METHOD FOR OPERATING A WORKMACHINERY, AS WELL AS A WORKMACHINERY

Description

[0001] The invention relates to a method for operating a workpiece processing system and to a workpiece processing system according to the preambles of the respective dependent claims.

[0002] DE 10 2020 115 462 A1 describes a workpiece processing device in the form of a panel saw. With this device, large-format, panel-shaped workpieces can be divided into strip-shaped semi-finished products by longitudinal cuts and then further divided into finished workpieces by cross-cuts and, if necessary, additional cuts. These finished workpieces can be used, for example, in furniture manufacturing.

[0003] A typical panel saw includes a workpiece feeder, for example, in the form of a panel storage unit. This unit serves to feed or provide the stored, large-format, panel-shaped workpieces to the panel saw. In this case, the workpiece processing unit is the "destination" of the workpiece feeder. Such a panel storage unit can also be used to retrieve and temporarily store workpieces that have only been partially processed by the panel saw. In this case, the workpiece processing unit is the "source" of the workpiece feeder.

[0004] For moving the large-format, plate-shaped workpieces, such a panel storage system, for example, has a gantry robot with a suction traverse that uses suction cups to grip the top surface of a large-format, plate-shaped workpiece, lift it, and move it to the panel saw. The entire assembly of workpiece feeding device and workpiece processing device can form a workpiece processing system. Such a workpiece processing system can comprise a workpiece feeding device and several workpiece processing devices functionally coupled to it.

[0005] US 2011 / 0204720 A1 describes a power distribution network for supplying electricity to residential buildings, industrial buildings, etc., in which an emergency procedure is executed in the event of a power outage. The article JAECH AARON ET AL: "Real-Time Prediction of the Duration of Distribution System Outages," January 2019, deals with predicting the duration of power outages using historical data. EP 2 379 286 B1 describes a robot that is powered by an energy reservoir during a power outage.

[0006] The present invention aims, on the one hand, to improve the safety in the operation of such a workpiece processing system and, on the other hand, to enable the most productive operation of the workpiece processing system even when the energy supply is not always guaranteed.

[0007] This task is solved by the method and the workpiece machining system with the features of the independent claims. Advantageous further developments are mentioned in the dependent claims.

[0008] An advantage of the present invention is that an uncontrolled shutdown of at least one part of the workpiece processing system in the event of a failure of the first power supply unit ("power failure") is prevented with high reliability.

[0009] Simultaneously, the operation of the workpiece processing system during a power outage is optimized with regard to the expected duration of the outage, thereby increasing the productivity of the workpiece processing system. Safety is also enhanced, as the predefined emergency procedure prevents workpieces from being moved uncontrollably, for example, from falling. It is even possible for certain intended process steps to be carried out by the workpiece processing system during a power outage without operator intervention, further increasing productivity and efficiency. The present invention also enables a reduction in the time required to restart the entire workpiece processing system after a power outage.

[0010] This is based on an intelligent optimization of the emergency procedure based on the expected duration of the power outage. For this purpose, the durations of power outages that have occurred in the past can be stored and analyzed to determine the expected duration of future outages.

[0011] Specifically proposed is a method for operating a workpiece processing system that includes a workpiece processing device in the form of a panel saw for dividing large-format panels, for example made of wood, and a workpiece feeding device, for example a surface storage system, for example with portal robot(s) and suction traverse(s).

[0012] According to the invention, such a workpiece machining system has a first electrical power supply unit and a second electrical power supply unit. The primary electrical power supply unit is the first electrical power supply unit, as it provides the electrical energy necessary for the normal operation of the workpiece machining system to the individual components of the system. The first electrical power supply unit is typically the public power grid. This electrical energy is used, for example, to operate electronic control and regulating devices, such as computers, to operate pneumatic and / or hydraulic valves, to operate sensors and electric motors, to operate display devices, etc.

[0013] The second electrical power supply device is the secondary electrical power supply device, which is only used in the event of a failure of the primary electrical power supply device ("power outage"). For example, the secondary electrical power supply device can include an electrical energy storage device, such as accumulators or rechargeable batteries, and / or an emergency power generator, such as a generator driven by an internal combustion engine.

[0014] The provision of electrical power by the second electrical power supply unit allows a predefined emergency procedure to be implemented in the event of a power outage. For example, such an emergency procedure could include the controlled shutdown of at least the aforementioned control and / or regulating devices (computers), thereby preventing data loss. Relevant process data (e.g., a current process step, etc.) can be saved and secured for subsequent evaluation and further action during the power outage.

