Inspection device, application, pre-treatment machine, apparatus and method for identifying foreign bodies in fibrous material

Abstract

The invention relates to an inspection device (30) for identifying foreign bodies in a fibrous material, which is accommodated in a feed box (2) of a pre-treatment machine (1; 100), in particular a textile preparation machine, wherein the inspection device (30) comprises an opening closure device (31) for closing a housing opening (27) of the pre-treatment machine (100), through which the feed box (2) can be seen from the outside, wherein the opening closure device (31) has a partition element (32) with a transparent viewing area (39) defining a viewing plane (E) and a cover element (33) arranged on the partition element (32), 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 inner space (37), characterized in that an optical axis (40) of the camera device (38) is oriented at least substantially parallel to the viewing plane (E), and a deflection device (41) is arranged in the inner space (37) of the opening closure device (31), which deflects a light path (42) proceeding from the viewing area (39) towards the camera device (38). The invention also relates to the use of the inspection device, a pre-treatment machine, a plant having a plurality of pre-treatment machines and a method for optically inspecting a fibrous material.

Description

Technical Field

[0001] This invention relates to an inspection device for identifying foreign objects in fibrous materials housed in a feed box of a pretreatment machine, particularly a textile preparation machine. The inspection device includes an opening-closing device for closing an opening in the housing of the pretreatment machine through which the feed box can be viewed from the outside. The opening-closing device includes a separating element and a cover element disposed on the separating element, the separating element having a transparent viewing area defining a viewing plane, wherein an internal space is formed between the separating element and the cover element. A camera device is arranged in the internal space. The invention also relates to applications of the inspection device, pretreatment machines, apparatus having multiple pretreatment machines, and methods for identifying foreign objects in fibrous materials. Background Technology

[0002] In spinning mills, the fiber quality of purchased fiber bales (e.g., made from cotton, polyester, blended fibers, etc.) is known. However, inferring yarn quality from the quality of fiber samples in the cleaning process is quite difficult. Quality fluctuations in fiber bale samples often go undetected during continuous processing, making it impossible to adapt the necessary machine adjustments to consistently achieve optimal yarn quality despite these fluctuations. Among the many possible raw material parameters for fiber materials, the detection of foreign matter or interfering particle content is a common one. Foreign matter present in compressed fiber bales includes plant components such as stems, leaves, and seeds (often referred to as "garbage"), or packaging residues such as fabric, textiles, films, and plastic bags. Of these foreign matter, only plant-based foreign matter (garbage) is detected among the classified raw material parameters in purchased fiber bales. Other components, due to their relatively low frequency, are almost impossible to detect using traditional sampling methods employing laboratory analytical instruments. Furthermore, their actual content fluctuates greatly. However, even regarding the content of plant components, the actual raw material quality differs significantly from the classification value. Considering the quality requirements of the final product, as well as energy use and resource-efficient disposal of raw materials, this actual raw material quality necessitates adjustments to the pretreatment machine. However, in practice, readjusting the machine based on fluctuations in raw material quality is impractical because the experimentally analyzed measurement methods available are too slow to generate the necessary adjustment parameters early enough, i.e., while the material is still being processed, or are associated with significant waste.

[0003] A sensor is known from DE102019115138 that can also automatically determine the foreign matter content in the carding machine fiber web during operation. This sensor provides quality data after the final critical processing step of carding. The foreign matter content determined there is well-suited for describing the quality of yarn produced subsequently; however, it does not detect the current quality of the supplied raw materials, nor the quality of the fiber material at previous intermediate steps such as pre-cleaning, mixing, cleaning, opening, and foreign matter separation. If a quality problem occurs here, it is unclear whether it is caused at the raw material stage or at one of the previous process steps.

[0004] EP3951033A1 describes a sampling method at cleaning points of various textile preparation machines. Waste accumulated at the cleaning points is sucked away through a network of pipes and locking mechanisms and transported via conveyor pipes to a central container equipped with a weighing device. A camera is aimed at this weighing device. The weighing device, camera, fan, and locking mechanisms are connected to a control unit. The control unit initiates the transfer of waste from the cleaning points. To do this, the corresponding locking mechanism at the connection point of the respective cleaning point (e.g., at the coarse filter) is opened, and the fan is turned on. Waste from the coarse filter is sucked into the central container via the conveyor pipe, released by the transport gas, and fills 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 are emptied sequentially, and the waste sucked away is conveyed to the central container. The waste composition should be analyzed using the camera to adapt or optimize the adjustments of the corresponding spinning preparation machines.

[0005] The disadvantages are that periodic sampling can only achieve a small number of sample parameters for each textile preparation machine and does not allow for continuous monitoring. Furthermore, the waste composition cannot be used to infer the quality of the incoming raw materials. In addition, the project and assembly costs of multiple pipes, locking mechanisms, and the necessary control devices are also considered disadvantages, and these obviously need to be repeated for each spinning unit with its own individual machine sequence.

[0006] EP3951032A1 describes a device with a camera for identifying interfering particles in a fibrous material collected in the feed box of a textile preparation machine. The camera is arranged at a maximum angle of + / -30 degrees relative to a vertical line aligned with the fiber surface. This arrangement, where the camera's line of sight is at least substantially perpendicular to the fiber material, describes an arrangement that is advantageous for sensing and evaluation and easy to implement; however, it results in accessibility issues for the textile preparation machine. Summary of the Invention

[0007] The objective of this invention is to provide an inspection device, its application in a pretreatment machine, a pretreatment machine having such an inspection device, an apparatus having a plurality of said pretreatment machines, and a method by means of which the identification of foreign matter in fibrous materials can be further optimized.

[0008] This task is solved by the aforementioned type of inspection device in such a way 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 internal space of the opening-closing device, which deflects the light path originating from the observation area toward the camera device.

[0009] The advantage lies in the flat structure of the inspection device. Therefore, the inspection device can be easily inserted into the housing opening without protruding obstructively. Because the camera device is not directly aimed at the observation area, but rather the light path is deflected or folded by the deflection device, the camera devices can be arranged at small intervals relative to the observation plane. Therefore, the extension perpendicular to the observation plane, i.e., the depth of the inspection device, can be designed to be as small as possible. Furthermore, since the light path is deflected by the deflection device, the path between the camera device and the observation area is lengthened, thereby expanding the inspection area without increasing the structural depth. With the help of the camera device, optical inspection of the fiber material passing through the inspection device can be performed from the outside (i.e., outside the cotton feeding box) through the transparent observation area to determine quality characteristics, especially foreign matter content, and thus to identify quality fluctuations more quickly. Therefore, sampling from the fiber material is eliminated.

[0010] Here, "at least substantially parallel" should mean that the optical axis can be oriented parallel to the observation plane in a preferred manner, which should also include a predetermined deviation from parallelism within a range of +15 degrees to -15 degrees. When a parallelism deviation exists, the intersection of the optical axis and the observation plane may be located outside the observation area, so the camera device is not directly aimed at the observation area, but always observes the observation area through a deflection device.

[0011] The camera assembly and deflection device are preferably housed entirely within the interior space of the opening-closing device. A cover element is arranged on the partition element and thus protectively covers the camera assembly disposed between the partition element and the cover element. Preferably, the cover element and the partition element are fixedly connected to each other. The partition element can be designed as a planar surface, wherein its design preferably corresponds to the shape and profile of the housing wall surrounding the housing opening to ensure the smooth passage of fibrous material. The partition element can also be referred to as a partition wall. The cover element can be designed, for example, in a basin or bowl shape to form an interior space.

[0012] The deflection device may have a reflective surface. The angle of incidence or exit between the light 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 exit can be greater than 45 degrees, more preferably greater than 50 degrees, and particularly less than 85 degrees. This allows the camera device to be placed closer to the separating element, thereby providing a flatter inspection device. Depending on the orientation, the angle of incidence or exit can also be less than 45 degrees, and particularly greater than 15 degrees. While this achieves a slightly greater structural depth, it also results in a greater distance between the camera device and the observation area, thereby increasing the detection area of ​​the camera device. The deflection device may include at least one deflection element, particularly a mirror, wherein, alternatively to the mirror or as another deflection element, a light conductor or the like may be provided.

