Bale plucker and method for operating bale plucker

Abstract

The invention relates to a bale plucker (1) for opening a fiber bale (2) placed on a substrate (3), having a machine frame (4) and a height-adjustable gripping unit (5) which is fixed and guided on the machine frame, the gripping unit (5) having a gripping housing (6) and two gripping rollers (7), the grabbing shell is provided with extension parts in the longitudinal direction (X '), the transverse direction (Y') and the vertical direction (Z ') of the shell; the two gripping rollers are arranged in the gripping housing (6) at a distance from each other in the housing longitudinal direction (X ') for gripping fibres from the fibre package, characterized in that a sensor unit (26) is provided for measuring the orientation of the gripping housing (6) in the space, the sensor unit being arranged in a defined position relative to the gripping housing (6) and being in communication connection with a control unit (15), the control unit is configured to trigger an alarm when the orientation of the gripping housing (6) lies outside a predefined tolerance range. The invention further relates to a method for operating a bale plucker.

Description

Technical Field

[0001] The present invention relates to a bag grabbing machine for opening a fiber bag placed on a substrate, the bag grabbing machine having a frame and a height-adjustable grabbing unit fixed and guided on the frame, wherein the grabbing unit has a grabbing housing and two grabbing rollers, the grabbing housing having extensions in the longitudinal direction of the housing, in the transverse direction of the housing, and in the vertical direction of the housing; the two grabbing rollers are arranged in the grabbing housing at intervals from each other in the longitudinal direction of the housing, and are used to grab fibers or fiber bundles from the fiber bag. In addition, the present invention relates to a method for operating the bag grabbing machine. Background Art

[0002] A gripping machine for loosening compressed fiber bales is known from WO 2019 / 211013 A1. The gripping machine comprises a frame that is movable in the direction in which the fiber bales are placed and a gripping unit, which has a gripping housing and two gripping rollers arranged in the gripping housing. The gripping unit is arranged between two side frames of the frame and is suspended on the frame by means of a traction device. The traction device is operatively connected to a drive motor so that the gripping unit can be adjusted in height. Guide rollers are arranged at both ends of the gripping housing, which roll on the guide profiles of the side frames. During on-site assembly by the customer, the gripping unit is hung up and oriented in the target orientation.

[0003] This type of construction has proven to be effective in practice, since it allows high throughputs to be achieved. However, the orientation of the gripping unit can change due to incorrect handling of the gripping machine, constant loads or even after years of normal operation. An inclined gripping unit leads to production technical disadvantages, especially when the gripping unit is tilted in the direction of travel. During the round trip, the corresponding gripping rollers at the front in the direction of travel should act deeper on the fiber package than the gripping rollers arranged behind. If the gripping unit is tilted to the right about its transverse axis perpendicular to the direction of travel, the front gripping roller is too high when the direction of travel is pointing to the left and too low after the change of direction of travel to the right. This can result in different production volumes being cut off when going forward and returning, and the bundle size of the fiber bundles released from the pressed fiber package by the gripping rollers varies greatly. This applies in a similar way to the case where the gripping unit is tilted to the left. Summary of the invention

[0004] The object of the present invention is therefore to eliminate the disadvantages of the prior art and to provide a bale grabber which ensures the most consistent processing of the fiber bundle for a subsequent spinning preparation machine and avoids different production quantities in the round trip. In addition, the object of the present invention is to provide a method which ensures the most consistent processing of the fiber bundle for a subsequent spinning preparation machine and avoids different production quantities in the round trip.

[0005] This object is achieved by a bag gripper of the type mentioned at the outset in that a sensor unit is provided for measuring the orientation of a gripper housing in space, wherein the sensor unit is arranged in a defined position relative to the gripper housing and is communicatively connected to a control unit, wherein the control unit is configured to trigger an alarm when the orientation of the gripper housing is outside a predetermined tolerance range.

[0006] Advantageously, the gripper itself can indicate this or issue a warning if the orientation of the gripper housing is outside a predefined tolerance range, i.e. deviates from a target orientation predefined (especially by the manufacturer) in such a way that the uniformity of the fiber bundle processing and the throughput are negatively affected during continued operation of the gripper. In this way, countermeasures can be taken at an early stage before an incorrect orientation of the gripper housing disrupts the production process of the downstream spinning preparation machine.

[0007] An incorrect orientation of the gripper housing directly affects the positioning of the gripper rollers relative to the fiber package. Thus, the position of the two gripper rollers rotatably mounted on the gripper housing can be inferred by knowing the orientation of the gripper housing. If the gripper housing is incorrectly oriented, the two gripper rollers can be higher or lower than intended, which can cause a significant fluctuation in the processing quality of the fiber bundle during the forward and return round trip of the two gripper rollers to grip the fibers from the fiber package.

[0008] In an advantageous manner, the sensor unit is in particular arranged only on the gripping housing. The defined positions in which the sensor unit and the gripping housing are arranged relative to each other can be clearly predetermined (in particular by the manufacturer). In addition, the sensor unit can be configured to measure the orientation of the gripping housing relative to the plumb line direction. Therefore, the gravitational acceleration (symbol g) in the local direction is used to measure the orientation of the gripping housing in space. By referring to the plumb line direction or a horizontal reference plane perpendicular to this orientation, measurement inaccuracies can be reduced or eliminated, which are caused, for example, by an uneven base at the installation site of the bag grabbing machine. This allows a simple overall determination whether the gripping housing has an inclined position and whether the inclined position is outside a predetermined tolerance range. If the base extends obliquely, one or two correction angles can be stored in the control unit so that the tolerance range is shifted by the corresponding correction angles. In this way, the frame can be erected vertically on a base plane opened by the base.

[0009] The sensor unit, which is fastened to the gripper housing, therefore has the task of detecting the actual orientation of the gripper housing. When the gripper housing is tilted, the direction in which the gravity acts on the sensor unit changes. The control unit receives the measurement signal of the sensor unit and determines the actual orientation of the gripper housing with the aid of the read-out measurement value.

