DRIVE DEVICE FOR A VIBRATORY CONVEYOR, USE OF THE DRIVE DEVICE IN A VIBRATORY CONVEYOR, AND METHOD FOR CHECKING THE FUNCTIONALITY OF A CORRESPONDING VIBRATORY CONVEYOR

Description

[0001] The invention relates to a method for checking the functionality of a vibratory conveyor device and to a drive device for a vibratory conveyor device

[0002] Document CN 107 352 227 A discloses a drive device for a vibratory conveyor device, the drive device comprising: a) a frame with a base plate arranged at a lower end of the frame and a plurality of supports arranged peripherally on the base plate in a partial circle and extending in the direction of a longitudinal axis; b) an anchor plate which is arranged at an upper end of the frame and is connected to a support in a horizontally and vertically oscillatable manner by means of a first spring assembly; c) an acceleration sensor coupled to the anchor plate;d) a magnetic drive which is arranged below the armature plate and at a distance therefrom and which comprises a counterweight so that the armature plate can be made to oscillate by means of magnetic force transmission, wherein e) the first spring assemblies enclose an angle a > 90° with the armature plate in the rest state of the drive device so that the driving force exerted on the armature plate by the magnetic drive can be divided into horizontal and vertical components;

[0003] A vibratory conveyor device for dedusting and deburring tablets is known from document EP 1 322 533 B1 KRÄMER. This known vibratory conveyor device essentially comprises a helical conveyor trough, a drive device for causing the conveyor trough to vibrate, and a suction device for extracting dust from the area of ​​the conveyor trough.

[0004] However, with this known vibratory conveyor, faults in the conveyor trough or difficult start-up behavior of the vibratory conveyor caused by long downtimes cannot be immediately detected and taken into account when starting the device. Furthermore, fault conditions can occur during operation of the vibratory conveyor, which can damage the drive mechanism and conveyor trough.

[0005] The invention aims to remedy this situation. The invention is based on the object of creating a method for performing a status analysis of the vibratory conveyor device in order to subsequently make a statement about its functionality. The invention achieves this object with a method for testing the functionality of a vibratory conveyor device, which has the features of claim 1, and with a drive device for a vibratory conveyor device, which has the features of claim 8.

[0006] The advantages achieved by the invention are essentially that thanks to the inventive method: A) before operation: by comparing the impulse response with a reference impulse response, defects in the conveyor trough, such as incorrect assembly of the conveyor trough or a lack of control of the spring rate when starting the vibratory conveyor device, can be detected, so that in such cases the drive device can be prevented from being switched on; and faults in the start-up behavior of the drive devices, which can occur due to long downtimes, can be detected. With such vibratory conveyor devices, long downtimes can occur, which can cause the drive device to exhibit differentiated start-up behavior. In known vibratory conveyor devices, however, this behavior is not taken into account by the control system, which can lead to increased mechanical stress on the device and thus to its failure.By evaluating the impulse response, this fact can be identified at an early stage and taken into account when switching on the vibratory conveyor. B) During operation, the recorded values ​​for the parameters voltage amplitude, frequency, acceleration and temperature can be used for, e.g.: a comparison of the recorded values ​​for the parameters with tolerance bands, so that a decision can be made as to whether operation of the vibratory conveyor should continue or be suspended with an error message; and / or after operation, the recorded values ​​for the parameters can be compared with stored long-term data, so that a trend towards a change can be identified and a decision can be made as to whether a warning should be issued or whether later commissioning can take place as standard.

[0007] A number of technical terms important for the invention are defined in more detail below: Impulsantwort (111)

[0008] In the following, the impulse response is referred to as the output signal of an oscillating device in which a needle pulse (Dirac pulse) is applied as the input signal.

[0009] According to the invention, the output variable, i.e., the impulse response, is generated from a pulse (input signal). The excitation is pulse-like, i.e., extremely short compared to the oscillation period of the device. The unit impulse function (input signal) consists of an approximate needle pulse (Dirac pulse). Although such a needle pulse cannot be physically realized exactly, the response behavior (output variable) for excitations with a short pulse and high amplitude can provide information regarding dynamic properties such as natural frequency and damping.