[0013] An illumination device can be arranged within the internal space of the opening-closing device to illuminate the fibrous material passing through the observation area. This improves image quality. The illumination device can extend across the entire width of the observation area. In particular, the illumination device can include multiple light-emitting diodes (LEDs) or LED light sources, which can have lenses to ensure uniform distribution of light emitted from each LED. Furthermore, the illumination device can have a lower illumination element, wherein, when viewed along the optical axis, a deflection device is arranged between the camera device and the lower illumination element. Attached to or 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, both the upper and / or lower illumination elements can be designed in the form of light strips or LED strips.

[0014] To avoid light reflection in images captured by a camera device, at least one illumination element aligned with the observation area can be arranged at an angle of incidence significantly deviating from the surface normal of the observation plane. This is particularly suitable when two illumination elements are arranged both above and below the observation area. It is also possible that the angle of incidence of the illumination element can be perpendicular to the observation plane. This is especially advantageous when the optical path between the observation area and the deflection device is inclined relative to the surface normal.

[0015] With the aid of an illumination device, the observation area is illuminated at least during image capture. In an extended version, the observation area is permanently illuminated with the aid of the illumination device. Furthermore, this is advantageous when the camera device includes a line scan camera. Similarly, a flash pattern using an illumination device to generate a flash may also be advantageous in situations where different wavelengths of light should be used alternately to identify different types of foreign objects, or where the movement of fibrous material along the observation area is so slow that no light is needed between image captures.

[0016] In particular, the camera device has at least one camera. A deflection device redirects the light path from the observation area to at least one camera. Furthermore, the number of cameras used depends on the width of the observation area, the maximum detection width of each camera, the size of the internal space, the distance between the camera device and the observation area, etc. Preferably, the camera device includes exactly one or two cameras. To increase the detection width of each camera, the cameras can be placed as high as possible within the internal space. Additionally, the focal length of the lens can be reduced. However, this may result in a large viewing angle towards the edge of the detection area, which could be associated with optical disadvantages. When using multiple cameras, these cameras can be arranged side-by-side along the width direction of the separating element and, in particular, spaced apart from each other. Here, the detection areas of adjacent cameras can also overlap to ensure gapless coverage of the observation area.

[0017] Furthermore, the camera device may include an evaluation unit, also known as an image evaluation computer, for analyzing image data associated with the camera device. The evaluation unit is preferably located within an internal space. However, in principle, it is also possible for the evaluation unit to be located outside the internal space and, for example, on or within the pre-processing machine. The evaluation unit analyzes the image data received by the camera device and provides its evaluation results in the form of at least one output value, which can be used, for example, by the control unit of the pre-processing machine and / or by textile preparation machines upstream or downstream of the pre-processing machine, to adjust machine components affecting the cleaning level of the respective machines. In this way, cleaning efficiency can be optimized by recognizing the varying foreign matter content in the fiber material.

[0018] The at least one camera can be a line scan camera. This enables detection with a large detection width or a large viewing angle along the line scan, which can be oriented along the width of the observation area or the width of the housing opening. The line scan camera captures images line by line. The individual image lines can be combined into a continuous image by the evaluation unit. The fiber material moves through the observation area and the camera device is fixedly held on the opening closure device, i.e., the camera remains stationary. The detection area, i.e., the image field at the time of capture, is a slit of the desired image width, which preferably corresponds at most to the width of the separating element. Thus, the line scan camera requires only a very small structural depth, so that on the one hand, the deflection device can be arranged close to the separating element and the opening closure device can be designed to be structurally flat. In addition, the observation area can be narrow in height and correspondingly wide in width. To avoid optical disadvantages caused by large viewing angles at the edges, it is advantageous that the viewing angle from the camera center to the image edge is at most 15 degrees. In typical opening closure devices for cotton cleaning machines, cotton blending machines, etc., the optical path or the entire optical path length can reach at least about 550 mm. Therefore, it can cover an observation area of ​​at least approximately 300 mm wide and 0.3 mm high.

[0019] In principle, the at least one camera can also be an area scan camera or a matrix camera, and it is also possible for a combination of camera devices including at least one line scan camera and at least one area scan camera or matrix camera. Each camera may 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 may also be provided, which the camera can align with.

[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 observation area and deflection device can be arranged in the lower section, or vice versa. To increase the overall distance between the camera device, the deflection device, and the observation surface, other components can be sequentially arranged deep within the internal space, such as an evaluation unit and a control unit for determining material quality, especially for identifying foreign objects, particularly those with brightness and / or color deviations. In particular, the evaluation unit and / or control unit can be arranged between the camera device and the cover element.

[0021] To isolate the observation area from ambient or external light, the cover element can be constructed to be opaque in the section containing the observation area (especially the lower or upper section). This avoids interfering light reflections in the observation area.

[0022] Furthermore, the opening closing device may have a visible section located above and / or below the observation area. In other words, the observation area (where the cover element may be designed to be opaque) is located outside the visible section. Within the visible section, the separating element and the cover element may be constructed to be transparent. In particular, this visible section is arranged between the upper and lower sections. Preferably, the visible section is directly adjacent to the upper section upwards and directly adjacent to the lower section downwards. In this way, the inspection device not only provides the possibility of optical inspection of the fibrous material using a camera device, but also serves additionally as an observation opening through which an operator can see from the outside into the feed box of the pretreatment machine to inspect the fibrous material passing through the separating element of the opening closing device. In principle, the visible section may also be the upper section, in which the camera device can be arranged, or it may extend over the middle and upper sections. Furthermore, the entire cover element may also be designed to be transparent, for example, made of transparent glass or plastic. Regarding the height of the observation area, especially in the lower section of the opening closing device, the cover element made of transparent material can be coated, painted, or treated similarly to isolate the observation area from the influence of interfering external light.

[0023] The opening closure device can serve as a carrier for other auxiliary sensing mechanisms. Specifically, an idle monitoring device for the cotton feed box can be arranged on the outside of the separating element and / or within the internal space of the opening closure device. For example, this could include a grating or a photoelectric switch.

[0024] Furthermore, the opening closing device may include a frame that surrounds the partition element and the cover element. Thus, the opening closing device can be installed in the housing opening, for example, like a rigid window sash. Additionally, hinge devices can be provided for pivotally securing the opening closing device, particularly the frame, to the housing of the pretreatment machine within the housing opening area. Therefore, the opening closing device can be designed to be installed in the housing opening like a pivotable window sash, a pivotable door, a pivotable flap, etc. Instead of a hinged arrangement, the opening closing device can also be installed rigidly or immovably in the housing opening, for example, like a rigid window.

[0025] Preferably, the inspection device can operate as a structural unit, which can be installed into an opening in the housing like a window or door. Therefore, the inspection device can be referred to as a smart maintenance door or smart maintenance window. To operate the inspection device, it can be connected to a power source, particularly the power source of the pretreatment machine. Furthermore, devices for data transmission can be provided.

[0026] For example, the camera device may have an interface for connecting to an evaluation unit and / or a control unit. The inspection device may include an evaluation unit, which may in particular be housed within the internal space of an opening-closing device. The control unit may be a control unit of a pre-processing machine or a higher-level equipment control device.

[0027] Maintenance windows that can be replaced by inspection devices typically have an external width of at least about 400 mm and an external height of at least about 800 mm. Preferably, the external dimensions of the inspection device are chosen such that the inspection device can be fitted into an existing housing opening instead of the maintenance window. In particular, the inspection device, especially the opening closing device, can have an external width of 200 mm to 600 mm and an external height of 400 mm to 1200 mm. Preferably, the external width is in the range of 300 mm to 500 mm, and the external height is in the range of 600 mm to 1000 mm.

[0028] Another solution to the aforementioned task is to use the aforementioned inspection device to close the housing opening already present in the pretreatment machine, through which the feed box for the fiber material can be seen from the outside. The same advantages associated with the inspection device according to the invention can be obtained by applying the invention, and therefore briefly referred to above. It goes without saying that all the mentioned embodiments can be adapted to this application, and vice versa.