[0015] According to the invention, at least one parameter characterizing the specified emergency procedure depends on the expected duration of the power outage. This means that the specified emergency procedure applied when the expected duration of the power outage is relatively short differs from the specified emergency procedure applied when the expected duration of the power outage is relatively long. This can be achieved, for example, by comparing the expected duration of the power outage with one or more limit values, with each corresponding interval defined by the one or more limit values ​​being assigned a corresponding emergency procedure according to which the workpiece processing system, or at least a section of the workpiece processing system, is operated.The limit value can be chosen such that, even if the expected duration is less than the limit value, a specific and optimized number of process steps can still be carried out. It is possible for the limit value(s) and / or the types of corresponding emergency procedures to be predefined, for example, depending on the design or type of the workpiece processing system, and / or defined by the operator of the workpiece processing system. Furthermore, the limit value can also depend on the status of the workpiece processing system, for example, on the charge level of the secondary electrical power supply unit.

[0016] The expected duration of a power outage must be determined beforehand and communicated to a control and / or regulating device of the workpiece processing system. For example, it can be determined by recording the frequency and duration of power outages that occurred during the operation of the workpiece processing system over a previous period and storing this data as "historical" data. In the simplest case, the expected duration can be calculated by taking the arithmetic mean of the durations of past outages.

[0017] According to the invention, the parameter that characterizes the predetermined emergency procedure is at least one from the following group: the position of a process step performed by the workpiece processing system within a series of several process steps, the number of process steps performed by the workpiece processing system, the speed and / or speed profile of the execution of at least one process step performed by the workpiece processing system, and the duration of at least one process step performed by the workpiece processing system. Different positions of process steps can, for example, be used to prioritize certain process steps depending on the expected duration of the failure. Furthermore, a greater number of process steps can be executed if the expected duration is longer than if it is shorter.However, it is also conceivable that if a longer expected duration is anticipated, fewer process steps are carried out in order to save energy and thus ensure certain basic functions over the expected longer duration of the power outage.

[0018] For example, if a longer downtime is expected, the workpiece processing system or a part thereof can be put into an energy-saving state, which may not be necessary if a shorter downtime is expected. Adjusting the speed and / or speed profile of a process step is also particularly effective in reducing energy consumption. By reducing the speed and / or acceleration of driven parts, energy consumption can be lowered and the duration of the emergency process extended.

[0019] During further training, the emergency procedure is designed to include: supplying electrical power from the secondary power supply unit to a safety device of the workpiece processing system. Maintaining the operation of the workpiece processing system's safety device during a power outage is therefore prioritized. For example, the workpiece processing system (or even just a section of it) can include, as a safety device, monitoring a specific area for the presence of personnel. This area could, for instance, include a workpiece feeder. In this case, the safety zone would encompass, for example, both the workpiece processing unit and the workpiece feeder of the workpiece processing system.

[0020] Such a safety device can, for example, include light barriers and / or access doors, and / or cameras and image recognition and evaluation equipment. The use of, for example, a safety laser scanner and / or safety mats would also be conceivable. Further operation of the workpiece processing system would be completely prohibited if such a safety device were to malfunction. Therefore, an active safety device is a prerequisite for operating the workpiece processing system using an emergency procedure. The measure according to the invention thus creates the prerequisite for being able to continue operating the workpiece processing system, or at least a part of it, during the emergency procedure. An emergency shutdown of the entire workpiece processing system is therefore unnecessary.

[0021] In a further development, it is stipulated that the workpiece processing system comprises at least one workpiece processing unit for machining workpieces and a workpiece feeding unit for feeding workpieces to the workpiece processing unit. Furthermore, in the event of an expected initial and comparatively long failure of the primary electrical power supply, the emergency procedure includes: terminating the movement of a workpiece by the workpiece feeding unit—preferably a movement that began before the power failure and was ongoing at the start of the power failure—by means of a controlled placement of the workpiece. This requires that the workpiece feeding unit continues to be fully supplied with electrical energy by the secondary electrical power supply unit during the emergency procedure.

[0022] The workpiece processing device is a panel saw of the type described above. The workpiece feeding device can be a flat storage system, also of the type described above. The measure according to the invention ensures that if the expected duration of the power outage is longer than the possible duration of the provision of electrical energy by the second electrical power supply device, workpieces in the feeder are not released uncontrollably when no electrical energy is available, but rather the workpiece feeding device is brought to a safe state in a controlled manner, in which it can remain until electrical energy is available again.

[0023] To this end, an initial evaluation can be performed to determine which planned process steps can still be carried out with the electrical energy available during the expected duration of the outage. Thus, when a power outage occurs, the current state of the workpiece processing system, including the active jobs of the workpiece processing unit and the workpiece feeding unit, is evaluated, and an "intelligent" response to the power outage is initiated based on this evaluation. If the capacity of the secondary electrical power supply reaches a critical level during an impending power outage, appropriate action is taken. For example, a control and / or regulating unit of the workpiece feeding unit can be shut down in a controlled manner, and the current process data can be saved.