[0010] For example, the gripping housing can be oriented in the target orientation so that the vertical direction of the housing extends parallel to the plumb line direction. In addition, the gripping housing can be oriented in the target orientation so that the plumb line direction is perpendicular to the longitudinal direction of the housing and more preferably perpendicular to the gripping plane spanned by the longitudinal direction of the housing and the transverse direction of the housing. Therefore, the gripping plane can be oriented absolutely horizontally in the target orientation. In the case of an inclination of the substrate, a corresponding correction angle can also be considered relative to the plumb line direction. In particular, a gripping plane parallel to the reference plane is set. Preferably, the transverse direction of the housing, the longitudinal direction of the housing and the vertical direction of the housing define a Cartesian coordinate system assigned to the gripping housing.

[0011] In addition, the sensor unit has at least one sensor module, which is configured to measure the pitch angle between the longitudinal direction of the housing and a horizontal reference plane perpendicular to the plumb line direction. Therefore, an inclined position toward the cutting direction can be detected, wherein the gripping housing is tilted to the left or right or tilted around its longitudinal axis. If the pitch angle is outside the tolerance range, the gripping roller is too low or too high when going forward and returning. In the target orientation, the pitch angle can be 0 degrees or equal to the size of the corresponding correction angle. As an example only, the tolerance range can include a minimum pitch angle of -5 degrees and a maximum pitch angle of +5 degrees. A significantly smaller tolerance range can also be pre-given by the manufacturer, such as + / -2 degrees and even + / -0.5 degrees, so as to always ensure the best cutting characteristics. In particular, in order to measure the pitch angle, the measuring axis of at least one sensor module can be oriented parallel to the longitudinal direction of the housing. The sensor unit can have two of the sensor modules for measuring the pitch angle, and the sensor modules can be arranged at each longitudinal end of the gripping housing spaced apart from each other in the transverse direction of the housing. In this way, a one-sided tilted position of the gripping housing can also be detected if the gripping housing itself is twisted.

[0012] In addition, the sensor unit may have at least one sensor module configured to measure the roll angle between the transverse direction of the housing and one or the horizontal reference plane perpendicular to the plumb line direction. Thus, an inclined position transverse to the cutting direction can be detected, wherein the gripping housing is tilted forward or backward or tilted around its housing transverse axis. In the tilted position, the package array is cut obliquely. In other words, the tilted position of the gripping unit cuts into the package array. Thus, at least on the higher side of the gripping housing, the package array cannot be completely processed to the substrate. In the target orientation, the roll angle can be 0 degrees or equal to the size of the corresponding correction angle. As an example only, the tolerance range can include a minimum roll angle of -5 degrees and a maximum roll angle of +5 degrees. A significantly smaller tolerance range can also be pre-given by the manufacturer, such as + / -2 degrees and even + / -1 degrees, so as to always ensure the best cutting characteristics. In particular, in order to measure the roll angle, the measuring axis of at least one sensor module can be parallel to the transverse direction of the housing.

[0013] The sensor unit may include only one sensor module or multiple sensor modules. If multiple sensor modules are provided, these sensor modules may be of the same type or of different designs. In addition, the measuring axes of at least some of the sensor modules may be oriented identically or differently to each other. However, in principle, all measuring axes may also be oriented identically. The at least one sensor module may be a 1-axis, 2-axis or 3-axis sensor module. If the sensor unit has multiple sensor modules, the measuring axis may be oriented parallel to the longitudinal direction of the housing and / or parallel to the transverse direction of the housing. The sensor unit can thereby measure its orientation with two axes, thereby determining the spatial tilt of the sensor unit or the spatial tilt of the gripping housing relative to the plumb line direction.

[0014] According to a first design solution, the at least one sensor module can be a tilt sensor. As an example only, if high accuracy is required over the entire measuring range, the tilt sensor can be fluid-based, or it can be a MEMS ("micro-electromechanical system")-based tilt sensor, which is particularly low-cost and can be used flexibly. The tilt sensor can also be a mechanical spherical table sensor or an airbag sensor with lower accuracy. If multiple measuring axes are to be covered because pitch and roll angles are to be measured, multiple of the tilt sensors with different orientations can be used. It is also possible to provide at least one multi-axis, in particular biaxial, tilt sensor. In order to compensate for the movements and vibrations generated during the operation of the bag grabber during the tilt measurement, the at least one tilt sensor can also be a combination of two measuring principles. For example, two different types of MEMS sensors can be used, such as an acceleration sensor and a gyroscope.

[0015] According to a second embodiment, as an alternative or in addition to the first embodiment, the at least one sensor module can be an acceleration sensor. Acceleration sensors measure the accelerations acting on them in a manner known per se. Since, in addition to the tilt measurement, vibrations and shocks are also detected, acceleration sensors provide more reliable measurements, in particular when the gripping unit is stationary.

[0016] It also applies to all embodiments that the at least one sensor module can transmit the measurement data to the control unit electronically as a voltage level or via a current interface. Digital transmission is also possible. Each measuring axis of the sensor unit can have an electrical output, which is connected to the control unit. When the orientation of the sensor unit changes, the voltage applied to the corresponding output also changes. For calibration, an initial value of the zero point can be determined for each measuring axis and stored in the control unit. Based on this, the control unit can determine the change relative to the zero orientation or the target orientation and determine the degree of change in the orientation of the gripping housing, in particular, by subtracting the actual value of the measurement from the initial value. If the sensor unit is arranged in a defined position on the gripping housing, calibration is preferably performed in the target orientation.

[0017] In order to measure the orientation of the gripper housing in space, in addition to being arranged on the gripper housing, the sensor unit can also be arranged spaced apart from the gripper housing. For example, the sensor unit can include an optical detection device, such as a camera, a laser system for cross-sectional detection, etc., wherein the detected actual measured values ​​for the current orientation of the gripper housing can be compensated with predetermined (image) data about the target orientation or stored in the control unit. The sensor unit can be arranged in relation to the gripper unit and, for example, on a frame or fixed relative to the base position on a holding structure, such as a base, a column, a building wall or a machine wall, an operating access to a bag gripper or the like.

