Method for operating a conveyor system, control unit for a conveyor system, and conveyor system

Abstract

The present invention relates to a method and a control unit for operating a conveyor means, in particular a hoist, a crane, a continuous conveyor or the like, the conveyor means comprising a drive unit (21) and a control unit (20) for controlling the drive unit, the drive unit comprising at least two drives (43, 44) which are controlled by a control device (22) of the control unit, rotary encoders (25, 38) of the control unit being connected to shafts (29, 42) of the drive units of the conveyor means respectively assigned to the drives, for recording the rotations of the shafts and transmitting rotation angle signals and / or rotation speed signals by means of the encoder devices (26, 39) of the corresponding rotary encoders to the control device for controlling the drives, the control device determining the corresponding rotation speed of the shaft, comparing it with a reference rotation speed and controlling the drives depending on the comparison.

Description

Technical Field

[0001] The present invention relates to a control unit for conveyor means and a method for operating conveyor means, particularly hoists, cranes, continuous conveyors, etc., wherein the conveyor means comprises a drive unit and a control unit for controlling the drive unit, the drive unit comprises at least two drive devices, the drive devices are controlled by a control device of the control unit, a rotary encoder of the control unit is connected to a shaft of the drive unit of the conveyor means respectively assigned to the drive devices, records the rotation of the shaft, and in order to control the drive devices, a rotation angle signal and / or a rotation speed signal is transmitted to the control device by an encoder device of the corresponding rotary encoder.

Background Art

[0002] Such control units and methods are well known from the prior art and are essentially used to record the position and rotational speed of a shaft. The rotary encoder of the control unit comprises at least one shaft that can be connected to a machine or is directly arranged on the shaft of the machine. Furthermore, the rotary encoder comprises a mechanical, optical or magnetic encoder device or recording element. The encoder device can form, for example, an incremental encoder or an absolute encoder. In a mechanical embodiment, the encoder device can also be a switch or a counter. The encoder device can obtain a signal such as a rotation angle signal or a rotation speed angle with respect to the rotation of the shaft. From these signals, the rotation angle position of the shaft or the rotation speed of the shaft can be determined by a control device of the control unit to which the rotary encoder is connected via a signal line.

[0003] Rotary encoders are used in or on conveyor systems, particularly hoists with rope hoists, cranes, jibs, clubs, winches, etc., and on or on conveyor belts, and are subjected to large loads during operation. Therefore, the casing of a rotary encoder is generally made of metal, and the rotary encoder is relatively elastic against mechanical and thermal stress. To transmit the encoder signal to the control device of the conveyor system, the rotary encoder may have a signal output device, which preprocesses the signal for transmission to the control device. This is particularly necessary for use with fiber optic cables.

[0004] Rotary encoders on a conveyor system primarily serve to obtain specific operating parameters of the conveyor system, such as the rotational speed of the rope drum or the motor or electric motor that drives the rope drum. Thus, a conveyor system is known in which a drive unit is formed having a rope for lifting a bearing load, a rope drum, an electric motor, and a transmission that switches between these. Rotary encoders can be placed on the shafts of the electric motors and / or the rope drums, respectively, to transmit rotational angle signals and / or rotational speed signals to the control device of the conveyor system in order to control the assigned electric motor. Therefore, a conveyor system generally has several such drive units or electric motors, which means that several rotary encoders are mounted on the hoist. As a result, the control device works in conjunction with the rotary encoders to form a control unit, which adjusts the drive units according to the bearing load. The control device receives information from each rotary encoder regarding the rotational speed of each drive unit or shaft of the power transmission driven by the electric motor. For example, with large bearing loads, the control device adjusts the rotational motor speed of each electric motor so that it does not exceed a certain speed when lifting or lowering the bearing load, or exceed the rotational speed of the rope drum. When the bearing load is relatively small, such as in an empty container, the bearing load can be increased at a higher speed, i.e., at a higher rotational motor speed. Each electric motor is always adjusted separately from one another according to its respective rotational speed. Therefore, the adjustment of the drive unit by the control device is always aimed at matching the performance of the drive unit to the bearing load so that the bearing load can be transported as quickly as possible by the conveyor or hoist. In addition to adjusting such drive devices on a hoist, the control unit can also be installed on other conveyor means such as a continuous conveyor or a belt conveyor. In this case as well, multiple drive devices are formally used to transport the load or applied load. [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In hoists known from the prior art, the control device is generally located within the control panel of the conveyor system and can be a programmable logic controller (PLC), which is programmable via an external programming device such as a standardized computer. The programmable logic controller, or rather the control device, incorporates a processing element that processes the rotation angle signal and / or rotation speed signal from the conveyor system's rotary encoder and converts them so that the drive unit can be controlled according to the rotation speed via the control device. The drawback here is that an individual program for the programmable logic controller is always required. This program for the control device generally needs to take general safety regulations into account, and as a result, the control device thus implemented must be individually controlled for further safety reasons. Furthermore, the conveyor speed is limited by the rules of the individual drive unit having the programmable logic controller or control device.