[0024] Further training in this area stipulates that the emergency procedure includes: putting the workpiece feeder into an energy-saving state after the controlled placement of the workpiece. This reduces the time required to restart the workpiece feeder after a power outage. Once the power outage is over, the workpiece feeder can automatically return to its normal state without operator intervention and immediately resume feeding workpieces.

[0025] In a further training, it is stipulated that the workpiece processing system includes at least one workpiece processing unit for machining workpieces and one workpiece feeding unit for feeding workpieces to the workpiece processing unit. Furthermore, in the event of an expected second, comparatively short, failure of the first electrical power supply, the emergency procedure includes: continuation of a workpiece movement initiated before the failure by the workpiece feeding unit, which does not have the workpiece processing unit as its source or destination, as intended before the failure. This takes into account the fact that, typically, the workpiece processing unit, for example, the panel saw, is not supplied with sufficient electrical power from the second electrical supply to allow it to continue operating.Typically, only one control and / or regulating device of the workpiece processing equipment is supplied with electrical energy in such a way that it can be controlled and shut down while storing important current operating data.

[0026] It is therefore possible that if the primary electrical power supply fails, the workpiece processing equipment will not be in a state where it can receive a workpiece. However, if the power outage is expected to be short, other activities already started by the workpiece feeding system can be carried out and completed as planned, and thus continued. The period during the power outage is therefore not entirely unproductive for this training.

[0027] An exception to this is the case where the power failure occurs while the workpiece feeder is in the process of placing a workpiece into the workpiece processing unit. In this case, it can be assumed that the workpiece processing unit is in a state where it can receive the workpiece. Therefore, in this exceptional case, the process step can be completed, i.e., the workpiece can be placed into the workpiece processing unit.

[0028] In a training exercise for this purpose (anticipated short power outages), it is stipulated that at least one movement to be initiated after and during the power outage, and thus during the emergency procedure, is carried out essentially unchanged. This also leads to productive use of the power outage period and thus to an overall increase in the productivity of the workpiece processing system.

[0029] Further training in this area will cover movements from the following groups: storing a workpiece, relocating a workpiece, clearing a location of workpieces, and pre-positioning a workpiece. These are particularly important movements for a workpiece feeding system.

[0030] During emergency procedures, it is stipulated that any movement of the workpiece feeder that has the workpiece processing unit as its source or destination will not be initiated. All movements of the workpiece feeder that do not have the workpiece processing unit as their source or destination will continue without interruption. This takes into account the fact that the workpiece processing unit is typically inoperable during a power outage. Therefore, jobs with a workpiece processing unit as their source or destination will not be started, and the workpiece feeder will not be blocked by such jobs. As soon as the workpiece processing unit is operational again, this can be automatically detected by a control and / or regulating device of the workpiece feeder, and existing jobs can then be executed independently.

[0031] In a further development process, planned but not yet initiated workpiece movements with the workpiece processing unit as the destination are automatically converted into movements to an intermediate storage location, preferably located near the workpiece processing unit. The workpieces are then preferably placed at the intermediate storage location in reverse production sequence. Thus, during a power outage, workpiece movements that are no longer possible are converted into movements that are still possible. This further improves the overall productivity of the workpiece processing system.The intermediate storage location is preferably located near the workpiece processing equipment so that, once the power outage has ended and the workpiece processing equipment has been restarted (e.g., by an operator), the workpieces located in the intermediate storage location can be fed to the workpiece processing equipment in a short time. This mode can also be extended beyond the end of the power outage until the workpiece processing equipment is operational again (e.g., workpieces need to be removed from the workpiece processing equipment, the workpiece processing equipment needs to be rereferenced, etc.).

[0032] During further training, it is stipulated that if a workpiece movement initiated by the workpiece feeder is directed towards the workpiece processing unit before a failure occurs, and the workpiece processing unit is not in a state where it can receive the workpiece, the movement towards the workpiece processing unit is aborted and the workpiece is placed in an intermediate storage location. In this case as well, the intermediate storage location is preferably located near the workpiece processing unit. This measure ensures increased reliability and safety in the operation of the workpiece processing system.

[0033] During further training, it is planned to examine whether a workpiece being processed by the workpiece machining unit at the start of the emergency procedure needs to be provided again by the workpiece feeder or whether processing can continue after the emergency procedure has ended. This can be achieved, for example, by having the workpiece machining unit provide the workpiece feeder with the necessary information independently, even before it is switched off due to the power failure. This allows a new workpiece to be provided by the workpiece feeder, if necessary, even during the power outage, for example, by placing it in an intermediate storage area near the workpiece machining unit. This further accelerates the commissioning of the workpiece machining system after a power failure.

[0034] In summary, the present invention allows for the saving and evaluation of relevant production data and the status of the workpiece processing system after a power outage. Once the power outage begins, a process step that was being executed at the start of the outage is converted into an alternative process step, thereby creating better conditions for resuming operation of the workpiece processing system. For example, in the event of a power outage, a workpiece position, a processing status in a workpiece processing unit, and the entire workpiece processing system itself can be checked against the saved data, and the current process step can be continued or replaced by an alternative process step or steps.

