the waste composition or the waste amount lies outside a predeterminable tolerance range around the waste value.

[0083] Optimization 90 includes multiple sub-steps, which are Figure 8 . After the start 91, an optimization run 92 is performed, wherein in step 92 the positions of the cleaning elements 15, 16 are changed and the changing waste composition is monitored simultaneously by means of the waste sensor device 22. Here, according to the specified parameters stored in the control unit or given by the operator of the pretreatment machine 1, the machine components (here the cleaning elements 15, 16) that influence the waste composition are automatically adjusted for a long time until the desired waste quality is reached for the detected output value, which reflects the current waste content. Instead of a complete optimization run 92 (in which the first position is first driven), it is also possible to start from the currently adjusted operating point and check by slightly adjusting the cleaning elements 15, 16 whether an improvement in the separation efficiency is achieved by a small adjustment. In substep 93, the current output value is detected, which represents the current foreign matter content in the fiber material 3. In substep 94, the current waste composition is detected, which represents the ratio between foreign matter and good fibers. In substep 95, the current output value is set as the initial value and the current scrap composition is set as the scrap value and is thus used as a reference value for the subsequent decision according to step 85. The optimization 90 ends with 96. Preferably, the optimization 90 is carried out fully automatically and is started and monitored by the control unit. In principle, a confirmation by the machine operator may be required before each optimization run. Each optimization run can be displayed visually and / or recorded digitally.

[0084] In order to always be able to provide output values ​​that are as up-to-date as possible, the process 70 for detecting foreign matter with the substeps 71 to 77 can be repeated regularly as a background process. Likewise, in particular, the waste composition 80 can be continuously detected.

[0085] The inspection device 30 can preferably also be used as a viewing port through which the operator of the pretreatment machine 1 can look into the interior of the cotton feeding box 2. For this purpose, the opening closing device 31 can have a viewing section 59, in which the cover element 33 and the partition element 32 are both designed to be transparent and the components built in the interior space 37 do not hinder the fiber material 3 from being seen from the outside. Preferably, the viewing section 59 is a middle section of the opening closing device 31, which is arranged between the upper section 45 and the lower section 46. When the operator himself recognizes a change in the foreign matter content by looking into the cotton feeding box 2 from the outside through the viewing section 59, the optimization 90 can also be manually triggered, for example, by an application on a mobile terminal device, an operating terminal of the pretreatment machine 1 and / or a higher-level control unit.

[0086] exist Fig. 9 An alternative embodiment of a pretreatment machine 1 is shown in , which largely corresponds to the preceding embodiments, so that reference is made to the above description with regard to common points. The difference is that the pretreatment machine 1 has a plurality (here, for example, two) of inspection devices 30. The two inspection devices 30 are installed in housing openings 27 in two housing walls 34, 58 arranged opposite each other. By recording images of the fiber material surface of the fiber material 3 from a plurality of observation areas 39, changes in the raw material quality can be detected more accurately and more quickly, since a plurality (here, two) of camera devices 38 simultaneously contribute to achieving the minimum area (substep 74). The process therefore largely corresponds to that in Figures 6 to 8 . Each camera device 38 is assigned an evaluation unit 57, which analyzes the image data of the associated camera device 38. The evaluation unit 57 transmits its results via a drawn data line to a further or higher-level evaluation unit 60, in which the individual results are combined. In this way, the required measuring time is shortened, and in the case of using two camera devices 38, the required measuring time is halved.

[0087] exist Fig.10A further embodiment of an inspection device 30 is shown in the figure, which corresponds largely to the aforementioned inspection device 30, so that reference is made to the above description with regard to common points. The only difference is that the camera device 38 of the corresponding inspection device 30 here has two cameras 54', 54" (for example line array cameras) instead of one camera 54, each camera having a lens 55', 55". Their optical paths 44', 44" are oriented parallel to the respective optical axes 40', 40". Instead of a line array camera, a matrix camera or an area array camera can also be used. In this way, the detection width 48 of the camera device 38 can be increased, thereby shortening the measurement time to reach the minimum area. Furthermore, due to the larger detection width 48, the distance of the cameras 54', 54" from the deflection device 41 can also be reduced. These aspects are particularly advantageous in the case of a wider observation area 39 and / or a lower housing opening 27, which only provides a small structural height in the extension along the vertical axis Z direction. In addition, the line of sight of the lenses 55', 55" to the edges of the individual camera images remains sufficiently steep so that optical errors such as distortion, edge light attenuation, loss of sharpness, etc. are negligible. The lighting device 50 covers the entire detection width 48, which here, by way of example, corresponds to the clear width 49 of the frame 36.