[0018] Furthermore, the gripping unit can have at least two pressure rollers, to which the gripping plane is arranged tangentially. Preferably, the sensor unit is arranged on a planar housing surface of the gripping housing. In particular, the housing surface or a surface section occupied by the sensor unit is oriented parallel to the gripping plane. Preferably, the plumb line direction is perpendicular to the housing surface in the target orientation, wherein the at least one correction angle can also be taken into account here in the case of an inclined substrate. In a manner suitable for the purpose, the sensor unit is firmly and permanently connected to the gripping housing and can be screwed, riveted, adhesively bonded, etc. to the gripping housing. During the excision, the gripping unit can be placed on the fiber package in the gripping plane.

[0019] Two pressure rollers can be arranged in the longitudinal direction of the housing respectively before and after the gripping roller and can be rotatably mounted on the gripping housing. A possible third pressure roller can be arranged between the gripping rollers and can be rotatably mounted on the gripping housing. The pressure rollers thus ensure that the surface of the fiber pack enters under the gripping unit and can be driven rotationally by means of a drive. When the gripping unit moves past the fiber pack, the surface of the fiber pack is evened out by the respective preceding pressure roller in the cutting direction before the respective preceding gripping roller acts on the surface. Instead of a pressure roller or an additional pressure roller, a guide plate can also be used, which can define the gripping plane with its underside.

[0020] Preferably, the gripping unit has an adjusting device for displacing the gripping rollers relative to one another along the vertical axis of the housing, wherein the control unit is in communication with the adjusting device and is configured to actuate the adjusting device during the forward and return round trip in such a way that the distance of the two gripping rollers that are ahead in the cutting direction from the gripping plane is smaller than the distance of the two gripping rollers that are behind in the cutting direction from the gripping plane. In other words, the gripping rollers can be displaced vertically relative to one another or in the direction of the plumb line in the target orientation of the gripping housing. In the respective round trip, the cutting direction can in particular be changed once, in particular from forward to return.

[0021] The frame is movable back and forth on the base in the longitudinal direction of the machine, along which the fiber packages can be placed. In the case of a movable bale grabber, the cutting direction corresponds to the direction of travel of the bale grabber on the base. A change of direction from forward to return is provided for each round trip, wherein the bale grabber moves, for example, first to the left and then to the right on the bale array, or in the case of a plurality of batches at least only over a partial area of ​​the bale array.

[0022] The bag grabbing machine can have a gantry design. In particular, the frame can have a first side frame and a second side frame and at least one gantry profile connecting the two side frames to each other. The side frames can define a machine vertical axis, which is perpendicular to the base. If the base is flat, the machine vertical axis can correspond to the plumb line direction. The frame can be designed to be movable on the base so that the grabbing unit can be moved above the fiber package. The side frames can have pulleys, wherein the pulleys of the first side frame are guided by rails mounted on the base so that the frame is guided along a particularly straight movement path. The pulleys of the second side frame can slide on the base without further guidance. In order to guide the grabbing unit in a height-adjustable manner, guide elements on the frame side can be arranged on the two side frames, which guide elements cooperate with the guide elements on the grabbing side arranged on the grabbing unit. The guide elements on the frame side can be arranged on the inner sides of the side frames facing each other and can be designed, for example, as guide rails. The guide elements on the frame side can extend parallel to the machine vertical axis. The guide elements on the gripping side can include pulleys which roll on guide rails.

[0023] In addition, the bag gripper has an orientation device for orienting the gripper housing relative to the frame. In this way, the gripper housing can be oriented in particular in the target orientation and, if necessary, a wrong orientation can be corrected in order to prevent the gripper housing from tilting when it is adjusted in height along the guide elements on the frame side. In the target orientation, the machine vertical axis can preferably be perpendicular to the gripper plane. If the base is oblique, the machine vertical axis can be oriented obliquely to the plumb line direction at a corresponding correction angle.

[0024] Preferably, in order to orient the gripping housing around the transverse direction of the housing, that is to say to adjust the pitch angle, the orientation means and the guide means cooperate. For this purpose, at least one pair of the gripping-side guide elements can be arranged adjustably relative to each other in the housing longitudinal direction of the gripping housing on each end side of the gripping unit so as to be able to adjust the distance between the guide elements forming the corresponding pair. For orientation, preferably only one of the two guide elements forming the corresponding pair of guide elements is changed in position relative to the transverse axis of the housing. In this way, the gripping housing can be oriented around its housing transverse axis to adjust the pitch angle. The adjustably constructed guide elements can be eccentrically supported guide rollers that roll on the guide elements on the frame side. The rotation axis of the guide rollers can be oriented parallel to the housing transverse direction of the gripping housing. For example, the orientation means can have eccentric bolts, in particular hexagonal bolts, on which the guide rollers are supported. On each end side of the gripping unit, the guide elements can include a plurality of such guide rollers, which are arranged in pairs with each other and accommodate the guide elements on the frame side between them in pairs. The lowermost pair of guide rollers can be designed to be adjustable for orienting the gripping housing and have, for example, eccentric bearings. The uppermost pair of guide rollers can have bearings that are fixed in position relative to the gripping housing.

[0025] Furthermore, the gripping unit, which is arranged between the two side frames in a height-adjustable manner, can be suspended on the frame by means of traction means. The traction means, for example a belt on which the gripping unit is suspended, can be operatively connected to a drive motor in order to adjust the height of the gripping unit. Preferably, the orientation means and the guide means cooperate in order to orient the gripping housing about the longitudinal direction of the housing. By varying and fixing the length of the traction means, the inclination or the rolling angle of the gripping housing about the transverse axis of the housing can be varied. In particular, the orientation means has a belt lock for each traction means so that the loop formed by the traction means can be adjusted and fixed in width.