[0010] If all conveyor screws are correctly installed, there is no change in the spring rate, and there is no long-term damage to the drive device, then the vibratory conveyor device is in normal operation. By applying the aforementioned pulse (input signal), the decay behavior (output variable) can be recorded and analyzed. This behavior is now considered the reference behavior - this applies both in the time and frequency domains. If no conveyor trough (conveyor screw) is installed on the drive device, the vibration behavior after the applied and predefined pulse will be different than when the conveyor trough (conveyor screw) is installed. Therefore, as soon as the pulse response (output variable) of the vibratory conveyor device deviates from the reference behavior, a fault condition must be assumed.

[0011] Based on the clear characterization of the error states (which also includes data from other sources), the corresponding error can be derived and reported. Toleranzband (121)

[0012] The excitation coil is controlled by a closed-loop system that can respond to changing vibration amplitudes (due to increased mass on the coil) via feedback from the acceleration sensor by adjusting the voltage amplitude at the coil using the frequency converter. External system errors such as a broken weld on the coil or exceeding the maximum fill level in the coil can lead to incorrect amplitude control and thus to defects in the drive device. By comparing the current voltage amplitude with a predefined tolerance band, such malfunctions can be detected early on. The same applies to the output frequency of the frequency converter. In addition to the voltage amplitude and frequency, the current acceleration is also compared with a predefined tolerance band in order to detect a possible malfunction of the acceleration sensor at an early stage. Parametervergleich (131)

[0013] In the following, parameter comparison refers to the further processing and combination of recorded state variables from different data sources with the aim of detecting a tendency for the recorded parameter to approach its tolerance band limit.

[0014] For example, the temperature profile of the coil is analyzed over its service life so that a statement can be made regarding the necessary service intervals and the functionality of the vibratory conveyor device is guaranteed in the long term. OPC UA (141)

[0015] OPC UA (Open Platform Communications United Architecture) is the standard introduced by the OPC Foundation for platform-independent and service-oriented (SOA) data exchange.

[0016] This newly evaluated data can protect the vibratory conveyor (dust collector) from damage, consequential damage, and improper operation. Furthermore, process reliability can be significantly improved through predictive maintenance.

[0017] According to the invention, the following step is performed after step A5): A6) Activation of the start procedure for operation with or without reduced starting drive power of the vibratory conveyor device. When activating the start procedure for operation with reduced starting drive power, a difficult start-up behavior of the device caused by a long downtime can be taken into account. A device defect due to increased mechanical stress during start-up of the drive device can thus be prevented.

[0018] In another embodiment, the start-up procedure reduces the drive power of the drive device and increases it to 100% after a period of time Δt > 0. This provides the advantage that, based on the evaluation of the impulse response, a difficult start-up behavior of the device caused by a long downtime can be taken into account when switching on the vibratory conveyor by automatically reducing the drive power, for example, to 50%. After this so-called "soft start," the power can be increased to 100% after a predefined time. This measure prevents the vibratory conveyor from being damaged due to the long downtime.

[0019] In another embodiment, the drive power of the drive device is reduced to at most 80%, preferably to at most 50%.

[0020] In a further embodiment, the method comprises the following step before step A1): AO) generating a reference impulse response by applying a short-term drive pulse to a drive device of the vibratory conveyor device, wherein the drive device is not exposed to increased mechanical stresses.

[0021] In a further embodiment, the impulse response caused by the vibratory conveyor device in step A2) can be detected as a function of time or as a function of the frequency of the impulse response by means of an acceleration sensor arranged on the vibratory conveyor device.

[0022] According to the invention, after step B2) during operation of the vibratory conveyor device, the following steps are carried out: B3) comparing the recorded parameters with predefined tolerance bands using the computer; and B4) determining by means of the computer whether: (i) the operation of the vibratory conveyor device should be continued without restrictions, or (ii) the operation of the vibratory conveyor device should be suspended with an error message. The advantages of these tolerance bands are, in particular, that Defects in the vibratory conveyor system, such as weld seam breakage, excessive fill levels, or acceleration sensor errors, can be detected. If the detected parameters (voltage amplitude, frequency, and acceleration of the excitation system) are outside the respective predefined tolerance ranges, a potential error condition must be assumed that could damage the drive system. By monitoring the parameters, a shutdown can be initiated to protect the drive system from damage; and Overheating of the coil is prevented by continuously monitoring the temperature at the excitation coil.