[0029] The application of this invention is based on the following fundamental concept: conventional pretreatment machines always have at least one housing opening, into which an observation window or similar device is typically installed, allowing the operator to view the cotton feed box from the outside. According to this invention, an inspection device is installed in the existing housing opening, replacing the conventional observation window.

[0030] Preferably, the inspection device is applied to a pretreatment machine in which the fibrous material accumulates at least briefly in the feed box. The fibrous material can then slowly pass through the inspection device, wherein a particularly brief period of stillness is acceptable. This optimizes quality data, such as the detection of foreign matter content. The fibrous material may exist in a fibrous form in the feed box.

[0031] Another solution to the aforementioned task lies in a pretreatment machine having a housing that surrounds at least one feed box for fibrous material and has at least one housing opening through which the feed box can be viewed from the outside; and having at least one of the aforementioned inspection devices, which is inserted into at least one of the at least one housing opening. The same advantages as the inspection device or application according to the invention can be obtained with the pretreatment machine according to the invention, and therefore reference is briefly made to the above description. It goes without saying that all the mentioned embodiments can be adapted to a pretreatment machine, and vice versa.

[0032] This pretreatment machine can be a textile preparation machine, especially a bag-grabbing machine (e.g., Trützschler General Bag-grabbing Machine BO-U), a cotton cleaner (e.g., Trützschler General Cotton Cleaner CL-U), an opening machine (e.g., Trützschler General Opener TO-U), a cotton blending machine (e.g., Trützschler General Cotton Blending Machine MX-U), a wadding blending machine (e.g., Trützschler T-Blend), or a flatbed carding machine (e.g., Trützschler TC21). Alternatively, this pretreatment machine can also come from the nonwoven fabric production field, such as an opening machine (e.g., Trützschler General Fine Opener TBL-FB or TBL-FO), a blending bin (e.g., Trützschler TBL-BB), or a roller carding machine (e.g., Trützschler TWF-NC).

[0033] When operating such a pretreatment machine, the fibrous material slowly passes over the outside of the separating element. In particular, the feed box is a feed box with a metering device arranged on its bottom side to allow for the metered removal of the fibrous material from the feed box. This metering device can be, for example, a roller feed section and / or an opening roller. Within the feed box, the transport speed of the fibrous material as it passes through the observation area ranges from a few millimeters per minute to a few centimeters per minute. Typically, the transport speed ranges from 20 millimeters per minute to 800 millimeters per minute. Brief stops in the flow of the fibrous material are also possible. To optimize the identification of quality characteristics (such as foreign matter content) at slow transport speeds, it may be advantageous to equip the pretreatment machine with multiple inspection devices. In particular, each feed box may be equipped with two of these inspection devices, arranged facing each other on the front and rear sides of the pretreatment machine.

[0034] Furthermore, a pressure sensor can be arranged in at least one feed box to measure dynamic pressure. Using the measured dynamic pressure, the output value of the evaluation unit can be corrected to a characteristic parameter independent of dynamic pressure. For this purpose, a calibration curve can be stored in the evaluation unit. This is because the amount of foreign matter visible in the observation area or in the image captured by the camera device largely depends on the material resolution of the fiber material. A loose, well-resolution layer of material will present fewer foreign matter to the camera device in the feed box. Conversely, if the material in the feed box is compressed at a higher pressure by the loading of transport air, significantly more foreign matter will be displayed in the observation area or in the image, and thus in such a plane. Therefore, fluctuating dynamic pressure can significantly affect the detection of foreign matter content. The at least one pressure sensor can be arranged above a designated maximum material level in the at least one feed box. The at least one inspection device can be arranged below the maximum material level. To specify the maximum material level, a grating or photoelectric switch can be arranged in the at least one feed box. The maximum material level can be determined by the installation height of the grating or photoelectric switch.

[0035] Another solution to the above-described task lies in an apparatus comprising a plurality of the aforementioned pretreatment machines. The same advantages associated with the inspection apparatus or application or pretreatment machines according to the invention can be obtained by the apparatus according to the invention, and thus briefly referred to herein. It goes without saying that all the mentioned embodiments can be adapted to this apparatus, and vice versa.

[0036] In this way, within the equipment, multiple pre-processing machines, and in particular, each machine is equipped with at least one inspection device. Therefore, defined quality characteristics of the fiber material, such as foreign matter content, can be analyzed at multiple process points within the equipment. Consequently, based on the detected raw material quality, subsequent machines can automatically adapt to changes in raw material quality. In other words, for automated optimization of the equipment, inspection devices are set up to analyze the fiber material in the receiving space of the pre-processing machine in terms of specified quality characteristics (such as foreign matter content, also known as interfering particle content), so that upstream and / or downstream textile preparation machines can automatically adapt to changes in raw material quality based on the detected quality characteristics.

[0037] The pretreatment machines of this equipment cover the processing line in textile preparation in a purposeful manner, so the equipment can include different types of pretreatment machines. In this way, the quality of the fiber material can be detected at multiple process points on the processing line so as to cope with the changing raw material quality by adapting the pretreatment machines during processing.

[0038] Furthermore, it can be specified that at least one pretreatment machine or device has at least one waste sensor device configured to analyze the waste composition, including foreign matter and good fibers, separated from the fibrous material using at least one optical sensor. By integrating the waste sensor device into the pretreatment machine, it is possible to distinguish whether the raw material quality has deteriorated or whether the cleaning efficiency of the pretreatment machine has decreased. Raw material quality is monitored by an 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 the waste duct, particularly in the waste duct of a pretreatment 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 undesirable waste (fibers). Preferably, the pretreatment machine can automatically adjust machine components or cleaning components that affect waste separation. For example, in a pre-cleaning cotton machine, the influence on waste separation can be the rotational speed of the opening roller or the opening width of the separation grid. Furthermore, adjustable separation blades, adjustable vanes, suction hoods, etc., tangentially attached to the opening roller are also possible. In addition, the pretreatment machine can also be equipped with multiple other adjustable cleaning components.

[0040] Another solution to the aforementioned task lies in a method for optically inspecting fibrous materials in a pre-processing machine or apparatus as described previously, wherein the method comprises the following steps: capturing an image of the fibrous material or its surface passing through an observation area using a camera device of a suitable inspection apparatus; evaluating the captured image by at least one evaluation unit to determine the quality characteristics of the fibrous material, particularly the current foreign matter content; and outputting an output value, which in particular includes the current foreign matter content in the fibrous material. The same advantages associated with the inspection apparatus or application or pre-processing machine or apparatus according to the invention can be obtained by the method according to the invention, and thus briefly referred to herein. It goes without saying that all the mentioned embodiments can be adapted to this method, and vice versa.

[0041] Images can be generated within consecutive time intervals. Furthermore, the method may include at least one of the following steps: comparing an output value with at least one specified and / or previous initial value, particularly the foreign matter content; determining the current waste composition using 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; and 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. Similarly, the range can also correspond to, for example, a percentage deviation of ±10%, wherein larger or smaller ranges can be adjusted according to the operator's requirements for the pretreatment machine.

[0042] Furthermore, the method may also include the following steps: 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 the specified and / or previous waste value, automatically changing the adjustment of at least one cleaning element or at least one machine element affecting waste separation in the corresponding pretreatment machine and / or the textile preparation machine downstream of the corresponding pretreatment machine and / or the textile preparation machine upstream of the corresponding pretreatment machine. This enables particularly effective regulation of quality fluctuations, especially when the foreign matter content in the raw material varies. Similar to the above, the corresponding defined range can be zero, or correspond to, for example, a percentage deviation of ±10%, wherein larger or smaller ranges can also be adjusted according to the operator's requirements for the pretreatment machine.

[0043] By way of example, assuming that during the operation of the pretreatment machine, on the one hand, the quality of the raw material decreases, and on the other hand, the cleaning efficiency of the pretreatment machine decreases, then without an inspection device, the decrease in raw material quality remains undetected. Another scenario is that the amount of foreign matter discharged from the cleaning section 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, especially the cotton cleaner, must be re-optimized. Preferably, the waste sensor device is configured to perform optimized operation when a change in raw material quality is detected by the at least one inspection device. Therefore, optimal adjustments depend on the material and contaminants and can be adapted during operation as raw material characteristics change.

