Grabbing machine and method for operating a grabbing machine

Abstract

The invention relates to a bale plucker (1) for opening up bales (2) of fibers placed on a base (3), having a frame (4) and a height-adjustable plucking unit (5) fixed and guided on the frame, wherein the plucking unit (5) has a plucking housing (6) and two plucking rollers (7), the plucking housing having an extension in a housing longitudinal direction (X'), a housing transverse direction (Y') and a housing vertical direction (Z'); the two plucking rollers are arranged in the plucking housing (6) spaced apart from one another in the housing longitudinal direction (X') for plucking fibers from the bales, characterized in that a sensor unit (26) is provided for measuring the orientation of the plucking housing (6) in space, wherein the sensor unit is arranged in a position defined relative to the plucking housing (6) and is in communication connection with a control unit (15), wherein the control unit is configured to trigger an alarm when the orientation of the plucking housing (6) is outside a pre-defined tolerance range. Furthermore, the invention relates to a method for operating a bale plucker.

Description

Technical Field

[0001] This invention relates to a bale-grabbing machine for opening fiber bales placed on a substrate. The bale-grabbing machine has a frame and a height-adjustable gripping unit fixed and guided on the frame. The gripping unit has a gripping housing and two gripping rollers. The gripping housing has extensions along its longitudinal direction, its transverse direction, and its vertical direction. The two gripping rollers are arranged spaced apart from each other in the gripping housing along its longitudinal direction for gripping fibers or fiber bundles from the fiber bales. Furthermore, this invention relates to a method for operating the bale-grabbing machine. Background Technology

[0002] A bale-grabbing machine for opening and loosening compressed fiber bales is known from WO 2019 / 211013 A1. The bale-grabbing machine includes a frame movable along the placement direction of the fiber bales and a gripping unit having a gripping housing and two gripping rollers arranged within the gripping housing. The gripping unit is arranged between two side frames of the frame and suspended from the frame by means of a traction device. The traction device is operatively connected to a drive motor to allow for height adjustment of the gripping unit. Guide rollers are arranged at both ends of the gripping housing, and these guide rollers roll on guide profiles of the side frames. During on-site customer assembly, the gripping unit is hung and oriented in a target orientation.

[0003] This structural approach has proven effective in practice because it allows for high production volumes. However, the orientation of the gripping unit can change due to improper handling of the gripper, continuous load, or even after years of normal operation. Tilted gripping units introduce production disadvantages, particularly when the gripping unit is tilted in the travel direction. During the round trip, the corresponding gripping roller at the front in the travel direction should act on the fiber bale more deeply than the gripping roller positioned behind it. If the gripping unit tilts to the right about its transverse axis perpendicular to the travel direction, the front gripping roller will be too high when the travel direction is pointing to the left and too low after changing direction to the right. This can result in different yields on the forward and return trips, and significant variations in the bundle size of the fiber bundles released from the compressed fiber bale by the gripping rollers. A similar situation applies when the gripping unit is tilted to the left. Summary of the Invention

[0004] The object of the present invention is therefore to overcome the disadvantages of the prior art and to provide a bag-grabbing machine that ensures as consistent a treatment of fiber bundles as possible for subsequent spinning preparation machines and avoids different production volumes in the round trip. Furthermore, the object of the present invention is to provide a method that ensures as consistent a treatment of fiber bundles as possible for subsequent spinning preparation machines and avoids different production volumes in the round trip.

[0005] This task is accomplished using a grabber of the type mentioned at the beginning, in the following manner: a sensor unit is set up to measure the orientation of the grabbing housing in space, wherein the sensor unit is arranged in a position defined relative to the grabbing housing and is communicatively connected to a control unit, wherein the control unit is configured to trigger an alarm when the orientation of the grabbing housing is outside a pre-given tolerance range.

[0006] Advantageously, if the orientation of the gripper housing is outside the pre-defined tolerance range—that is, if such a deviation (especially by the manufacturer) from the pre-defined target orientation negatively impacts the uniformity of fiber bundle processing and production output during continued operation of the gripper—the gripper itself can identify this or issue a warning. In this way, countermeasures can be taken early before the incorrect orientation of the gripper housing interferes with the production process of downstream spinning preparation machines.

[0007] Incorrect orientation of the gripping housing directly affects the positioning of the gripping rollers relative to the fiber bundle. Therefore, by understanding the orientation of the gripping housing, the positions of the two gripping rollers rotatably supported on the gripping housing can be deduced. If the gripping housing is incorrectly oriented, the two gripping rollers may be higher or lower than intended, resulting in significant fluctuations in the processing quality of the fiber bundle during the forward and return strokes of the two gripping rollers as they grip the fibers from the fiber bundle.

[0008] Advantageously, the sensor unit is arranged solely on the gripping housing. The defined positions of the sensor unit and the gripping housing relative to each other can be explicitly predetermined (particularly by the manufacturer). Furthermore, the sensor unit can be configured to measure the orientation of the gripping housing relative to a vertical direction. Thus, the local direction of gravitational acceleration (symbol g) is used to measure the orientation of the gripping housing in space. Measurement inaccuracies, such as those arising from an uneven base at the placement site of the gripper, can be reduced or eliminated by referencing a vertical direction or a horizontal reference plane perpendicular to this orientation. This allows for a generally simple determination of whether the gripping housing has a tilted position and whether said tilted position is outside a predetermined tolerance range. If the base extends tilted, one or two correction angles can be stored in the control unit so that the tolerance range is moved by the corresponding correction angle. In this way, the frame can be erected vertically on a base plane opened by the base.

