METHOD FOR OPERATING A MACHINE

Abstract

The invention relates to a method for operating a machine, in particular a grinding machine, comprising the steps of: detecting a workpiece to be machined and setting various setting values of the machine, performing machining of the workpiece, detecting a first actual value and a second actual value during or after performance of the machining, wherein the first actual value is assigned a higher prioritization than the second actual value, comparing the first actual value with a first set value range and the second actual value with a second set value range, and changing the setting values of the machine such that the actual values meet the assigned target value range according to the prioritization.

Claims

1. A method for operating a machine, the method comprising the steps of: detecting a workpiece to be machined and setting a plurality of setting values of the machine; performing machining of the workpiece; detecting a first actual value and a second actual value during or after performance of the machining, wherein the first actual value is assigned to a first priority, the second actual value is assigned to a second priority, and the first priority is a higher priority than the second priority; comparing the first actual value with a first target value range and the second actual value with a second target value range; and changing the plurality of setting values of the machine so that the first and second actual values meet the assigned first and second target value ranges, respectively, according to the respective first and second priorities.

2. The method according to claim 1, wherein the first target value range is selected from: a thickness of the machined workpiece a surface quality of the machined workpiece, and a flatness of a surface of the workpiece.

3. The method according to claim 2, wherein a camera or a radar sensor is used to detect the workpiece to be machined or the machined workpiece.

4. The method according to claim 2, wherein the thickness of the machined workpiece is detected by a tactile sensor or a laser sensor.

5. The method according to claim 1, wherein the second target value range is selected from: energy consumption of the machine, wear of a grinding belt, a suction rate, or a feed rate.

6. The method according to claim 1, wherein the plurality of setting values are selected from: a feed rate of the workpiece, a passage height, a cutting speed of a grinding belt, a contact pressure, a contact force, a number, a selection or a combination of machining aggregates in use, a feed value of an aggregate, a type of a machining unit, and wherein the plurality of setting values are changed by comparing the first actual value with the first target value range and the second actual value with the second target value range, based on the feed rate of the workpiece, the passage height, a workpiece width, the cutting speed of the grinding belt, the contact pressure, the contact force, an ambient temperature or air humidity.

7. The method according to claim 1, wherein the comparing is performed by a control device using artificial intelligence.

8. The method according to claim 1, wherein the machine is configured as a grinding machine, wherein the grinding machine comprises a grinding device, and wherein the grinding device comprises a belt grinding device, a disc brush, a grinding roller, a brush roller, a transverse belt grinding unit, a grinding unit or a combination thereof.

9. The method according to claim 8, wherein the grinding machine comprises a plurality of grinding devices, wherein each of the plurality of grinding devices comprises the grinding device, and wherein components of the respective grinding device of the plurality of grinding devices is controlled by respectively setting at least one setting value of the respective grinding unit.

10. The method according to claim 1, wherein the changed plurality of setting values are stored in a storage device, and wherein the first and second actual values as well as the corresponding first and second target value ranges are stored in the storage device.

11. A machine, comprising: one or more grinding devices configured to perform machining of a workpiece; a first detection device configured to detect a first actual value of the workpiece after or during performance of machining of the workpiece; a second detection device configured to detect a second actual value of the workpiece after or during performance of the machining; and a control device configured to: compare the first actual value with a first target value range and the second actual value with a second target value range, and change a plurality of setting values of the machine to enable the first and second actual values to meet the assigned first and second target value ranges, respectively, according to the respective first and second priorities, wherein the first actual value is assigned to a first priority, the second actual value is assigned to a second priority, and the first priority is a higher priority than the second priority.

12. The machine according to claim 11, wherein: the first detection device is configured to measure a first thickness of the workpiece before the workpiece passes through the one or more grinding devices; the second detection device is configured to measure a second thickness of the workpiece after the workpiece passes through the one or more grinding devices; the first actual value is the first thickness of the workpiece; and the second actual value is the second thickness of the workpiece.