[0023] In another embodiment, the following steps are carried out after operation of the vibratory conveyor device: C1) comparing the parameters caused by the vibratory conveyor device, such as voltage amplitude, frequency, acceleration, and temperature, recorded in steps B3) and B4) during operation of the vibratory conveyor device and forwarded to the computer, with stored long-term data using the computer; and C2) determining using the computer whether: a) a trend towards a change in the parameters is detectable and a warning should be issued; or b) operation can continue as normal. The advantages achievable through this parameter comparison are that: the current operating parameters are compared with the reference parameters in order to define the actual state for further operation. Here, the values ​​are compared with the reference parameters determined in the test with regard to temperature profile, acceleration, voltage amplitude and frequency; based on a parameter comparison, process reliability can be increased by detecting a change in a parameter towards its tolerance band limit over a longer period of time, even if the value is currently still within the permissible tolerance range. In contrast to the process during operation, such a change can thus be detected at an early stage and measures can be initiated; and great potential for further development projects and customer-specific applications can be analyzed by compiling the determined data and findings from all dust extractors built.

[0024] In a further embodiment, the method comprises the following steps: D1) Providing the determined computer parameters and data to a higher-level operating system via OPC UA; and D2) Capturing the data input from the higher-level operating system. The advantages of transmitting data via OPC UA are primarily that the determined process parameters and data can be transferred to higher-level operating systems using OPC UA, thus ensuring that synchronous time stamps are available across the interface boundary; and error messages, associated troubleshooting documents, operating instructions and work instructions, as well as any information for process optimization, can be displayed on the higher-level system.

[0025] In a particular embodiment of the drive device, the angle α at least 120°, preferably at least 105°.

[0026] In another embodiment of the drive device, the counterweight can be assembled from a selectable number of individual weights. This offers the advantage that by adding or removing individual weights, the complete drive device can be assembled in such a way that specific counterweights can be installed for different conveying heights from 800 to 2,000 mm.

[0027] In a further embodiment, the drive device additionally comprises a frequency converter for applying a drive pulse, a signal evaluation unit for detecting the impulse response caused by a conveyor trough and a computer.

[0028] A preferred use of the drive device according to the invention is its arrangement in a vibratory conveyor device for dedusting and / or deburring tablets and capsules.

[0029] The invention and further developments of the invention are explained in more detail below with reference to the partially schematic representations of an embodiment.

[0030] They show: Fig. 1a a schematic representation of an embodiment of the method according to the invention for checking the functionality of a vibratory conveyor device by means of a condition analysis before operation; Fig. 1b a schematic representation of an embodiment of the method according to the invention for checking the functionality of a vibratory conveyor device by means of a condition analysis during operation and after operation; Fig. 2 a side view of a vibratory conveyor device together with an embodiment of the drive device according to the invention; Fig. 3 a perspective view of the Fig. 2 illustrated embodiment of the drive device according to the invention; and Fig. 4 a schematic representation of the Fig. 2 illustrated embodiment of the drive device according to the invention together with the peripheral devices.

[0031] In Fig. 1a is an example of an embodiment of the method according to the invention for checking the functionality of a vibratory conveyor device 1 ( Fig. 2 ) by means of a condition analysis 100a before operation.

[0032] The method 110 prior to operation is characterized in that, based on a defined drive pulse, the drive device 2 ( Fig. 2 and 3 ) of the vibratory conveyor device 1 and the analysis of the resulting impulse response, a statement is made about the condition of the vibratory conveyor device 1 immediately before operation.

[0033] The pre-operational procedure 110 essentially comprises the following steps: Applying a drive pulse to a drive device 2 of the vibratory conveyor device 1 before operation of the vibratory conveyor device 1 by means of a frequency converter 3 ( Fig. 4 ); detecting the impulse response caused by the vibratory conveyor device 1 as a function of time or as a function of the frequency of the impulse response by means of a signal evaluation unit 5; forwarding the detected impulse response by the signal evaluation unit 5 to the computer 6 ( Fig. 4 ); comparing the recorded impulse response with a reference impulse response 111 by means of the computer 6; and finally, the computer 6 determines whether: a) a start procedure for operation with reduced starting drive power of the vibratory conveyor device 1 should be activated, or b) a start procedure for operation without reduced starting drive power of the vibratory conveyor device 1 should be activated, or c) operation should be suspended.