[0006] Therefore, the object of the present invention is to propose a method for operating a conveyor system that can operate the conveyor system more efficiently, a control unit, and a conveyor system. [Means for solving the problem]

[0007] The object of the present invention is achieved by a method having the features of claim 1, a control unit having the features of claim 16, and a conveyor means having the features of claim 20.

[0008] In the method according to the present invention for operating conveyor means, particularly hoists, cranes, continuous conveyors, etc., the conveyor means comprises a drive unit and a control unit for controlling the drive unit, the drive unit comprises at least two drive devices, the drive devices are controlled by a control device of the control unit, the rotary encoders of the control unit are connected to the shafts of the drive units of the conveyor means, each assigned to the drive device, and record the rotation of the shafts and transmit rotation angle signals and / or rotation speed signals to the control device by the encoder devices of the corresponding rotary encoders in order to control the drive devices, the control device determines the corresponding rotation speed of the shafts, compares it with a reference rotation speed, and controls the drive devices in accordance with the comparison.

[0009] In the method according to the present invention, at least one rotary encoder is provided in each drive unit or power transmission, along with one or more shafts on at least one shaft, and is used to determine the rotational speed of the shaft of the power transmission of the rotary encoder, and therefore is used in the drive unit. The corresponding rotary encoder transmits the rotation angle signal and / or rotational speed signal of the encoder device of the rotary encoder to the control device. For this purpose, the rotary encoder can process the rotation angle signal and / or rotational speed signal itself and can also transmit a value including a rotational speed value or rotational speed information to the control device. Thus, the control device can determine the corresponding rotational speed of the shaft and therefore of the individual drive units. The control device further compares the corresponding rotational speeds of the shaft and the drive units and compares them to a reference rotational speed. As a result, the control device can detect the difference rotational speed with respect to the rotational speed of each drive unit by reference to the reference rotational speed. The control device controls each drive unit in accordance with the comparison of the detected rotational speed of the drive unit on the shaft with respect to the reference rotational speed. This makes it possible to synchronize all drive units of the drive unit according to the reference rotational speed. Therefore, differences in rotational speed between drive units that could occur when each drive unit is individually adjusted according to the rotational speed of the assigned rotary encoder are avoided. Overall, since the drive unit with the lowest rotational speed in the drive unit no longer determines the maximum conveyor speed, higher conveyor speeds can also be achieved. The reference rotational speed can be set to, for example, the drive unit with the highest rotational speed, which means that the rotational speeds of the remaining drive units are adjusted by the control unit to the highest possible rotational speed.

[0010] As a result, the control unit can determine a reference rotational speed according to the rotation angle signal and / or rotational speed signal of one of the rotary encoders, and the control unit can adjust each drive unit according to the reference rotational speed. The control unit can simultaneously record all rotational speeds of the shaft or power transmission via their respective assigned rotary encoders and define, for example, the highest rotational speed as the reference rotational speed to which the rotational speeds of the remaining drive units are each adjusted. As a result, all drive units can operate at nearly identical synchronous rotational speeds. It can also prevent potential slippage between drive units that could lead to performance degradation.

[0011] If the control device can determine the corresponding acceleration of the shaft and compare it to a reference acceleration, it is advantageous that the control device can adjust each drive unit according to the reference acceleration. The control device can determine or adjust the acceleration in relation to the time period by rotation angle signal and / or rotation speed signal. This also allows the acceleration of the corresponding shaft of the drive unit to be adjusted according to the reference acceleration. In this case as well, the control device can define or select the reference acceleration according to one of the measured accelerations of the shaft. By controlling the drive unit according to the reference acceleration, the rotation speed of the drive unit or shaft can be synchronized more precisely.