[0035] For example, secured data regarding workpiece position, processing status (e.g., position in a cutting plan of a panel saw), identification of workpieces produced according to a current cutting plan before the power failure, position of a tool of the workpiece processing device at the time of the power failure, position of the workpiece at the time of the power failure, reuse of the workpiece, and completeness of the backup after the power failure can be evaluated.

[0036] The process steps can also be defined based on the capacity of the second electrical power supply. Depending on past power outages (frequency, duration), different actions or scenarios are initiated: for example, if there is a power outage three times a month lasting less than one minute, the current process step or any started movement of a workpiece is completed. Conversely, if there is a power outage, for example, every two weeks lasting at least 15 minutes, the workpiece feeding device is put into a safe state, and the operation of the workpiece processing device is stopped.

[0037] An embodiment of the invention is explained below with reference to the accompanying drawing. This drawing shows: Figure 1 is a schematic representation of a workpiece machining system; and Figure 2 is a flowchart of a method for operating the workpiece machining system. Figure 1 .

[0038] A workpiece machining system contributes to Figure 1 The entire system is designated by reference numeral 10. In this case, it comprises a workpiece machining device 12 and a workpiece feeding device 14. In an embodiment not shown, the workpiece machining system comprises a plurality of workpiece machining devices.

[0039] The workpiece processing device 12 is a device for processing panel-shaped workpieces, such as those used for furniture manufacturing. The workpiece processing device 12 is a panel saw.

[0040] For example, the workpiece feeding device 14 in this case is a so-called "flat storage system." Such a system typically comprises several storage locations for large-format, plate-shaped workpieces and one or more robots, for example, a gantry robot. This robot can, in turn, include a so-called "suction traverse," which is a structure with a plurality of vacuum suction cups. These can grip the top surface of a plate-shaped workpiece, enabling the robot to lift the workpiece, transport it to a specific destination, and place it there.

[0041] In the present example, the workpiece feeding device 14 feeds plate-shaped workpieces to the workpiece processing device 12 (arrow 16 in Figure 1), so that they can be processed there, for example by sawing and cutting them into smaller pieces. The workpiece processing unit 12 is therefore the "destination" of the workpiece feeding unit 14. Furthermore, the workpiece feeding unit 14 can serve to take back workpieces that have only been partially processed by the workpiece processing unit 12 and temporarily store them in a storage location of the workpiece feeding unit 14 ("intermediate storage location") until the temporarily stored workpiece can be fed back to the workpiece processing unit 12 for further processing. In this case, the workpiece processing unit 12 is the "source" of the workpiece feeding unit 14.

[0042] To ensure that no persons are harmed during the operation of the workpiece processing system 10, the workpiece processing system 10 is equipped with a safety device 18. This device may, for example, include a fence with light barriers and access gates. Furthermore, the safety device 18 may include one or more video cameras and / or safety laser scanners that monitor the area of ​​the workpiece processing system 12 and the workpiece feeding system 14 and transmit the signals to an image acquisition and / or image evaluation system. With the aid of the safety device 18, operation of the workpiece processing system 12 and / or the workpiece feeding system 14 can be automatically stopped and / or locked if the safety device 18 detects that a person is in the area of ​​the workpiece processing system 12 and / or the workpiece feeding system 14.In the embodiment shown here, the safety device 18 monitors the entire workpiece processing system 10, i.e., both the workpiece processing device 12 and the workpiece feeding device 14. . In an embodiment not shown, the workpiece processing device and the workpiece feeding device each have separate safety devices. These can then form a common safety zone.

[0043] The operation of the workpiece processing unit 12 is controlled and regulated by a control unit 20. The control unit 20 can be, for example, a computer with a microprocessor, memory, software stored in memory, input devices (e.g., keyboard, mouse, microphone, etc.), and output devices (e.g., screen, speakers, laser pointers, light bar, etc.). Similarly, the operation of the workpiece feeding unit 14 can be controlled and regulated by a control unit 22, which can also be, for example, a computer of the type just described. The two control units 20 and 22 can communicate with each other, so that the workpiece processing unit 12 and the workpiece feeding unit 14 can be operated in a coordinated manner.

[0044] The workpiece processing system 10 also includes a power supply. In this example, this comprises a first electrical power supply unit 24 and a second electrical power supply unit 26. The first electrical power supply unit 24 is the primary electrical power supply unit, as it provides the individual components of the workpiece processing system 10 with the electrical energy necessary for its normal operation. The first electrical power supply unit 24 is typically the public power grid.

[0045] The second electrical power supply unit 26 is the secondary electrical power supply unit, which is only used in the event of a failure of the first electrical power supply unit 24 ("power outage"). For example, the second electrical power supply unit 26 can include an electrical energy storage device, for example in the form of accumulators or rechargeable batteries, and / or an emergency power generator, i.e., for example a generator driven by an internal combustion engine.

