METHOD AND MANUFACTURING PLANT FOR PRODUCING A BENDING PART WITH LIVE ADJUSTMENT OF GEOMETRY

Abstract

The invention relates to a method (1) for manufacturing a bent part. In this method, a sequence of several bending operations (B1, B2, B3) is performed on a workpiece (2) using a bending machine to achieve a predetermined target geometry (3). During this process, the actual geometry (3) of the workpiece (2) is monitored. If a deviation from the target geometry (3) is detected, at least one correction value (W3k) is automatically determined for at least one unexecuted bending operation (B3) to at least partially compensate for the effect of the detected deviation, and the sequence is adjusted accordingly. The remaining unexecuted portion (B3) of the adjusted sequence is then executed to ultimately produce the bent part. The invention also relates to a correspondingly configured production system.

Description

Technical field

[0001] The present invention lies in the field of manufacturing technology and relates to a method for producing a bent part and a correspondingly equipped manufacturing plant. State of the art

[0002] Bending, for example rotary draw bending, is a manufacturing process used for various applications. In this process, multiple bends can be sequentially created on a workpiece using a bending machine. However, errors or deviations from the desired target result can occur, or suitable parameters for the production process, the bending machine, or the corresponding machine control system must first be determined for a new bent part. Currently, this is typically achieved by first producing a bent part, then placing it in a measuring cell and measuring its geometry. If deviations from the desired target result are found, correction values ​​can be determined, and a new bent part can be produced accordingly. In this way, the production process can be optimized iteratively.

[0003] A disadvantage can be that this initially produces rejects and the process can be relatively lengthy and costly in terms of materials and expenses. Description of the invention

[0004] The purpose of the invention is to enable a particularly efficient and low-waste production of bent parts.

[0005] This problem is solved by the subject matter of the main claim and the dependent claim or independent claims. Further possible embodiments of the invention are disclosed in the dependent claims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0006] The method according to the invention can be used in or for the production of a bent part, i.e., a component or workpiece that is bent, particularly multiple times, or manufactured using a bending process, i.e., a bending manufacturing method. In particular, this can be a rotary draw bending process. The bent part can therefore be a rotary draw bending part. The bent part can, for example, be a hollow or solid bar, particularly with a cross-section that is at least substantially round or rectangular. In the method according to the invention, a target geometry for the bent part is specified or a specified target geometry for the bent part is detected, particularly automatically or semi-automatically. The target geometry can, for example, be received via an input interface of a corresponding bending machine or a control unit for controlling a bending machine, or loaded from a computer-readable data storage device.In a further step of the inventive process, a sequence of several bending operations is then performed automatically or semi-automatically on a prepared workpiece using a bending machine to achieve the desired geometry. In other words, the workpiece is bent multiple times, particularly at several different points, using the bending machine to achieve the desired geometry. The respective workpiece may, for example, have been prepared beforehand or be positioned in the bending machine as part of the process.

[0007] The sequence can specify, for example, the bends to be produced, the bending operations to be performed, or corresponding machine or bending parameters, as well as their order or chronological sequence of execution. The machine or bending parameters can specify the bends, for example, with regard to angle (i.e., bending direction and circumference) or their position along the workpiece. Likewise, the sequence or the machine or bending parameters can contain or specify further requirements, such as a bending speed, waiting times to be observed between or during the bending operations, additional processing steps to be applied or performed, and / or the like.

[0008] According to the invention, during the process—that is, while the sequence is being executed or the bending operations are being carried out and the workpiece is thus being processed in the bending machine—the actual geometry of the workpiece is automatically monitored and compared with the target geometry. For example, the actual geometry of the workpiece, or at least of a currently, most recently, or previously processed section of the workpiece, can be continuously recorded or determined before and / or after each bending operation. This can be achieved using appropriate sensors. These sensors can be located in the vicinity of the bending machine, for example, on, beside, or above it. Such sensors can detect the actual geometry of the workpiece, particularly without contact, for example, optically.

[0009] The target geometry can, for example, specify only the ultimately desired final geometry of the bent part. In this case, only the actual geometry of the part already processed or up to the start of the next bend can be compared with the target geometry. Similarly, an expected actual geometry can be determined, which would result from the current processing stage or state of the workpiece assuming correct execution of the remaining bending operations, and this can be compared with the target geometry. Likewise, the target geometry can specify an intermediate target geometry for each state or intermediate state of the workpiece that arises during processing before and / or after a bending operation.In this case, the current actual geometry can then be compared with the intermediate target geometry corresponding to the respective processing stage or processing step.

[0010] If a deviation of the actual geometry from the target geometry is detected, in a further process step of the method according to the invention, at least one correction value or correction factor is automatically determined or calculated for at least one bending operation in the sequence that has not yet been executed, i.e., for at least one bending operation following the current or most recently executed bending operation in the sequence, or for a corresponding machine or bending parameter, in order to at least partially compensate for the effect of the detected deviation. The sequence, i.e., for example, the machine or bending parameters specified therein, are then automatically adjusted accordingly.

[0011] One consequence of a detected deviation can be, for example, a deviation of the workpiece from the target geometry at a subsequent point or in an unprocessed section of the workpiece, which is at least foreseeable or, for example, would result from the assumption that the subsequent bending operations are executed correctly. For instance, a consequence of a deviation—that is, a bend that is not executed or produced correctly or as intended—in a front or middle area of ​​the workpiece can be that, ultimately, after completion of the manufacturing process, a distal end of the workpiece is not located at a spatial point specified by the target geometry, nor in a position or pose relative to the beginning of the workpiece or the bent part subsequently produced from it, as specified by the target geometry.Similarly, an effect of a deviation may be, for example, that the final bent part then deviates from the target geometry at one or more points or in one or more sections, in particular by more than a specified permissible tolerance, or has, for example, an incorrect shape or the like.