13. The method according to claim 2, wherein a camera or a radar sensor is used to detect the workpiece to be machined and the machined workpiece.

14. The method according to claim 3, wherein the thickness of the machined workpiece is detected by a tactile sensor or a laser sensor.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0030] FIG. 1 shows a schematic structure of a wide belt grinding machine configured to carry out the method according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Preferred embodiments of the method according to the invention will be described by means of the enclosed FIGURE. Although the embodiments described below are to be understood purely as examples, and are not restrictive, features of the embodiments can also be individually used to specify the invention. Moreover, embodiments can be combined with one another in order to form new embodiments of the invention.

[0032] The embodiment example is directed at a grinding process to vividly describe the invention. However, the invention is not limited thereto.

[0033] A grinding machine according to the embodiment comprises a housing 10 accommodating a first grinding device 20 and a second grinding device 30. The grinding machine further comprises a feed mechanism 40 that moves a workpiece W through the housing 10 of the grinding machine.

[0034] The workpieces machined with the grinding machine are preferably formed plate-shaped. In particular, these are workpieces made of wood or wood-based materials that are used, for example, in the furniture or components industry. As a specific example, these can, for example, be furniture fronts; shelves; ceiling, floor or wall panels, or the like.

[0035] A first thickness measurement sensor 50 is provided in the inlet area of the housing 10. The thickness measurement sensor 50 is configured to determine a workpiece thickness before the workpiece W is machined by the grinding machine. The thickness measurement sensor 50 can be a tactile sensor or a non-contact sensor with which the thickness of the workpiece W to be machined is detected.

[0036] A second thickness measurement sensor 60, which can be configured in a similar manner as the first thickness measurement sensor 50, is disposed in the outlet area of the housing 10. The second thickness measurement sensor 60 is configured to determine a workpiece thickness after the workpiece W has passed through the grinding machine.

[0037] In addition, the grinding machine is equipped with further sensors with which the parameters mentioned below can, individually or in combination, be determined.

[0038] The quality of the grinding belt during processing can be determined by means of a grinding belt sensor. The condition of the granulation, and thus the degree of wear, can thereby be determined. For example, a grinding belt sensor can be a radar sensor with which the grinding belt is continuously monitored and evaluated accordingly. In the case of the radar sensor, conclusions can be drawn from the detected intensity of the radiation reflected at the grinding belt as regards the granulation or roughness of the grinding belt, and according to another application, it can be detected when the grain size is reduced due to wear of the grinding belt.

[0039] As an alternative to a grinding belt sensor, the quality of the grinding belt can also be calculated on the basis of the determined engagement time of the grinding belt and the determined service life. For this purpose, the duration of each engagement on a workpiece is detected, in particular by detection of the respective workpiece length in the transport direction.

[0040] The passage height between the conveyor mechanism and the grinding belt can be detected by means of a grinding pad position sensor and/or a position sensor for detecting the position of a grinding roller.

[0041] Furthermore, the feed rate of the conveyor mechanism 40 is detected using a sensor. Alternatively or additionally, the feed rate can be determined based on the control commands used to drive the conveying mechanism 40.

[0042] By means of a tactile or optical width measurement sensor in the inlet area of the housing, the component dimension is determined in a direction perpendicular to the throughfeed direction. Specifically, it is determined whether the workpiece being fed to the grinding devices 20, 30 is wide or narrow.

[0043] The orthogonal force by which the grinding belt is pressed against the workpiece is determined by means of a contact pressure sensor.

[0044] One or more temperature sensors detect the ambient temperature as well as the temperature of the workpiece which heats up during machining.

[0045] Furthermore, the air humidity in the machining area can be determined by means of an air humidity sensor.

[0046] The machine can be provided with a sensor with which the suction rate is determined. This is done, for example, by detecting the number of revolutions of a fan.

[0047] The machine can further be provided with a sensor which determines the energy consumption of the machine.

