Method for operating a hoisting device and hoisting device for implementing the method

Abstract

The invention relates to a method for operating a hoisting device, wherein the hoisting device has a receiving component for receiving an object and a cable which can be wound at least partially on a winding drum, wherein the winding drum can be driven by a drive device, wherein the drive device has a first sensor, wherein a first position of the receiving component can be determined from a value detected by the first sensor, wherein a second sensor is arranged on the hoisting device, wherein a second position of the receiving component can be determined from a value detected by the second sensor, wherein a first difference of the first position and the second position is determined in a first time period, wherein a second difference of the first position and the second position is determined in a second time period, wherein an action is triggered if a numerical value of a difference between the first difference and the second difference exceeds an allowed deviation.

Description

Technical Field

[0001] The present invention relates to a method for operating a lifting device and a lifting device for implementing the method. Background Technology

[0002] It is known that a lifting device is provided for lifting an object received on a receiving component.

[0003] As the closest prior art, a lifting mechanism is known from WO 2019 / 130 425 A1. However, the cable is not wound or unwound during operation and / or the cable tension remains substantially constant during operation in this lifting mechanism.

[0004] A lifting mechanism arranged on a vehicle is known from US 2013 / 0 341 124 A1.

[0005] A method for identifying abnormal situations in elevators is known from JP 2020-7 078 A. Summary of the Invention

[0006] Therefore, the purpose of this invention is to improve the safety of lifting equipment.

[0007] According to the invention, this objective is achieved by a lifting device according to the features given in claim 10 and a method according to the features given in claim 1 or 9.

[0008] An important feature of the present invention regarding the method of operating lifting equipment is that the lifting equipment has a receiving component for receiving objects and a cable that can be at least partially wound onto a drum.

[0009] The drum can be driven by a drive unit, and in particular, it can be rotated by a drive unit.

[0010] The drive unit includes a first sensor, from which a first position of the receiving component can be determined.

[0011] A second sensor is installed on the lifting equipment, and the second position of the receiving component can be determined from the value detected by the second sensor.

[0012] Specifically, the first difference between the first position and the second position is determined within the first time period.

[0013] Specifically, the second difference between the first and second positions is determined during the second time period.

[0014] If the difference between the first and second differences exceeds the permissible deviation, an action is triggered, specifically displaying an alarm message and / or transmitting the alarm message to a computer connected to the lifting equipment, particularly the controller of the lifting equipment, via a data transmission channel.

[0015] The advantage here is that cable elongation can be monitored by two sensors. The first sensor is essentially positioned on the first end of the cable via a motor and drum, while the second sensor essentially detects the other end of the cable. Therefore, the position of the receiving component can be determined using each of the two sensors, particularly during the first time period and subsequently during the second time period.

[0016] In this way, the change in the distinction between the two determined positions due to cable elongation can be detected. The second time period is advantageously spaced far apart from the first time period. Therefore, the cable elongation is caused by the operation of the lifting equipment between the first and second time periods, i.e., by the load on the cable during operation.

[0017] In an advantageous design, the receiving component can reciprocate along a guide member formed on the lifting equipment, particularly on the support structure of the lifting equipment. The advantage here is that the receiving component can move linearly on the drum by means of cable winding or unwinding. The guide member improves the accuracy of the movement.

[0018] In an advantageous design, a first physical parameter is detected in a first region of the cable, particularly near the drum, using a first sensor. This parameter specifically detects the angular position of the rotor shaft of the motor driving the drum. A second physical parameter is detected in a second region spaced apart from the first region using a second sensor. This second physical parameter is either the distance between the second sensor, fixed to a support, and the receiving component, or it is the force transmitted through the cable. The advantage here is that the cable elongation between the two regions can be determined in a simple manner.