[0009] Therefore, secured to the gripping housing, the sensor unit has the task of detecting the actual orientation of the gripping housing. When the gripping housing is tilted, the direction of gravity acting on the sensor unit changes. The control unit receives the measurement signal from the sensor unit and determines the actual orientation of the gripping housing by means of the read measurement value.

[0010] For example, in target orientation, the gripping housing can be oriented such that the vertical direction of the housing extends parallel to the plumb line. Furthermore, the gripping housing can be oriented in target orientation such that the plumb line is perpendicular to the longitudinal direction of the housing, and more preferably perpendicular to the gripping plane that is formed by the longitudinal and transverse directions of the housing. Therefore, the gripping plane can be absolutely horizontally oriented in target orientation. In the case of a tilted base, a corresponding correction angle can also be considered relative to the plumb line. In particular, a gripping plane parallel to a reference plane is provided. Preferably, the transverse, longitudinal, and vertical directions of the housing define a Cartesian coordinate system assigned to the gripping housing.

[0011] Furthermore, the sensor unit has at least one sensor module configured to measure the pitch angle between the longitudinal direction of the housing and a horizontal reference plane perpendicular to the vertical direction. Therefore, a tilt position towards the cutting direction can be detected, where the gripping housing tilts to the left or right or about its longitudinal axis. If the pitch angle is outside the tolerance range, the gripping roller is too low or too high during forward and return movements. 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-defined by the manufacturer, such as + / -2 degrees and even possibly + / -0.5 degrees, to always ensure optimal cutting characteristics. Specifically for measuring 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 may have two of the sensor modules for measuring the pitch angle, which can be arranged spaced apart from each other at each longitudinal end of the gripping housing along the lateral direction of the housing. In this way, if the gripping housing itself twists, the tilt position of one side of the gripping housing can also be detected.

[0012] Furthermore, the sensor unit may have at least one sensor module configured to measure the roll angle between the housing's lateral direction and one of the horizontal reference planes perpendicular to the vertical direction. Thus, a tilted position transverse to the cutting direction can be detected, where the gripping housing tilts forward or backward or about its lateral axis. In this tilted position, the package array is cut at an angle. In other words, the tilted position of the gripping unit cuts into the package array. Consequently, at least on the higher side of the gripping housing, the package array cannot be completely processed to the substrate. In target orientation, the roll angle can be 0 degrees or equal to the size of the corresponding correction angle. By way of example only, the tolerance range may include a minimum roll angle of -5 degrees and a maximum roll angle of +5 degrees. A significantly smaller tolerance range, such as + / -2 degrees and even possibly + / -1 degree, may also be pre-defined by the manufacturer to always ensure optimal cutting characteristics. In particular, for measuring the roll angle, the measuring axis of at least one sensor module may be parallel to the housing's lateral direction.

[0013] The sensor unit may include only one or more of the sensor modules. If multiple sensor modules are provided, these sensor modules may be of the same type or different designs. Furthermore, the measurement axes of at least some of the sensor modules may be oriented the same or different from each other. However, in principle, all measurement axes may also be oriented the same. 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 measurement axes may be oriented parallel to the longitudinal direction of the housing and / or parallel to the transverse direction of the housing. Thus, the sensor unit can measure its orientation along two axes, thereby determining the spatial tilt of the sensor unit or the spatial tilt of the gripping housing relative to the vertical direction.

[0014] According to the first design, the at least one sensor module can be a tilt sensor. By way of example only, if high accuracy is required across the entire measurement range, the tilt sensor can be fluid-based, or it can be a MEMS (“Micro-Electro-Mechanical Systems”) tilt sensor, which is particularly low-cost and flexible. The tilt sensor can also be a mechanical spherical stage sensor or a pneumatic sensor with lower accuracy. If multiple measurement axes need to be covered because pitch and roll angles need to be measured, multiple tilt sensors with different orientations can be used. It is also possible to provide at least one multi-axis, especially a dual-axis, tilt sensor. To compensate for motion and vibration generated during the operation of the grabber during tilt measurement, the at least one tilt sensor can also be a combination of two measurement principles. For example, two different types of MEMS sensors, such as an accelerometer and a gyroscope, can be used.

[0015] According to a second design alternative to or supplementing the first design, the at least one sensor module may be an accelerometer. An accelerometer measures acceleration acting upon it in a manner known per se. Because it detects vibration and impact in addition to tilt measurement, the accelerometer provides more reliable measurements, especially when the gripping unit is stationary.