[0046] The first electrical power supply unit 24 is preferably connected to the second electrical power supply unit 26, for example, to charge any electrical energy storage devices located there. The first electrical power supply unit 24 is also connected to an input of a dual-feed module 28, which is also connected to the second electrical power supply unit 26. Furthermore, the first electrical power supply unit 24 is directly connected to the workpiece processing unit 12. In this way, during normal operation of the workpiece processing unit 10, the first electrical power supply unit 24 directly ensures the electrical supply to the individual components of the workpiece processing unit 12. These components include, for example, electric motors, electromagnetically controlled valves, etc.

[0047] The dual power supply module 28 is connected on its output side to both the control and regulating unit 20 of the workpiece machining unit 12 and the control and regulating unit 22 of the workpiece feeding unit 14. Furthermore, the safety device 18, as well as the workpiece feeding unit 14 and its individual components, are supplied with electrical energy via the dual power supply module 28. These components are typically electric motors, electromagnetically controlled valves, etc.

[0048] Under normal operating conditions, the dual power supply module 28 receives electrical energy from the first electrical power supply unit 24. In the event of a failure of the first electrical power supply unit 24 (power outage), the dual power supply module 28 receives electrical energy from the second electrical power supply unit 26. In such a power outage, the two control and regulating devices 20 and 22, the safety device 18, and the workpiece feeder 14 can thus continue to be supplied with electrical energy via the second electrical power supply unit 26 and the dual power supply module 28.

[0049] During a power supply failure (power outage) by the second power supply unit 26, predefined emergency procedures are executed. An example of such an emergency procedure is now given with reference to Figure 2 Explained in more detail.

[0050] The in Figure 2The described procedure begins in a start block 30. A function block 32 then checks whether the power supply from the first electrical power supply unit 24 has failed, i.e., whether a power outage has occurred. If the response in function block 32 is "year", the dual feed module 28 is switched to the input side of the second electrical power supply unit 26 in a function block 34, and the second electrical power supply unit 26 is switched on. From this moment on, the two control and regulating devices 20 and 22, the safety device 18, and the workpiece feeder 14 are supplied with electrical energy from the second electrical power supply unit 26, i.e., the "emergency power supply".

[0051] Immediately after the power outage begins, a data backup is initiated in a functional block 36. This means that all current process data in the two control units 20 and 22 are saved in their respective non-volatile memory locations. The current process data includes, for example, relevant production data and the current state of the entire workpiece processing system 10, including a definition of the "active orders" of the workpiece feeder 14 and the workpiece processing unit 12 at the beginning of the power outage.

[0052] The stored process data can be used to take immediately necessary measures and / or to adapt or enable further operation, at least of the workpiece feeding device 14. Likewise, the stored process data can later be used to restart the workpiece processing device 12 in a controlled and rapid manner. Preferably, the control unit 20 of the workpiece processing device 12 is shut down in a controlled manner within the functional block 36. This results in the workpiece processing device 12 no longer being operational. Furthermore, it is possible to bring the workpiece processing device to a safe state in a controlled manner and switch it to a standby mode in order to restart it as quickly as possible after the power outage.

[0053] Functional block 38 ensures that the safety device 18 remains operational. As in connection with Figure 1 As explained, this is ensured, among other things, by the fact that the safety device 18 is supplied with electrical energy by the dual power supply module 28. Advantageously, the safety device 18 has its own control and regulating unit (not shown here). If, as will be shown below, the workpiece feeder 14 continues to operate even during a power outage, the continued operation of the safety device 18 nevertheless ensures that no persons are in the vicinity of the workpiece feeder 14 and can be harmed there.

[0054] In a function block 40, the expected duration of the failure of the first electrical power supply unit 24 is retrieved. This expected duration is provided in a function block 42. The expected duration of the power outage is determined based on historical data provided in a function block 44. The historical data in function block 44, in turn, is based on power outages that occurred in the past (function block 46) and can include the durations and times of these outages, as well as other accompanying circumstances. For example, the frequency and duration of power outages that occurred during the operation of the workpiece processing system 10 in the past may have been recorded and stored as the aforementioned "historical" data in function block 44.

[0055] The expected duration can be determined in the simplest case within function block 42 by calculating the arithmetic mean of the durations of past outages. However, other parameters can be considered when determining the expected duration of the power outage. For example, the time of day and / or the day of the week can influence the expected duration of the power outage. For instance, longer power outages may be more likely on certain days of the week and / or at certain times of day, while shorter outages are more likely on other days of the week and / or at other times of day. This can also be taken into account in function block 42.