[0019] In an advantageous design, in a first step, the receiving component is controlled to move to a first theoretical position, specifically to a first theoretical position relative to the support of the lifting equipment. In a second step, implemented after the first step, a first difference is determined within a first time period. Subsequently, the position of the receiving component is controlled to move to at least one second theoretical position and / or another theoretical position. In a third step, the receiving component is controlled to move to the first theoretical position. In a fourth step, implemented after the third step, a second difference is determined within a second time period. The action is triggered if the difference between the first and second differences exceeds an allowable deviation. The advantage here is that the receiving component can be controlled to move to a position by means of the lifting equipment's controller and can subsequently move along a location-time curve. Controlled movement is specifically understood here as the adjustment of the actual position toward the corresponding theoretical position. For this purpose, the drive unit has an inverter that powers the motor so that the position detected by the first sensor is adjusted toward a theoretical position predetermined at the corresponding time step. Thus, the receiving component can be guided along a trajectory.

[0020] In an advantageous design, the objects received on the receiving component have the same mass in both the second and fourth steps. The advantage here is that, given the same mass, kinematic motion is performed in both measurements, allowing for very accurate comparisons.

[0021] In an advantageous design, no object is received on the receiving component in the second and fourth steps. The advantage here is that, given the same mass, kinematic motion is performed in both measurements, and therefore a very accurate comparison can be made.

[0022] An important feature of the method for operating lifting equipment is that the lifting equipment has a receiving component for receiving objects and a cable that can be at least partially wound onto a drum.

[0023] The drum can be driven by a drive unit, specifically, it can be rotated by the drive unit.

[0024] The drive unit includes a first sensor, from which a first position, specifically a position value, of the receiving component can be determined.

[0025] A second sensor is installed on the lifting equipment, and the second position of the receiving component, specifically the position value, can be determined from the value detected by the second sensor.

[0026] In the first step, during a first time period, the receiving component moves along a trajectory with a change in orbital speed, wherein the change curve of the value detected by the second sensor is stored as a first function based on the value detected by the first sensor.

[0027] In the second step, which is arranged after the first step in time, during the second time period, the receiving component moves along a trajectory with a change in orbital speed. The change curve of the value detected by the second sensor, based on the value detected by the first sensor, is stored as a second function.

[0028] In the third step, which is scheduled after the second step in terms of time, the maximum value of the convolution between the first and second functions is determined.

[0029] Specifically, the integral of the value of the difference between the first function and the second function that has shifted to the maximum value is determined, or the integral of the square of the difference between the first function and the second function that has shifted to the maximum value is determined. The advantage here is that the sensor measurements can be evaluated even during motion to determine cable elongation.

[0030] An important feature of the lifting equipment used to implement the aforementioned method is that the first sensor is an angle sensor for detecting the angular position of the rotor shaft of the motor of the drive unit.

[0031] The second sensor is designed to detect the position of the receiving component.

[0032] The advantage here is that the position of the receiving component can be determined in two different ways. Here, by means of a first sensor, the value of a first physical parameter can be detected in a first region of the cable, particularly near the drum, namely the angular position of the rotor shaft of the motor driving the drum. The value of a second physical parameter can be detected in a second region spaced apart from the first region, namely the distance between the second sensor fixed to the bracket and the receiving component, or the force transmitted through the cable. Therefore, the cable elongation that occurs over time during operation between the first and second regions can be detected.

[0033] In an advantageous design, the drive unit is designed as a motor or a geared motor, particularly a motor with a gear reducer. The advantage here is that position control is possible. Because the position of the receiving component can be adjusted to its theoretical position by means of a motor fed by a converter or an inverter.

[0034] In an advantageous design, the second sensor is arranged on the support of the lifting equipment, and in particular, the second sensor is an optical distance sensor and / or a laser distance sensor. The advantage here is that the position of the receiving component can be determined using the first sensor in a first area of ​​the cable and the second sensor in another area of ​​the cable.

[0035] In an advantageous design, the second sensor is positioned between the cable and the receiving component.