[0026] Furthermore, the control unit can be communicatively connected to a display unit in order to visually display the deviation from the tolerance range when the alarm is triggered. To this end, the display unit can include lighting elements arranged, for example, according to a predetermined geometric shape. The shape can be a line having at least one straight segment, an arc segment and / or a curved segment. The lighting unit can be controlled by means of the control unit according to a predetermined lighting scheme in order to present the orientation of the gripping housing. To this end, the lighting scheme can include the lighting elements emitting light in the same or different colors from each other. For example, entering the target orientation can be indicated by means of a green lighting element, and leaving the target orientation can be indicated gradually with yellow, orange and / or red depending on the degree of the wrong orientation. This is particularly advantageous when the sensor unit provides a measurement accuracy, in which, for example, the orientation can be determined with a certain degree of accuracy. At the latest in the case of completely red light, as a further countermeasure, the control unit can stop the bag grabber and / or emit an acoustic warning signal. The warning signal can also be sent to a superior control center, which can include fixed equipment and / or a mobile terminal. In the event of a deviation from the tolerance range, the control unit can warn in an upgraded manner, for example by means of the following stages: (1) activation of an optical warning, (2) activation of an acoustic warning, (3) stopping the bag opening machine. Further or other stages are conceivable and possible. In this way, a person in the vicinity of the bag opening machine can indicate a wrong orientation via a higher-level control device or a mobile terminal from a person who is away from the bag opening machine.

[0027] Another solution to the above-mentioned object is a method for operating the above-mentioned bale opening machine, wherein the sensor unit measures the orientation of the gripper housing in space and transmits the measured values ​​to a control unit, wherein the control unit triggers an alarm when the orientation of the gripper housing is outside a predefined tolerance range. The advantages resulting from the method according to the invention are the same as those described in conjunction with the bale opening machine according to the invention, so that reference is briefly made to the above description here. It goes without saying that all the above-mentioned embodiments of the bale opening machine can be converted into the method and vice versa.

[0028] The gripping unit can be oriented in the target orientation on site during commissioning of the bag grabber, during maintenance or repair work or in similar situations. In order to determine the orientation of the gripping housing based on the measured values ​​of the sensor unit, or to obtain an angle value, the method can have a calibration step before the round trip in time. With the help of the calibration step, the absolute zero value of the sensor unit can be determined to eliminate the so-called zero point error ("zero point offset"). In the calibration step, the gripping housing is preferably in the target orientation. Then, at least one initial measured value that can represent the target orientation is transmitted from the sensor unit to the control unit and stored in the control unit as an initial value. The initial value is selected there. The initial value can thus be used to further determine whether the actual orientation is within the tolerance range or outside the tolerance range.

[0029] Instead of determining the initial value by means of the above-mentioned calibration, a standard value can also be used. The standard value can be stored in the control unit or manually input, for example. For example, the zero value of the sensor unit may have been informed by the manufacturer or measured in a disassembled state, in which the sensor unit is arranged on a horizontal plane for measurement, for example. In this regard, instead of the calibration step or if necessary, the method can also additionally include an initial step, in which at least an initial value representing the target orientation stored in the control unit is selected.

[0030] Furthermore, the tolerance range can be measured. For this purpose, the gripping housing can be deflected up to a limit value and the corresponding measurement signal of the sensor unit can be stored in the control unit. Alternatively or additionally, the tolerance range can be stored in the control unit or input manually. In this case, possible correction angles due to a skewed substrate can be taken into account.

[0031] During the round trip and / or in time after the round trip, the method may further comprise at least one checking step in which the sensor unit transmits at least one actual measured value representing the current orientation of the gripping housing ("actual orientation") to the control unit, wherein the control unit checks whether the actual measured value is outside the tolerance range by means of the at least one selected initial value. Preferably, the checking step is performed when the bag grabber is stopped, for example during the placement of the bag array. In particular, during the checking step, the frame is always in the same position of its movement path. For example, the frame can be at one of the two end points of the movement path or at one of the two inflection points or at the midpoint. In particular, during the checking step, the frame is in the same position as when the calibration was performed. If the checking step is performed during the round trip, a delay, for example a delay of 1 minute, can be stored by the control unit when determining a wrong orientation, during which delay it is checked whether the wrong orientation still exists. In this way, a short-term wrong orientation due to local substrate unevenness does not trigger a warning. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Further features and advantages of the invention emerge from the following description of preferred embodiments.

[0033] In the figure:

[0034] Figure 1 A perspective view of a bag opening machine according to one embodiment of the invention is shown, wherein a gripping unit of the bag opening machine is oriented in a target orientation and a bag array is placed on a placement surface of the bag opening machine;

[0035] Figure 2 Show Figure 1 Another perspective view of the bag grabber in FIG. 1, wherein the front side frame without the entrance door is shown;

[0036] Figure 3 Show Figure 1 A schematically simplified cross-sectional view of a gripping unit of a bag gripping machine in which the gripping unit is oriented in a target orientation and the gripping rollers of the gripping unit are set to a travel direction to the left;

[0037] Figure 4 Show Figure 3 a gripping unit oriented in a target orientation, wherein the gripping roller is set to a right-hand travel direction;

[0038] Figure 5 Show Figure 3 A gripping unit in which the gripping unit is misoriented or tilted about a transverse axis of the housing and the gripping rollers are set in a left-hand direction of travel;

[0039] Figure 6 Show Figure 5 An incorrectly oriented gripping unit in the embodiment of the present invention, wherein the gripping rollers are set to a right-hand travel direction;

[0040] Figure 7 Show Figure 1 A schematically simplified side view of a bag grabber in which the grab unit is misoriented or tilted about the longitudinal axis of the housing;

[0041] Figure 8 Show Figure 1 An end side view of a grabbing unit of a bag grabbing machine; and

[0042] Fig. 9 Show Figure 1 A perspective detail view of a bale gripper in FIG. 1 , wherein the gripping unit is shown without the housing cover. DETAILED DESCRIPTION

[0043] exist Figure 1 to Figure 2 , a spinning preparation machine according to one embodiment of the invention is shown, which is designed as a bale grabbing machine 1. The bale grabbing machine 1 is used in a known manner to open compressed fiber packages 2, in particular fiber packages consisting of cotton, torn fibers, etc., which are placed side by side in a plurality of rows on a base 3 along the longitudinal direction X of the machine. The bale grabbing machine 1 has a frame 4, which can be moved on the base 3 along the longitudinal direction X of the machine. A gripping unit 5 is fixed and guided on the frame 4, which can be adjusted in height along the vertical axis Z of the machine. The gripping unit 5 has a gripping housing 6 which is open downwards, i.e. towards the base 3, in which two drivable gripping rollers 7 are arranged for gripping fiber bundles from the surface of the fiber package 2.