[0016] Applicable equally to all design schemes, the at least one sensor module can transmit measurement data to the control unit either as a voltage level electronically or via a current interface. Digital transmission is also possible. Each measuring axis of the sensor unit can have an electrical output terminal connected to the control unit. When the orientation of the sensor unit changes, the voltage applied to the corresponding output terminal also changes. For calibration, an initial value for 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 measured actual value 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] To measure the orientation of the gripping housing in space, sensor units can be arranged spaced apart from the gripping housing, in addition to being arranged on the gripping housing itself. For example, the sensor units may include optical detection devices, such as cameras, laser systems for cross-sectional detection, etc., where pre-given (image) data about the target orientation stored in the control unit can compensate for the detected actual measurements of the gripping housing's current orientation. The sensor units can be arranged according to the gripping unit and, for example, mounted on a frame or fixedly positioned relative to a base on a holding structure, such as a base, column, building wall or machine wall, the operating entrance of the gripper, or a similar location.

[0018] Furthermore, the gripping unit may have at least two pressure rollers, with the gripping plane tangentially arranged to the pressure rollers. Preferably, the sensor unit is arranged on the housing surface of the gripping housing plane. In particular, the housing surface or the surface segment occupied by the sensor unit is oriented parallel to the gripping plane. Preferably, the vertical direction is perpendicular to the housing surface in the target orientation, wherein the at least one correction angle can also be considered in the case of a tilted base. The sensor unit is securely and permanently connected to the gripping housing in a manner suitable for the purpose and can be threaded, riveted, bonded, etc., to the gripping housing. During the cutting process, the gripping unit can be placed on the fiber bundle in the gripping plane.

[0019] Two pressure rollers can be arranged in front of and behind the gripping rollers respectively along the longitudinal direction of the housing and are rotatably supported on the gripping housing. A possible third pressure roller can be arranged between the gripping rollers and rotatably supported on the gripping housing. Therefore, the pressure rollers ensure that the surface of the fiber bale enters below the gripping unit and can be rotatably driven by a driver. As the gripping unit moves past the fiber bale, the surface of the fiber bale is homogenized by the corresponding preceding pressure rollers along the cutting direction before the respective preceding gripping rollers act on the surface. Instead of pressure rollers or additional pressure rollers, a guide plate can also be used, which can define the gripping plane using its underside.

[0020] Preferably, the gripping unit has an adjusting device for displacing the gripping rollers relative to each other along the vertical axis of the housing. The control unit is communicatively connected to the adjusting device and configured to operate it during the forward and return travels such that the distance from the gripping plane to the gripping roller that is ahead in the cutting direction is less than the distance from the gripping plane to the gripping roller that is behind in the cutting direction. In other words, the gripping rollers can be displaced perpendicularly to each other or along a vertical direction in the target orientation of the gripping housing. The cutting direction can be changed once during the respective return travels, particularly from forward to return.

[0021] The frame is movable back and forth on the base along the machine's longitudinal direction, and fiber bales can be placed along this longitudinal direction. In the movable bale grabber configuration, the cutting direction corresponds to the grabber's travel direction on the base. A change in direction from forward to return is set for each round trip, wherein the grabber moves, for example, first to the left and then to the right on the bale array, or, in the case of multiple batches, at least only moves through a portion of the bale array.

[0022] The bag-grabbing machine can have a gantry structure. Specifically, the frame can have a first side frame and a second side frame, as well as at least one gantry profile connecting the two side frames. The side frames can define the machine's vertical axis, which is perpendicular to the base. If the base is flat, the machine's vertical axis can correspond to a plumb line direction. The frame can be constructed to be movable on the base so that the gripping unit can move above the bag. The side frames can have pulleys, wherein the pulleys of the first side frame are guided by slide rails mounted on the base so that the frame is guided along a particularly straight path of movement. The pulleys of the second side frame can slide on the base without further guidance. For height-adjustable guidance of the gripping unit, frame-side guide elements can be arranged on both side frames, these guide elements cooperating with gripping-side guide elements arranged on the gripping unit. The frame-side guide elements can be arranged on the inner sides of the side frames facing each other and can be constructed, for example, as guide rails. The frame-side guide elements can extend parallel to the machine's vertical axis. The guiding element on the gripping side may include pulleys that roll on a guide rail.

[0023] Furthermore, the grabber has an orientation device for orienting the grabbing housing relative to the frame. In this way, the grabbing housing can be oriented, particularly in target orientation, and, if necessary, corrected for misorientation to prevent the grabbing housing from tilting during height adjustment along guide elements on the frame side. In target orientation, the machine's vertical axis is preferably perpendicular to the grabbing plane. If the base is inclined, the machine's vertical axis can be oriented at a corresponding correction angle relative to the plumb line.

[0024] Preferably, the orientation device and the guiding device work together to orient the gripping housing about the lateral direction of the housing, that is, to adjust the pitch angle. For this purpose, at least one pair of guiding elements on the gripping side can be adjustable relative to each other in the longitudinal direction of the gripping housing on each end side of the gripping unit, so that the distance between the guiding elements forming the respective pair can be adjusted. For orientation, it is preferable to change only the position of one of the two guiding elements forming the respective pair relative to the lateral axis of the housing. In this way, the gripping housing can be oriented about its lateral axis to adjust the pitch angle. The adjustablely constructed guiding elements can be eccentrically supported guide rollers that roll on the guide elements on the frame side. The axis of rotation of the guide rollers can be oriented parallel to the lateral direction of the gripping housing. For example, the orientation device can have eccentric bolts, especially hexagonal bolts, on which the guide rollers are supported. On each end side of the gripping unit, the guiding elements can include multiple such guide rollers arranged in pairs and accommodating the frame-side guiding elements between them in a paired manner. The bottom pair of guide rollers can be configured to be adjustable to orient the gripping housing and have, for example, eccentric bearings. The top pair of guide rollers can have bearings that are fixed in position relative to the gripping housing.

