METHOD FOR DETERMINING THE CONDITION OF A LIFTING ROPE OF A LIFTING SYSTEM

Abstract

The invention relates to a method for determining a rope condition of a hoisting rope (20) and a hoisting system (10), wherein a sensor device (25) with at least a first sensor unit (70), a data memory (35) and a hoisting rope (20) are provided, wherein the hoisting rope (20) is moved past the first sensor unit (70) over an available rope length, wherein the first sensor unit (70) generates a first sensor signal, wherein a first signal profile of the first sensor signal is determined as a function of the first rope position (p1(I)) as a first reference characteristic (100) of the hoisting rope (20), wherein a rope section (110) of the hoisting rope (20) is measured at the first sensor unit (70), wherein the first sensor unit (70) generates a second sensor signal as a function of a second rope position (p2(I)) of the hoisting rope (20), wherein a second signal profile (120) is determined as a function of the second rope position (p2(I)) is determined,wherein the second signal curve (120) is assigned to a subsection (116) of the first reference characteristic (100), wherein the subsection (116) of the first reference characteristic (100) assigned to the second signal curve (120) is updated by the second signal curve (120), wherein the updated reference characteristic is stored as a second reference characteristic (125).

Description

[0001] The invention relates to a method for determining a rope condition of a lifting rope of a lifting system according to patent claim 1 and a lifting system according to patent claim 13.

[0002] EP 4 065 498 A1 discloses an arrangement for monitoring an elevator having an elevator rope. The elevator rope is guided past an inductive sensor positioned so that a magnetic field generated by the inductive sensor, which extends at least partially across the elevator rope, is evaluated by a control device.

[0003] It is an object of the invention to provide an improved method for determining a rope condition of a lifting rope of a lifting system and an improved lifting system.

[0004] This object is achieved by means of a method according to claim 1 and a lifting system according to claim 13. Advantageous embodiments are specified in the dependent claims.

[0005] It has been recognized that an improved method for determining the rope condition of a hoisting rope of a hoisting system and an improved hoisting system for a large-scale industrial facility and / or other goods handling location can be provided by providing a sensor device with at least a first sensor unit, a data storage device, and a hoisting rope of the hoisting system. The hoisting rope is moved past the first sensor unit over an available rope length, wherein the first sensor unit generates a first sensor signal, which characterizes an interaction between the first sensor unit and the hoisting rope moved past the first sensor unit, as a function of a first rope position of the hoisting rope. A first signal curve of the first sensor signal is determined as a first reference characteristic of the hoisting rope as a function of the first rope position and is stored in the data storage device.A section of the hoisting rope that is less than or equal to the available rope length of the hoisting rope is moved past the first sensor unit after the first reference characteristic of the hoisting rope has been determined, wherein the first sensor unit generates a second sensor signal that characterizes an interaction between the first sensor unit and the section of rope moved past the first sensor unit, depending on a second rope position of the hoisting rope. A second signal curve of the second sensor signal is determined depending on the second rope position. The second signal curve of the second sensor signal is assigned to a subsection of the first reference characteristic, wherein the subsection of the first reference characteristic assigned to the second signal curve is updated by the second signal curve of the second sensor signal. The updated reference characteristic is stored as the second reference characteristic in the data memory.

[0006] This design has the advantage that the second reference characteristic can be determined while the lifting system is in operation. This eliminates the need for a shutdown or maintenance interruption to determine the second reference characteristic. This makes the method particularly suitable for large-scale industrial plants that operate essentially continuously throughout the day and / or month.

[0007] In a further embodiment, the sensor device has a second sensor unit, which is arranged at a distance from the first sensor unit and rests against the hoisting rope. The second sensor unit provides information about a first running direction of the hoisting rope guided past the second sensor unit over the available rope length upon determination of the first reference characteristic. The second sensor unit provides information about a second running direction of the rope section of the hoisting rope guided past the second sensor unit, wherein, depending on the second running direction of the rope section, the second sensor signal is further processed such that the first reference characteristic and the second signal curve are determined with the same running direction.This design has the advantage that the running direction can be reliably determined by the second sensor unit, so that a reliable analysis and assignment of the second sensor profile to the first reference characteristic is possible with only minor deviations.

[0008] In a further embodiment, the second sensor unit comprises a speed sensor. Upon movement of the hoisting rope over the available rope length, the speed sensor provides a first speed signal corresponding to a first speed of the hoisting rope guided past the first sensor unit. Upon movement of the rope section of the hoisting rope, the speed sensor provides a second speed signal corresponding to a second speed of the rope section guided past the first sensor unit. Information about the movement of the hoisting rope can be easily determined using the speed sensor.

[0009] In a further embodiment, the second sensor unit has a rolling element coupled to the speed sensor. The rolling element rests against the hoisting cable. As the hoisting cable moves, the rolling element rolls along the hoisting cable, and the speed sensor provides the first speed signal or the second speed signal, with the first running direction being determined based on the first speed signal and the second running direction being determined based on the second speed signal. This configuration has the advantage that the first and / or second speed of the hoisting cable can be reliably determined by the rolling element rolling along the hoisting cable and the mechanical connection of the second sensor unit to the hoisting cable.