[0048] As a further sensor, a first optical sensor can be provided in the inlet area and a second optical sensor in the outlet area of the housing 10, and therefore the surface structure, and thus the surface quality, can be determined before and after the grinding process by means of the optical sensors.

[0049] The grinding machine according to the embodiment comprises a control device configured to control the operation of the grinding machine. The aforementioned sensors are connected to the control device and accordingly transmit information continuously or at specific intervals, in particular regarding the quality of the grinding belt, the passage height, the feed rate, the component dimensions, the cutting speed of the grinding belt or belts, the difference between the initial thickness of the workpiece and the actual thickness after grinding, the contact pressure, the temperature or temperatures and the humidity.

[0050] In addition, the control device manages and/or monitors the number and combination of the grinding devices. In the embodiment example, the grinding device 20 is a so-called contact roller unit. The roller of the contact roller unit, which is lower in the vertical direction, presses the grinding belt against a workpiece W moved by the conveyor mechanism 40.

[0051] In the grinding device 30, three rollers are provided for moving the grinding belt, the rollers facing the workpiece being a calibration roller and a deflection roller. A grinding pad is provided between the calibration roller and the deflection roller, which presses the grinding belt against the workpiece to be ground.

[0052] The information acquired by various sensors is combined in the control device of the grinding machine and evaluated for controlling the operation of the grinding machine. Thus, different information can be correlated and coordinated with each other.

[0053] The control device includes a module that performs calculations using an algorithm based on artificial intelligence. This means that the values detected by the sensors and the instructions derived therefrom are continuously detected and revised, with a workpiece thickness and a surface structure (and thus the surface quality) of the workpiece W being used as target value ranges.

[0054] The aforementioned artificial intelligence can be implemented using a neural network. After a learning phase, the neural network can make decisions to determine which setting values have to be changed to achieve the target value ranges. The neural network is able to change various setting values influencing the overall result in such a way that the target value ranges are achieved.

[0055] The target value ranges are prioritized relative to each other. A first target value range can thus be assigned a higher prioritization than a second target value range. Hence, the machine is operated in such a way that the first actual value is in the first target value range. If this is ensured, setting values are further changed, if necessary, such that the second actual value is in the second target value range.

[0056] As a specific example, a certain thickness of a workpiece or a certain surface quality can be selected as a first target value range. In this context, it is also possible to define different first target value ranges, for example a workpiece thickness, a surface quality and a flatness of the surface.

[0057] A high feed rate can be selected as a second target value range.

[0058] According to the prioritization, the result of this is that as long as the first target value range is met, the system works to meet the second target value range to the best possible extent. If the first target value range is no longer met, the setting values are changed such that the first target value range is still met.

[0059] The control device thereby decides which parameters influencing the grinding result should be changed in order to achieve the highest possible quality (low tolerance of the workpiece thickness as well as a specific target value of a surface structure) with simultaneously high productivity or low energy consumption (as examples of a second target value range).

[0060] During operation of a grinding machine, pressure segments in the pressure beam of the grinding machine are activated after a workpiece is detected. It is detected whether a pressure segment, with which a grinding belt is pressed against the workpiece surface, presses onto the workpiece over the entire surface or only part thereof. Accordingly, a higher or lower force is applied to the pressure segments to achieve a specific contact pressure.

[0061] In this context, it can be provided that a detection of the contact pressure is performed. In combination with a detection of the surface of the ground workpiece, the machining results can be optimized. In this context, it can be determined that a certain surface is achieved as a target value range in a certain pressure range.

[0062] For workpieces of similar dimensions, an increase in the contact pressure can possibly lead to higher wear of the grinding belts of the grinding devices 20, 30 which in turn causes shorter maintenance intervals for replacing the grinding belt. The control device can therefore decide to combine a certain contact pressure with a favorable feed rate such that a high machining quality is ensured with low wear of the grinding belts.