[0034] The following status data 112 are recorded using the recorded impulse response: Condition of the conveyor trough 8; check the spring rate of the vibratory conveyor 1; and possible material fatigue.

[0035] In Fig. 1b An embodiment of the inventive method 120 for checking the functionality of a vibratory conveyor device 1 by means of a condition analysis 100b during operation is shown. During operation of the vibratory conveyor device 1, the parameters caused by the vibratory conveyor device 1, such as the coil temperature of the drive device 2, acceleration, frequency, and voltage amplitude, are recorded and continuously monitored by the signal evaluation unit 5. Furthermore, the recorded voltage amplitude, frequency, acceleration, and temperature are forwarded by the signal evaluation unit 5 to the computer 6.

[0036] According to the invention, the method 120 additionally comprises the following steps during operation of the vibratory conveyor device 1: Comparing the recorded parameters with predefined tolerance bands 121 by means of the computer 6; and determining by means of the computer 6 whether: a) the operation of the vibratory conveyor device 1 should be continued without restrictions, or b) the operation of the vibratory conveyor device 1 should be suspended with an error message.

[0037] Functionality is verified based on predefined tolerance bands 121 of the respective parameters. Furthermore, further condition data 122, e.g., the condition of the weld seam and / or the fill level in the vibratory conveyor 1, are determined from the recorded parameters.

[0038] Also by way of example and not by way of limitation, the method 130 for checking the functionality of a vibratory conveyor device 1 ( Fig. 2 ) by means of a condition analysis 100c after operation, which comprises the following steps: Comparing the parameters recorded during operation of the vibratory conveyor device 1 and transmitted to the computer 6, such as voltage amplitude, frequency, acceleration and temperature, with stored long-term data 131 by means of the computer 6; and determining by means of the computer 6 whether: a) a tendency towards a change in the parameters is recognizable and a warning should be issued; or b) operation can continue as standard.

[0039] The condition analysis immediately after operation includes a parameter comparison and primarily serves to compare the recorded current drive parameters with the respective starting values ​​and to provide a statement about the completed operation. In addition, a statement about the current condition is also made, and additional condition data 132 is provided for assessing process reliability, service intervals, potential development potential, and customer-specific projects.

[0040] Using the communication interface 140, the data is forwarded via OPC UA 141 (Open Platform Communications United Architecture) to a higher-level operating system 4, which can inform the user about the current status of the vibratory conveyor 1 or possible future error conditions. Time stamps, process parameters, error messages, and documentation are transmitted as additional status data 142.

[0041] In Fig. 2 1 shows a vibratory conveyor device 1 with an embodiment of the drive device 2 according to the invention, wherein the vibratory conveyor device 1 comprises a helical conveyor trough 8 coaxial with a central axis 9 and, below the conveyor trough 8, a drive device 2 with a longitudinal axis 10 collinear with the central axis 9. For deburring and dust removal, tablets or capsules are fed to the inlet of the conveyor trough 8 and, due to the vibrations, travel upwards along the conveyor trough 8, where they finally leave the vibratory conveyor device 1 again through the outlet. In this way, the tablets or capsules are thoroughly vibrated and rub against each other and against the walls of the conveyor trough 8, losing any burrs due to this mechanical stress.