[0036] Specifically, the second sensor has a pin connected to the cable and the receiving component, and a strain gauge is connected to the pin, and / or the position of the receiving component can be determined by a quadratic integration of the value change curve detected by the second sensor. The advantage here is that the position of the receiving component can be determined using the first sensor in a first region of the cable and the second sensor in another region of the cable. However, the value change curve detected by the second sensor can be integrated over time.

[0037] In an advantageous design, the lifting equipment has rotatably supported wheels, which allow it to move on the ground of the facility. This also allows the lifting equipment to move within the facility. For example, the lifting equipment can be used as racking equipment in a facility designed as a warehouse.

[0038] In an advantageous design, a memory, particularly an RFID tag, capable of contactless writing and / or reading is arranged on the object, and RFID reading and / or writing devices are arranged on the lifting equipment, particularly on the support frame of the lifting equipment. The advantage here is that the mass of the object can be stored in the memory, particularly the RFID tag, and can be taken into account when determining the cable elongation. Therefore, even when determining the first distance, an object with a different mass can be received at the receiving component than when determining the second distance. Thus, the effect of the mass difference on the cable elongation at both determinations can be considered.

[0039] Further advantages are provided by the dependent claims. The invention is not limited to the combination of features of the claims. For those skilled in the art, particularly for purposes proposed and / or by comparison with the prior art, other reasonable combinations of features of the claims and / or individual claims and / or description features and / or drawings are possible. Attached Figure Description

[0040] The present invention will now be described in detail with reference to the schematic diagram:

[0041] exist Figure 1 The lifting device according to the present invention is schematically shown in the figure. Detailed Implementation

[0042] Here, the vertical machine shaft is arranged on a support that can move on wheels 11 on the ground of the facility.

[0043] The machine shaft has a guide member 7, along which the receiving member 8 can reciprocate. Preferably, the machine shaft is vertically oriented, allowing the receiving member 8 to rise and fall.

[0044] Object 9 is received by receiving component 8 or, in the simplest case, simply placed on receiving component 8.

[0045] The object has a contactless, particularly electromagnetic wave-based, and especially radio wave-based, memory, particularly an RFID tag. A corresponding reading device is fixed on the receiving component 8, by means of which data can be retrieved from the memory.

[0046] For example, the data also includes the mass of object 9. The reading device is connected to the electronic controller of the lifting equipment, so that the mass can be taken into account in the determination process described below.

[0047] The cable 5 is fixed to the receiving member 8 at its first end and is arranged on the drum 4 with its other end deployable.

[0048] The guide pulleys 6 arranged on the lifting equipment enable a compact structure for the lifting equipment. In particular, the drive unit of the drive drum 4 can be arranged as deep as possible, thereby minimizing the distance between the center of gravity of the lifting equipment and the ground. The drive unit has a motor fed by an inverter, which drives the drum 4 directly or through a reducer arranged in the middle.

[0049] The drive unit is fixed to the lifting equipment.

[0050] The linear motion, particularly the reciprocating motion, of the receiving component 8 is guided by the guide member 7, particularly the linear guide member.

[0051] A second sensor 2 is fixed on the lifting equipment, which determines the linear position of the receiving component 8.

[0052] The drive unit has a first sensor 1, by means of which the angular position of the rotor shaft of the motor 3 is detected.

[0053] The first sensor 1 and the second sensor 2 are connected to the controller.

[0054] Taking into account the geometry of cable 5 and drum 4, the controller also determines the linear position of receiving component 8 from the angular position of the rotor shaft of motor 3 detected by means of first sensor 1.

[0055] Therefore, the difference between the linear position determined by the value detected by the first sensor 1 and the linear position determined by the value detected by the second sensor 2 can be determined.

[0056] When the system starts running, the difference is determined for the first time and stored as the first value in the controller's non-volatile memory.