[0012] It is particularly advantageous if the control unit can record load signals from load sensors of sensor devices assigned to each drive unit and compare them to a reference load, thereby allowing the control unit to adjust each drive unit according to the reference load. A load sensor that detects the load acting on the drive unit or assigned shaft and transmits a load signal to the control unit can be assigned to each drive unit or power transmission. In this case, the control unit can compare the corresponding load signals with each other and correlate them to the reference load. One of the load signals can also be designated as the reference load. Then, all loads can be adjusted by the control unit according to the reference load, for example, by adjusting the rotational speed of each drive unit.

[0013] The control device can store range parameters for rotational speed, acceleration, and / or load, and the range parameters can limit the reference rotational speed, reference acceleration, and / or reference load. Therefore, the control device does not need to take into account the rotational speed, acceleration, and / or load detected via the rotary encoder and / or load sensor of the drive unit or power transmission as the reference rotational speed, reference acceleration, and / or reference load for adjusting the drive unit. The range parameters can be stored in the control device, for example, so that all drive units can be adjusted with respect to their rotational speed, acceleration, and / or load within the range of the range parameters while the conveyor means is in operation. Nevertheless, in this case, the range parameters or ranges can be selected close enough that the drive units can be synchronized, so that each drive unit can be synchronized.

[0014] With a rotary encoder, load signals can be recorded by load sensors assigned to the drive unit, and the rotary encoder can determine load-dependent variables in response to the rotation angle signal and / or rotation speed signal and the load signal, and transmit them to a control unit to control the unit. This allows for the merging of the rotation angle signal and / or rotation speed signal of the rotary encoder's encoder device with the load signal of a load sensor, which is normally expected to occur within the control unit, within the rotary encoder itself. As a result, each rotary encoder can receive load signals from its assigned load sensor, process these through data processing related to the rotation angle signal and / or rotation speed signal of the respective rotary encoder, generate load-dependent variables, and transmit them to the control unit. These load-dependent variables can be further processed by the control unit to directly control each drive unit without requiring a specific individual program in the control unit to merge the corresponding signals. The rotary encoders installed on the conveyor system may be standardized rotary encoders, which only require one-time control for safety reasons related to signal processing or programming. Therefore, the programmable logic controller of the control unit can be programmed with significantly less effort. The signal processing in each rotary encoder eliminates the need for the control unit to perform this signal processing, thus, overall, enabling a faster processing speed for the control unit. Load-dependent variables can also be transmitted as signals to the control unit by each rotary encoder, and these signals differ from the rotation angle signal and / or rotation speed signal in that they contain information directly related to the applied load.

[0015] The control device can limit the rotational speed of the drive unit or turn off the drive unit when the load exceeds a certain limit. This ensures that the conveyor does not exceed a maximum allowable rotational speed, such as a threshold rotational speed, relative to the load being conveyed. Therefore, loads that are too large for the conveyor cannot be conveyed using the conveyor device.

[0016] Load signals can be recorded for the work point, rope load, and / or winding load by multiple load sensors assigned to each drive unit. These load sensors can be placed, for example, on the rope drum of the hoist, or even to measure the winding speed to derive the winding load. Furthermore, load cases can be measured using load sensors related to mechanical interference such as shaft breakage or movement of the hoist's cantilever. Thus, multiple load sensors can be placed on the hoist or conveyor to measure various load cases.

[0017] A load plug gauge or load measuring cell can be used as a load sensor. If a drive unit or multiple drive devices hold the rope, for example, two load signals may be recorded for each rope to achieve load sensor redundancy.

[0018] When load signals are recorded by load sensors assigned to each drive unit by the safety elements of each rotary encoder, it is particularly advantageous that the safety elements can determine the load-dependent maximum threshold rotational speed in response to the rotation angle signal and / or rotation speed signal and load signal, and transmit these to the control unit for controlling the drive unit. The fact that each threshold rotational speed is calculated by the safety elements of the rotary encoder significantly reduces the programming effort and error tendency of the control unit. The control unit can then directly adopt the maximum threshold rotational speed value from the rotary encoder and further process this value to control the drive unit. Since the rotary encoder can process these signals, the control unit no longer needs to be adjusted to special types of rotation angle or rotation speed signals or load signals, and no longer needs to guarantee safety, thus significantly reducing the effort required to deploy the conveyor. Therefore, each rotary encoder can be a self-contained rotary encoder system requiring only one-off safety checks.