[0056] In a comparison block 48, it is checked whether the expected duration of the power outage retrieved in function block 40 is less than a threshold value. If this is not the case (answer "No"), a first variant of an emergency procedure is initiated in function block 50. If, on the other hand, the retrieved expected duration of the power outage is less than the threshold value (answer "Yes"), a second variant of an emergency procedure is initiated in function block 52.

[0057] The limit value can be fixed, for example, depending on the maximum capacity of the second electrical power supply unit 26. The limit value can also be set by the operator of the workpiece processing system 10, depending on the individual configuration of the workpiece processing system 10. The specific content of the two emergency procedures 50 and 52 can also be individually defined by the operator.

[0058] However, it is also possible that the current storage level of the second electrical power supply unit 26 is used as a parameter to define the limit value. This can ensure that, when the storage level of the second electrical power supply unit 26 is low, a safer variant of an emergency procedure is initiated more frequently. This is in Figure 2 This is indicated by a functional block 53, which feeds the current storage fill level as a parameter into the comparison block 48. In this case, two conditions are checked in the comparison block 48: a ratio between the expected duration of the power outage and a limit value, and a ratio between the current fill level of the second electrical power supply device 26 and a limit value.

[0059] The storage level provided in function block 53 can be used not only to define the limit value in comparison block 48, but also at numerous other points during the two emergency procedures 50 and 52. This is indicated by dashed arrows emanating from function block 53. For example, before safety-relevant process steps, or even before any process step in which a workpiece is handled, it can be checked whether the storage level of the second electrical power supply unit 26 is sufficient to execute and complete the process step. Thus, the anticipated energy requirement for executing a process step is compared with the energy still available in the second electrical power supply unit 26.

[0060] Only if it is determined that the storage capacity is sufficient to execute and complete the planned process step (possibly with a certain safety buffer) will the process step even be started. If, on the other hand, it is determined that the storage capacity is insufficient or not reliably sufficient to execute the planned process step, either a different, less energy-intensive process step is planned, or the workpiece processing system 10 or the affected section, for example, the workpiece processing unit 12 and / or the workpiece feeding unit 14, is brought into a safe operating state. For example, a workpiece that has already been picked up is placed in a safe location. The first variant (function block 50) of the emergency procedure is therefore executed when the expected duration of the power outage is relatively long.The second variant (function block 52) of the emergency procedure, on the other hand, is executed when the expected duration of the power outage is relatively short. A typical value for a short power outage duration is in the range of a few minutes, particularly in the range of 1-5 minutes. A typical value for a long power outage duration is in the range of approximately 15 minutes or more. For example, the threshold could be set at 6 minutes.

[0061] The two emergency procedures differ in at least one parameter. In the case of the one in Figure 2In the method shown, at least one parameter characterizing the specified emergency procedure (functional blocks 50 and 52) depends on the expected duration of the failure of the first electrical power supply unit 24. As will be shown below, the emergency procedures can differ in a wide variety of parameters. These parameters include: the position of a process step performed by the workpiece processing system within a series of several process steps; the number of process steps performed by the workpiece processing system; the speed and / or speed profile (acceleration) of the execution of at least one process step performed by the workpiece processing system; and the duration of at least one process step performed by the workpiece processing system.

[0062] In the first variant of the emergency procedure, which is initiated in function block 50, a function block 54 is used to terminate a workpiece movement initiated by the workpiece feeder 14 before the power failure and continuing during the power failure. This is achieved by a controlled placement of the workpiece, for example, in an intermediate storage location. For instance, shortly before the power failure began, the workpiece feeder 14 might have just lifted a flat workpiece from a storage location to feed it to the workpiece processing unit 10. In this case, the workpiece could simply be lowered again and returned to its storage location after the power failure began. However, it is also possible that the workpiece feeder 14 is in the process of moving a large workpiece, which has already been lifted, towards the workpiece processing unit 12 when the power failure begins.In this case, arrangements could be made to place the workpiece at the nearest intermediate storage location.

[0063] When all movements of the workpiece feeder 14 in block 54 have ceased, the workpiece feeder 14 is placed in an energy-saving state in a functional block 56. In such a state, for example, a compressor that normally provides the vacuum at the suction cups of the suction traverse may be switched off. Lighting and display devices may also be switched off. Preferably, only the control and regulating device 22 continues to operate, preferably only in a standby state from which it can be very quickly returned to its normal operating state when the power failure ends. The first variant of the emergency procedure 50 finally ends in a final block 76.

[0064] In the second variant of an emergency procedure corresponding to function block 52, the workpiece feeding device 14 continues to operate to a limited extent. For this purpose, a function block 58 first checks whether a workpiece movement present at the beginning of the power failure is directed towards the workpiece processing device 12. If the answer is "yes," the workpiece is placed in an intermediate storage location in a function block 60, since the workpiece processing device 12 is shut down due to the power failure. In an embodiment not shown, it is also checked whether the workpiece processing device 12 is in a state in which the workpiece can be placed on it despite the workpiece processing device 12 being shut down. This would be the case, for example, if a feed table of the workpiece processing device 12 is free.In this case, the workpiece could be fed to the workpiece processing device 12 and placed there.