[0044] The waste sensor device can be configured to perform optimized operation, in which at least one cleaning element gradually moves from a first terminal position without separating impurities to a second terminal position separating impurities and fibers. This is because the cleaning effect of the pretreatment machine depends on the adjustment of its cleaning elements. Sensor signals are detected and evaluated. The optimized operation can end from a point where excessive fiber material is separated disproportionately relative to the foreign matter content. For example, in a cotton cleaner like the Trützschler CL-U, the first cleaning element can move tangentially in the form of a blade, thus opening or completely or partially closing the cleaning point. A second cleaning element, which may be a pivotable blade, can rotate around its center of rotation, thus also opening or completely or partially closing the cleaning point here. In this way, only a slight or no cleaning effect is achieved at the first terminal position, while at the second terminal position, although the cleaning effect may be better, excessive good fibers, in addition to foreign matter, may also enter the waste material. Attached Figure Description

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

[0046] Figure 1 A schematic simplified illustration of a preprocessing machine according to a first embodiment of the invention is shown, wherein the preprocessing machine includes an inspection device according to the invention, the inspection device having a camera, a deflection device and two illumination elements;

[0047] Figure 2 A partially sectional side view of the preprocessing machine is shown;

[0048] Figure 3 An enlarged partial view of the preprocessing machine is shown in a schematically simplified cross-sectional view;

[0049] Figure 4An enlarged partial view of the preprocessing machine is shown within the area of ​​the inspection device, wherein the camera is adjusted to a first focal length;

[0050] Figure 5 Show Figure 4 An enlarged partial view, in which the camera is adjusted to a second focal length;

[0051] Figure 6 A schematic diagram showing the flowchart of the preprocessing machine during automatic operation;

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

[0053] Figure 8 Show Figure 6 This is a schematic diagram of another sub-step in the flowchart, which involves performing an optimized run;

[0054] Figure 9 An enlarged partial view of a preprocessing machine according to an alternative embodiment is shown in a schematically simplified cross-sectional view, wherein the preprocessing machine includes a plurality of inspection devices.

[0055] Figure 10 An enlarged partial view of the preprocessing machine within the area of ​​the inspection device is shown according to an alternative embodiment with two cameras.

[0056] Figure 11 An enlarged partial view of a preprocessing machine according to another embodiment is shown in a schematically simplified cross-sectional view.

[0057] Figure 12 A side view of a pretreatment machine according to another embodiment of the invention is shown. Detailed Implementation

[0058] The solutions according to the present invention include different combinations of features, particularly defined by the following sequentially numbered embodiments:

[0059] 1. An inspection device (30) for identifying foreign matter in fibrous material contained in a feed box (2) of a pretreatment machine (1; 100), particularly a textile preparation machine, wherein the inspection device (30) comprises: - an opening closing device (31) for closing an opening (27) of the housing of the pretreatment machine (1; 100), through which the feed box (2) can be seen from the outside, wherein the opening closing device (31) has a separating element (32) and a cover element (33) arranged on the separating element (32), the separating element (32) having a transparent observation area (39) defining an observation plane (E), wherein an internal space (37) is formed between the separating element (32) and the cover element (33); and - a camera device (38) arranged in the internal space (37), 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 internal space (37) of the opening closing device (31), which deflects the light path (42) originating from the observation area (39) toward the camera device (38).

[0060] 2. The inspection device (30) according to embodiment 1 is characterized in that the deflection device (41) has a reflective surface (47), wherein the incident angle between the optical path (42) and the surface normal of the reflective surface (47) is 45 degrees, or wherein the incident angle between the optical path (42) and the surface normal of the reflective surface (47) is greater than 45 degrees and less than 85 degrees.

[0061] 3. The inspection device (30) according to embodiment 1 or 2 is characterized in that the camera device (38) includes at least one line scan camera (54; 54', 54'').

[0062] 4. The inspection device (30) according to any one of embodiments 1 to 3 is characterized in that an illumination device (50) for illuminating the fibrous material (3) passing through the observation area (39) is arranged in the internal space (37), wherein the illumination device (50) extends over the entire width of the observation area (39).

[0063] 5. The inspection device (30) according to any one of embodiments 1 to 4 is characterized in that the opening closing device (31) has an upper section (45) and a lower section (46) axially spaced from the upper section (45) about 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).

[0064] 6. The inspection device (30) according to any one of embodiments 1 to 5 is characterized in that the cover element (33) in the lower section (46) is constructed to be opaque.

[0065] 7. The inspection device (30) according to any one of embodiments 1 to 6 is characterized in that the opening closing device (31) has a visible section (59) in which the separating element (32) and the cover element (33) are constructed to be transparent, and in particular, the visible section (59) is arranged between the upper section (45) and the lower section (46).

[0066] 8. The inspection device (30) according to any one of embodiments 1 to 7 is characterized in that the opening closing device (31) has a hinge device (61) for pivotally fastening to the pretreatment machine (1; 100) in the region of the housing opening (27).

[0067] 9. The inspection device (30) according to any one of embodiments 1 to 8 is used to close the housing opening (27) that already exists in the pretreatment machine (1; 100), through which the cotton feeding box (2) for the fiber material (3) can be seen from the outside.

[0068] 10. A pretreatment machine (1; 100) having a housing (26) surrounding at least one feed box (2) for fibrous material (3) and having at least one housing opening (27) through which the feed box (2) can be seen from the outside; and the pretreatment machine having at least one inspection device (30) constructed according to one of embodiments 1 to 8 and inserted into at least one housing opening of the at least one housing opening (27).

[0069] 11. The pretreatment machine (1; 100) according to embodiment 10 is characterized in that a pressure sensor (29) for measuring dynamic pressure is arranged in the at least one feeding box (2), wherein the pressure sensor (29) is arranged above a specified maximum material level (Fmax) of the at least one feeding box (2), and the at least one inspection device (30) is arranged below the maximum material level (Fmax).

[0070] 12. The pretreatment machine (1; 100) according to embodiment 11 is characterized in that a grating (28) or a photoelectric switch is arranged in the at least one cotton feeding box (2), wherein the installation height of the grating (28) or the photoelectric switch specifies the maximum material level (Fmax).

[0071] 13. An apparatus comprising a plurality of pretreatment machines (1; 100) according to any one of embodiments 10 to 12.

[0072] 14. A method for identifying foreign matter in a fibrous material (3), the fibrous material being contained in a feed box (2) of a pretreatment machine (1; 100) according to one of embodiments 10 to 12 or in a feed box (2) of a device according to embodiment 13, wherein the method comprises the following steps: - capturing (72) an image of the fibrous material (3) passing through an observation area (39) by means of a camera device (38) of a corresponding inspection device (30); - evaluating (73) the captured image by at least one evaluation unit (57) to determine the content of foreign matter in the fibrous material (3); - outputting (76) at least one output value, the output value including the content of foreign matter in the fibrous material (3).

[0073] 15. The method according to embodiment 14, characterized in that at least one of the pretreatment machines (1; 100) or the equipment has at least one waste sensor device (22), the waste sensor device being configured to determine the waste composition of waste containing foreign matter and good fibers separated from the fibrous material (3) by means of at least one optical sensor (23, 24), and the method comprising 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; - An optimized operation (92) is performed on the textile preparation machine (1; 100) downstream of the corresponding pretreatment machine (1; 100) and / or the textile preparation machine (1; 100) upstream of the corresponding pretreatment machine (1; 100), wherein, when there is a deviation between the at least one output value and the at least one initial value, the position or rotation speed of at least one cleaning element (15, 16) for separating waste from the fiber material (3) is automatically changed, 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).