[0019] The safety element can determine a function of threshold rotational speed from the rotation angle signal and / or rotational speed signal and load signal. The mathematical regulation function of the threshold rotational speed can be adjusted, for example, to match the performance-specific curve of the electric motor of the drive unit. The threshold rotational speed can then be determined in a way that is infinitely variable and conforms to the maximum possible performance of the electric motor. This allows for a favorable increase in the conveyor speed of the drive unit or drive mechanism.

[0020] The safety element can correct the load signal from the load sensor while taking into account the acceleration of the applied load on the conveyor system. Therefore, the safety element can, for example, take into account the acceleration of the rope, whose own weight may be relevant to determining the threshold rotational speed, and the acceleration of the applied load when the drive system raises or lowers the applied load. Furthermore, the safety element can determine the net load and / or total load. In addition, the safety element may be intended to calculate the sum and difference from individual load values.

[0021] The safety element can determine the eccentricity of the applied load or bearing load on the hoist from the load signal. For example, if several load sensors are provided or the drive unit has several ropes for lifting the bearing load, the load distribution on the ropes or load sensors can be determined. Depending on the type of bearing load, for example, a container or different objects with an unevenly distributed load, a larger load can be measured on one rope facing different ropes. The safety element can then take this load distribution into account and adjust the threshold rotation speed of each drive unit for the rope according to the measured maximum load.

[0022] The control unit can transmit a status signal containing information about the operation type of the drive unit to a safety element, which can then take the status signal into account when determining the load-dependent threshold rotational speed. The operation type can be, for example, lifting or lowering a bearing load exceeding a threshold load or overload, slack rope, free running, or high-speed driving of the respective drive unit. For example, the load-dependent threshold rotational speed can be completely ignored during free running if the load derived from the rope weight is particularly low.

[0023] The safety element can determine the operation type of the drive unit—lifting, lowering, overload, slack rope, or free running—in response to the rotation angle signal and / or rotation speed signal and / or load signal, and can transmit this information to the control unit. Accordingly, the safety element can determine the operation type itself by evaluating the corresponding signal and deriving possible operation types from it. For this purpose, a specific value range or signal pattern can be stored in the safety element. This allows the operation type to be determined by comparison. Once the control unit communicates the operation type to the safety element, it can perform a validity comparison. If the results do not match, for example, the control unit can shut down the corresponding drive unit or the entire drive mechanism.

[0024] A rotary encoder can record the switch signals of a sensor device's terminal switch, and the rotary encoder can determine the relative position of the driving load on the conveyor means according to the switch signals. Safety elements can take the switch signals into account when determining the load-dependent threshold rotational speed. For example, the relative position of the cantilever's claw of a hoist can be determined via the terminal switch. Thus, in safety-related areas, for example, when the track is located below the hoist, it is possible to ensure that the applied load or bearing load moves at a lower threshold rotational speed. Furthermore, the terminal switch can determine the possible length of the rope at a specific position on the hoist and can be taken into consideration when determining the threshold rotational speed.

[0025] The safety factor can assign a maximum threshold load to each operation type or relative position. Based on the corresponding maximum threshold load, the threshold rotational speed depending on it can be determined in turn. The maximum threshold load can be defined especially considering the safety aspect and is stored in the safety factor for the corresponding operation type or relative position. In this situation, it may also be intended that the load signal of the load sensor is not considered when the corresponding maximum threshold load is reached.

[0026] When the load signal is recorded by the counter of the rotary encoder, it is particularly advantageous if this counter can store the rotation angle signal and / or the rotational speed signal and the load signal during the operation time, determine the damage value depending on the load, and transmit it to the control element for controlling the drive device. Then, the counter can store the individual or all signals, the load signal, the rotation angle signal and / or the rotational speed signal during the operation time and sum them up together. The counter element can detect the total load or load set corresponding to the damage value depending on the load. Therefore, for example, each time the bearing load is lifted, the fatigue of the parts progresses with the hoist, and when a specific number of values or the total of the moved bearing loads is reached, the parts must be inspected or replaced for safety reasons.