[0065] If the answer in function block 58 is "No", the workpiece movement continues as planned through the workpiece feeder 14 (function block 62). Then, in function block 64, it is checked whether a workpiece movement to be carried out after the start of the power failure is directed towards the workpiece processing unit 12. If the answer is "No", the workpiece movement is carried out as planned in function block 66. If, however, the answer is "Yes", the planned movement is converted in function block 68 into a movement to an intermediate storage location. Preferably, the intermediate storage location is near the workpiece processing unit 12.

[0066] Further planned movements of workpieces of this kind are also carried out and converted into movements to this intermediate storage location. The movements are preferably rearranged so that the workpieces are placed at the intermediate storage location in reverse production sequence. After the power outage ends and the workpiece processing unit 12 is restarted, the uppermost workpiece on the stack of workpieces located at the intermediate storage location is thus the first workpiece to be fed to the workpiece processing unit 12 according to the intended processing plan.

[0067] Subsequently, in function block 70, it is checked whether the power failure occurred during the machining of a workpiece by the workpiece machining unit 12, thus preventing the completion of the machining of that workpiece. If the answer to the query is "Yes," function block 72 checks whether a machining plan needs to be adjusted as a result. This is the case, for example, if the interruption of machining renders the workpiece currently being machined or produced unusable. It must therefore be reproduced. If this is the case (result of the query in function block 72 = "Yes"), the machining plan is automatically adjusted in function block 74 so that the corresponding workpiece can be reproduced after the power failure ends and the workpiece machining unit 12 is restarted.

[0068] In particular, during the execution of the emergency procedure according to functional block 52, it is continuously checked whether sufficient electrical energy can still be provided by the second electrical power supply unit 26 for the next procedure step to be carried out.If it is determined that the electrical energy that the second electrical power supply unit 26 can provide is running low, the operation of the workpiece feeding device 14 is terminated in a controlled manner by either only carrying out the next planned handling step or only carrying out another handling step possible with the available energy and then stopping operation, or by stopping operation before the start of the next actually planned handling step if the energy that can be provided by the second electrical power supply unit 26 is no longer sufficient for any further handling step.This is indicated by a dashed box with reference numeral 73, which encloses function blocks 60-74 and from which a transverse jump leads to function block 56 (thus, a jump to function block 56 can be made before each of the function blocks 60-74 of the second emergency procedure 52). The second emergency procedure according to function block 52 can therefore be carried out until the second electrical power supply unit 26 can no longer provide the energy necessary for further operations. The control unit 22 can then also be shut down in a controlled manner and, for example, put into a standby state. This was similarly described above in connection with function block 53.

[0069] Furthermore, in the second emergency procedure according to functional block 52, the workpiece feeder 14 can be operated in a particularly energy-efficient manner. For example, the movements of workpieces can be slowed down by the workpiece feeder 14, and both positive and negative accelerations at the beginning and end of workpiece movements can be reduced. The weight of the workpiece to be moved can also be taken into account.

[0070] Both emergency procedures corresponding to functional blocks 56 and 58 end in a final block 76.

[0071] At the end of a cycle, for example, a completed movement of the workpiece feeder 14, a check is performed in function block 75 to see if the first electrical power supply unit 24 is available again, i.e., if the power outage has ended. If this is the case (answer "Yes"), the process ends in the aforementioned end block 76, and the workpiece processing system 10 can, for example, return to normal operation. If, however, the power outage continues (answer "No"), the process jumps back to before function block 40, where the expected duration of the power outage is retrieved again. Function block 48 then decides whether the first variant of the emergency procedure in function block 50 or the second variant of the emergency procedure in function block 52 should be carried out. .The current memory fill level can also be retrieved again in function block 53, and the logic already described above in connection with function block 53 can be executed.

[0072] It is understood that the above procedure is merely an example. In other embodiments not shown or described, the emergency procedures may differ in terms of parameters and process steps. However, it is evident from the exemplary procedure that the control unit 22 of the workpiece feeder 14 reacts dynamically to a power failure, depending on the process data (current process step, source, destination, type of order). Continuous and intelligent optimization takes place based on the number and duration of power failures, the capacity of the secondary electrical power supply 26, and the power requirements of the workpiece feeder 14.If the capacity of the second electrical power supply unit 26 reaches a critical level during an impending power outage, the shutdown of the control and regulation unit 22 is triggered in any case, including at the workpiece feed unit 14, in order to avoid database inconsistency.