[0074] exist Figure 1 and Figure 2 The diagram shows a pretreatment machine 1 according to a first embodiment of the invention, which is configured as a cleaning machine, i.e., a cotton cleaner. Further details and possible modifications are shown in... Figures 3 to 5The figure shows the orientation of the preprocessing machine 1 in space. In the figure, to illustrate the orientation of the preprocessing machine 1 in space, the longitudinal direction X, the transverse direction Y, and the vertical direction Z are drawn. These directions are defined according to the Cartesian coordinate system associated with the preprocessing machine 1 and are indicated by corresponding arrows. Concepts such as "below," "down," "above," or "up" are used here to indicate spatial description relative to the vertical direction Z. The preprocessing machine 1 can be placed on a fixed base surface located within a horizontal plane opened by the longitudinal direction X and the transverse direction Y.

[0075] exist Figure 1 As can be seen, the pretreatment machine 1 has a feeding box 2. The feeding box 2 is connected to the inlet 4, through which the cotton can typically be fed from the upstream pretreatment machine (e.g., Figure 12 The blending machine shown here (here, the Trützschler general blending machine MX-U) pneumatically introduces fiber material 3 supplied in wadding form. A dust removal device 6 is arranged in the upper part 5 of the feed box 2, 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 exemplarily 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.

[0076] The opening roller 14 is sequentially equipped with a first cleaning element 15 and a second cleaning element in its rotational direction. This arrangement is described in the applicant's published document DE102012012254A1, which is incorporated herein by reference in its entirety. The first cleaning element 15 is at least substantially movable tangentially relative to the circumference 17 of the tooth tip of the cardioid 18 of the opening roller 14 along the direction of the double arrow A, in order to adjust the channel of the cleaning position. The waste separated by the cleaning elements 15 and 16 enters the waste branch 21 through the suction hoods 19 and 20. A piping system is connected again after the second cleaning element 16 along the rotational direction of the opening roller 14, through which the cleaned fibrous material 3 can be transported to a subsequent pretreatment machine (not shown), such as a foreign matter separator, such as Trützschler's SP-FPU, T-ScanTS-T3, or T-ScanTS-T5. Figure 1 The arrow T indicates the direction of transport of the cleaned fiber material to the subsequent pretreatment machine.

[0077] exist Figure 2As can be seen, waste material sucked into waste branch 21 through suction hoods 19 and 20 passes through waste sensor device 22. Waste sensor device 22 has an optical measurement device, with a sensor 23 and 24 for each suction hood 19 and 20, specifically a brightness sensor that observes the respective suction hood 19 and 20 through a transparent partition. Sensors 23 and 24 can detect waste material transported through the waste pipe 25 of waste branch 21 from suction hoods 19 and 20, allowing for the identification of good fibers within the waste stream. By evaluating the measurement results, the proportion of good fibers in the waste or the waste composition containing both foreign matter and good fibers can be determined.

[0078] Above the roller feed section 9, a housing opening 27 is constructed in the housing 26 surrounding the feed box 2 of the pretreatment machine 1. Above the housing opening 27, a grating 28 or photoelectric switch connected to a machine control device (not shown) is arranged as a level limiter. Once the level F of the fiber material 3 in the feed box 2 rises to the mounting height of the grating 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 mounting height specifies the maximum level Fmax. Furthermore, above the grating 28, a pressure sensor 29 is arranged inside the feed box 2. This pressure sensor can be designed as a differential pressure sensor to measure the difference between the spatial pressure present inside the feed box 2 and the ambient pressure present outside the feed box 2. Thus, the effect of the dynamic pressure generated by the transport air flowing into the feed box 2, which applies pressure from above and compresses the fiber material 3, can be determined. Instead of a differential pressure sensor, two separate pressure sensors can also be used.

[0079] The inspection device 30 according to the present invention is installed in the housing opening 27 of the housing 26 of the pretreatment machine 1. The structure and function of the inspection device will be described in detail below. Figure 1 and Figure 2 As can be seen, the inspection device 30 is exemplarily constructed here as a pivotable entry or inspection door, which is hinged to the housing 26 by means of a hinge device 61. Furthermore, a mechanical locking device 62 may be provided to lock the inspection device 30 in its closed state. In principle, the inspection device 30 may also be a fixed window without the hinge device 61 and the locking device 62.

[0080] exist Figure 3As can be seen, the inspection device 30 has an opening closing device 31, which includes a separating element 32 and a cover element 33. The separating element 32 is designed as a plate and ends flush with the housing wall 34 surrounding the opening 27 of the feed box 2. During the operation of the pretreatment machine 1, the fibrous material 3 passes through or sweeps along the inner side of the housing wall 34 and the outer side 35 of the separating element 32 facing the feed box 2 in the direction of the arrow (reference numeral 63). Furthermore, the opening closing device 31 may have a frame 36 surrounding the separating element 32 and the cover element 33 for securing the opening closing device 31 to the housing 26. Therefore, the opening closing device 31 can be used like a fixed window, wherein, in order to construct the opening closing device 31 as a pivotable window or flap, a pivoting or flipping device is also possible in principle. Similarly, the frame 36 can be multi-part, having a frame portion fixed to the housing 26 and a separate frame portion comprising a unit consisting of a partition element 32 and a cover element 33, so that the unit can be easily removed and thereby provides an inlet for inspection or maintenance work on the cotton feeding box 2. An internal space 37 is constructed between the partition element 32 and the cover element 33. To seal the housing opening 27 and the internal space 37 for dust and moisture protection, a sealing element (not shown) can be provided in a manner known per se.

[0081] A camera device 38 is arranged within the internal space 37 of the opening-closing device 31 to capture images of the fibrous material 3 passing through the observation area 39 defined by the separating element 32 in the cotton feeding box 2 along the direction of arrow 63. For this purpose, the separating element 32 is constructed to be transparent in the observation area 39, wherein, as exemplarily shown here, the entire surface of the separating element 32 is constructed to be transparent. The outer side 35 of the separating element 32 defines an observation plane E, to which the optical axis 40 of the camera device 38 is oriented parallel. Furthermore, a deflection device 41 is housed within the internal space 37 of the opening-closing device 31, which is arranged within the field of view of the camera device 38 and deflects the light path 42 emanating from the observation area 39 toward the camera device 38. Exemplarily, the deflection device 41 includes a mirror with a reflective surface 47. Both the incident and exit angles are 45 degrees, thus deflecting the light path 42 by 90 degrees. Figure 3 As can be seen, the first optical path segment 43 of the optical path 42 extends perpendicularly to the observation plane E, and the optical path 42 has a second optical path segment 44 oriented parallel to the optical axis 40 after deflection.

[0082] Here, exemplarily, the camera device 38 is arranged in the upper section 45 of the opening-closing device 31. Correspondingly, the deflection device 41, spaced apart from the camera device 38, is positioned in the lower section 46 of the opening-closing device 31, and the observation area 39 is also constructed in this lower section. In principle, the opposite arrangement is also possible, where the camera device 38 can be arranged in the lower section 46 while 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 scan line, can be specified, which, when appropriate, corresponds at most to the net width 49 of the frame 36. Figure 4 and Figure 5 In this configuration, the camera device 38 is arranged at two different distances relative to the deflection device 41. The camera device 38 is fixed in the respective positions. Within the internal space 37, a guide device (not shown) may be provided, which may include, for example, a guide rail, a rod, a plate with a perforated pattern, or the like, to orient the camera device 38 and adjust the inspection width by means of its distance from the deflection device 41.

[0083] To illuminate the fibrous material 3 passing through the observation area 39, an illumination device 50 is arranged in the internal 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 an obliquely upward or downward direction. Therefore, the observation area 39 is positioned between the two illumination elements 51 and 52. Along the optical axis 40, a deflection device 41 is arranged between the camera device 38 and the lower illumination element 52, while the upper illumination element 51 is arranged between the camera device 38 and the deflection device 41. The two illumination elements 51 and 52 are constructed as strips and extend at least along the detection width 48 of the camera device 38. The illumination elements 51 and 52 may include multiple LED light sources 53 with lenses. To avoid light reflection, the angle of incidence deviates from the surface normal of the observation plane E and, exemplarily, intersects the observation plane E within a range of 20 to 80 degrees. In order to isolate the observation area 39 from ambient light or external light, the cover element 33 in the lower section 46 can be constructed to be opaque.