[0027] The counter can determine the time point when the drive device or other parts are worn from the stored signals. At this time point, inspection or service including replacement of parts is necessary if required. The counter can inform the time point or the imminent arrival of that time point itself, and by transmitting the damage value to the control device, the operation of the drive device or the drive unit can be switched off or the performance can be reduced.

[0028] The load signal can also be recorded by an evaluation element of the rotary encoder, and the evaluation element can determine the weight of the working load in the conveyor means from the load signal and transmit it to the control device. Therefore, the evaluation element can determine the net weight by the load signal of the evaluation element used for measuring the weight of the working load or the bearing load. It is no longer necessary to use a load sensor that only functions for weighing the bearing load and determining the load on the components of the conveyor means. As a result, the load sensor used for weighing in another way becomes unnecessary.

[0029] Also, another rotary encoder of the control unit can be connected to another shaft of the drive device and can be intended to record the rotation of the other shaft. The rotational speed and / or load signal can be recorded by the other rotary encoder, and the other rotary encoder can determine another load-dependent variable according to another rotation angle signal and / or another rotational speed signal and the load signal and transmit them to the control device for controlling the drive device. The drive unit can include several rope rolls, an electric motor, and a transmission that play a role in transporting individual working loads. The control device receives the latest load-dependent variable from the corresponding rotary encoder, and the variable can be used by the control device to control the entire drive unit or individual motors and / or drive devices of the drive unit.

[0030] The control unit for conveyor means, especially for hoists, cranes, continuous conveyors, etc., includes a control device and at least two rotary encoders. The rotary encoders can be connected to the shafts of the conveyor means assigned to each drive device of the drive unit to record the rotation of the corresponding shafts. The rotary encoders are encoder devices that output a rotation angle signal and / or a rotational speed signal to the control device to control the drive unit. The corresponding rotational speed of the shaft can be determined by the control device and compared with the reference rotational speed, and the drive device can be controlled by the control device according to the comparison. For details of the advantages of the control unit according to the present invention, refer to the description of the advantages of the method according to the present invention.

[0031] Advantageously, one of the rotary encoders can be equipped with a control unit. In this case, the control unit requires only one control unit, which is built into one of the rotary encoders. The remaining rotary encoders can be directly connected to the rotary encoders that make up the control unit. Furthermore, the rotation angle signals and / or rotation speed signals of the remaining rotary encoders can be directly transmitted to the control unit of one rotary encoder, and the control unit can further process the signals to control the drive unit or individual drive devices without requiring them to be individually programmed in a specific way to merge the corresponding signals. The rotary encoders installed on the conveyor system can be standardized rotary encoders that require only one-off checks for safety reasons with respect to signal processing or programming. The programmable logic controller of the control unit can be programmed with significantly less effort. Also, signal processing in the rotary encoders allows for a faster overall processing speed of the control unit, as the control unit no longer needs to perform signal processing. Load-dependent variables can also be transmitted to the control unit of one rotary encoder as signals from load sensors, which differ from the rotation angle signals and / or rotation speed signals in that relevant information about the applied load can be directly included in the signal. All rotary encoders in the control unit can be easily connected to the control unit via a fieldbus interface for exchanging data via the fieldbus. Generally, it is also possible to position the control unit separately from the rotary encoders.

[0032] The rotary encoder may also have a switch output that exceeds or falls below a parameterizable load-dependent output value. A safety relay or a semiconductor relay may be attached to the switch output. The parameterizable output value may be a rotational speed value, a rotational speed value that is too high or too low, a rotational angle value, or a rotational speed derivative value.

[0033] A rotary encoder can be an incremental encoder and / or an absolute encoder. An incremental encoder can be advantageously used, for example, when the rotary encoder is located on a drive unit or on an electric motor of a drive unit. Incremental signals and / or absolute signals can be processed even more advantageously when the rotary encoder is located, for example, on a rope drum of a drive unit. The encoder device can output these signals in parallel with rotation angle signals and / or rotation speed signals or load-dependent variables. The absolute signal can be a signal known as a single-turn signal referring to a single rotation of the shaft, or a multi-turn signal referring to multiple rotations of the shaft. Furthermore, the rotary encoder may have digital or analog outputs for absolute or incremental signals. The analog output can be a power output or a voltage output.