[0025] Furthermore, the gripping unit, height-adjustable between the two side frames, can be suspended from the frame by means of a traction device. The traction device, such as the strap suspending the gripping unit, can be connected to a drive motor to adjust the height of the gripping unit. Preferably, an orientation device and a guide device work together to orient the gripping housing about the longitudinal direction of the housing. By changing and fixing the length of the traction device, the tilt or roll angle of the gripping housing about the transverse axis of the housing can be changed. In particular, the orientation device has a safety belt lock for each traction device so that the loop formed by the traction device can be adjusted and fixed in width.

[0026] Furthermore, the control unit can communicate with the display unit to visually display deviations from tolerances when an alarm is triggered. For this purpose, the display unit may include, for example, illumination elements arranged according to a predetermined geometry. The shape may be a line having at least one straight segment, an arc segment, and / or a curved segment. The illumination unit can be manipulated by the control unit according to a predetermined illumination scheme to indicate the orientation of the grabbing housing. For this purpose, the illumination scheme may include illumination elements emitting light in the same or different colors. For example, entering the target orientation may be indicated by green illumination elements, and leaving the target orientation may be indicated progressively using yellow, orange, and / or red depending on the degree of misorientation. This is particularly advantageous when the sensor unit provides measurement accuracy (where, for example, orientation can be determined with precise degree of accuracy). At the latest, in the case of pure red light, as a further countermeasure, the control unit may stop the grabbing machine and / or issue an audible warning signal. The warning signal can also be sent to a higher-level control center, which may include fixed equipment and / or mobile terminals. When deviations from tolerances occur, the control unit can issue escalated warnings, for example, through the following tiers: (1) activating an optical warning, (2) activating an acoustic warning, and (3) stopping the bag catcher. Further or other tiers are conceivable and possible. In this way, a person near the bag catcher can be directed to the error via a superior control device or a mobile terminal by a person further away from the bag catcher.

[0027] Another solution to the above-described task lies in the method of operating the aforementioned bag-grabbing machine, wherein a sensor unit measures the orientation of the grabbing housing in space and transmits the measurement value to a control unit, wherein the control unit triggers an alarm when the orientation of the grabbing housing is outside a pre-defined tolerance range. The advantages derived from the method according to the invention are the same as those described in conjunction with the bag-grabbing machine according to the invention, and thus briefly reference is made herein. It goes without saying that all the above-described designs of the bag-grabbing machine can be converted into the method, and vice versa.

[0028] The gripping unit can be oriented in target orientation during bag-grabbing machine commissioning, maintenance, repair work, or similar situations on-site. To determine the orientation of the gripping housing, or rather, obtain angular values, based on measurements from the sensor unit, the method can include a calibration step prior to the round trip. This calibration step determines the absolute zero value of the sensor unit, eliminating so-called zero-point error (“zero-point offset”). During the calibration step, the gripping housing is preferably in target orientation. Then, at least one initial measurement representing the target orientation is transmitted from the sensor unit to the control unit and stored as an initial value. An initial value is selected there. This initial value can then be used to further determine whether the actual orientation is within or outside the tolerance range.

[0029] Instead of using the calibration described above to determine the initial value, a standard value can also be used. This standard value can be stored in the control unit or manually entered, for example. For instance, the zero-point value of the sensor unit may have been provided by the manufacturer or measured in a disassembled state, where the sensor unit is positioned, for example, on a horizontal plane for measurement. In this regard, instead of the calibration step, or if necessary, the method may 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, tolerance ranges can be measured. For this purpose, the gripping housing can deflect up to its limit value and store the corresponding measurement signal from the sensor unit in the control unit. Alternatively or additionally, the tolerance range can be stored in the control unit or manually input. Here, possible correction angles based on a skewed base can be considered.

[0031] During and / or after the round trip, the method may further include at least one checking step in which the sensor unit transmits at least one actual measurement representing the current orientation (“actual orientation”) of the gripping housing to the control unit, wherein the control unit checks whether the actual measurement is outside the tolerance range by means of the at least one selected initial value. Preferably, the checking step is performed when the gripper stops, for example, during the placement of the bag array. In particular, during the checking step, the rack is always in the same position on its movement path. For example, the rack may be at one of the two endpoints, or one of the two inflection points, or the midpoint of the movement path. In particular, during the checking step, the rack is in the same position as when calibration was performed. If the checking step is performed during the round trip, when an incorrect orientation is determined, the control unit can store a delay, for example, a 1-minute delay, within which it checks whether the incorrect orientation still exists. In this way, short-term incorrect orientation due to local substrate unevenness does not trigger a warning. Attached Figure Description

[0032] Other features and advantages of the invention will become apparent from the following description of preferred embodiments.