[0042] In Fig. 3 an embodiment of the drive device 2 according to the invention is shown, which essentially comprises a frame 16 with a longitudinal axis 10 extending in the vertical direction during operation of the drive device 2, a base plate 18 and a plurality of supports 17 arranged peripherally on the base plate 18 in a partial circle and extending in the direction of the longitudinal axis 10, an armature plate 14 which is arranged at an upper end of the frame 16 and is connected horizontally and vertically to a support 17 by means of a first spring assembly 15a, a magnetic drive 13 which is arranged below the armature plate 14 and at a distance from it, a counterweight 11 and is connected to a support 17 by means of a second spring assembly 15b, so that the armature plate 14 can be made to oscillate by means of magnetic force transmission.The magnetic force is transmitted from the magnetic drive 13 to the armature plate 14 via a number of permanent magnets arranged in or on the armature plate 14 (not shown). When the drive device 2 is at rest, the first and second spring assemblies 15a, 15b form, by way of example and not by way of limitation, an angle α of approximately 105° with the armature plate 14, so that the drive force exerted on the armature plate 14 by the magnetic drive 13 is divided into horizontal and vertical components. The conveyor trough 8 is made to oscillate by means of the magnetic drive 13 through the force transmission to the armature plate 14. The spring assemblies 15, from which the conveyor trough 8 and counterweight 11 are suspended, are mounted at a fixed angle to the drive plane of the magnetic coil. The ratio of the angle between the spring assembly 15 and the armature plate 14 results in a distribution of the drive forces on the armature plate 14 in the horizontal and vertical directions for small amplitudes.Furthermore, an acceleration sensor 7 is attached to the fastening elements of the anchor plate 14, to which the first spring assemblies 15a are attached.

[0043] The mechanical structure of the drive device 2 is based on a counterweight 11. The vibration forces are thus compensated via the counterweight system. Here, the mass – the conveyor trough 8 – oscillates in exactly the opposite direction to the second mass – the counterweight 11. This compensation minimizes the transmission of vibration forces to the outer housing. The magnetic drive 13 is completely encapsulated in the counterweight 11, along with a temperature sensor (not shown).

[0044] As in Fig. 4In this embodiment, the drive device 2 additionally comprises a frequency converter 3 for applying the drive pulse, a higher-level operating system 4, a signal evaluation unit 5 for detecting the pulse response and a computer 6 which is suitably programmed to carry out the method according to the invention described above.

[0045] The computer 6 includes an OPC UA (Open Platform Communications United Architecture) interface for connecting to a higher-level operating system 4, allowing the vibratory conveyor 1 to be used independently of manufacturers, programming languages, and operating systems. The vibratory conveyor 1 can thus be connected to any OPC UA tablet press, as well as to higher-level control systems, without requiring any modifications. The standardized interfaces enable quick and easy access to data and applications and simplify the transmission of alarms and audit trails. Furthermore, the simple and secure transmission and collection of data from the drive device 2 enables improved predictive maintenance.Using the acquired drive data, such as the frequency range or vibration amplitude, maintenance information can be derived, allowing proactive maintenance and minimized downtime. Ideally, a malfunction or incorrect operation can be predicted before it has any adverse effects or failures.

[0046] The computer 6 evaluates, among other things, the impulse response recorded by the signal evaluation unit 5, so that, for example, the condition of the conveyor trough 8—e.g., whether it is present or only partially assembled—can be detected before operation and whether the spiral tower with the conveyor trough 8 is correctly assembled can be determined. Furthermore, not only can the correct assembly of the spiral tower be verified, but information about the fill level of the conveyor trough 8 can also be obtained.

[0047] The conveyor trough 8 of the vibrating conveyor device 1 can be completely emptied using an emptying mode. For this purpose, a corresponding low-vibration emptying program for different tablets or capsules can be selected, and the conveyor trough 8 of the vibrating conveyor device 1 can be completely emptied in the low-frequency range.

