Device for Monitoring an Apparatus for Induction Heating of a Metal Material, Method for Automatic Loading and Control System

Abstract

An apparatus for monitoring an apparatus for the inductive heating of a metal material including a detection device and an evaluation device. In order to automate the loading of the inductive heating apparatus with bulk material or metal material, according to the invention the detection device is an optical sensor for detecting distance and the evaluation device is designed to determine, on the basis of the distance detected by the detection device, the fill level of the inductive heating apparatus and to output a corresponding signal, the signal being suitable for further use in a control process for the feeding of metal material to the inductive heating apparatus. The invention also relates to a method for automatically loading an apparatus for the inductive heating of a metal material and to a control system for an apparatus for the inductive heating of a metal material.

Claims

1-15. (canceled)

16. A device for monitoring a device for inductive heating of a metal material, with a detection device and with an evaluation device, wherein the detection device is an optical sensor for detecting a distance, wherein the detection device is a LIDAR sensor, the detection device being configured to emit beams in the ultraviolet, infrared or visible range of light and to determine a distance value for the distance to be measured at a specific measurement time on the basis of the transit time of the measurement pulse between emission and reception after reflection, and in that the evaluation device is configured to determine a fill level (64) of the device for inductive heating on the basis of a distance detected by the detection device and to output a corresponding signal, wherein several distance values corresponding to several distances detected at the same time are taken into account in order to detect bridging in the metal material received by the device for inductive heating, and wherein the signal being suitable for further use in a control process for the supply of metal material to the device for inductive heating . . . .

17. The device according to claim 16, wherein the detection device is configured for time-resolved detection of a distance and output of corresponding distance values, and in that the evaluation device is configured to trace a temporal development of the fill level on the basis of the distance values output by the detection device and to adapt the signal accordingly.

18. The device according to claim 16, wherein the fill level for a specific point in time corresponds to a distance between a reference position fixed relative to the device for inductive heating and a position on the free surface of the metal material received by the device for inductive heating at the specific point in time.

19. The device according to claim 16, wherein the evaluation device is configured for accessing at least one preset and/or detected value for an operating parameter of the device for inductive heating, and in that the evaluation device is configured for recognising bridging in the metal material received by the device for inductive heating, taking into account a temporal development of the fill level and of the at least one preset and/or detected value for an operating parameter of the device for inductive heating.

20. The device according to claim 19, wherein the signal output by the evaluation device is suitable for further use by a warning device, and in that the warning device is configured for outputting a warning signal if the signal contains information about a positive detection of bridging.

21. The device according to claim 16, wherein the detection device is arranged at a conveying device, in particular at a splash guard of a conveying device for supplying metal material to the device for inductive heating.

22. A method for automatically loading a device for induction heating of a metal material, wherein beams in the ultraviolet, infrared or visible range of light are emitted by a detection device configured as a LIDAR sensor and a distance is detected in a time-resolved manner, wherein a distance value for the distance to be measured is determined at a specific measurement time point on the basis of the transit time of the measurement pulse between emitting and receiving after reflection, in that corresponding distance values are output, in that a signal containing information about a fill level of the device for inductive heating is output on the basis of the distance values, wherein several distance values corresponding to several distances detected at the same time are taken into account in order to detect bridging in the metal material received by the device for inductive heating, and in that the supply of metal material to the device for inductive heating is controlled or regulated as a function of the information about a fill level.

23. The method according to claim 22, wherein at least partial loading of the device for inductive heating by a transport device, in particular by a charging trolley or by a movable transport chute, is at least temporarily prevented or continued as a function of the information about a fill level of the device for inductive heating.

24. The method according to claim 23, wherein the at least partial loading is started or resumed when the fill level falls below a predetermined lower limit value, and/or that the at least partial loading is paused or stopped when the fill level exceeds a predetermined upper limit value.

25. The method according to claim 22, wherein it is determined on the basis of the distance values whether the fill level essentially decreases, remains constant or increases over a predetermined period of time, and in that bridging is recognized in the metal material received by the device for inductive heating on the basis of the temporal development of the fill level.

26. The method according to claim 22, wherein preset and/or detected values for at least one operating parameter of the device for inductive heating are retrieved as a function of the temporal development of the fill level and taken into account for the detection of bridging.

27. The method according to claim 22, wherein if the signal contains information about a positive detection of bridging, the supply of metal material to the device for inductive heating is at least temporarily reduced or stopped and/or a warning signal is emitted.

28. A control system for an apparatus for induction heating of a metal material comprising an apparatus according to claim 16 and a control unit, wherein the control unit is configured to regulate or control the supply of metal material to the device for induction heating as a function of a fill level of the device for induction heating.

29. The control system according to claim 28, wherein the control unit is configured to cause at least partial loading of the device for inductive heating by a conveying device, in particular by a charging trolley or by a movable conveying chute, when the fill level falls below a predetermined lower limit value, and/or to pause or stop when the fill level exceeds a predetermined upper limit value.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0097] Further advantages of the features of the invention are apparent from the description of the following embodiments, with reference being made to the accompanying drawing. The drawings,

[0098] FIG. 1 shows an example of a device for induction heating of a metal material;

[0099] FIG. 2 shows detailed view of the device shown in FIG. 1, showing bridging in the metal material being received;

[0100] FIG. 3 shows an embodiment of a device for monitoring a device for inductive heating of a metal material;

[0101] FIG. 4 shows a detailed view of the device from FIG. 3; and

[0102] FIG. 5 shows an embodiment of a control system for a device for inductive heating of a metal material.