[0033] In the picture:

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

[0035] Figure 2 Show Figure 1 Another perspective view of the bag-catching machine, showing the front frame without an entrance door;

[0036] Figure 3 Show Figure 1 The schematic simplified cross-sectional view of the grabbing unit of the bag grabber is shown in the figure, wherein the grabbing unit is oriented in the target orientation and the grabbing roller of the grabbing unit is set to the leftward travel direction;

[0037] Figure 4 Show Figure 3 The grasping unit is oriented in the target orientation, wherein the grasping roller is set to travel in the rightward direction;

[0038] Figure 5 Show Figure 3 The gripping unit in the housing is incorrectly oriented or tilted about the transverse axis of the housing, and the gripping roller is set to travel in the left direction;

[0039] Figure 6 Show Figure 5 The incorrectly oriented gripping unit in the process, wherein the gripping roller is set to travel in the rightward direction;

[0040] Figure 7 Show Figure 1 The schematic simplified side view of the bag grabber in the image shows the grabbing unit being misoriented or tilted about the longitudinal axis of the housing;

[0041] Figure 8 Show Figure 1 The end-side view of the grabbing unit of the bag grabber in the image; and

[0042] Figure 9 Show Figure 1 A detailed perspective view of the bag-grabbing machine, showing the grabbing unit without the housing cover. Detailed Implementation

[0043] exist Figures 1 to 2 The diagram illustrates a spinning preparation machine according to one embodiment of the invention, which is configured as a bale gripper 1. The bale gripper 1 is used in a known manner to open compressed fiber bales 2, particularly fiber bales composed of cotton, torn fibers, etc., which are placed side-by-side in multiple rows along the longitudinal direction X of the machine on a base 3. The bale gripper 1 has a frame 4 that is movable along the longitudinal direction X of the machine on the base 3. A gripping unit 5 is fixed and guided on the frame 4, and the gripping unit's height is adjustable along the vertical axis Z of the machine. The gripping unit 5 has a downward-facing gripping housing 6 that opens toward the base 3, in which two drivable gripping rollers 7 are arranged for gripping fiber bundles from the surface of the fiber bales 2.

[0044] exist Figure 1 , Figure 2 and Figure 7In this diagram, to illustrate the orientation of the grabber 1 in space, the longitudinal direction X, the transverse direction Y, and the vertical direction Z are marked. These are defined using a fixed Cartesian coordinate system and indicated by corresponding arrows. Assuming the base 3 is oriented perfectly horizontally, the vertical axis Z of the machine extends parallel to the vertical direction L. Thus, the base 3 lies within a horizontal reference plane H, with the vertical direction L perpendicular to this reference plane. However, the base 3 is typically not flat in its placement position; therefore, for the orientation of the grabbing housing 6, the vertical direction L or a reference plane H perpendicular to this orientation is considered, rather than the base 3 itself.

[0045] In addition, Figures 3 to 7 In order to clarify the orientation of the gripping shell 6 in space, the longitudinal direction X', the lateral direction Y', and the vertical direction Z' of the shell are marked. They are assigned in a Cartesian coordinate system with the main body of the gripping shell 6 fixed and indicated by corresponding arrows.

[0046] The frame 4 includes a front frame 9 on the front side 8 of the bag grabber 1 and a rear frame 11 on the rear side 10 of the bag grabber 1. Pulleys 12 are arranged on the rear frame 11, rolling on rails 13 mounted on the base 3 to guide the frame 4 along the longitudinal direction X of the machine. Additional pulleys 14 are arranged below the front frame 9, rolling directly on the base 3 during the reciprocating motion of the frame 4.

[0047] The bag-grabbing machine 1 has an electrical control unit 15 for monitoring and controlling the motion functions, sensing mechanisms, and actuation mechanisms of the bag-grabbing machine 1. Figure 2 The front frame 9 without an entrance door is shown, thus exposing the control unit 15. Manual control of the 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 optional input / output interfaces (not shown) arranged on the front frame 9.

[0048] Two spaced-apart gantry profiles 17 and 18 extend between the two side frames 9 and 11, rigidly connecting the two side frames 9 and 11 to each other. The gripping unit 5 is suspended from the frame 4 in a known manner by means of two spaced-apart traction devices 19, wherein the traction devices 19 are coupled to a drive to adjust the height of the gripping unit 5. This suspension method is described in WO 2019 / 211013A1, with particular reference to the description of its operation on page 9, line 25 to page 12, line 4, and the accompanying drawings.

[0049] According to Figure 2The front side 8 of the grabber 1 shown in the diagram, the frame 4, causes the grabbing unit 5 to move forward (to the left here) during the reciprocating stroke, and then move back (to the right here) after changing direction. Arrow A indicates forward movement and arrow B indicates return movement. After each reciprocating stroke, the height-adjustable grabbing unit 5 can be further lowered by a feed amount.

[0050] The gripping housing 6 has extensions in the longitudinal direction X', the transverse direction Y', and the vertical direction Z'. The gripping housing 6 has a basic box-shaped shape that opens downwards. The extension of the gripping housing in the transverse direction Y' can be more than twice the length of the extension in the longitudinal direction X'. Preferably, the ratio is between 2.3:1 and 3.5:1. Rotatably driven drive rollers 7 are rotatably supported in the gripping housing 6 and are arranged spaced apart from each other along the longitudinal direction X'. Fiber bundles stripped from the gripping rollers 7 are sucked away in a known manner by a suction device 25 arranged above the gripping rollers 7 and conveyed through a transport channel 20 to their next application. The transport channel 20 extends along the rear side 10 of the bag gripper 1 beyond the placement surface of the bag array.