[0084] The camera device 38 has a camera 54 with a lens 55, which is, for example, a line scan camera, although an area scan camera could also be used in principle. The camera 54 is connected to an electronic evaluation unit 57 via a data cable 56, which analyzes the image data received by the camera device 38. The evaluation unit 57 is configured to evaluate the quantity, frequency, and / or total area of ​​foreign objects in the fiber material using image processing methods, so as to output the foreign object content in the fiber material 3. The evaluation unit 57 can identify foreign objects, for example, based on differences in brightness and / or color. Exemplarily, the evaluation unit 57 is arranged in the upper section 45 within the internal space 37. In this way, the fiber material can be optically inspected from the machine side equipped with the inspection device 30 to identify foreign objects in the fiber material 3.

[0085] The embodiment of the pretreatment machine 1 shown here has only one inspection device 30. The housing wall 58 opposite to the inspection device 30 is constructed to be closed here, however, it may have an access port or the like in a manner known per se, into which the inspection device 30 may also be installed in principle.

[0086] The inspection device 30 may have an interface that allows it to be connected to a power supply system and / or a bus system, particularly a fieldbus, after being inserted into the housing opening 27. This interface may include, for example, plug contacts, connection points, etc., which connect to at least one mating element located 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 powered and / or coupled to a control unit to, for example, transmit the output value of the evaluation unit 57 to the control unit. The control unit may be provided to the pre-processing machine or to a higher-level equipment control unit that communicates with the control units of multiple other pre-processing machines.

[0087] During the operation of the pretreatment machine 1, the fiber material 2 is pneumatically transported into the feed box 2 through the feed inlet 3. The transport air is discharged by the dust removal device 6, and the fiber material 3 accumulates in the lower part 8 of the feed box 2. Based on the slow operation of the roller feed section 9, the fiber material accumulates in the feed box 2, where the material level F is typically above the observation area 39 and below the grating 28. At high production rates, there may be brief periods where the material level F is below the observation area 39. To avoid capturing images at this time, a material level sensor, such as another grating or a photoelectric switch, can be installed.

[0088] exist Figure 6The diagram shows a possible flowchart of the automatic operation of the pretreatment machine 1. With start 65, the cleaning elements 15 and 16 have been optimized for specified initial values ​​using an initial optimization run. These specified initial values ​​may correspond to the foreign matter content manually entered by the operator based on the quality of the purchased or surveyed raw materials. The optimization run can be performed during the continuous operation of the pretreatment machine 1, wherein the roller feed section 9 and the opening roller 14 continue to be rotatably driven. During the optimization run, the optical sensors 23 and 24 of the waste sensor device 22 check the waste composition of the waste sucked through the suction hoods 19 and 20. At the start of each optimization run, the first cleaning element 15 can first move to a first position where the cleaning point or cleaning port is closed. At the first position, the foreign matter separation rate is initially low. Then, the first cleaning element 15 can move along double arrow A and gradually open the cleaning port, wherein the foreign matter content increases. From a certain point, the ratio of good fiber content to foreign matter content always further increases. Then, the first cleaning element 15 moves to the position where the ratio between foreign matter and good fiber is most favorable in this optimization run. The ratio of foreign matter to good fibers obtained from the optimized operation is stored as a waste value. Therefore, based on the parameters stored in the control unit or specified by the operator of pretreatment machine 1, the machine components affecting the waste composition (here, cleaning elements 15 and 16) can be automatically adjusted for an extended period until the desired waste quality is achieved. The optimized operation performed based on the initial values ​​thus optimizes the cleaning efficiency of pretreatment machine 1.

[0089] After the automatic operation begins (65 minutes), step 70 detects or monitors the current or actual foreign matter content in the fiber material 3. Step 70 includes several sub-steps, which... Figure 7 The flowchart illustrates this process. After foreign object detection begins at step 71, camera device 38 captures an image of the fibrous material 3 behind observation area 39 in sub-step 72, where illumination device 50 illuminates observation area 39 using reflected light during the capture. Subsequently, evaluation unit 57 evaluates the image data transmitted by camera device 38 regarding the detected image in sub-step 73. Here, image processing methods are used to evaluate the received image data in terms of the number, frequency, and / or total area of ​​foreign objects in fibrous material 3. Typically, foreign objects such as stems, leaves, or general "garbage" particles appear as areas darker than the cream-colored to white fibrous material 3. Since a binary state is almost inherent, for example, through thresholding, the found foreign objects can be subdivided against the bright background of fibrous material 3. The scene can then be conventionally decomposed to extract objects with features such as size, area, and outline. The foreign object content can be determined by counting dark objects or by accumulating area. Furthermore, size histograms can be generated or objects can be classified into groups such as garbage, stems, and leaves.

[0090] In substep 74, it is queried whether the image area detected by camera device 38 corresponds to a defined minimum area. For generating output values ​​or measurements from image data (values ​​that reliably or statistically definitively reflect the foreign matter content in the fibrous material), it has proven advantageous when the minimum area detected by camera device 38 reaches a defined minimum. Very high accuracy is achieved when the minimum area is greater than 2 square meters, and more preferably at least about 3 square meters. Since the detection area of ​​line scan camera 54 is smaller than the minimum area, for example only 90 square millimeters, other images are captured for an extended period 72 and evaluated 73 until the defined minimum area is reached.

[0091] In order to respond as quickly as possible to varying foreign matter content in the fibrous material 3 by adjusting the cleaning elements 15 and 16, one objective is to detect the defined minimum area of ​​the fibrous material 3 in the shortest possible time, without requiring multiple foreign matter detections. Since the pretreatment machine 1 shown here has only one single inspection device 30, the required minimum area must be detected by an image from one of the camera devices 38. For example, the detection area of ​​the camera device 38 can be increased by increasing the distance between it and the deflection device 41 or the observation area 39, thereby allowing a larger area to be detected with a single image. The image capture frequency depends on the transport speed and can only be increased within a limited range to avoid multiple counts of the same foreign matter. For example, assuming a transport speed of 120 to 360 mm per minute, an image capture frequency of 13 to 80 Hz can be used. For example, assuming the detection area or image area of ​​one image from camera device 38 is only 90 square millimeters, the measurement time to reach the minimum area, for example, 3 square meters, is 14 minutes. Therefore, higher transport speeds achievable through higher productivity allow for higher image capture frequencies, thereby enabling faster detection of the minimum area. Therefore, the evaluation unit 57 considers images constructed in a linear array, as is common in linear scan cameras, when evaluating images and uses image processing algorithms to evaluate these images in terms of foreign matter. The evaluation results of each image are accumulated to improve the accuracy of determining the foreign matter content in the fiber material 3.

[0092] In sub-step 75, evaluation unit 57 considers the dynamic pressure in feed box 2 measured by pressure sensor 29 when evaluating the image. The transport air flowing into feed box 2 always causes a certain degree of compression of the fiber material 3 in feed box 2, which may affect the accuracy of the output value. To minimize and eliminate this effect as much as possible, pressure sensor 29 is coupled to evaluation unit 57. Using the measured dynamic pressure and the calibration curve stored in evaluation unit 57, the output value of evaluation unit 57 can be corrected to a characteristic parameter independent of dynamic pressure. Evaluation unit 57 outputs its corrected output value to the control unit of preprocessing machine 1. The corrected output value is transmitted to the control unit, see sub-step 76. Foreign matter content detection ends at 77. The foreign matter detection process according to sub-steps 71 to 77 can be repeated periodically. Multiple detection processes can also be performed simultaneously in a time-staggered manner, thereby enabling the current foreign matter content to be provided within a shorter time interval using updated output values.

[0093] According to Figure 6 The flowchart shown shows that step 80 follows step 70, in which the waste composition is determined using waste sensor device 22. Waste sensor device 22 can periodically and, in principle, continuously monitor the waste composition, so step 80 can also be performed simultaneously with step 70. Waste sensor device 22 determines the composition of the waste or the content of good fiber by means of optical sensors 23 and 24, which are drawn through suction hoods 19 and 20.