[0034] Furthermore, the control unit may be equipped with four or more rotary encoders. For example, the control unit may consist of two incremental encoders and two absolute encoders, which are assigned to or connected to two power transmissions. However, if the conveying means is a continuous conveyor such as a belt conveyor with many drive units installed, the number of rotary encoders may be much larger.

[0035] Further advantageous embodiments of the control unit can be obtained from the description of the features of the dependent claims relating to the apparatus of claim 16.

[0036] The conveyor means according to the present invention, particularly hoists, cranes, etc., comprises a control unit according to the present invention and a drive unit having at least two electric motors, a transmission, and two rope drums. [Brief explanation of the drawing]

[0037] The present invention will be described in more detail below with reference to the attached drawings. [Figure 1] Figure 1 is a schematic diagram of the configuration of a conventional control unit. [Figure 2] Figure 2 is a schematic diagram of the control unit configuration. [Figure 3] Figure 3 is a simplified diagram of the drive unit. [Modes for carrying out the invention]

[0038] Figure 1 shows a control unit 10 according to the prior art, along with a drive unit 11 having a drive mechanism (not shown). The control unit 10 comprises a control device 12, a sensor device 13 having a load sensor (not shown), a programming device 14, and a rotary encoder 15. Furthermore, the rotary encoder 15 connected to the drive mechanism of the drive unit 11 can be connected to the control device 12. The control device 12 includes a processing element 16 that can receive load signals from the load sensor via the sensor device 13. Furthermore, the processing element 16 can receive rotation angle signals and / or rotation speed signals from the encoder device 17 of the rotary encoder 15. In this case, the rotary encoder 15 is connected to the drive unit 11 via a shaft 18, and the drive unit 11 comprises a rope drum (not shown), an electric motor (not shown), and a transmission (not shown). The control unit 10 and the drive unit 11 are part of a hoist or crane, and neither is shown in this example.

[0039] The processing element 16 calculates load-dependent variables, such as the maximum threshold rotational speed, from the load signal of the sensor device 13 and the rotation angle signal and / or rotational speed signal of the rotary encoder 15, and transmits a control signal based on these variables to the control unit 11 and receives a status signal from the drive unit 11. The control device 12 is programmable by a programming device 14, which may be a computer (not shown). Furthermore, the control unit 10 includes a counter 19 that can sum the load signals of the sensor device 13 present in the processing device 16 during operation, and thus determine the total load. This yields a damage value that can be returned from the counter 19 to the processing device 16, for example, in the form of a switch-off signal.

[0040] Figure 2 is a simplified diagram showing a control unit 20 that works in conjunction with the drive unit 21. The control unit 20 comprises a control device 22, a sensor device 23 having load sensors 36 and 37, a programming device 24, and rotary encoders 25 and 38. The rotary encoders 25 and 38 each comprise encoder devices 26 and 39, safety elements 27 and 40, and counters 28 and 41, respectively, and are connected to the drive devices 43 and 44 of the drive unit 21 via shafts 29 and 42, respectively.

[0041] When the drive unit 21 or the drive devices 43 and 44 are operated, the rotary encoder 25 connected to the drive device 43 and the rotary encoder 38 connected to the drive device 44 detect the corresponding rotation angle signal and / or rotation speed signal via the corresponding encoder devices 26 and 39, and transmit these to the control device 22. Furthermore, the rotary encoders 25 and 38 each receive load signals from the sensor device 22 or the respective load sensors 36 and 37, and the safety devices 27 and 40 each determine load-dependent variables such as the maximum threshold rotation speed for the respective drive devices 43 and 44 from their respective rotation angle signals and / or rotation speed signals and load signals, and the maximum threshold rotation speed is transmitted to the control device 22 to control the drive unit 21 or the drive devices 43 and 44, respectively.

[0042] Furthermore, each counter 28 and 41 sums the corresponding load signals during the operating time of the drive units 43 and 44 and transmits the damage value to the control unit 22. When a certain damage value is reached, the control unit 22 can, for example, turn off the drive unit. The control unit 22 is programmable by the programming device 24. The control unit 22 can also directly receive and further process load signals from the sensor device 23. The control unit 22 receives status signals from the drive unit 21 or the drive units 43 and 44 and transmits them to the corresponding rotary encoders 25 and 38. The status signals relate to the operation type of the drive units 43 and 44, such as bearing load or raising and lowering of slack rope.