[0010] In a further embodiment, the second sensor unit is arranged at a predefined distance from the first sensor unit, wherein the detection of the hoisting rope with the first sensor unit begins at a starting point, wherein the first rope position relative to the starting point is determined as a function of the first speed signal. This allows the first rope position to be reliably determined and a particularly precise first reference characteristic to be determined.

[0011] In a further embodiment, the second signal profile of the sensor signal is assigned to the first reference characteristic by means of pattern recognition, in particular cross-correlation, and / or in particular a time-warping algorithm, in particular a dynamic time-warping algorithm, and / or a self-learning algorithm. This allows for compensation of rope stretching caused by heavy loads or progressive aging of the lifting rope, so that a reliable assignment of the second signal profile to the first reference characteristic is possible even when the lifting rope is stretched.

[0012] In a further embodiment, the first reference characteristic is linked to a first piece of time information from the temporal acquisition of the first sensor signal and stored with the first piece of time information. The second reference characteristic is linked to a second piece of time information from the temporal acquisition of the second sensor signal and stored. This allows an epigenetic fingerprint of the lifting rope, which changes over the lifetime of the lifting rope, to be stored in the data memory.

[0013] In a further embodiment, the second reference characteristic is evaluated based on the first reference characteristic, with a status of the lifting rope being determined and output based on the result of the evaluation. By repeating the process several times and each time saving the most recent reference characteristic, a history of the lifting rope can be created, which offers additional evaluation options during a lifting rope inspection.

[0014] In a further embodiment, the second speed at the second rope position is compared with a predefined minimum speed, wherein if the minimum speed is exceeded by the second speed at the second rope position, the second sensor signal is taken into account for determining the second rope loss, wherein in particular if the second speed at the second rope position falls below the minimum speed, the second sensor signal is not taken into account for determining the second rope loss. This embodiment has the advantage that implausible second sensor signals are avoided by the minimum speed. For example, the minimum speed can be at least 0.1 m / s, in particular at least 0.2 m / s. The speed at which the lifting rope is moved should not, however, exceed 50 m / s.

[0015] In a further embodiment, the first sensor signal and / or the second sensor signal is smoothed and / or pre-filtered before the first sensor signal and / or the second sensor signal is evaluated, wherein in particular a Fast Fourier Transformation and / or a Wavelet Transformation, in particular a Direct Wavelet Transformation, and / or a low-pass filter is applied for filtering. Additionally or alternatively, the first sensor signal and / or the second sensor signal is compared with a predefined minimum threshold value, wherein the first signal curve is determined based on the first sensor signal exceeding the predefined minimum threshold value, wherein the second signal curve is determined based on the second sensor signal exceeding the predefined minimum threshold value. The minimum threshold value can, for example, be inclusive of 5 percent to 10 percent of an expected maximum leakage flux change.This allows noise to be masked out in healthy areas of the lifting rope.

[0016] In a further embodiment, the rope length for determining the second signal profile is determined after a predefined time interval, for example, from 1 hour up to and including 12 hours, or after a predefined number of lifting cycles have been performed. This embodiment has the advantage of ensuring reliable evaluation and determination of the first and second reference characteristics. This allows the lifting rope to be evaluated and analyzed regularly, for example, at shift changes and as needed. This embodiment also has the advantage that the intercomparison of the reference characteristics enables automated evaluation, for example, with a trend analysis or indications of frequently worn rope areas.

[0017] In a further embodiment, the available cable length is advanced at the first sensor unit at at least one predefined minimum speed, wherein the minimum speed is preferably at least 0.1 m / s, in particular at least 0.2 m / s.

[0018] An improved lifting system can be provided in that the lifting system is designed in particular for a large-scale industrial plant, in particular a rolling mill and / or a continuous casting machine and / or a goods handling center, wherein the lifting system is designed to carry out the method described above. Furthermore, the lifting system has at least one lifting rope, wherein the lifting system has a lifting capacity of at least 20 t.

[0019] The invention is explained in more detail below with reference to the figures. These show: FIG 1 shows a schematic representation of a lifting system according to a first embodiment; FIGS. 2A and 2B show a sensor device of the FIG 1 shown lifting system from different perspective views on the lifting rope; FIG 3 a flow diagram of a method for operating the FIGN 1 and 2A, 2B shown lifting system; FIG 4 a schematic first diagram of a first reference characteristic; FIG 5 a schematic second diagram of a second signal curve of a second sensor signal over a second cable position; and FIG 6 a second reference characteristic of the FIGN 1 and 2 shown lifting rope; FIG 7 a second reference characteristic of a ready-to-discard lifting rope; FIG 8 a schematic representation of a lifting system according to a second embodiment; and FIG 9 a sensor device of the FIG 8 lifting system shown.

[0020] FIG 1 shows a schematic representation of a lifting system 10 according to a first embodiment.

[0021] The lifting system 10 is designed, for example, as a crane, in particular, for example, as a gantry crane. The lifting system 10 can, for example, be designed to be mounted in a production facility, for example, in a building of a continuous casting machine or a composite casting-rolling plant, or another building used for steel or metal production, in order to lift heavy objects, in particular, for example, ladles, using a lifting rope 20. The lifting system 10, in particular the lifting rope 20, is subject to high loads and is subject to corresponding wear and aging.