[0094] Based on the particularly corrected output values ​​and waste composition, it can be determined in step 85 whether the cleaning of pretreatment machine 1 needs to be optimized (“Yes”). If none of the criteria mentioned below are met, the cleaning elements 15 and 16 are currently optimized and do not require optimization at present (“No”), and the method continues in a loop containing steps 70, 80, and 85.

[0095] If any of the criteria below are met, optimization is performed in step 90:

[0096] If the corrected output value remains unchanged compared to the initial value set or specified in the previous or initial optimization run, or is at least within the specified tolerance range around the initial value, but the scrap composition or scrap amount deviates from the scrap value set in the previous optimization run and is in particular outside the specified tolerance range around the scrap value;

[0097] If the composition or amount of scrap remains unchanged or at least within the specified tolerance range around the scrap value compared to the scrap value set in the previous or initial optimization run, however, especially if the corrected output value is observed to change over time because the output value is outside the specified tolerance range, a sudden increase in the output value is detected or a continuous increase or decrease is identified in the observation of the integral over time.

[0098] If not only is the corrected output value outside the specified tolerance range around the initial value, but the scrap composition or scrap amount is also outside the specified tolerance range around the scrap value.

[0099] Optimization 90 includes multiple sub-steps, these sub-steps in Figure 8 The flowchart illustrates this. After starting at step 91, an optimization run 92 is executed, in which the positions of cleaning elements 15 and 16 are changed while the changing waste composition is monitored using waste sensor device 22. Here, based on parameters stored in the control unit or specified by the operator of pretreatment machine 1, the machine components (here, cleaning elements 15 and 16) affecting the waste composition are automatically adjusted for an extended period until the desired waste quality is achieved for the detected output value, which reflects the current waste content. Instead of a complete optimization run 92 (in which the machine first proceeds to the first position), it is also possible to start from the currently adjusted operating point and check whether the separation efficiency is improved by slightly adjusting cleaning elements 15 and 16. In sub-step 93, the current output value, representing the current foreign matter content in the fiber material 3, is detected. In sub-step 94, the current waste composition, representing the ratio between foreign matter and good fiber, is detected. In sub-step 95, the current output value is set as the initial value and the current waste composition is set as the waste value and thus used as a reference value for subsequent decisions according to step 85. Optimization 90 ends at 96. Preferably, optimization 90 is performed fully automatically and is started and monitored by a control unit. In principle, operator confirmation may be required before each optimization run. Each optimization run can be visually displayed and / or digitally recorded.

[0100] To ensure that the output values ​​are always as up-to-date as possible, the foreign matter detection process 70, with sub-steps 71 to 77, can be repeated periodically as a background process. Similarly, the waste composition 80 can be continuously monitored.

[0101] 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 feed box 2. For this purpose, the opening closing device 31 can have a viewing section 59 in which both the cover element 33 and the partition element 32 are designed to be transparent, and the components constructed in the internal space 37 do not obstruct the view of the fiber material 3 from the outside. Preferably, the viewing section 59 is the middle section of the opening closing device 31, arranged between the upper section 45 and the lower section 46. When the operator himself identifies a change in the foreign matter content inside the feed box 2 by observing it from the outside through the viewing section 59, the optimization 90 can also be manually triggered, for example, through an application on a mobile terminal device, the operating terminal of the pretreatment machine 1, and / or a higher-level control unit.

[0102] exist Figure 9 An alternative embodiment of the pretreatment machine 1 is shown, which largely corresponds to the aforementioned embodiment, and thus reference is made above to the commonalities. The difference is that the pretreatment machine 1 has multiple (e.g., two) inspection devices 30. These two inspection devices 30 are housed in housing openings 27 in two opposing housing walls 34, 58. By taking images of the surface of the fiber material 3 from multiple observation areas 39, changes in the raw material quality can be detected more accurately and quickly, because multiple (two) camera devices 38 simultaneously contribute to achieving the minimum area (sub-step 74). Therefore, this process largely corresponds to... Figures 6 to 8 The process is illustrated below. Each camera device 38 is equipped with an evaluation unit 57, which analyzes the image data of the associated camera device 38. The evaluation unit 57 transmits its results to another or a higher-level evaluation unit 60 via a drawn data line, where the results are aggregated. This reduces the required measurement time; in the case of using two camera devices 38, the required measurement time is halved.

[0103] exist Figure 10Another embodiment of the inspection device 30 is shown, which largely corresponds to the aforementioned inspection device 30, and thus refers to the description above regarding the commonalities. The only difference is that the camera device 38 of the corresponding inspection device 30 here has two cameras 54', 54'' (e.g., line scan cameras) instead of one camera 54, each with a lens 55', 55''. Their optical paths 44', 44'' are oriented parallel to their respective optical axes 40', 40''. Instead of a line scan camera, a matrix camera or an area scan 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, based on 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 provides only a small structural height along its extension in the vertical axis Z direction). Furthermore, the line of sight from lenses 55', 55'' to the edges of a single camera image remains sufficiently steep, so that optical errors such as distortion, edge light attenuation, and decreased sharpness are negligible. Illumination device 50 covers the entire detection width 48, which, exemplarily here, corresponds to the net width 49 of frame 36.

[0104] exist Figure 11 Another embodiment of the preprocessing machine 1 is shown, which largely corresponds to the aforementioned embodiment, and thus reference is made above to the commonalities. The difference lies in the design of the deflection device 41 and the illumination device 50. The first optical path segment 43 is tilted upwards, and this first optical path segment 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 segment 44 extends parallel to the optical axis 40 of the camera device 38. The illumination device 50 has only the lower illumination element 52, which is perpendicular to the observation plane E and points towards the observation area 39, in order to exclude interfering light reflections on the transparent separating element 32, which may appear in the image of the camera device 38 or in the image data. Therefore, the incident angle and the exit angle on the mirror surface of the deflection device 41 are both greater than 45 degrees and can be 67.5 degrees, as exemplarily shown here. Thus, the deflection device 41 and the camera device 38 can be arranged closer to the separating element 32, so that the opening closing device 31 can be designed to have a flatter structure.

[0105] In Figure 10The embodiment shown is an example, but the camera device 38 can also, in principle, be arranged higher up in the internal space 37. Here, the camera device 38 is arranged between the separating element 32 and the evaluation unit 57. Through this nested arrangement, the distance of the camera device 38 from the deflection device 41 is increased, thereby increasing the detection width 48. It goes without saying that all the various features shown in the embodiment can be used interchangeably and vice versa. For this purpose, it is only emphasized by way of example that the camera device 38 is located in... Figures 1 to 8 In the illustrated embodiments, the camera device 38 can also be positioned in a nested arrangement with the evaluation unit 57 so as to move the camera device 38 upward as much as possible; or the opening closing device 31 can be designed as a rigid window or a pivotable window; and so on.

[0106] exist Figure 12 The diagram shows a pretreatment machine 100 according to another embodiment, which is configured as a cotton blending machine and has a plurality of inspection devices 30. The inspection devices 30 can be as follows: Figures 1 to 5 and Figures 9 to 11 The design is as shown in the figure, and reference is made above to the commonalities. Here, identical or modified details are given the same reference numerals. Figure 12 In this diagram, to illustrate the orientation of the preprocessing machine 100 in space, the longitudinal direction X, the transverse direction Y, and the vertical direction Z are drawn. These directions are defined according to the Cartesian coordinate system associated with the preprocessing machine 100 and are indicated by corresponding arrows. Concepts such as "below," "down," "above," or "up" are used here to indicate spatial descriptions relative to the vertical direction Z. The preprocessing machine 100 can be placed on a fixed base surface located within a horizontal plane spanned by the longitudinal direction X and the transverse direction Y.

[0107] The pretreatment machine 100 has multiple (for example, ten) feed boxes 2 arranged in a row. The feed boxes 2 are connected to a channel 101 extending above them, which is connected at its inlet side to an upstream textile preparation machine (not shown) via a feed inlet 4. Fiber material 3, typically provided in wadding form, is pneumatically introduced into the feed boxes 2 through the feed inlet 4 and the channel 101. A control mechanism (not shown) can be provided between the channel 101 and each feed box 2 in a manner known per se to control the filling of each feed box 2. Roller feed sections and opening rollers are arranged in the lower part 8 of the respective feed box 2 in a manner known per se, as in... Figure 1 and Figure 2 As shown by reference numerals 9 and 14 in the attached figures. Furthermore, a common blending channel can be arranged below the cotton feeding box 2, through which the fibrous material piled up is transported along the transport direction T from the blending channel via a piping system to a subsequent pretreatment machine, such as... Figure 1 and Figure 2 The cotton cleaning machine 1 shown in the figure.