[0044] exist Figure 1 , Figure 2 and Figure 7In order to clarify the orientation of the bag grabber 1 in space, the machine longitudinal direction X, the machine transverse direction Y and the machine vertical direction Z are indicated, which are defined in a spatially fixed Cartesian coordinate system and are represented by corresponding arrows. Assuming that the base 3 is oriented absolutely horizontally, the machine vertical axis Z extends parallel to the plumb line direction L. The base 3 is then located in a horizontal reference plane H, and the plumb line direction L is perpendicular to this reference plane. However, the base 3 in the installed position is usually not flat, so that the plumb line direction L or the reference plane H perpendicular to this orientation is taken into account for the orientation of the grabber housing 6, rather than the base 3.

[0045] In addition, Figures 3 to 7 In order to clarify the orientation of the gripping housing 6 in space, a housing longitudinal direction X′, a housing transverse direction Y′ and a housing vertical direction Z′ are indicated, which are assigned to a Cartesian coordinate system fixed to the body of the gripping housing 6 and are indicated by corresponding arrows.

[0046] The frame 4 comprises a front frame 9 at the front side 8 of the bag grabber 1 and a rear frame 11 at the rear side 10 of the bag grabber 1. Pulleys 12 are arranged on the rear frame 11, which roll on rails 13 mounted on the base 3 in order to guide the frame 4 in the longitudinal direction X of the machine. Further pulleys 14 are arranged below the front frame 9, which roll directly on the base 3 when the frame 4 moves back and forth.

[0047] The bag grabbing machine 1 has an electrical control unit 15 for monitoring and controlling the movement functions, sensor mechanisms and actuating mechanisms of the bag grabbing machine 1. Figure 2 The front frame 9 is shown without an access door, thereby exposing the control unit 15. Manual control of the bag grabber 1 can be performed via a control console 16, which is mounted outside the movement path of the frame 4. The operator can access the electrical control unit 15 via the control console 16 and possibly also via an optional input-output interface (not shown) arranged on the front frame 9.

[0048] Between the two side frames 9, 11 extend two gantry profiles 17, 18 arranged at a distance from each other, which rigidly connect the two side frames 9, 11 to each other. The gripping unit 5 is suspended on the frame 4 in a known manner by means of two traction means 19 arranged at a distance from each other, wherein the traction means 19 is coupled to a drive to adjust the height of the gripping unit 5. Such a suspension is described in WO 2019 / 211013A1, with reference in particular to the description of the operating principle on page 9, line 25 to page 12, line 4 and the figures mentioned therein.

[0049] According to Figure 28, the frame 4 moves the gripper unit 5 first forward (here to the left) during a round trip and after a change of direction back (here to the right). The forward direction is indicated by arrow A and the return direction is indicated by arrow B. After each round trip, the height-adjustable gripper unit 5 can be lowered further by one feed amount.

[0050] The gripping housing 6 has extensions in the longitudinal direction X' of the housing, the transverse direction Y' of the housing and the vertical direction Z' of the housing. The gripping housing 6 has a basic shape of a box that is open downward. The extension of the gripping housing in the transverse direction Y' of the housing can be more than twice the extension in the longitudinal direction X' of the housing. Preferably, the ratio is between 2.3 to 1 and 3.5 to 1. The rotatably driven drive roller 7 is rotatably supported in the gripping housing 6 and is arranged spaced apart from each other in the longitudinal direction X' of the housing. The fiber bundles peeled off from the gripping roller 7 are sucked away in a known manner by a suction device 25 arranged above the gripping roller 7 and conveyed to their next application through a transport channel 20. The transport channel 20 extends along the rear side 10 of the bag grabbing machine 1 outside the placement surface of the bag array.

[0051] In the housing longitudinal direction X' in front of and between the gripping rollers 7, three pressure rollers 21 are rotatably supported in parallel axes on the gripping housing 6. The pressure rollers 21 press onto the surface of the fiber pack 2 and ensure that the surface of the fiber pack 2 enters under the gripping unit 5. A gripping plane E is defined below the pressure rollers 21, which is arranged tangentially to the pressure rollers 7 and is oriented parallel to the housing longitudinal direction X' and the housing transverse direction Y'.

[0052] The gripping unit 5 has a coupling switch which is realized by means of an adjusting device 22 in order to displace the gripping rollers 7 relative to each other and parallel to the housing vertical direction Z' within the gripping housing 6. Figure 8 , a front side view of the front frame 9 is shown. The adjusting device 22 comprises a pivot lever 24 pivotable about a central rotation point 23 at each end side. For the pivoting, an actuator (not shown) acts on the pivot lever 24 at the end side of the rear frame 11. The actuator is in communication with a control unit 15. The control unit 15 is configured to control the actuator during the respective round trip in such a way that the distance between the gripping plane E of the gripping roller 7' which is respectively ahead of the two gripping rollers 7 in the direction of travel is smaller than the distance between the gripping plane E of the gripping roller 7" which is respectively behind the two gripping rollers 7 in the direction of travel. In this way, the current consumption of the two gripping rollers 7', 7" is always as equal as possible.