[0022] In order to determine the wear and aging, the lifting system 10 has, in addition to the lifting rope 20, a control unit 15, a sensor device 25, a lifting device 30 and a support device 31.

[0023] The control unit 15 has a data memory 35, an evaluation device 40, and a data interface 45. The data interface 45 is connected to the evaluation device 40 via a first data connection 50. Furthermore, the evaluation device 40 is connected to the data memory 35 via a second data connection 55. The data interface 45, in turn, is connected to the sensor device 25 via a third data connection 60.

[0024] The carrier device 31 can, for example, be a trolley (in Figur 1 not shown) which is arranged to be movable along a crane bridge 33 of the lifting system 10.

[0025] The lifting device 30 can, for example, have a drive unit, which is arranged, for example, on the trolley. The drive unit is designed to wind up or unwind the lifting cable 20 and to lift or lower loads by means of the lifting cable 20 or the lifting gear arranged thereon, for example.

[0026] During operation of the lifting system 10, the lifting rope 20 is frequently moved. The lifting rope 20 has a plurality of stranded wires. The wires can be made, for example, from ferromagnetic and / or austenitic steel. Over the service life of the lifting rope 20, the lifting rope 20 wears, on the one hand, due to the loads lifted by means of the lifting rope 20 and the associated elongation of the lifting rope, and on the other hand, due to the bending of the lifting rope 20, which occurs, for example, during winding and unwinding of the lifting rope 20. This causes wire breakage. Over the course of its service life, the lifting rope 20 wears due to individual wires of the lifting rope 20 breaking locally. If breakages occur frequently over a predefined length, the lifting rope 20 is considered worn and must be replaced to prevent accidental tearing of the lifting rope 20, for example under heavy loads, or accidental further breakage.

[0027] The sensor device 25 is mechanically connected to the trolley and arranged on the hoist cable 20. The sensor device 25 remains on the trolley during operation of the lifting system 10 and is not removed. The hoist cable 20 is guided through the sensor device 25.

[0028] FIGN 2A und 2B show the sensor device 25 of the FIG 1 shown lifting system 10 from different perspective views on the lifting rope 20.

[0029] The sensor device 25 comprises a guide roller assembly 65, a first sensor unit 70, and at least one second sensor unit 75. The guide roller assembly 65 is designed to guide the lifting cable 20 in the sensor device 25 and to establish a predefined distance between the first sensor unit 70 and the lifting cable 20.

[0030] The first sensor unit 70 can, for example, comprise a magnetic field generator and a magnetic field sensor. The magnetic field generator can, for example, comprise an electric coil or a permanent magnet that acts on the lifting cable 20. The magnetic field sensor is designed to provide a first sensor signal corresponding to the lifting cable 20 guided through the magnetic field of the magnetic field generator.

[0031] The second sensor unit 75 can, for example, have a rolling element 80 and a speed sensor 90, wherein the rolling element 80 rests against the lifting cable 20 at least at a contact point 85. In the first embodiment of the lifting system 10, the rolling element 80 can be designed, for example, as a tachometer wheel 81. Another design of the rolling element 80 is also possible. In particular, for example, the rolling element 80 can be omitted. If the lifting cable 20 is moved, the rolling element 80 rolls on the lifting cable 20. The speed sensor 90 detects a first speed of the lifting cable 20 guided past the second sensor unit 75. The contact point 85 is arranged at a distance a from the first sensor unit 70. Furthermore, it is also possible for the first speed of the lifting cable 20 to be determined contactlessly by the speed sensor 90.In this case, for example, the speed sensor 90 can be arranged at the distance a from the first sensor unit 70.

[0032] FIG 3 shows a flowchart of a method for operating the FIGN 1 and 2A, 2B shown lifting system 10. FIG 4 shows a schematic first diagram of a first reference characteristic 100. FIG 5 shows a schematic second diagram of a second signal curve 120 of a second sensor signal over a second cable position p2(I). FIG 6 shows a second reference characteristic 125 of the FIGN 1 and 2 shown lifting rope 20.

[0033] The process described below is preferably carried out over the entire service life of the lifting rope 20 and is repeated regularly in parts. For this purpose, the lifting rope 20 is preferably mounted on the lifting device 30 at the beginning of its service life in a preferably new or barely worn condition.

[0034] Before the start of the method, a minimum speed and preferably a predefined reference length are stored in the data memory 35. The minimum speed can be at least 0.1 m / s, in particular at least 0.2 m / s.

[0035] In a first method step 305, the lifting rope 20 is mounted in the lifting system 10 essentially in a new or barely worn condition, and the sensor device 25 is permanently mounted on the lifting rope 20, so that during each lifting or lowering operation or during each movement of the lifting rope 20 by the lifting device 30, the lifting rope 20 is guided past the sensor device 25.

[0036] In a second method step 310, for example, the lifting rope 20 is completely unwound or completely wound up once. Once the lifting rope 20 is wound up or completely unwound, a starting point 95 of the lifting rope 20 is defined. The starting point 95 serves as a reference point on the lifting rope 20. The first rope position p1(I) can be referenced and related to the starting point 95. The starting point 95 thus serves as the "zero point" for the first rope position.