[0057] During subsequent operation, the current difference is repeatedly determined to a corresponding second value over time. When the deviation exceeds a first, unacceptable level between the first and second values, the controller displays, transmits, and / or promptly outputs an alarm message indicating an unacceptable high cable elongation. Therefore, cable 5 can be replaced before mechanical overload occurs.

[0058] A guide member 7 is fixed to the bracket 10, which serves as a receiving member 8 that can move linearly along the guide member 7 relative to the bracket 10. A second sensor 2 is also fixed to the bracket 10. Here, the second sensor 2 is arranged such that it can detect the position of the receiving member 8. Preferably, the second sensor 2 detects the position of the receiving member 8 relative to the bracket 10 without contact. In particular, the second sensor 2 is designed as an optical distance detection system, such that the distance between the second sensor 2 and the receiving member 8 is used as the position.

[0059] The angular position of the rotor shaft is detected by means of the first sensor 1, and, if necessary, the transmission ratio of the motor-driven transmission device is taken into account, as well as the radius associated with the axis of rotation of the drum 4—on which the cable 5 is wound—is taken into account, and the linear position of the receiving member 8 is determined from the detected value of this angle. The deviation between the linear positions determined by the two sensors 1 and 2 can—but is not required—be taken into account.

[0060] By repeatedly determining the difference between linear positions detected by two sensors 1 and 2 over time, changes in said difference, which are repeatedly determined over time during operation, are monitored only, and alarm signals are generated, displayed, and / or transmitted when large changes are not permitted.

[0061] The support 10 of the lifting equipment, especially the vehicle support, is preferably movable on the ground of the industrial facility by means of wheels 11 rotatably supported on the support.

[0062] A guide pulley 6 is rotatably supported on the support 10, so that the cable 5 unwound from the drum 4 is guided to the receiving component 8 via the guide pulley. Therefore, the receiving component 8 can be arranged on the side of the support 10 away from the drive unit.

[0063] Preferably, the linear position is determined repeatedly over time using two sensors, 1 and 2, in a manner as similar as possible. For this purpose, the actual position of the receiving component 8 is adjusted towards the theoretical position by the drive mechanism, wherein the value detected by the first sensor 1 is used to determine the actual position. After reaching the theoretical position, particularly after an additional period of time following a possible decrease in vibration or movement of the receiving component 8, the current difference is determined using the linear position determined by the first sensor 1 or by the second sensor 2, and this difference is then monitored to ensure that there is no unacceptably high degree of deviation.

[0064] In the repeated determination of the linear position over time, preferably no object 9 is received on the receiving component, such that the mass of the receiving component 8 is the same in each determination of the difference. Alternatively, although object 9 is received on the receiving component 8, the mass of object 9 together with the receiving component 8 is always the same. Therefore, the mass-related portion of the cable elongation remains constant, and the determined difference is caused by cable elongation related to aging or overload.

[0065] The receiving component 8 is also always understood as the receiving unit.

[0066] In another embodiment of the invention, during a first time period, the difference is stored as a function of a linear position determined by a value detected by the first sensor 1, and during a second time period spaced temporally from the first time period, the updated difference is determined as a function of the linear position determined by the value detected by the first sensor 1. If the updated difference deviates unacceptably from the difference determined for the first time period, an alarm message is displayed, transmitted, and / or output promptly, indicating an unacceptably high cable elongation. Therefore, the cable 5 can be replaced in time before a mechanical overload occurs.

[0067] In other embodiments of the invention, the surface region, particularly the metal surface region, reflects radiation emitted by the second sensor, so that the sensor signal generated by the second sensor includes information about the spacing between the surface region and the receiving member 8.

[0068] In other embodiments of the invention, the receiving component 8 is constructed in a multi-body, i.e., multi-piece manner.

[0069] In other embodiments of the invention, the controller having the inverter is designed as an integrated device.