[0073] Typically, at the beginning of a power outage, workpieces picked up by the workpiece feeder 14 and destined for the workpiece processing unit 12 are moved there if possible. At the latest after this point, however, the workpiece processing unit 12 is blocked as a destination. Possible workpiece movements, such as storage and transfer operations, continue to be carried out essentially without restriction. Workpiece movements that are no longer possible, such as removal to the workpiece processing unit 12, are replaced by other possible movements, such as temporary storage at intermediate storage locations. Depending on the recorded historical data and the expected duration of the power outage, the workpiece feeder 14 can cease operation and switch to standby mode after a certain maximum number of workpiece movements.

[0074] It is understood that after the power outage ends, the workpiece feeder 14 can resume operation independently and without operator intervention. However, the workpiece feeder 14 usually needs to be manually reset to a production-ready state.

Claims

1. Method for operating a workpiece processing system (10) comprising a workpiece processing device in the form of a panel saw for dividing large-format panels and a workpiece feeding device, in which, in the event of a failure of a first electrical power supply device (24), electrical power is provided at least temporarily by a second electrical power supply device (26), and in which, while electrical power is supplied in this way by the second power supply device (26), a predetermined emergency procedure is executed, wherein at least one parameter characterizing the predetermined emergency procedure depends on an expected duration of the failure of the first electrical power supply device (24), and wherein the parameter characterizing the predetermined emergency procedure is at least one from the following group: position of a method step performed by the workpiece processing system in a series of multiple method steps, number of method steps performed by the workpiece processing system, speed and / or speed profile of the execution of at least one method step performed by the workpiece processing system, duration of at least one method step performed by the workpiece processing system.

2. Method according to claim 1, characterized in that the emergency procedure comprises: providing electrical power through the second power supply device (26) to a safety device (18) of the workpiece processing system (10).

3. Method according to at least one of the preceding claims, characterized in that an expected duration of the failure of the first electrical power supply (24) is determined on the basis of historical data.

4. Method according to at least one of the preceding claims, characterized in that the workpiece processing system (10) comprises at least one workpiece processing device (12) for processing workpieces and a workpiece feeding device (14) for feeding workpieces to the workpiece processing device (12), and in that in the event of an expected first and comparatively long duration of the failure of the first electrical power supply (24), the emergency procedure comprises: terminating a movement of a workpiece by the workpiece feeding device (14), preferably that started before the failure, by means of a controlled placement of the workpiece.

5. Method according to claim 4, characterized in that the emergency procedure comprises: putting the workpiece feeding device (14) into an power-saving state after the controlled placement of the workpiece.

6. Method according to at least one of the preceding claims, characterized in that the workpiece processing system (10) comprises at least one workpiece processing device (12) for processing workpieces and a workpiece feeding device (14) for feeding workpieces to the workpiece processing device (12), and in that in the event of an expected second and comparatively short duration of the failure of the first electrical power supply (24), the emergency procedure comprises: continuing a movement of a workpiece by the workpiece feeding device (14) that was started before the failure and does not have the workpiece processing device (12) as its source or destination as intended before the failure.

7. Method according to claim 6, characterized in that at least one movement of the workpiece feeding device (14) to be started during the emergency procedure is performed at least substantially unchanged.

8. Method according to claim 7, characterized in that the movement of the workpiece feeding device (14) is one from the following group: storing a workpiece, repositioning a workpiece, clearing a location of workpieces, pre-storing a workpiece.

9. Method according to at least one of claims 6-8, in that a movement of the workpiece feeding device (14) which has the workpiece processing device (12) as its source or as its destination is not started during the emergency procedure.

10. Method according to at least one of claims 6-9, characterized in that intended and not yet started movements of workpieces with the workpiece processing device (12) as the destination are automatically converted into movements to an intermediate storage location preferably arranged near the workpiece processing device (12), the workpieces preferably being placed at the intermediate storage location in reverse production sequence, and / or are converted into a movement of the workpiece feeding device (14) which is one from the following group: storing a workpiece, repositioning a workpiece, clearing a location of workpieces, pre-storing a workpiece.

11. Method according to at least one of claims 4-10, characterized in that in the event that a movement of a workpiece by the workpiece feeding device (14) that started before the failure has the workpiece processing device (12) as its destination and the workpiece processing device (12) is not in a state in which it can receive the workpiece, the movement toward the workpiece processing device (12) as its destination is aborted and the workpiece is placed on an intermediate storage location.

12. Method according to at least one of claims 4-11, characterized in that it is checked whether a workpiece that was being processed by the workpiece processing device (10) at the start of the emergency procedure needs to be provided again by the workpiece feeding device (14) or whether the workpiece can be processed further after the end of the emergency procedure.

13. Workpiece processing system (10), comprising a workpiece processing device in the form of a panel saw for dividing large-format panels, a workpiece feeding device, a first electrical power supply device (24) and a second electrical power supply device (26) which provides electrical power at least temporarily in the event of a failure of the first electrical power supply (24), characterized in that the system comprises an open-loop and / or closed-loop control device (20, 22) which is programmed to execute a method according to any of the preceding claims.