[0037] In a third method step 315, the lifting rope 20 is guided past the sensor device 25 at the minimum speed in a first direction of travel, starting from the starting point 95. The sensor device 25 is activated in the third method step 315.

[0038] For example, the magnetic field generator generates a magnetic field. The magnetic field of the magnetic field generator acts on the lifting cable 20 and the individual wires of the lifting cable 20. The material of the lifting cable 20 modifies the magnetic field flux. In this embodiment, the magnetic field sensor is arranged at a distance from the magnetic field generator and provides a first sensor signal depending on the detected magnetic field. The first sensor signal is transmitted via the third data connection 60 to the data interface 45 and from the data interface 45 via the first data connection 50 to the evaluation device 40. The evaluation device 40 detects the first sensor signal. The minimum speed ensures that the first sensor signal can be further processed by the evaluation device 40.

[0039] The evaluation device 40 can filter and / or smooth the first sensor signal before further processing, or the control unit 15 can have an additional first filter for filtering and / or first smoother for smoothing the first sensor signal, wherein in particular a Fast Fourier Transformation and / or a Wavelet Transformation, in particular a Direct Wavelet Transformation, is applied for filtering.

[0040] In the third method step 315, the rolling element 80, designed as a speedometer wheel 81, rolls on the hoisting cable 20, and the speed sensor 90 provides, as part of a first speed signal, information about the first speed of the hoisting cable 20, for example, via the third data connection of the data interface 45 and via the first data connection 50 of the evaluation device 40. The evaluation device 40 detects the first speed signal. The first running direction can be determined based on the first speed signal and the starting point 95.

[0041] The evaluation device 40 can filter and / or smooth the first speed signal before further processing, or the control unit 15 can have an additional second filter for filtering and / or a second smoother for smoothing the first speed signal, wherein in particular a Fast Fourier Transformation and / or a Wavelet Transformation, a Direct Wavelet Transformation, is applied for filtering.

[0042] The lifting rope 20 is wound up or unwound over an available rope length starting from the starting point 95 up to, for example, a maximally movable end 105 and is guided past the sensor device 25.

[0043] In a fourth method step 320 following the third method step 315, the evaluation device 40 determines a first cable position p1(I) relative to the starting point 95 corresponding to the respectively detected first sensor signal based on the distance a and the speed information of the first speed signal via the hoisting cable 20. In other words, a respective first cable position p1(I) of the corresponding first sensor signal is determined at a distance of a specific length of the hoisting cable 20 from the starting point 95.

[0044] In a fifth method step 325 following the fourth method step 320 (cf. FIG 4 ), the evaluation device 40 determines a first signal profile of the first sensor signal for the respectively assigned first cable position p1(I) between the starting point 95 and the end 105. The evaluation device 40 stores the first signal profile in the data memory 35 as a first reference characteristic 100. Furthermore, the evaluation device 40 stores information about the first running direction with which the first reference characteristic 100 was determined.

[0045] Furthermore, the evaluation device 40 preferably stores a first time information item associated with the first reference characteristic 100, which essentially corresponds to the detection time of the first sensor signal. The first reference characteristic 100 forms a first fingerprint of the lifting cable 20, which is unique to the respective lifting cable 20.

[0046] The first sensor signal correlates with a leakage flux change D of a magnetic flux in the hoisting rope 20. The leakage flux change D of the first sensor signal corresponds to an interruption / weakening of the magnetic flux, for example due to one or more wire breaks at the associated first rope position p1(I).

[0047] The first reference characteristic 100 (cf. Figur 4 ), for example, has a jagged first signal profile of the first sensor signal across the first cable position p1(I). The greater the amplitude of the first sensor signal at an associated first cable position p1(I), the stronger the leakage flux change D at the respective associated first cable position p1(I). Therefore, if the first sensor signal has a high amplitude, the hoisting cable 20 has an irregularity, in particular one or more wire breaks, at the respective associated first cable position p1(I).

[0048] The first to fifth method steps 305 to 325 represent, for example, an initialization process of the lifting rope 20. The initialization process can be performed during or shortly after installation of the lifting rope 20 in the lifting system 10.

[0049] After the initialization process, the lifting system 10 can be used as intended to lift or lower loads using the lifting rope 20. The method steps described below are carried out cyclically and regularly during the use of the lifting rope 20. It is particularly advantageous if the method steps described below are carried out, for example, at a shift change, for example every eight hours. Of course, a different time interval is also possible. The following method steps are started and carried out independently, preferably by the control unit 15. At the beginning of the following method steps, the lifting rope 20 does not have to be completely wound or unwound, but can also be in an intermediate position between the starting point 95 and the end 105 on the sensor device 25.

[0050] In a sixth method step 330, a cable section 110 of the lifting cable 20 is preferably guided past the sensor device 25 at the minimum speed. The cable section 110 can be located between the starting point 95 and an end 105 of the lifting cable 20. The cable section 110 can be shorter than the maximum cable length of the lifting cable 20 between the starting point 95 and the end 105 of the lifting cable 20. However, the cable section 110 can also extend over the maximum cable length of the lifting cable 20 between the starting point 95 and the end 105 of the lifting cable 20. The cable section 110 begins at a cable section start point 111 and ends at a cable section end point 112.