[0070] In another embodiment of the invention, the second sensor 2 is not fixed to the bracket, but is designed as a load-measuring pin with a strain gauge, wherein the load-measuring pin is arranged between the cable 5 and the receiving member 8. Here, a first region of the load-measuring pin is connected to the receiving member 8, and a second region of the load-measuring pin, spaced apart from the first region, is connected to the cable 5. Thus, the force acting on the receiving member can be detected by means of the strain gauge, wherein the corresponding change curve of the linear position of the receiving member can be determined by double time integration of the force change curve.

[0071] In another embodiment of the invention, the driving device induces the same kinematic process in the second time period as in the first time period prior to the second time period. In each of the two kinematic processes, the same mass of the object 9 is received on the receiving member 8. During the process in the first time period, a curve showing the change of linear position based on the value detected by the second sensor 2, according to the value detected by the first sensor 1, is stored as a first function. Accordingly, a second function is formed during the second time period. The maximum value of the convolution of the first function and the second function is then determined. The maximum value represents the movement of the second function relative to the first function. Then, the integral of the value of the difference between the first function and the second function in a region of the linear position is determined, or the integral of the square of the difference between the first function and the second function is determined.

[0072] If the integral value determined in the first time period has an unacceptably high deviation from the integral value determined in the second time period, an alarm message is displayed, transmitted, and / or output in a timely manner, indicating the unacceptable high cable elongation.

[0073] If the maximum value determined in the first time period has an unacceptably high deviation from the maximum value determined in the second time period, an alarm message is displayed, transmitted, and / or output in a timely manner, indicating the unacceptable high cable elongation.

[0074] List of reference numerals in the attached diagram:

[0075] 1. The first sensor, especially the first position detection sensor

[0076] 2. Second sensor, especially second position detection sensor

[0077] 3 motors

[0078] 4. Roll

[0079] 5. Cables

[0080] 6. Steering pulley

[0081] 7. Guide components

[0082] 8 Receiving components

[0083] 9 objects

[0084] 10. Brackets, especially vehicle brackets.

[0085] 11 wheels

Claims

1. A method for operating lifting equipment, wherein, The lifting equipment has a receiving component for receiving an object and a cable that can be at least partially wound onto a drum, the drum being driven by a drive unit having a first sensor, from which a first position of the receiving component can be determined. Its features are, A second sensor is installed on the lifting equipment, and the second position of the receiving component can be determined from the value detected by the second sensor. In the first time period, determine the first difference between the first and second positions; in the second time period, determine the second difference between the first and second positions. If the difference between the first and second differences exceeds an allowable deviation, an action is triggered, causing the receiving component to reciprocate along a guide member constructed on the lifting equipment. The angular position of the rotor shaft of the drive drum motor is detected by a first sensor, and the value of a second physical parameter is detected separately from the drum by a second sensor. The second physical parameter is the distance between the second sensor, fixed to the support, and the surface area of ​​the receiving component, where the surface area reflects radiation emitted by the second sensor. Alternatively, the second physical parameter is the force transmitted through the cable. In the first step, the receiving component is controlled to move to a first theoretical position relative to the support of the lifting equipment. In the second step, implemented after the first step, a first difference is determined within a first time period. Subsequently, the position control of the receiving component is moved to at least one second theoretical position and / or another theoretical position. In the third step, the receiving component is moved to the first theoretical position. In the fourth step, implemented after the third step, a second difference is determined within a second time period. Subsequently, if the numerical difference between the first difference and the second difference exceeds an allowable deviation, the action is triggered. In the second and fourth steps, the objects received on the receiving component have the same mass, or no objects are received on the receiving component in the second and fourth steps.

2. The method according to claim 1, characterized in that, The receiving component can reciprocate according to the rotation direction of the drum driven by the drive unit, wherein the cable is wound more and more onto the drum during the upward movement, and the cable is unwound more and more from the drum during the return movement.

3. The method according to any one of the preceding claims, characterized in that, Using a first sensor, the value of a first physical parameter is detected in a first region of the cable, and using a second sensor, the value of a second physical parameter is detected in a second region separated from the first region.