[0088] exist Fig.11 , another embodiment of the pretreatment machine 1 is shown, which corresponds to the above embodiment to a large extent, so that reference is made to the above description for common points. The difference lies in the design of the deflection device 41 and the lighting device 50. The first optical path section 43 is directed obliquely upward, which is, for example, at an angle of 45 degrees to the observation plane E. The optical path 42 is deflected by the deflection device 41, so that the second optical path section 44 extends parallel to the optical axis 40 of the camera device 38. The lighting device 50 has only a lower lighting element 52, which is directed perpendicularly to the observation plane E to the observation area 39 in order to exclude disturbing light reflections on the transparent partition element 32, which may appear in the image of the camera device 38 or in the image data. Therefore, the angle of incidence and the angle of emission on the mirror surface of the deflection device 41 are both greater than 45 degrees and can be 67.5 degrees as shown here by way of example. As a result, the deflection device 41 and the camera device 38 can be arranged closer to the partition element 32, so that the opening closing device 31 can be designed to be flatter in structure.

[0089] In Fig.10, the camera device 38 can in principle also be arranged higher up in the interior space 37 using the embodiment shown in FIG. 4 as an example. Here, the camera device 38 is arranged between the partition element 32 and the evaluation unit 57. Due to this nested arrangement, the distance between the camera device 38 and the deflection device 41 is increased, thereby increasing the detection width 48. It goes without saying that all the individual features shown in the embodiments can be used interchangeably and vice versa. For this purpose, it is only emphasized by way of example that the camera device 38 is arranged higher up in the interior space 37. Figures 1 to 8 In the embodiment shown, it is also possible to position the evaluation unit 57 in a nested arrangement in order to move the camera device 38 upward as far as possible; or the opening closing device 31 is designed as a rigid window or a pivotable window; etc.

[0090] exist Fig.12 1 shows a pretreatment machine 100 according to another embodiment, which is designed as a blending machine and has a plurality of inspection devices 30. The inspection device 30 can be as shown in Figures 1 to 5 and Figures 9 to 11 , so that reference is made to the above description with regard to common points. Here, identical or modified details are provided with the same reference numerals. Fig.12 In order to illustrate the orientation of the pretreatment machine 100 in space, a longitudinal direction X, a transverse direction Y and a vertical direction Z are drawn, which are defined according to a Cartesian coordinate system associated with the pretreatment machine 100 and are represented by corresponding arrows. The terms "below", "lower", "above" or "upper" here represent spatial descriptions relative to the vertical direction Z. The pretreatment machine 100 can be placed on a fixed base surface, which is located in a horizontal plane spanned by the longitudinal direction X and the transverse direction Y.

[0091] The preparation machine 100 has a plurality of (here, for example, ten) feeding boxes 2 arranged one after the other in a row. The feeding boxes 2 are connected to a channel 101 extending above the feeding boxes 2 and connected on the inlet side via a feed opening 4 to an upstream textile preparation machine (not shown). The fibrous material 3, which is usually provided in the form of wadding, is pneumatically introduced into the feeding boxes 2 via the feed opening 4 and the channel 101. A control mechanism (not shown) can be provided between the channel 101 and the individual feeding boxes 2 in a manner known per se, in order to be able to control the filling of the individual feeding boxes 2. In a manner known per se, a roller feed section and opening rollers are arranged in the lower part 8 of the respective feeding box 2, such as in the feed opening 4. Figure 1 and Figure 2 In addition, a common mixing channel can be arranged below the cotton feeding box 2, and the fiber material accumulated therein is transported from the mixing channel through a pipeline system along the transport direction T to a subsequent pre-treatment machine, for example, in Figure 1 and Figure 2 The cotton cleaning machine 1 is shown in FIG.