[0043] The rotation angle signals and / or rotation speed signals transmitted to the control unit 22 by the rotary encoders 25 and 38 are further processed by the control unit so that the corresponding rotation speeds of the drive units 43 and 44 are determined for each drive unit 43 and 44. The control unit 22 compares the corresponding rotation speeds to a reference rotation speed and can store this in the form of a range parameter. Furthermore, it may be intended that one of the two rotation speeds from the control unit 22 be designated as the reference rotation speed. It is essential that the control unit 22 controls the drive units 43 and 44 in accordance with the comparison of the corresponding rotation speeds with the reference rotation speed. For example, if the drive units 43 and 44 are adjusted using the control unit 22 due to the rotation speeds of the drive units 43 and 44 provided by the corresponding rotation angle signals and / or rotation speed signals of the rotary encoders 25 and 38, the control unit 22 can define the rotation speed assigned to the drive unit 43 as the reference rotation speed. Here, the rotation speed is compared to the reference rotation speed, the rotation speed, and consequently the same reference rotation speed in the drive unit 43. The rotational speed of the drive unit 44 is adjusted according to the reference rotational speed. Furthermore, the control device may be intended to make auxiliary adjustments according to acceleration and / or load.

[0044] Figure 3 is a schematic diagram of a drive unit 21 having rotary encoders 25 and 38. The rotary encoders 25 and 38 are connected to rope drums 30 and 45 via ropes 31 and 46, respectively, and via shafts 29 and 42, respectively, meaning that the rotary encoders 25 and 38 can detect the rotation angle and / or rotational speed of the rope drums 30 and 45, respectively. The rope drums 30 and 45 each have rope break sections 32 and 47, respectively, which are connected to electric motors 34 and 48, respectively, and drive the rope drums 40 and 45 via a transmission 33. Optionally, another rotary encoder 35 can be connected to the electric motor 34, and another rotary encoder 49 can be connected to the electric motor 48, so that the rotational speeds of the electric motors 34 and 48 can be detected by the rotary encoders 35 and 49. The rotary encoders 35 and 49 can then be implemented essentially like the rotary encoders 25 and 38 and can be components of the control unit 20.

Claims

1. A method for operating conveyor systems, particularly hoists, cranes, continuous conveyors, etc. The conveyor means comprises a drive unit (21) and a control unit (20) that controls the drive unit. The drive unit comprises at least two drive devices (43, 44), and the drive devices are controlled by the control device (22) of the control unit. The rotary encoders (25, 35, 38, 49) of the control unit are connected to the shafts (29, 42) of the drive units of the conveyor means, which are respectively assigned to the drive devices, and in order to detect the rotation of the shafts and control the drive devices, the encoder devices (26, 39) of the corresponding rotary encoders transmit rotation angle signals and / or rotation speed signals to the control device. The control device determines the corresponding rotational speed of the shaft, compares it with a reference rotational speed, and controls the drive device according to the comparison. The control device (22) determines the corresponding acceleration of the shafts (29, 42), compares it with the reference acceleration, and adjusts each drive device (43, 44) according to the reference acceleration. A method characterized in that a load signal is detected by load sensors (36, 37) of a sensor device (23) of the control unit (20) assigned to the drive device (43, 44), and the safety elements (27, 40) of the corresponding rotary encoders (25, 35, 38, 49) determine a load-dependent maximum threshold rotational speed in accordance with the rotation angle signal and / or the rotation speed signal and the load signal, and transmit it to the control device (22) in order to control the drive device.

2. In the method according to claim 1, The control device (22) determines the reference rotation speed according to one of the rotary encoders (25, 42)' rotation angle signal and / or rotation speed signal, and the control device adjusts each drive device according to the reference rotation speed.

3. In the method of claim 2, The control device (22) records the load signals from the load sensors (36, 37) of the sensor device (23) of the control unit (20) assigned to the drive devices (43, 44), compares these with a reference load, and the control device adjusts each drive device according to the reference load.

4. In the method according to claim 3, The control device (22) stores range parameters for rotational speed, acceleration, and / or load, and the reference rotational speed, reference acceleration, and / or reference load are each limited by the range parameters.