[0051] Analogous to the third method step 315, based on the interaction between the first sensor unit 70 and the passing hoisting cable 20, the first sensor unit 70 provides a second sensor signal instead of the first sensor signal. The second sensor signal is transmitted via the third data connection 60 to the data interface 45 and from the data interface 45 via the first data connection 50 to the evaluation device 40. The evaluation device 40 detects the second sensor signal. The minimum speed ensures that the second sensor signal can be further processed by the evaluation device 40.

[0052] The second sensor signal correlates with a leakage flux change D of the magnetic flux at a second cable position p2(I) in the cable section 110 of the lifting cable 20. The leakage flux change D of the second sensor signal corresponds to an interruption and / or weakening and / or a change in the magnetic flux, for example due to one or more wire breaks, within the lifting cable 20.

[0053] In the sixth method step 330, the unwinding element 80 rolls on the hoisting cable 20 offset from the cable section 110, and the speed sensor 90, driven by the unwinding element 80, provides, as part of a second speed signal, information about a second speed of the hoisting cable 20, for example, via the third data connection 60 to the data interface 45 and via the first data connection 50 to the evaluation device 40. The evaluation device 40 detects the second speed signal.

[0054] In a seventh method step 335 following the sixth method step 330, the evaluation device 40 determines the second cable position p2(I) based on the distance a and the speed information of the second speed signal. In the seventh method step 335, the second cable position p2(I) maps information from the cable section 110 already guided past the first sensor unit 70 to the cable section start point 111. In the seventh method step 335, the second cable position p2(I), the cable section start point 111, and the cable section end point 112 do not yet have an assignment to the start point 95 of the first reference characteristic 100, but rather refer only to the determined cable section start point 111 of the cable section 110 guided past the first sensor unit 70.

[0055] At the end of the cable section 110 passing the first sensor unit 70, the cable section end point 112 is reached. In the sixth and seventh method steps 330, 335, the beginning of the detection of the second speed signal at the cable section start point 111 on the cable section 110 thus serves as a reference for the second cable position p2(I).

[0056] In an eighth method step 340 following the seventh method step 335, the evaluation device 40 compares the second speed at the second cable position p2(I) with the minimum speed stored in the data memory 35. If the minimum speed is undershot, the further method steps are not continued for the respective second sensor signal assigned to the second cable position p2(I). If the minimum speed is exceeded by the second speed at the second cable position p2(I), the evaluation device 40 proceeds to the ninth method step 345.

[0057] In the ninth method step 345, the evaluation device 40 determines a second signal curve 120 of the second sensor signal for the respectively assigned second cable position p2(I) of the cable region 110.

[0058] Furthermore, based on the second speed signal, the evaluation device 40 checks a second direction of travel in which the hoisting rope 20 was guided past the sensor device 25 in the sixth method step 330. If the second direction of travel corresponds to the first direction of travel of the first reference characteristic 100, the evaluation device 40 continues with the determined second signal profile 120. If the second direction of travel is opposite to the first direction of travel, the evaluation device 40 inverts the second speed signals and accordingly updates the second signal profile 120 of the second sensor signals via the second rope position p2(I) within the rope range 110.

[0059] In a tenth method step 350 following the ninth method step 345, the evaluation device 40 compares the second signal profile 120 of the second sensor signal with the first reference characteristic 100, for example as part of a pattern recognition. If the second signal profile 120 substantially matches the first reference characteristic 100 with respect to the second cable region 110, the evaluation device 40 assigns the second signal profile 120 to a subsection 116 of the first reference characteristic 100. In particular, the evaluation device 40 can assign the second signal profile 120 to the first reference characteristic 100 using recurring patterns or motifs. In this case, deviations between the second signal profile 120 and the first reference characteristic 100 may exist. The deviations may be caused, for example, by wire breaks that have occurred in the meantime.

[0060] To account for rope elongation, the evaluation device 40 can apply a time-warping algorithm, in particular a dynamic time-warping algorithm, to achieve improved agreement between the second signal profile 120 of the second sensor signal relative to the rope length 110 and the first reference characteristic 100 within the framework of pattern recognition. This allows the evaluation device 40, for example, to compensate for a rope elongation of the lifting rope 20 over the service life of the lifting rope 20. Additionally or alternatively, a cross-correlation and / or a self-learning algorithm can also be used for this purpose.

[0061] By assigning the second signal curve 120 to the subsection 116 of the first reference characteristic 100, the evaluation device 40 can reliably assign the second cable position p2(I) of the second sensor signal to the respective first cable position p1(I) of the first reference characteristic 100 on the basis of the first reference characteristic 100.

[0062] In the eleventh procedural step 355 (cf. FIG 6 ), the evaluation device 40 replaces the partial section 116 of the first reference characteristic 100 by the second signal curve 120 of the second sensor signal and thereby updates the first reference characteristic 100 by the second signal curve 120 in the corresponding partial section 116 to a second reference characteristic 125.