DESCRIPTION OF THE INVENTION

[0103] FIG. 1 shows an example of an apparatus 2 for induction heating of a metal material 4 from the prior art with a receiving chamber 6 for receiving a bulk material to be melted in the form of scrap pieces of metal material 4 and with a conveying device 8 for filling the receiving chamber 6. The conveying device 8 is designed as a charging trolley. Depending on the position of a suction bonnet 10, the receiving chamber 6 is available for filling or refilling by means of a pouring section 12 designed as a tapping spout.

[0104] A coil 14 is wound around the receiving chamber 6, which is connected on the one hand to a cooling system 16 and on the other hand to a medium-frequency converter (MF converter) 18. The MF converter 18 is in turn tempered by a further cooling system 20.

[0105] A weighing cell 22 is used to monitor the weight of the receiving chamber 6.

[0106] FIG. 2 shows a detailed view of the device 2 from FIG. 1, wherein bridging has taken place in the received metal material. The receiving chamber 6 can be seen, in which a metal material is partially melted. A layer 26 of a solidified, non-metallic accompanying phase or slag has formed above the melt 24, for example as a result of a previous melting process. Solid individual pieces 27 or scrap components from a metal material 28 to be melted lie above this layer 26. The layer 26 has hard individual pieces 27 that have not yet melted.

[0107] The centre layer 26 forms an airtight seal between the melt 24 and the metal material 28 that is still to be melted and prevents the latter from melting. A space 29 containing gases from the melting process has formed between the layer 26 and the melt 24, which cannot escape due to the airtight layer 26.

[0108] FIG. 3 shows an embodiment of a device for monitoring 30 a device for inductive heating 32 of a metal material 34 with a detection device 36 and with an evaluation device 38.

[0109] The detection device 36 is designed as an optical sensor for time-resolved detection of a distance and output of corresponding distance values. The detection device 36 successively emits a plurality of fanned-out light pulses 40, which at least partially reflect onto the surface 42 of the metal material 34 received in the receiving space 44 of the device for inductive heating 32, and detects the reflected light beams. The detection device 36 calculates the distance to the reflecting surface 42 from the detected light beams or from the time delay between the time of emission of the measuring pulse and the time of detection of the corresponding reflected light beam.

[0110] In FIG. 3, the detection device 36 is arranged at the splash guard 46 of a conveyor 48 and connected to the evaluation device 38 via a cable 50.

[0111] The evaluation device 38 is designed to determine a fill level of the device for inductive heating 32 on the basis of distance values output by the detection device 36 and to output a signal with information about the determined fill level.

[0112] The signal is suitable for further use in a control process, whereby the supply of metal material 34 to the device for inductive heating 32, in this case by means of the conveyor 48, is adjusted taking into account the fill level.

[0113] FIG. 4 shows a detailed view of the device 32 of FIG. 3, with the detected distances shown schematically. The detection device 36 is arranged above the receiving space 44 of the device for inductive heating 32 and can thus detect distances that correspond to the total height of the receiving space 44.

[0114] By emitting a measurement pulse 54 and detecting a corresponding reflected light beam, the distance between the position 56 at which the measurement pulse was emitted and the position 58 at which it was reflected on the free surface of the metal material 34 received by the receiving space 44 can be determined. In the present case, (i) the distance 60 between the position 56 at which measuring pulses are emitted and the position of the edge of the upper opening of the receiving chamber of the device for inductive heating 32 and (ii) the height 62 of the interior of the receiving chamber 44 were stored in advance, so that the fill level 64 or the filling height in the receiving chamber 44 can be determined on the basis of the recorded values and by simple subtraction.

[0115] FIG. 5 shows an embodiment of a control system 66 for a device 68 for inductive heating of a metal material 70, with a device for monitoring 72 a device 68 for inductive heating of a metal material 70 and with a control unit 74.

[0116] The device for monitoring 72 has a detection device 76 and an evaluation device 78. The evaluation device 78 is connected to the control unit 74 for data exchange.

[0117] The control unit 74 is connected to a conveying device 80 of the device for inductive heating 68 to adaptively control the supply of metal material 70 to the receiving space 82 of the device for inductive heating 68 in dependence on information or signals received from the evaluation device 78. In addition, the control unit 74 is also connected to a coil 84 of the device for inductive heating 68 to control the energy supplied to the received metal material 70.

[0118] Furthermore, a control device 88 is provided, which is connected to the evaluation device 78. This control device 88 corresponds to the control device that is provided as standard in devices for induction heating. The configuration shown in FIG. 5 could also be used to retrofit an existing device for inductive heating 68 by adding a control system 66.

[0119] The control device 88 is configured to set all operating parameters of the device for inductive heating 68 and also to detect actual values for these operating parameters. Through the respective connections of the evaluation device 78, the control unit 74 and the control device 88, it is possible to determine the presence of bridging in the metal material 70 on the basis of both distance values output by the detection device 76 to the fill level of the receiving chamber 82 and values for operating parameters.