[0092] For each cotton feeding box 2, an inspection device 30 is installed in a housing opening in the front housing wall 34 of the pre-treatment machine 100. However, it is also possible that the pre-treatment machine 100 has only one of these inspection devices 30 in total, or that only a part of the cotton feeding boxes 2 is monitored with one of the inspection devices 30. The images detected during operation are evaluated with the aid of the evaluation unit 57 and, if necessary, with the aid of at least one superior evaluation unit 60. The output values ​​can be combined and averaged to obtain more representative results. Parallel inspection with multiple inspection devices 30 can provide statistically more accurate data about the quality of the raw material, in particular the foreign matter content, in a shorter measuring time. In addition, other inspection devices 30 can also be arranged on the rear wall of the pre-treatment machine 100, such as Fig.12 The more inspection devices 30 are provided, the shorter the achievable measuring time is. For example, two inspection devices 30 can be provided for each feeding box 2, one on the front side and the other on the rear side, so that the blending machine 100 shown here by way of example with ten feeding boxes 2 can have, for example, twenty inspection devices 30.

[0093] By summarizing the individual results (here twenty), the evaluation time can be significantly reduced. The central control unit or one of the evaluation units, in particular the superior evaluation unit 60, can be responsible for summarizing the output values ​​and transmitting them to the control unit. The control unit can be assigned to a downstream textile preparation machine, in particular a cleaning machine 1, which can automatically change the adjustment of machine elements that influence the waste separation based on the foreign matter content detected in the blending machine 100, for example changing the position of the cleaning elements 15, 16.

[0094] Reference numerals:

[0095] 1Pre-treatment machine 41Deflection device

[0096] 2 cotton feeding box 42 light paths

[0097] 3 fiber material 43 optical path section

[0098] 4 feeding ports 44 optical path sections

[0099] 5 Upper Section 45 Upper Section

[0100] 6 Dust removal device 46 lower section

[0101] 7 Exhaust pipe 47 surface

[0102] 8 Lower part 48 detection width

[0103] 9 Roller feed section 49 net width

[0104] 10 supply roller 50 lighting device

[0105] 11 supply roller 51 lighting element

[0106] 12 Feed Rollers 52 Lighting Elements

[0107] 13 feed roller 53 light source

[0108] 14 opening rollers 54 cameras

[0109] 15 cleaning elements 55 lenses

[0110] 16 cleaning element 56 data line

[0111] 17 tooth tip circumference 57 evaluation units

[0112] 18 card clothing 58 shell wall

[0113] 19 suction hood 59 visible section

[0114] 20 Extraction Hood 60 Evaluation Unit

[0115] 21 Waste branch 61 Hinge device

[0116] 22 waste sensor device 62 locking device

[0117] 23 sensors 63 directions

[0118] 24 sensor 65 start

[0119] 25 Waste Tube 70 Steps

[0120] 26 Shell 71-76 Substeps

[0121] 27 Shell opening 77 End

[0122] 28 grating 80, 85, 90 steps

[0123] 29 Pressure sensor 91 Start

[0124] 30 Inspection device 92 Optimized operation

[0125] 31 Opening and Closing Device 93-95 Sub-steps

[0126] 32 separation element 96 end

[0127] 33 Cover element 100 pre-treatment machine

[0128] 34 Shell wall 101 channel

[0129] 35 Outer side

[0130] 36 Frame A Direction

[0131] 37Interior Space E Observation Plane

[0132] 38 camera device F material level

[0133] 39 Observation area T transport direction

[0134] 40Optical axis X, Y, ZLongitudinal, transverse, vertical directions

Claims

1. An inspection device (30) for detecting foreign bodies in a fiber material, the fiber material being contained in a pre-treatment machine (1; 100), in particular in a feeding box (2) of a textile preparation machine, wherein: The inspection device (30) comprises: - an opening closing device (31) for closing a housing opening (27) of the pretreatment machine (1; 100), through which the cotton feeding box (2) can be seen from the outside, wherein the opening closing device (31) has a partition element (32) and a cover element (33) arranged on the partition element (32), the partition element (32) having a transparent viewing area (39) defining a viewing plane (E), wherein an inner space (37) is formed between the partition element (32) and the cover element (33); and - a camera device (38) arranged in the interior space (37), It is characterized in that - the optical axis (40) of the camera device (38) is oriented at least substantially parallel to the observation plane (E), and A deflection device (41) is arranged in the interior space (37) of the opening closing device (31), which deflects a light path (42) originating from the observation area (39) toward the camera device (38).

2. The inspection device (30) according to claim 1, characterized in that The deflection device (41) has a reflective surface (47), wherein the angle of incidence between the optical path (42) and the surface normal of the reflective surface (47) is 45 degrees, or wherein the angle of incidence between the optical path (42) and the surface normal of the reflective surface (47) is greater than 45 degrees and less than 85 degrees.