[0063] The evaluation device 40 stores the updated reference characteristic 125 as a second reference characteristic 125 in the data memory 35 with a second time information item that essentially corresponds to the time of detection of the second sensor signal. The first reference characteristic 100 remains stored in the data memory 35 with the first time information item and is preferably not deleted.

[0064] The evaluation device 40 can automatically repeat the sixth to eleventh method steps 330 to 355 after a predefined time interval has elapsed, for example, including 1 hour to 12 hours, or after a predefined number of lifting cycles have been performed over the life of the lifting rope. In this case, the currently created second reference characteristic 125 becomes the first reference characteristic 100 in the case of repetition, which is updated based on a newly detected rope area 110. The rope area 110 newly detected in the case of repetition can be different both in its position relative to the first rope position p1(I) and in its length from the previously detected rope area 110. Thus, for example, the sixth to eleventh method steps 330 to 355 can be repeated regularly at a time interval of 1 to 12 hours over the life of the lifting rope 20.

[0065] By updating the previously created first reference characteristic 100 to the second reference characteristic 125, reliable pattern recognition is ensured during further runs of the rope section 110 as the hoist rope 20 continues to wear, and reliable assignment of the rope section 110 is enabled.

[0066] In a twelfth method step 360, the evaluation device 40 evaluates, for example, the updated reference characteristic—in the embodiment, for example, the second reference characteristic 125—against the (first) original reference characteristic 100, for example, as part of a comparison. During the evaluation, for example, at least one wire break and / or multiple wire breaks and a cable position p1(I) corresponding to the wire break can be determined. The wire break can be determined, for example, by a deviation of the amplitude of the second reference characteristic 125 from the first reference characteristic 100.

[0067] The wire break can be stored in the data memory 35 with an assignment to the first cable position p1(I) and, if desired, output by the evaluation device 40 via the data interface 45.

[0068] In particular, the evaluation device 40 can determine a number of wire breaks per reference length based on the predefined reference length. The reference length can, for example, correspond to six times the outer diameter or, for example, thirty times the outer diameter of the lifting rope 20. To this end, the evaluation device 40, for example, sums up the wire breaks and / or multiple wire breaks detected within the predefined reference length.

[0069] Based on the determined number of wire breaks per reference length, the evaluation device 40 can further determine a failure probability of the lifting rope 20 or an updated remaining service life of the lifting rope 20 based on the first and second time information.

[0070] The number of wire breaks or the respective rope position p1(I) associated with the wire breaks can be output by the evaluation device 40 as part of a rope report via the lifting rope 20 to the data interface 45, so that a manual inspection of the respective critical points can be carried out by an appropriate expert.

[0071] The evaluation device 40 can regularly repeat the sixth to twelfth method steps 330 to 360, wherein, for example, different cable sections 110 are guided past the sensor device 25 in each case, so that the corresponding second sensor signal is different in each case. The evaluation device 40 can thus update the most recent second reference characteristic 125 piece by piece over the service life of the hoisting cable 20, so that the cable aging is reflected, for example, in the updated version of the second reference characteristic 125 (cf., for example, FIG 6 ) reflects.

[0072] FIG 7 shows a second reference characteristic 125 of a ready-to-discard hoist rope 20. It is clearly visible that the most recent second reference characteristic 125 has numerous strong amplitudes in the leakage flux change D, which correlate with a large number of wire breaks.

[0073] Because with each pass through a different rope section 110, the present last reference characteristic is updated by the second signal curve 120 to the updated second reference characteristic 125 and the outdated reference characteristic 100 continues to be stored, a type of epigenetic fingerprint of the lifting rope 20 results. The reference characteristics 100 stored in the data memory 35 each represent an aging profile of the lifting rope 20.

[0074] Over time, the lifting rope 20 changes and ages. Rope anomalies, particularly wire breaks, occur. Wire breaks can accumulate, particularly in areas of the lifting rope 20 that are frequently used, until the load-bearing capacity of the lifting rope 20 is limited by the increased wire breaks, or the lifting rope 20 is no longer load-bearing. FIG 7 Such aging, particularly in the area shortly before the end 105 of the lifting rope 20, can be recognized by the significant change in the leakage flux change D compared to the first reference characteristic 100.

[0075] The epigenetic fingerprint and the first reference characteristic, each of which is further stored in the data memory 35 as part of the update of the last reference characteristic, along with the respective time information, make it possible to provide a history of the lifting rope 20, which can, on the one hand, be further evaluated by the evaluation device 40 as part of the rope report. On the other hand, inspection runs for analyzing the lifting rope 20 can be dispensed with. This eliminates the need for breaks during which the lifting system 10 is unavailable, so that the lifting system 10 is continuously available, and at the same time, an evaluation and analysis option for the lifting system 10 is available using the reference characteristics created in each case.

[0076] Due to the slow changes in the hoisting rope 20 and the deterioration of the hoisting rope due to wire breaks, the stored reference characteristics form the epigenetic fingerprint. The collection of the stored reference characteristics 100, 125 offers a good opportunity for non-destructive analysis of the hoisting rope 20 and a possibility for predicting the number of wire breaks to be expected at specific points on the hoisting rope 20 within a predefined period of time. In particular, advanced algorithms, particularly within the framework of artificial intelligence, can be used to generate a prediction of wire breaks at specific rope positions p1(I) based on the reference characteristics stored in the data memory 35.