Claims

1. Method for checking the functionality of a vibratory conveyor device (1) with a drive device (2) according to one of claims 8 - 12 by means of a condition analysis which is carried out either before operation or during operation of the vibratory conveyor device (1), wherein A) the method to be carried out before operation comprises the following steps: A1) applying a drive pulse to the drive device (2) of the vibratory conveyor device (1) prior to operation of the vibratory conveyor device (1) by means of a frequency converter (3); A2) detecting the impulse response caused by the vibratory conveyor device (1) as a function of the time or as a function of the frequency of the impulse response by means of a signal evaluation unit (5); A3) forwarding the detected impulse response by the signal evaluation unit (5) to a computer (6); A4) comparing the detected impulse response with a reference impulse response by means of the computer (6); A5) determining by means of the computer (6) whether: a) a starting procedure for an operation with reduced starting drive power of the vibratory conveyor device (1) is to be activated, or b) a start procedure for an operation without reduced start drive power of the vibratory conveyor device (1) is to be activated, or c) operation is to be suspended; and A6) activating the start procedure for an operation with reduced or without reduced start drive power of the vibratory conveyor device (1); B) the method to be performed during operation comprises the following steps: B1) detecting the voltage amplitude, frequency, acceleration and temperature caused by the vibratory conveyor device (1) during operation of the vibratory conveyor device (1) by means of the signal evaluation unit (5); and B2) forwarding the detected voltage amplitude, frequency, acceleration and temperature by the signal evaluation unit (5) to a computer (6); B3) comparing the recorded parameters with predefined tolerance bands in each case by means of the computer (6); and B4) determining by means of the computer (6) whether: (i) the operation of the vibratory conveyor device (1) is continued without restrictions, or (ii) the operation of the vibratory conveyor device (1) is to be suspended with an error message.

2. Method according to claim 1, characterized in that the drive power of the drive device (2) is reduced by the starting procedure and is increased to 100% after a period of time Δt > 0.

3. Method according to claim 1 or 2, characterized in that the drive power of the drive device (2) is reduced to a maximum of 80%, preferably to a maximum of 50%.

4. Method according to one of claims 1 to 3, characterized in that the method comprises the following step before step A1): AO) generating a reference impulse response by applying a short-time drive impulse to a drive device (2) of the vibratory conveyor device (1), wherein the drive device (2) is not subjected to any increased mechanical stresses.

5. Method according to one of claims 1 to 4, characterized in that the impulse response caused by the vibratory conveyor device (1) in step A2) can be detected as a function of time or as a function of the frequency of the impulse response by means of an acceleration sensor (7) arranged on the vibratory conveyor device (1).

6. Method according to claim 1, characterized in that the following steps are carried out after operation of the vibratory conveyor device (1): C1) comparing the parameters such as voltage amplitude, frequency, acceleration and temperature caused by the vibratory conveyor device (1) and recorded under steps B3) and B4) during operation of the vibratory conveyor device (1) and forwarded to the computer (6) with stored long-term data by means of the computer (6); and C2) determining by means of the computer (6) whether: a) a trend change in the parameters is recognizable and a warning should be issued; or b) operation can be continued as standard.

7. Method according to one of claims 1 to 6, characterized by the further steps: D1) providing the determined parameters and data of the computer (6) to a higher-level operating system (4) via OPC UA; and D2) acquiring the data input from the higher-level operating system (4).

8. Drive device (2) for a vibrating conveyor device (1), wherein the drive device (2) comprises a) a frame (16) having a base plate (18) arranged at a lower end of the frame (16) and a plurality of supports (17) arranged peripherally on the base plate (18) in a pitch circle and extending in the direction of a longitudinal axis (10); b) an anchor plate (14), which is arranged at an upper end of the frame (16) and is connected by means of a first spring assembly (15a) to a respective support (17) so as to be horizontally and vertically oscillatable; c) an acceleration sensor (7) coupled to the anchor plate (14); and d) a magnetic drive (13), which is arranged below the armature plate (14) and at a distance therefrom, comprises a counterweight (11) and is connected to a respective support (17) by means of a second spring assembly (15b), so that the armature plate (14) can be caused to vibrate by magnetic force transmission, wherein e) the first and second spring assemblies (15a, 15b) enclose an angle α > 90° with the armature plate (14) in the rest state of the drive device (2), so that the drive force exerted by the magnetic drive (13) on the armature plate (14) can be divided into horizontal and vertical components.

9. Drive device (2) according to claim 8, characterized in that the angle α is at least 120°, preferably at least 105°.

10. Drive device (2) according to claim 8 or 9, characterized in that the counterweight (11) can be composed of a selectable number of individual weights (12).

11. Drive device (2) according to one of claims 8 to 10, characterized in that the drive device (2) additionally comprises a frequency converter (3) for applying a drive pulse, a signal evaluation unit (5) for detecting the impulse response caused by a conveyor trough (8) and a computer (6).

12. Use of the drive device (2) according to one of claims 8 to 11 in an oscillating conveyor device (1) for dedusting and / or deburring tablets and capsules.