[0051] Three pressure rollers 21 are rotatably supported on the gripping housing 6 in the longitudinal direction X' of the housing in front of and between the gripping rollers 7. The pressure rollers 21 press against the surface of the fiber bundle 2 and ensure that the surface of the fiber bundle 2 is below the gripping unit 5. A gripping plane E is defined below the pressure rollers 21, which is tangential to the pressure rollers 7 and oriented parallel to the longitudinal direction X' and the transverse direction Y' of the housing.

[0052] The gripping unit 5 has an engagement switching mechanism implemented using the adjusting device 22, causing the gripping rollers 7 to shift relative to each other and parallel to the vertical direction Z' within the gripping housing 6. Figure 8 The diagram shows an end view of the front frame 9. The adjustment device 22 includes a pivotable swing arm 24 at each end, pivoting around a central rotation point 23. For pivoting, an actuator (not shown) acts on the swing arm 24 at the end of the rear frame 11. The actuator is communicatively connected to a control unit 15. The control unit 15 is configured to operate the actuator during the respective reciprocating stroke such that the distance from the gripping plane E to the gripping roller 7', which is correspondingly forward in the travel direction, is less than the distance from the gripping plane E to the gripping roller 7', which is correspondingly rearward in the travel direction. In this way, the current consumption of the two gripping rollers 7', 7' is always kept as similar as possible.

[0053] according to Figure 3 The gripping unit 5 moves to the left and is (exemplarily here) heading towards A. Accordingly, the gripping roller 7' on the front left goes deeper into the fiber bundle 2 than the gripping roller 7' on the rear right. Figure 4 The gripping unit 5 moves to the right and is in (exemplarily here) return B, where the gripping roller 7 " on the right now acts more deeply into the fiber bundle than the gripping roller 7' on the left behind.

[0054] To achieve the maximum possible production volume and the most uniform bundle processing, the gripping housing 6 must be arranged or fixed in space with a defined, i.e., pre-given target orientation, such as... Figures 1 to 4 As shown in the diagram. In target orientation, the pitch angle α (here) formed between the vertical direction L and the longitudinal axis X' of the housing is 0 degrees. Furthermore, in target orientation, the roll angle β (here) formed between the vertical direction L and the lateral direction Y' of the housing is 0 degrees. However, due to events during the operation of the gripper 1, the gripping housing 6 may tilt around the housing's longitudinal axis X' and / or the housing's lateral axis Y'. In the case of the base 3 (which may be perpendicular to the machine's vertical axis X) tilting, the pitch angle α or roll angle β in target orientation is equal to the corresponding correction angle to compensate for the tilt of the base 3.

[0055] exist Figure 5 and Figure 6 In the middle, the gripping housing 6 tilts to the right about the housing's transverse axis Y', resulting in a pitch angle α (for example, here) of +2 degrees. Figure 5 As can be seen, in the left-pointing direction of travel (towards A), the two gripping rollers 7' and 7" are at the same height and the engagement switching is almost eliminated. According to Figure 6 After the direction changes (return to B), the vertical shift based on the engagement switch, now the front gripping roller 7, to the right, is positioned at an inclined horizontal or pitch angle α, deeper into the material of the fiber pack 2 and unevenly processes the pack surface.

[0056] according to Figure 8 The gripping housing 6 is tilted clockwise or backward around the housing's longitudinal axis X', resulting in a roll angle β (for example, here) of +2 degrees. This tilted position serves as the tilted surface entering the bag array.

[0057] To measure the actual orientation, a sensor unit 26 is provided, positioned relative to the gripping housing 6. The sensor unit 26 is communicatively connected to a control unit 15, which is configured to trigger an alarm when the actual orientation of the gripping housing 6 is outside a pre-defined tolerance range. The control unit 15 is also connected to a display unit, which can issue an optical alarm in the event of an incorrect orientation. For example, the display unit may have a light-emitting diode strip 27, which is externally and well-visible from both sides on the housing of the frame 4, and more preferably on the housing of the gantry profiles 17, 18. The display unit may also include a display 28 of the console 16. Furthermore, the display unit may also include a mobile terminal (not shown).

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

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

[0060] Furthermore, sensor unit 26 is arranged on the inner side of the housing wall 31 of the gripping housing 6, therefore sensor modules 29 and 30 are located on the inner side of the housing wall 31 of the gripping housing 6. Figure 1 and Figure 2 The figures are indicated by dashed lines. As shown here, the housing wall 31 may be the upper housing wall, i.e., the top cover of the gripping housing 6. Preferably, the housing wall 31 is constructed to be flat and oriented parallel to the gripping plane E where the sensor unit 26 is fastened. The sensor unit 26 may be fastened to the gripping housing 6 by means of screws, rivets, adhesives or similar means to securely define a position on the gripping housing 6.