[0077] Furthermore, a quasi two-factor identification of the rope position p1(I) of the respectively assigned second sensor signal can be enabled regularly on a routine basis or cyclically or even at specific times during the use of the lifting system 10.

[0078] In addition to the pattern recognition, as carried out in the tenth method step 350, the evaluation device 40 can additionally check via the second sensor unit 75 and the second speed signal whether the first cable position p1(I) determined for the second sensor signal is plausible.

[0079] The pattern recognition and the optionally used time-warping algorithm further have the advantage of providing a quasi-auto-calibration of the control unit 15, so that the respective first rope position p1(I) of the second sensor signal can be reliably determined even with a further elongation of the lifting rope 20. In particular, it has been shown that the combination of pattern recognition and time-warping algorithm can enable reliable detection of the respectively assigned rope area of ​​at least 98% locally and at least 99% globally based on the entire rope length of the lifting rope 20.

[0080] The control unit 15 can further be designed to provide a report on the current reference characteristic at the data interface 45 at regular intervals, whereby a prediction can also be generated based on the current rope condition of the lifting rope 20.

[0081] Because the historical data of the epigenetic fingerprint of the hoisting rope 20 continues to be stored in the data storage 35, the foundation is created on which, over the course of the rope's lifespan, detailed information can be provided to a rope inspector through the numerous stored reference characteristics. This allows, for example, trend graph projections or comparisons of local areas with wire breaks to be determined and viewed based on the numerous determined reference characteristics. This detailed information offers an additional possibility for providing a reliable prediction of the failure of the hoisting rope 20.The rope inspector can better evaluate the lifting rope 20 locally based on the reference characteristics and can, if necessary, visually inspect the critical points of the lifting rope 20 where, according to the most recent reference characteristics, numerous wire breaks are likely to be present.

[0082] FIG 8 shows a schematic representation of a lifting system 10 according to a second embodiment. FIG 9 shows a perspective view of the sensor device 25 of the FIG 8 shown lifting system 10.

[0083] The FIG 8 The second embodiment of the lifting system 10 shown essentially corresponds to that shown in FIGN 1 , 2A und 2B shown first embodiment of the lifting system 10. In the following, only the differences of the FIG 8 shown lifting system 10 compared to the one in FIGN 1 and 2A, 2B shown lifting system 10.

[0084] Deviating from the FIGN 1 and 2A, 2B , in which the rolling element 80 is designed as a speedometer wheel 81, the FIGN 8 und 9 The rolling element 80 shown is designed as a cable drum 82. The speedometer wheel 81 is omitted in the second embodiment. The speed sensor 90 is arranged, for example, on the rolling element 80 designed as a cable drum 82. The lifting cable 20 has the distance a between the contact point 85 on the cable drum 82 and the first sensor unit 70.

[0085] The FIG 3 The procedure described can also be used for the FIGN 8 und 9 The lifting system 10 shown can be used, but in FIGN 8 und 9In the third method step 315, during winding and / or unwinding of the lifting rope 20, the first speed and / or the second speed of the lifting rope 20 is determined by the speed sensor 90 on the rope drum 82. It is particularly advantageous if the lifting rope 20 is wound in only one layer on the rope drum 82. List of reference symbols

[0086] 10 Lifting system 15 Control unit 20 Lifting rope 25 Sensor device 30 Lifting device 31 Support device 33 Crane bridge 35 Data memory 40 Evaluation device 45 Data interface 50 First data connection 55 Second data connection 60 Third data connection 65 Guide roller arrangement 70 First sensor unit 75 Second sensor unit 80 Unwinding element 81 Speedometer wheel 82 Rope drum 85 Contact point 90 Speed ​​sensor 95 Start point 100 First reference characteristic 105 End 110 Rope section 111 Rope section start point 112 Rope section end point 115 Rope area 116 Section 120 Second signal curve 125 Second reference characteristic 305 first process step 310 second process step 315 third process step 320 fourth process step 325 fifth process step 330 sixth process step 335 seventh process step 340 eighth process step 345 ninth process step 350 tenth process step 355 eleventh process step 360 twelfth process step aDistance DLeakage flux change p1(I)first rope position p2(I)second rope position