[0108] For each feed box 2, an inspection device 30 is installed in the opening of the housing in the front housing wall 34 of the pretreatment machine 100. However, it is also possible that the pretreatment machine 100 has only one inspection device 30 in total, or that only one inspection device 30 is used to monitor a portion of the feed boxes 2. Images detected during operation are evaluated by means of an evaluation unit 57 and, if necessary, by means of at least one superior evaluation unit 60. The output values ​​can be aggregated and averaged to obtain more representative results. Parallel inspection using multiple inspection devices 30 can provide statistically more accurate data on raw material quality (especially foreign matter content) in a shorter measurement time. In addition, other inspection devices 30 can also be arranged on the rear wall of the pretreatment machine 100, such as in Figure 12 As shown on the front side. The more inspection devices 30 are provided, the shorter the measurement time can be achieved. For example, each feed box 2 can be provided with two inspection devices 30, one on the front side and the other on the rear side, so that the blending machine 100 shown here, exemplarily with ten feed boxes 2, can have, for example, twenty inspection devices 30.

[0109] By aggregating individual results (here, twenty), evaluation time can be significantly reduced. A central control unit, or one of the evaluation units, particularly the higher-level evaluation unit 60, can be responsible for aggregating the output values ​​and transmitting them to the control unit. This control unit can be configured with downstream textile preparation machines, particularly the cotton cleaner 1, which can automatically adjust the machine components affecting waste separation based on the foreign matter content detected in the blender 100, such as changing the positions of cleaning elements 15 and 16.

[0110] Figure label:

[0111] 1. Pre-processing machine 41. Deflection device

[0112] 2 cotton feeding boxes, 42 optical paths

[0113] 3 Fiber Materials 43 Optical Path Sections

[0114] 4 feed inlets, 44 optical path sections

[0115] 5 Upper Section 45 Upper Section

[0116] 6 Dust removal device 46 lower section

[0117] 7 Exhaust pipe 47 surface

[0118] 8 Lower part 48 detection width

[0119] 9-roller feed section with a net width of 49 mm

[0120] 10 supply rollers, 50 lighting devices

[0121] 11 supply rollers 51 lighting elements

[0122] 12 feed rollers, 52 lighting elements

[0123] 13 feed rollers, 53 light source

[0124] 14-opening roller, 54-camera

[0125] 15 Cleaning Components 55 Lens

[0126] 16 Cleaning components 56 Data cables

[0127] 17 Tooth Tip Circumference 57 Evaluation Unit

[0128] 18-needle cloth 58 shell wall

[0129] 19 suction shield 59 visible section

[0130] 20 suction hoods, 60 evaluation units

[0131] 21 waste branch circuits 61 hinge components

[0132] 22 Waste Sensor Device 62 Locking Device

[0133] 23 sensors, 63 directions

[0134] 24 sensors, starting from 65

[0135] 25 waste pipe 70 steps

[0136] 26. Shell 71-76 Sub-steps

[0137] 27 Shell opening 77 End

[0138] 28 gratings, steps 80, 85, 90

[0139] 29 pressure sensor 91 start

[0140] 30 Inspection Devices 92 Optimized Operation

[0141] 31 Opening Closing Device 93-95 Sub-steps

[0142] 32 separator elements 96 end

[0143] 33 cover elements 100 pretreatment machine

[0144] 34 shell wall 101 channels

[0145] 35 outer side

[0146] 36-frame A direction

[0147] 37. Interior Space E Observation Plane

[0148] 38 camera device F level

[0149] 39 Observation Area T Transportation Direction

[0150] 40 Optical axes: X, Y, Z (longitudinal, transverse, and vertical directions)

Claims

1. A pretreatment machine (1; 100), characterized in that, The pretreatment machine includes a housing (26) that surrounds at least one feed box (2) for fiber material (3) and has at least one housing opening (27) through which the feed box (2) can be seen from the outside; and the pretreatment machine includes at least one inspection device (30) for identifying foreign matter in the fiber material contained in the feed box (2), wherein the inspection device (30) is inserted into the at least one housing opening (27) and includes: - An opening closing device (31) for closing the housing opening (27), wherein the opening closing device (31) has a separating element (32) and a cover element (33) disposed on the separating element (32), the separating element (32) having a transparent viewing area (39) defining a viewing plane (E), wherein an internal space (37) is formed between the separating element (32) and the cover element (33); and - Camera device (38) arranged in the interior space (37). in, - 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 internal space (37) of the opening closing device (31), which deflects the light path (42) originating from the observation area (39) toward the camera device (38).

2. The pretreatment machine (1; 100) 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 pretreatment machine (1; 100) according to claim 1 or 2, characterized in that, The camera device (38) includes at least one line scan camera (54; 54', 54'').

4. The pretreatment machine (1; 100) according to any one of claims 1 to 3, characterized in that, An illumination device (50) for illuminating the fibrous material (3) passing through the observation area (39) is arranged in the interior space (37), wherein the illumination device (50) extends over the entire width of the observation area (39).

5. The pretreatment machine (1; 100) 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) axially spaced from the upper section (45) about 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 pretreatment machine (1; 100) according to claim 5, characterized in that, The cover element (33) is constructed to be opaque in the lower section (46).

7. The pretreatment machine (1; 100) according to claim 5 or 6, characterized in that, The opening closing device (31) has a visible section (59) in which the separating element (32) and the cover element (33) are constructed to be transparent.

8. The pretreatment machine (1; 100) according to any one of claims 1 to 7, characterized in that, The opening closing device (31) has a hinge device (61) for pivotally securing to the pretreatment machine (1; 100) in the area of ​​the housing opening (27).

9. The pretreatment machine (1; 100) according to any one of claims 1 to 8, 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 material level (Fmax) of the at least one cotton feeding box (2), and the at least one inspection device (30) is arranged below the maximum material level (Fmax).

10. The pretreatment machine (1; 100) according to claim 9, characterized in that, A grating (28) or a photoelectric switch is arranged in the at least one cotton feeding box (2), wherein the installation height of the grating (28) or the photoelectric switch specifies the maximum material level (Fmax).

11. The pretreatment machine (1; 100) according to claim 7, characterized in that, The visible section (59) is arranged between the upper section (45) and the lower section (46).

12. An apparatus comprising a plurality of pretreatment machines (1; 100) according to any one of claims 1 to 11.

13. A method for identifying foreign matter in fibrous material (3), said fibrous material being contained in a feed box (2) of a pretreatment machine (1; 100) according to any one of claims 1 to 11 or in a feed box (2) of a device according to claim 12, wherein, The method includes the following steps: - Using the camera device (38) of the corresponding inspection device (30), an image (72) of the fibrous material (3) passing through the observation area (39) is captured; - The content of foreign matter in the fiber material (3) is determined by evaluating the images captured by (73) through at least one evaluation unit (57); - Output (76) at least one output value, the output value including the foreign matter content in the fiber material (3).

14. The method according to claim 13, characterized in that, At least one of the pretreatment machines (1; 100) or the equipment has at least one waste sensor device (22) configured to determine the waste composition of the waste containing foreign matter and good fibers separated from the fibrous material (3) by means of at least one optical sensor (23, 24), and the method includes at least one of the following steps: - Compare at least one output value of (85) with at least one specified and / or previous initial value; - An optimized operation (92) is performed on the textile preparation machine (1; 100) downstream of the corresponding pretreatment machine (1; 100) and / or the textile preparation machine (1; 100) upstream of the corresponding pretreatment machine (1; 100), wherein, when there is a deviation between the at least one output value and the at least one initial value, the position or rotation speed of at least one cleaning element (15, 16) for separating waste from the fiber material (3) is automatically changed, 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).

Images