5. In the method according to claim 3 or 4, The load signal from the load sensor is recorded by the rotary encoders (25, 35, 38, 49), and each rotary encoder determines a load-dependent variable according to the rotation angle signal and / or the rotation speed signal, and transmits it to the control device (22) in order to control the drive device (43, 44).

6. In the method according to any one of claims 3 to 5, The control device (22) is characterized by limiting the rotational speed of the drive devices (43, 44) or turning off the drive devices when the load is exceeded.

7. In the method according to any one of claims 3 to 6, The method is characterized in that the load signal is recorded for rope load and / or winding load by a plurality of load sensors (36, 37) assigned to each drive device (43, 44).

8. In the method according to any one of claims 1 to 7, The safety element (27, 40) is characterized by determining a function of the load-dependent maximum threshold rotational speed from the rotation angle signal and / or the rotational speed signal and the load signal.

9. In the method according to any one of claims 1 to 8, The safety elements (27, 40) are characterized by correcting the load signals of the load sensors (36, 37) while taking into account the acceleration of the applied load on the conveyor means.

10. In the method according to any one of claims 1 to 9, The method is characterized in that the safety elements (27, 40) determine the operation type of the drive device (43, 44) to be lifting, lowering, overloading, slack rope, or free running, in response to the rotation angle signal and / or the rotation speed signal and / or the load signal, and transmit this to the control device (22).

11. In the method according to any one of claims 1 to 10, The method is characterized in that the switch signals of the terminal switches of the sensor devices of the control unit (20) are recorded by the rotary encoders (25, 35, 38, 49), the rotary encoders determine the relative position of the applied load on the conveyor means in accordance with the switch signals, and the safety elements (27, 40) take the switch signals into account when determining the load-dependent maximum threshold rotational speed.

12. In the method according to any one of claims 1 to 11, The method is characterized in that the load signal is recorded by the counters (28, 41) of the rotary encoders (25, 35, 48, 49), and these counters store the rotation angle signal and / or the rotation speed signal and the load signal during the operating time, determine a load-dependent damage value, and transmit it to the control device (22) to control the drive unit (43, 44).

13. In the method according to any one of claims 1 to 12, The rotary encoders (25, 35, 38, 49) are equipped with an evaluation device. The evaluation device is characterized by recording the load signal, determining the weight of the load applied to the conveyor means from the load signal, and transmitting it to the control device (22).

14. A control unit (20) for conveyor means, particularly hoists, cranes, continuous conveyors, etc. The conveyor means comprises a control device (22) and at least two rotary encoders (25, 35, 38, 49), the rotary encoders being connectable to the shafts (29, 42) of the conveyor means, which are assigned to the respective drive units (43, 44) of the drive unit (21) to detect the rotation of the corresponding shafts. The rotary encoder includes encoder devices (26, 39) that output a rotation angle signal and / or a rotation speed signal to the control device (22) in order to control the drive unit. The corresponding rotational speed of the shaft can be determined by the control device and compared with a reference rotational speed, and the drive device can be controlled by the control device in accordance with the comparison. The control device (22) determines the corresponding acceleration of the shafts (29, 42), compares it with the reference acceleration, and adjusts each drive device (43, 44) according to the reference acceleration. A control unit characterized in that a load signal is detected by load sensors (36, 37) of a sensor device (23) of the control unit (20) assigned to the drive device (43, 44), and the safety elements (27, 40) of the corresponding rotary encoders (25, 35, 38, 49) determine a load-dependent maximum threshold rotational speed in accordance with the rotation angle signal and / or the rotation speed signal and the load signal, and transmit it to the control device (22) in order to control the drive device.

15. In the control unit according to claim 14, A control unit characterized in that one of the rotary encoders (25, 35, 38, 49) includes the control device (22).

16. In the control unit according to claim 14 or 15, The control unit is characterized in that the rotary encoders (25, 35, 38, 49) are incremental encoders and / or absolute encoders.

17. In the control unit according to any one of claims 14 to 16, The control unit (20) is characterized by comprising four or more rotary encoders (25, 35, 38, 49).

18. Conveyor systems, particularly hoists, cranes, etc., The control unit (20) according to claim 14, A conveyor system comprising a drive unit (21) having at least two electric motors (34, 48), a transmission, and two rope drums (30, 45).

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