[0053] according to Figure 3 , the gripping unit 5 moves to the left and is (here by way of example) in the forward direction A. Accordingly, the gripping roller 7' at the front left side penetrates deeper into the fiber package 2 than the gripping roller 7" at the rear right side. Figure 4 , the gripping unit 5 is moved to the right and is in (here by way of example) return B, wherein the right gripping roller 7" now engages deeper into the fiber package than the following left gripping roller 7'.

[0054] In order to achieve the greatest possible throughput and the most uniform possible bundle processing, the gripper housing 6 is arranged or fixed in a defined, ie predetermined, target orientation in space, such as Figures 1 to 4 As shown in . In the target orientation, the pitch angle α (here) formed between the plumb line direction L and the longitudinal axis X' of the housing is 0 degrees. In addition, in the target orientation, the roll angle β (here) formed between the plumb line direction L and the transverse direction Y' of the housing is 0 degrees. However, due to events during the operation of the bag grabbing machine 1, the grabbing housing 6 may be tilted about the longitudinal axis X' of the housing and / or the transverse axis Y' of the housing. In the event of a tilt of the substrate 3 (which may be perpendicular to the vertical axis X of the machine), the pitch angle α or the roll angle β in the target orientation is equal to the corresponding correction angle to compensate for the inclination of the substrate 3.

[0055] exist Figure 5 and Figure 6 In FIG. 6 , the gripping housing 6 is tilted to the right about the housing transverse axis Y′, so that the pitch angle α (here, for example) is +2 degrees. Figure 5 It can be seen that in the left-pointing travel direction (towards A), the heights of the two gripping rollers 7 ', 7 "are equal and the engagement switching is almost eliminated. Figure 6 After the change of direction (return B), in addition to the vertical displacement due to the engagement switch, the front gripper roller 7" to the right is now located deeper in the material of the fiber package 2 at the level or pitch angle α in an inclined position and handles the package surface unevenly.

[0056] according to Figure 8 , the gripping housing 6 is tilted clockwise or backwards about the housing longitudinal axis X', so that the rolling angle β (here, for example) is +2 degrees. This tilted position enters the bag array as an inclined surface.

[0057] For measuring the actual orientation, a sensor unit 26 is provided, which is arranged in a defined position with respect to the gripping housing 6. The sensor unit 26 is communicatively connected to the control unit 15, wherein the control unit 15 is configured to trigger an alarm when the actual orientation of the gripping housing 6 is outside a predefined tolerance range. The control unit 15 is also connected to a display unit, which can emit an optical alarm in the event of a wrong orientation. For example, the display unit can have a light-emitting diode bar 27, which is arranged on the machine housing of the frame 4 and further preferably on the machine housing of the gantry profiles 17, 18 so as to be well visible from the outside on both sides. The display unit can also include a display 28 of the control console 16. In addition, the display unit can also include a mobile terminal (not shown).

[0058] The sensor unit 26 has at least one sensor module 29 , 30 , which can be an inclination sensor or an acceleration sensor. Both sensor types are suitable in principle for measuring the orientation of the gripping housing 6 relative to the vertical direction L.

[0059] In the embodiment shown, the sensor unit 26 comprises two such sensor modules 29, 30, which are spaced apart from each other along the housing transverse axis Y' and are arranged at each of the two ends of the gripping housing 6. Each sensor module 29, 30 is designed to be biaxial, that is, it has two measuring axes. Each first of the two measuring axes measures the pitch angle α between the housing longitudinal direction X' and the horizontal reference plane H (the plumb line direction L is perpendicular to it), and each second of the two measuring axes measures the roll angle β between the housing transverse direction Y' and the horizontal reference plane H.

[0060] Furthermore, the sensor unit 26 is arranged on the inside on a housing wall 31 of the gripping housing 6, so that the sensor modules 29, 30 are located on the inside. Figure 1 and Figure 2 31 is indicated by means of dashed lines in FIG. As shown here, the housing wall 31 can be an upper housing wall, i.e., a cover of the gripping housing 6. Preferably, the housing wall 31 is designed to be flat where the sensor unit 26 is fastened and is oriented parallel to the gripping plane E. The sensor unit 26 can be fastened to the gripping housing 6 by means of screws, rivets, adhesive or the like in order to firmly define a defined position on the gripping housing 6.

[0061] A target orientation is stored in the control unit 15 and can be predetermined by the manufacturer. In the target orientation, the gripping housing 6 (here for example) can be oriented with a housing longitudinal direction X′ and a housing transverse direction Y′, each parallel to a horizontal reference plane H. Preferably, the housing wall 31 or the region of the housing wall 31 occupied by the control unit 15 is oriented parallel to the horizontal reference plane H in the target orientation. Target orientations other than the horizontal target orientation are also possible, in particular when correction angles are to be taken into account due to an inclined substrate 3.

[0062] A tolerance range can be predefined in the control unit 15, within which deviations from the target orientation are tolerable. For example, the tolerance range can include a pitch angle range of + / -5 degrees and a roll angle range of + / -10 degrees. The target orientation or zero position may, but does not have to, be at the midpoint of the tolerance range. In principle, it is also conceivable that a tilt position in one direction is tolerable to a greater extent than in another direction. Taking the pitch angle α as an example, the tolerance range can include a range from a minimum pitch angle α of -7 degrees to a maximum pitch angle α of +5 degrees. The pitch angle range and the roll angle range may also influence each other. The gripping housing 6 is so misoriented outside the tolerance range that the control unit 15 triggers an alarm.

[0063] In order to orient the gripper housing 6 in a target orientation or to correct an incorrect orientation, the bale gripper 1 has an orientation means 32 which cooperates (here for example) with the traction means 19 for height adjustment and with the guide means 33 of the bale gripper 1, see Figure 8 and Fig. 9 .

[0064] Specifically, the gripping unit 5 suspended between the two side frames 9, 11 is guided on the two side frames 9, 11. In order to guide the height-adjustable gripping housing 6, frame-side guide elements are arranged on the two side frames 9, 11. Here, these guide elements include vertically oriented guide profiles 34, which are arranged on the inner sides of the side frames 9, 11 facing each other and protrude into the intermediate space formed between the two side frames 9, 11. The guide profiles 34 can be designed, for example, as guide rails, which can be fastened to the corresponding side frames 9, 11 by means of a one-piece construction with the corresponding side frame or, for example, by means of a screw connection.