3. The inspection device (30) according to claim 1 or 2, characterized in that: The camera device (38) includes at least one line array camera (54; 54', 54").

4. The inspection device (30) according to any one of claims 1 to 3, characterized in that A lighting device (50) is arranged in the interior space (37) for illuminating the fiber material (3) passing through the observation area (39), wherein the lighting device (50) extends over the entire width of the observation area (39).

5. The inspection device (30) according to any one of claims 1 to 4, characterized in that The opening closing device (31) has an upper section (45) and a lower section (46) which is axially spaced apart from the upper section (35) with respect to the optical axis (40), wherein the camera device (38) is arranged in the upper section (45) and the observation area (39) and the deflection device (41) are arranged in the lower section (46).

6. The inspection device (30) according to any one of claims 1 to 5, characterized in that The cover element (33) is designed to be light-proof in the lower section (46).

7. The inspection device (30) according to any one of claims 1 to 6, characterized in that The opening closing device (31) has a visible section (59) in which the partition element (32) and the cover element (33) are designed to be transparent, in particular wherein the visible section (59) is arranged between the upper section (45) and the lower section (46).

8. The inspection device (30) according to any one of claims 1 to 7, characterized in that The opening closing device (31) has hinge means (61) for being pivotably fastened to the pretreatment machine (1; 100) in the region of the housing opening (27).

9. Use of the inspection device (30) according to one of claims 1 to 8 for closing a housing opening (27) already present in a pretreatment machine (1; 100), through which a feed box (2) for the fiber material (3) is visible from the outside.

10. A pretreatment machine (1; 100), comprising a housing (26), which surrounds at least one feeding box (2) for fiber material (3) and has at least one housing opening (27), through which the feeding box (2) is visible from the outside; and the pretreatment machine has at least one inspection device (30), which is constructed according to one of claims 1 to 8 and is inserted into at least one of the at least one housing opening (27).

11. The pretreatment machine (1; 100) according to claim 10, characterized in that A pressure sensor (29) for measuring dynamic pressure is arranged in the at least one cotton feeding box (2), wherein the pressure sensor (29) is arranged above a specified maximum filling level (Fmax) of the at least one cotton feeding box (2), and the at least one inspection device (30) is arranged below the maximum filling level (Fmax).

12. The pretreatment machine (1; 100) according to claim 11, characterized in that A light barrier (28) or a photoelectric switch is arranged in the at least one cotton feeding box (2), wherein the installation height of the light barrier (28) or the photoelectric switch specifies the maximum material level (Fmax).

13. An apparatus comprising a plurality of pre-treatment machines (1; 100) according to one of claims 10 to 12.

14. Method for detecting foreign bodies in fiber material (3) contained in a feeding box (2) of a pretreatment machine (1; 100) according to one of claims 10 to 12 or in a feeding box (2) of an apparatus according to claim 13, wherein: The method comprises the following steps: - recording (72) an image of the fiber material (3) passing through the observation area (39) by means of a camera device (38) of a corresponding inspection device (30); - evaluating (73) the recorded image by at least one evaluation unit (57) to determine the foreign matter content in the fiber material (3); - outputting (76) at least one output value, said output value comprising the foreign matter content in the fibrous material (3).

15. The method according to claim 14, characterized in that At least one of the pre-treatment machines (1; 100) or the apparatus has at least one waste sensor device (22) which is configured to determine the waste composition of waste separated from the fiber material (3) containing foreign matter and good fibers by means of at least one optical sensor (23, 24), and the method comprises at least one of the following steps: - comparing (85) the at least one output value with at least one specified and / or previous initial value; - in a corresponding pre-treatment machine (1; 100) and / or in a corresponding pre-treatment machine (1; An optimization operation (92) is performed on a textile preparation machine (1; 100) downstream of a textile preparation machine (1; 100) and / or a textile preparation machine (1; 100) upstream of a corresponding pretreatment machine (1; 100), in which the position or rotation speed of at least one cleaning element (15, 16) for separating waste from fiber material (3) is automatically changed when at least one output value deviates from at least one initial value, wherein the current waste composition (80) of the separated waste containing foreign matter and good fibers in the waste branch (21) downstream of the at least one cleaning element (15, 16) is determined by means of a waste sensor device (22) and at least one optical sensor (23, 24).

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