Claims

1. A method for determining a rope condition of a hoisting rope (20) of a hoisting system (10), - wherein a sensor device (25) with at least a first sensor unit (70), a data memory (35), and a hoisting rope (20) of the hoisting system (10) are provided, - wherein the hoisting rope (20) is moved past the first sensor unit (70) over an available rope length, - wherein the first sensor unit (70) generates a first sensor signal, which characterizes an interaction between the first sensor unit (70) and the hoisting rope (20) moved past the first sensor unit (70), as a function of a first rope position (p1(I)) of the hoisting rope (20), - wherein a first signal curve of the first sensor signal is determined as a function of the first rope position (p1(I)) as a first reference characteristic (100) of the hoisting rope (20) and stored in the data memory (35), - wherein a rope length (110) of the lifting rope (20) which is less than or equal to the available rope length,is moved past the first sensor unit (70) after the first reference characteristic (100) of the hoisting rope (20) has been determined, - wherein the first sensor unit (70) generates a second sensor signal, which characterizes an interaction between the first sensor unit (70) and the rope section (110) moved past the first sensor unit (70), as a function of a second rope position (p2(I)) of the hoisting rope (20), - wherein a second signal profile (120) of the second sensor signal is determined as a function of the second rope position (p2(I)), - wherein the second signal profile (120) of the second sensor signal is assigned to a subsection (116) of the first reference characteristic (100), - wherein the subsection (116) of the first reference characteristic (100) assigned to the second signal profile (120) is updated by the second signal profile (120) of the second sensor signal,- wherein the updated reference characteristic is stored as a second reference characteristic (125) in the data memory (35)., 2. The method according to claim 1, - wherein the sensor device (25) has a second sensor unit (75) which is arranged at a distance from the first sensor unit (70) and rests against the hoisting rope (20), - wherein the second sensor unit (75) provides information about a first running direction of the hoisting rope (20) guided past the second sensor unit (75) over the available rope length upon determination of the first reference characteristic (100), - wherein the second sensor unit (75) provides information about a second running direction of the rope section (110) of the hoisting rope (20) guided past the second sensor unit (75), - wherein, depending on the second running direction of the rope section (110), the second sensor signal is further processed such that the first reference characteristic (100) and the second signal curve (120) are determined with the same running direction.

3. Method according to claim 2, - wherein the second sensor unit (75) has a speed sensor (90), - wherein when the lifting rope (20) moves over the available rope length, the speed sensor (90) provides a first speed signal corresponding to a first speed of the lifting rope (20) guided past the first sensor unit (70), - wherein when the lifting rope (20) moves, the speed sensor (90) provides a second speed signal corresponding to a second speed of the rope section (110) guided past the first sensor unit (70).

4. The method according to claim 3, - wherein the second sensor unit (75) has a rolling element (80) coupled to the speed sensor (90), - wherein the rolling element (80) rests on the lifting cable (20), - wherein during the movement of the lifting cable (20) the rolling element (80) rolls on the lifting cable (20) and the speed sensor (90) provides the first speed signal or the second speed signal, - wherein the first running direction is determined on the basis of the first speed signal and the second running direction is determined on the basis of the second speed signal.

5. The method according to claim 3 or claim 4, - wherein the second sensor unit (75) is arranged at a predefined distance from the first sensor unit (70), - wherein the detection of the lifting rope (20) is started with the first sensor unit (70) at a starting point (95), - wherein the first rope position (p1(I)) is determined relative to the starting point (95) as a function of the first speed signal.

6. Method according to one of claims 3 to 5, - wherein the second speed at the second cable position (p2(I)) is compared with a predefined minimum speed, - wherein if the minimum speed is exceeded by the second speed at the second cable position (p2(I)), the second sensor signal is taken into account for determining the second signal profile (120), - wherein in particular if the second speed at the second cable position (p2(I)) falls below the minimum speed, the second sensor signal is not taken into account for determining the second signal profile (120).

7. Method according to one of the preceding claims, - wherein the second signal curve (120) of the sensor signal is assigned to the first reference characteristic (100) by means of pattern recognition, in particular a cross-correlation and / or a time-warping algorithm, in particular a dynamic time-warping algorithm, and / or a self-learning algorithm.

8. Method according to one of the preceding claims, - wherein the first reference characteristic (100) is linked to a first time information item of the temporal detection of the first sensor signal and is stored with the first time information, - wherein the second reference characteristic (125) is linked to a second time information item of the temporal detection of the second sensor signal and is stored.

9. Method according to one of the preceding claims, - wherein the second reference characteristic (125) is evaluated on the basis of the first reference characteristic (100), - wherein a state of the lifting rope (20) is determined and output on the basis of a result of the evaluation.

10. The method according to one of the preceding claims, - wherein the first sensor signal and / or the second sensor signal is smoothed and / or pre-filtered before the first sensor signal and / or the second sensor signal is evaluated, - wherein in particular a Fast Fourier Transformation and / or a Wavelet Transformation, in particular a Direct Wavelet Transformation, and / or a low-pass filter is applied for filtering, - and / or wherein the first sensor signal and / or the second sensor signal is compared with a predefined minimum threshold value, - wherein the first signal curve is determined on the basis of the first sensor signal which exceeds the predefined minimum threshold value, - wherein the second signal curve is determined on the basis of the second sensor signal which exceeds the predefined minimum threshold value.

11. Method according to one of the preceding claims, - wherein the rope section (110) for determining the second signal profile (120) is determined after a predefined time interval, for example from 1 hour up to and including 12 hours, or after a predefined number of lifting cycles have been carried out.

12. Method according to one of the preceding claims, - wherein the available rope length is advanced at the first sensor unit (70) at at least one predefined minimum speed, - wherein the minimum speed is preferably at least 0.1 m / s, in particular at least 0.2 m / s.

13. Lifting system (10) for a large-scale industrial plant, in particular a rolling mill and / or a continuous casting machine and / or steelworks, - wherein the lifting system (10) is designed to carry out a method according to one of the preceding claims.