4. The method according to claim 1, characterized in that, If the difference between the first and second differences exceeds the permissible deviation, an alarm message is displayed and / or transmitted to a computer connected to the controller of the lifting equipment via a data transmission channel, wherein the radiation is light, ultrasonic, or radar radiation.

5. The method according to claim 3, characterized in that, The first physical parameter is the angular position of the rotor shaft of the motor that drives the drum of the drive unit.

6. A method for operating lifting equipment, wherein, The lifting equipment has a receiving component for receiving an object and a cable that can be at least partially wound onto a drum, the drum being driven by a drive unit having a first sensor, from which a first position of the receiving component can be determined. Its features are, A second sensor is installed on the lifting equipment, and the second position of the receiving component can be determined from the value detected by the second sensor. In the first step, during a first time period, the receiving component is moved along a trajectory with a change in orbital speed, and the curve showing the change in value detected by the second sensor as a function of the value detected by the first sensor is stored. In the second step, which follows the first step in time, during the second time period, the receiving component moves again along the trajectory with the orbital speed change curve, and the curve showing the change of the value detected by the second sensor with the value detected by the first sensor is stored as a second function. In the third step, which follows the second step in time, the maximum value of the convolution of the first function and the second function is determined, and the integral of the difference between the first function and the second function shifted by the maximum value is determined, or the integral of the square of the difference between the first function and the second function shifted by the maximum value is determined; the receiving component can reciprocate along a guide member constructed on the lifting equipment; the angular position of the rotor shaft of the motor of the drive drum of the drive device is detected by means of a first sensor, and the value of a second physical parameter is detected by means of a second sensor spaced apart from the drum; the second physical parameter is the distance between the second sensor fixed on the bracket and the surface area of ​​the receiving component, wherein the surface area reflects radiation emitted by the second sensor, or the second physical parameter is the force transmitted by the cable, wherein in the first In the steps, the receiving component is controlled to move to a first theoretical position based on the support of the lifting equipment. In the second step, which is implemented after the first step, a first difference is determined within a first time period. Subsequently, the position of the receiving component is controlled to move to at least one second theoretical position and / or another theoretical position. In the third step, the receiving component is controlled to move to the first theoretical position. In the fourth step, which is implemented after the third step, a second difference is determined within a second time period. Subsequently, if the value of the difference between the first difference and the second difference exceeds the allowable deviation level, the action is triggered. In the second and fourth steps, the objects received on the receiving component have the same mass, or no objects are received on the receiving component in the second and fourth steps.

7. A lifting device for implementing the method according to any one of the preceding claims, characterized in that, The first sensor is an angle sensor used to detect the angular position of the rotor shaft of the motor of the drive unit, and the second sensor is designed to detect the position of the receiving component.

8. The lifting equipment according to claim 7, characterized in that, The drive unit is designed as an electric motor.

9. The lifting equipment according to claim 7, characterized in that, The drive unit is designed as a geared motor.

10. The lifting equipment according to any one of claims 7 to 9, characterized in that, The second sensor is mounted on the support frame of the lifting equipment. This second sensor is an optical distance sensor and / or a laser distance sensor. or A second sensor is arranged between the cable and the receiving component, wherein the second sensor has a pin that connects to both the cable and the receiving component, a strain gauge is connected to the pin, and / or the position of the receiving component can be determined by the quadratic integration of the value change curve detected by the second sensor.

11. The lifting equipment according to any one of claims 7 to 9, characterized in that, The lifting equipment has wheels that are supported in a rotatable manner, and the lifting equipment can move on the ground of the facility by means of the wheels.

12. The lifting equipment according to any one of claims 7 to 9, characterized in that, RFID tags capable of being written to and / or read without contact are placed on objects, and RFID reading and / or writing devices are placed on lifting equipment.

13. The lifting equipment according to claim 9, characterized in that, A geared motor is a motor with a speed reducer.

Images