[0061] The target orientation is stored in the control unit 15, and this target orientation can be predetermined by the manufacturer. In the target orientation, the gripping housing 6 (here, for example) can be oriented in the housing longitudinal direction X' and the housing transverse direction Y', respectively, parallel to the horizontal reference plane H. Preferably, the housing wall 31, or the area 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, especially when the correction angle should be considered based on the inclined base 3.

[0062] A tolerance range can be predefined in control unit 15, within which deviations from the target orientation are tolerable. For example, the tolerance range could include a pitch angle range of + / -5 degrees and a roll angle range of + / -10 degrees. The target orientation, or zero point, may, but is not required to, be at the midpoint of the tolerance range. In principle, it is also permissible for the tilt position in one direction to be greater than that in another. Taking pitch angle α as an example, the tolerance range could 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 roll angle range may also influence each other. An incorrect orientation of the gripping housing 6 outside the tolerance range causes control unit 15 to trigger an alarm.

[0063] To orient the gripping housing 6 in the target orientation or to correct misorientation, the gripper 1 has an orientation device 32, which (here, for example) works in conjunction with a traction device 19 for height adjustment and a guide device 33 for the gripper 1, as described in [reference needed]. Figure 8 and Figure 9 .

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

[0065] Furthermore, a gripping-side guide element 35 is arranged on each end side of the gripping housing 6, which is supported on a guide profile 34. The gripping-side guide element 35 is described in detail below using one of the two end sides as an example, although the structures on both end sides may be identical. Each end side is provided with four guide rollers 36, 37, 38, 39 and one support roller 40, which are rotatably supported on the gripping housing 6. The rotation axes of the guide rollers 36, 37, 38, 39 are parallel to the transverse direction Y' of the housing, and the rotation axis of the support roller 40 is parallel to the longitudinal direction X' of the housing. The guide rollers 36, 37, 38, 39 are paired, forming an upper pair of rollers 36 and 37 and a lower pair of rollers 38 and 39. The guide profiles 34 of the corresponding side frames 9 and 11 are sandwiched between the respective pairs of guide rollers 36, 37, 38, 39. As the gripping housing 6 is raised and lowered, guide rollers 36, 37, 38, and 39 roll on the side wings of guide profile 34. Support roller 40 is positioned between the gripping housing 6 and guide profile 34 and rolls on the central beam of guide profile 34 pointing towards the gripping housing 6.

[0066] To orient the gripping housing 6 about the housing's transverse axis Y', i.e., to correct the pitch angle α, the orientation device 32 has two eccentric bolts 41, 42, specifically 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 fixedly supported on the gripping housing 6 in a relative position. For example, if the two bolts 41, 42 are rotated, and viewed from the front side 8 of the gripper 1 towards the rear frame 11, the lower pair of guide rollers 38, 39 shift to the left, causing the gripping housing 6 to rotate clockwise about the housing's transverse direction Y'. In this way, a negative pitch angle α can be corrected. Similarly, a positive pitch angle α can be corrected by rotating the two bolts 41, 42 in the opposite direction. The adjustment of the gripping housing 6 about the housing's transverse axis Y' can be performed until the pitch angle α is at least approximately 0 degrees or equal to the corresponding correction angle.

[0067] To orient the gripping housing 6 about its longitudinal axis X', i.e., to correct the roll angle β, the orienting device 32 has a fixing device 43 to adjust and fix the lengths of the two traction devices 19, the two ends of which are suspended from the gripping housing 6. Specifically, the fixing device 43 is a seatbelt lock to adjust and fix the loop formed by the traction devices 19 in width. The corresponding traction devices 19 can be lengthened or shortened until the roll angle β is at least approximately 0 degrees or equal to the corresponding correction angle.

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

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

[0070] During and / or after the round trip of the grabber 1, the control unit 15 checks whether the measured value transmitted by the sensor unit 26 is within the permissible range. If the measured value deviates from the permissible range, it indicates that the current orientation (“actual orientation”) of the grabbing 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 alarm is triggered.

[0071] The invention is not limited in its implementation to the preferred embodiments given above. Rather, many variations are conceivable, which also utilize the solution in principle in different types of embodiments. All features and / or advantages derived from the claims, description, or drawings, including structural details or spatial arrangements, can be essential to the invention not only in themselves but also in various combinations.

[0072] List of reference numerals in the attached diagram:

[0073] 1. Bag grabber with 36 guide rollers

[0074] 2 fiber-encased guide rollers 37

[0075] 3 Base 38 Guide Rollers

[0076] 4. Frame 39 guide rollers

[0077] 5 gripping units with 40 support rollers

[0078] 6. Grab the housing bolt 41

[0079] 7. Gripping rollers with 42 bolts

[0080] 8. Front 43 fixing device

[0081] 9 side frames

[0082] 10 Rear side

[0083] 11 side frames

[0084] 12 pulleys

[0085] 13. Slide rail α pitch angle

[0086] 14. Pulley β-roll angle

[0087] 15. Control Unit A proceeds to...