[0065] Furthermore, a gripping-side guide element 35 is arranged on each end side of the gripping housing 6, which is supported on the guide profile 34. The gripping-side guide element 35 is explained in detail below using one of the two end sides as an example, wherein the structure on both end sides can be the same. Four guide rollers 36, 37, 38, 39 and a support roller 40 are arranged on each end side, which are rotatably supported on the gripping housing 6. The rotation axis of the guide rollers 36, 37, 38, 39 is oriented parallel to the housing transverse direction Y' and the rotation axis of the support roller 40 is oriented parallel to the housing longitudinal direction X'. The guide rollers 36, 37, 38, 39 are allocated in pairs and form an upper pair of rollers 36, 37 and a lower pair of rollers 38, 39. The guide profile 34 of the corresponding side frame 9, 11 is sandwiched between the respective roller pairs of the guide rollers 36, 37, 38, 39. When the gripping housing 6 is raised and lowered, the guide rollers 36, 37, 38, 39 roll on the flanks of the guide profile 34. The support roller 40 is located between the gripping housing 6 and the guide profile 34 and rolls on the central beam of the guide profile 34 pointing toward the gripping housing 6.

[0066] In order to orient the gripping housing 6 about the housing transverse axis Y', i.e., to correct the pitch angle α, the orientation means 32 has two eccentric bolts 41, 42, in particular hexagonal bolts, on which the two guide rollers 38, 39 of the lower roller pair are rotatably supported. The upper pair of guide rollers 36, 37 are supported on the gripping housing 6 in a fixed position relative thereto. For example, if the lower pair of guide rollers 38, 39 is shifted to the left by rotating the two bolts 41, 42, as seen from the front side 8 of the bag grabbing machine 1 to the rear side frame 11, the gripping housing 6 is rotated clockwise about the housing transverse direction Y'. In this way, a negative pitch angle α can be corrected. In a similar manner, a positive pitch angle α can be corrected by rotating the two bolts 41, 42 in the opposite direction. The gripping housing 6 can be adjusted about the housing transverse axis Y' until the pitch angle α is at least approximately 0 degrees or is equal to the corresponding correction angle.

[0067] In order to orient the grip housing 6 about the housing longitudinal axis X', i.e. to correct the roll angle β, the orientation means 32 has a fixing means 43 in order to be able to adjust and fix the length of the two traction means 19, on which the two ends of the grip housing 6 are suspended. Specifically, the fixing means 43 is a belt buckle in order to be able to adjust and fix the loop formed by the traction means 19 in terms of width. The respective traction means 19 can be extended or shortened until the roll angle β is at least approximately 0 degrees or equal to the respective correction angle.

[0068] In order to calibrate the sensor unit 26 during commissioning of the gripper 1, the gripper housing 6 of the suspended gripper unit 5 is first transferred into the target orientation. In order to measure the pitch angle α, a conventional spirit level can be placed on the outside of the housing wall 31. For this purpose, the measuring axis of the spirit level is oriented parallel to the longitudinal direction of the housing. In order to measure the roll angle β, a tape measure can be used in order to determine the distance to the portal profiles 17, 18 arranged above the gripper unit 5 at both ends of the gripper housing 6. After the gripper housing 6 has been oriented in the target orientation (here: pitch angle α=0 degrees and roll angle β=0 degrees), the measured values ​​transmitted by the sensor unit 26 to the control unit 15 can be stored in the control unit 15 as initial values ​​or "zero" values. During the operation of the gripper 1, the initial values ​​are used to determine whether the actual orientation detected is within or outside the tolerance range. In addition to determining the initial values ​​by means of the above-described calibration method, standard values ​​stored in the control unit 15 by the manufacturer can also be used.

[0069] The tolerance range can be stored in the control unit 15 or input manually. However, it can also be measured. For this purpose, the gripping housing 6 can be deflected up to the limit values, i.e. the minimum and maximum pitch angle α and the minimum and maximum roll angle β, and the measured values ​​transmitted by the sensor unit 26 are stored in the control unit 15. The voltage values ​​or current values ​​up to the corresponding limit values ​​form the permissible measured value range.

[0070] During the round trip of the bag grabber 1 and / or after the round trip in time, the control unit 15 checks whether the measured value transmitted by the sensor unit 26 is within the permissible value range. If the measured value deviates from the permissible value range, this indicates that the current orientation ("actual orientation") of the gripper housing 6 is outside the tolerance range. The control unit 15 then triggers an alarm. If the actual orientation is within the tolerance range, no warning is triggered.

[0071] The invention is not limited in its implementation to the preferred exemplary embodiments given above. Rather, many variants are conceivable which also use the described solution in principle in different types of embodiments. All features and / or advantages resulting from the claims, the description or the drawings, including structural details or spatial arrangements, may be essential to the invention both per se and in different combinations.

[0072] List of reference numerals:

[0073] 1 Bag grabber 36 guide roller

[0074] 2 Fiber Pack 37 Guide Rollers

[0075] 3 base 38 guide roller

[0076] 4 racks 39 guide rollers

[0077] 5 Grasping unit 40 Support roller

[0078] 6 Grab the housing 41 bolts

[0079] 7 Grab Roller 42 Bolt

[0080] 8 front side 43 fixing device

[0081] 9 side frames

[0082] 10 Rear

[0083] 11 side frame

[0084] 12 pulleys

[0085] 13 Slide rail α pitch angle

[0086] 14 Pulley β rolling angle

[0087] 15Control Unit A Go to

[0088] 16 Console B returns

[0089] 17 Gantry profile E grabbing plane

[0090] 18H datum plane of mast profile

[0091] 19 Plumb line direction of traction device L

[0092] 20 transport channels x machine longitudinal direction

[0093] 21 Pressure roller Y machine transverse direction

[0094] 22 Adjustment device Z machine vertical direction

[0095] 23 Rotation point X' Shell longitudinal direction

[0096] 24 Swing rod Y' shell lateral direction

[0097] 25 Suction device Z' shell vertical direction

[0098] 26Control Unit

[0099] 27LED Strip

[0100] 28 Displays

[0101] 29 sensor modules

[0102] 30 sensor modules

[0103] 31 Shell wall

[0104] 32 Directional Devices

[0105] 33 Boot Device

[0106] 34 Guide Profiles

[0107] 35 Guiding elements

Claims

1. A bag grabbing machine (1) for opening a fiber bag (2) placed on a substrate (3), the bag grabbing machine having a frame (4) and a height-adjustable gripping unit (5) fixed and guided on the frame, wherein: The gripping unit (5) comprises a gripping shell (6) and two gripping rollers (7), wherein the gripping shell has an extension along the longitudinal direction (X') of the shell, the transverse direction (Y') of the shell and the vertical direction (Z') of the shell; the two gripping rollers are arranged in the gripping shell (6) along the longitudinal direction (X') of the shell and are spaced apart from each other for gripping fibers from a fiber package, and is characterized in that a sensor unit (26) is provided for measuring the orientation of the gripping shell (6) in space, wherein the sensor unit (26) is arranged in a position defined relative to the gripping shell (6) and is communicatively connected to a control unit (15), wherein the control unit (15) is configured to trigger an alarm when the orientation of the gripping shell (6) is outside a predetermined tolerance range.

2. The bag grabbing machine (1) according to claim 1, characterized in that: The sensor unit (26) is arranged on the gripping housing (6) and is configured to measure the orientation of the gripping housing (6) relative to a plumb line direction (L).

3. The bag grabbing machine (1) according to claim 2, characterized in that: The sensor unit (26) has at least one sensor module (29, 30) configured to measure a pitch angle (α) between a longitudinal direction (X') of the housing and a horizontal reference plane (H) perpendicular to a plumb line direction (L).

4. The bag grabbing machine (1) according to claim 3, characterized in that: The sensor unit (26) has at least two sensor modules (29, 30) configured to measure a pitch angle (α), the sensor modules being arranged at intervals from each other in a housing transverse direction (Y') and respectively on one end of the gripping housing (6).

5. The bag grabbing machine (1) according to any one of claims 2 to 4, characterized in that: The sensor unit (26) has at least one sensor module (29, 30) which is configured to measure a roll angle (β) between a housing transverse direction (Y') and a horizontal reference plane (H) perpendicular to the plumb line direction (L) or the horizontal reference plane (H).

6. The bag grabbing machine (1) according to any one of claims 3 to 5, characterized in that: The at least one sensor module (29, 30) is a tilt sensor or an acceleration sensor.

7. The bag grabbing machine (1) according to any one of claims 1 to 6, characterized in that: The gripping unit (5) has at least two pressure rollers (21), wherein a gripping plane (E) oriented parallel to the longitudinal direction (X') of the housing and the transverse direction (Y') of the housing is arranged tangentially to the pressure rollers (21).

8. The bag grabbing machine (1) according to claim 7, characterized in that: The gripping unit (5) has an adjusting device (22) for displacing the gripping rollers (7) relative to each other parallel to the vertical direction (Z') of the shell, wherein the control unit (15) is communicatively connected to the adjusting device (22) and is configured to control the adjusting device (22) during a round trip of the two gripping rollers (7) gripping fibers from the fiber package (2) in such a way that the distance between the gripping roller (7'; 7") ahead of the two gripping rollers (7) in the cutting direction (A, B) and the gripping plane (E) is smaller than the distance between the gripping roller (7"; 7') behind the two gripping rollers (7) in the cutting direction (A, B) and the gripping plane (E).

9. The bag grabbing machine (1) according to any one of claims 1 to 8, characterized in that: The bag grabbing machine (1) has an orientation device (32) for orienting the grabbing housing (6) relative to the machine frame (4).

10. The bag grabbing machine (1) according to any one of claims 1 to 9, characterized in that: The frame (4) comprises a first side frame (9) and a second side frame (11) and at least one portal profile (17, 18) connecting the two side frames (9, 11) to each other, wherein, in order to guide the gripping unit (5) in a height-adjustable manner, frame-side guide elements (34) are arranged on the two side frames (9, 11), and the frame-side guide elements cooperate with gripping-side guide elements (35) arranged on the gripping unit (5).

11. The bag grabbing machine (1) according to claim 10, characterized in that: The gripper-side guide element (35) comprises eccentrically mounted guide rollers (38, 39) which roll on the frame-side guide element (34).

12. The bag grabbing machine (1) according to any one of claims 1 to 11, characterized in that: The control unit (15) is communicatively connected to a display unit (27, 28), wherein the display unit (27, 28) visually displays a deviation from a tolerance range when an alarm is triggered.

13. Method for operating a bale opening machine according to any one of claims 1 to 12, characterized in that The sensor unit (26) measures the orientation of the gripping housing (6) in space and transmits the measured values ​​to a control unit (15), wherein the control unit (15) triggers an alarm if the orientation of the gripping housing (6) is outside a predefined tolerance range.

14. The method according to claim 13, characterized in that Prior to the round trip of the two gripping rollers for gripping the fibers from the fiber package (2), the method comprises either a calibration step or an initialization step, in which the gripping housing (6) is in a target orientation and at least one initial measurement value is transmitted by the sensor unit (26) to the control unit (15) and is stored and selected in the control unit (15) as an initial value; in the initialization step, at least one initial value representing the target orientation stored in the control unit (15) is selected.

15. The method according to claim 14, characterized in that The method comprises at least one checking step during and / or in time after the round trip, in which the sensor unit (26) transmits at least one actual measured value representing the current orientation of the gripping shell (6) to a control unit (15), wherein the control unit (15) checks with the aid of the selected at least one initial value whether the actual measured value is outside a tolerance range.

Images