[0088] 16. Console B returns

[0089] 17. Gantry Profile E Grabbing Plane

[0090] 18. Portal profile H-reference plane

[0091] 19. Traction device L vertical direction

[0092] 20. Transport channel x machine longitudinal direction

[0093] 21 Pressure roller Y-axis machine transverse direction

[0094] 22 Adjustment device Z machine vertical direction

[0095] 23. Rotation point X' in the longitudinal direction of the shell

[0096] 24. The lateral direction of the swing arm Y' housing

[0097] 25. Vertical direction of the suction device Z' housing

[0098] 26 Control Unit

[0099] 27 LED strips

[0100] 28 monitors

[0101] 29 Sensor Module

[0102] 30 Sensor Modules

[0103] 31 Shell wall

[0104] 32 Orientation Devices

[0105] 33. Guiding Device

[0106] 34 Guide profiles

[0107] 35. Guiding element

Claims

1. A bale grabber (1) for opening fiber bales (2) placed on a substrate (3), the bale grabber having a frame (4) and a height-adjustable grabbing unit (5) fixed and guided on the frame, wherein, The gripping unit (5) has a gripping housing (6) and two gripping rollers (7), the gripping housing having an extension along the longitudinal direction (X'), the transverse direction (Y'), and the vertical direction (Z'); the two gripping rollers are arranged spaced apart from each other in the gripping housing (6) along the longitudinal direction (X') for gripping fibers from the fiber bundle, wherein a sensor unit (26) is provided for measuring the orientation of the gripping housing (6) in space, wherein the sensor unit (26) is arranged in a position defined relative to the gripping housing (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 housing (6) is outside a predetermined tolerance range, and characterized in that the sensor unit (26) is arranged on the gripping housing (6) and configured to measure the orientation of the gripping housing (6) relative to the vertical direction (L).

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

3. The bag-grabbing machine (1) according to claim 2, characterized in that, The sensor unit (26) has at least two sensor modules (29, 30) configured to measure pitch angle (α), which are arranged at intervals along the lateral direction (Y') of the housing on one end of the gripping housing (6).

4. The bag-grabbing machine (1) according to any one of claims 1 to 3, characterized in that, The sensor unit (26) has at least one sensor module (29, 30) configured to measure the roll angle (β) between the housing in the lateral direction (Y') and a horizontal reference plane (H) perpendicular to the vertical direction (L), or the horizontal reference plane (H).

5. The bag-grabbing machine (1) according to any one of claims 2 to 4, characterized in that, The at least one sensor module (29, 30) is a tilt sensor or an acceleration sensor.

6. The bag-grabbing machine (1) according to any one of claims 1 to 5, 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') and the transverse direction (Y') of the housing is tangentially arranged with respect to the pressure rollers (21).

7. The bag-grabbing machine (1) according to claim 6, characterized in that, The gripping unit (5) has an adjustment device (22) for displacing the gripping rollers (7) relative to each other parallel to the vertical direction (Z') of the housing. The control unit (15) is communicatively connected to the adjustment device (22) and configured to manipulate the adjustment device (22) during the reciprocating stroke of the two gripping rollers (7) gripping fibers from the fiber bundle (2) such that the distance from the gripping plane (E) of the gripping roller (7'; 7") that is ahead of the two gripping rollers (7) in the cutting direction (A, B) is less than the distance from the gripping plane (E) of the gripping roller (7") that is behind the two gripping rollers (7"; 7') in the cutting direction (A, B).

8. The bag-grabbing machine (1) according to any one of claims 1 to 7, characterized in that, The grabber (1) has an orientation device (32) for orienting the grabbing housing (6) relative to the frame (4).

9. The bag-grabbing machine (1) according to any one of claims 1 to 8, characterized in that, The frame (4) has a first side frame (9) and a second side frame (11) and at least one gantry profile (17, 18) connecting the two side frames (9, 11) to each other. In order to guide the gripping unit (5) in 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 the gripping-side guide elements (35) arranged on the gripping unit (5).

10. The bag-grabbing machine (1) according to claim 9, characterized in that, The gripping side guide element (35) includes eccentrically supported guide rollers (38, 39) that roll on the frame side guide element (34).

11. The bag-grabbing machine (1) according to any one of claims 1 to 10, characterized in that, The control unit (15) is communicatively connected to the display units (27, 28), wherein the display units (27, 28) visually display deviations from the tolerance range when an alarm is triggered.

12. A method for operating a bag-catching machine according to any one of claims 1 to 11, characterized in that, The sensor unit (26) measures the orientation of the gripping housing (6) in space and transmits the measured value to the control unit (15), wherein the control unit (15) triggers an alarm when the orientation of the gripping housing (6) is outside a predetermined tolerance range.

13. The method according to claim 12, characterized in that, Prior to the round-trip stroke of the two gripping rollers gripping fibers from the fiber bundle (2), the method includes either a calibration step or an initial step, in which the gripping housing (6) is in target orientation and at least one initial measurement is transmitted by the sensor unit (26) to the control unit (15) and stored as an initial value and selected in the control unit (15); in the initial step, at least one initial value representing the target orientation stored in the control unit (15) is selected.

14. The method according to claim 13, characterized in that, The method includes at least one inspection step during and / or after the round trip, in which the sensor unit (26) transmits at least one actual measurement value representing the current orientation of the gripping housing (6) to the control unit (15), wherein the control unit (15) checks whether the actual measurement value is outside the tolerance range by means of the selected at least one initial value.

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