[0012] To adjust the sequence, for example, at least one correction value can be added to or multiplied by at least one or the respective bending angle provided for in the original or previously used sequence, resulting in a corrected, i.e., appropriately adjusted bending angle and thus also an appropriately corrected or adjusted sequence or residual sequence.

[0013] In a further step of the process according to the invention, any remaining, unexecuted portion of the correspondingly adapted sequence of bending operations, or at least one unexecuted bending operation, is then carried out to produce the bent part or to complete its production. The comparison of the actual geometry with the target geometry, the corresponding determination of at least one correction value, and the adjustment of the sequence accordingly can be performed multiple times during the production of the bent part. In other words, the sequence can be adjusted multiple times during production. The sequence used most recently—that is, initially the originally specified sequence and subsequently the sequence most recently adjusted—can be used as the basis for each subsequent adjustment.This can ultimately result in a fully adapted or optimized sequence of bending processes for producing the bent part according to the target geometry or at least with the maximum permissible deviations from it.

[0014] The present invention enables live or real-time adjustment during manufacturing. Thus, the present invention, or a corresponding algorithm, allows, for example, bending angle deviations of a workpiece to be compensated for on the same workpiece during manufacturing, without rendering the workpiece scrap. This can prevent scrap and therefore save time, material, and costs, and increase productivity, particularly in the prototype stage or during development. The present invention can, for example, accelerate or shorten the process of optimizing the manufacturing process or the sequence of bending operations for producing a new bent part, thereby reducing time, material, and cost expenditure.The present invention thus significantly reduces the workload for new geometries and tolerances compared to conventional methods, in which the adjustment of bending parameters is performed iteratively with or after each complete production of a bent part. Furthermore, the present invention can specifically address and compensate for effects occurring during the actual processing of the workpiece in the bending machine. In contrast, conventional approaches may not be able to distinguish between geometric deviations occurring during the actual processing in the bending machine and geometric deviations resulting from transferring the produced bent part to a measuring cell or from intermediate storage or handling of the bent part, i.e., additional deformations.This means that the present invention can enable or support the particularly efficient and precise production of bent parts.

[0015] In one possible embodiment of the present invention, the actual geometry is monitored using a laser. The workpiece, or rather its actual geometry, can thus be detected by means of a laser or a suitably configured laser device. This enables non-contact, precise, and consistent detection and monitoring of the actual geometry. This avoids influencing the workpiece during the measurement process to detect the actual geometry and thus preventing the measurement result from being distorted. Furthermore, laser-based detection of the actual geometry is particularly fast, so that interruptions during production can be avoided or minimized, and overall, a particularly high manufacturing efficiency can be achieved.

[0016] In a further possible embodiment of the present invention, monitoring the actual geometry includes monitoring the bending angle. In other words, for example, the bending angle produced during or in the immediately preceding bending process can be monitored or recorded when monitoring the actual geometry. The bending angle can be a significant factor with regard to the production and geometry of bent parts. Thus, monitoring the bending angle can be particularly relevant and informative for determining whether the actual geometry corresponds to the target geometry.

[0017] In a further possible embodiment of the present invention, monitoring the actual geometry includes monitoring free lengths of the workpiece and / or the position or pose of an end of the workpiece. Free lengths are, in this context, straight sections or segments of the workpiece before and / or after one or more bends. The free lengths can be determined, for example, from a given bending angle and machine parameters, i.e., settings, operating or control parameters, or measured actual movements of the bending machine. Likewise, the free lengths can be measured directly on the workpiece, for example, using appropriate sensors, particularly non-contact sensors.The position or pose of the workpiece end can be monitored, for example, its current actual position, either absolutely in space or relative to a predefined reference point or geometry, such as a fixed bending machine, and / or relative to a remaining part or a starting point, such as the opposite end of the workpiece. Similarly, the position or pose of the workpiece end can be monitored as expected after the sequence is completed. This can be based on the assumption that the remaining bending operations, i.e., those not yet executed, will be carried out correctly, as specified in the sequence (which may have been adjusted). Furthermore, any detected systematic errors can be taken into account and factored in.Such errors, for example, deviations of the actual bending angles from the corresponding specifications according to the target geometry, can arise due to wear or misalignment of the bending machine, due to the properties of the workpiece, due to current environmental conditions, or similar factors. The monitoring of the free lengths and / or the position or pose of the workpiece end, as proposed here, can, especially in addition to the bending angle monitoring mentioned elsewhere, enable particularly precise monitoring of the actual geometry and thus a highly reliable detection of deviations from the target geometry.

[0018] In a further possible embodiment of the present invention, during the execution of the sequence of bending operations, i.e., during the production of the bent part, it is monitored whether the target geometry, including specified tolerances, can at least be expected to be achieved or realized, i.e., whether the specified tolerances can still be maintained. The specified tolerances, i.e., permissible deviations from the target geometry, can be specified, for example, in the form of an envelope or boundary that surrounds the target geometry.To determine whether the target geometry, including specified tolerances, can still be achieved or maintained—for example, whether the actual geometry of the workpiece after completion of the bending sequence is expected to lie entirely within the envelope—the expected final geometry of the workpiece can be extrapolated or modeled based on the current actual geometry. This can take into account specific correction values, i.e., adjustments already made to the originally specified bending sequence. Likewise, potential future correction values ​​or adjustments, such as the technical capabilities or the corresponding parameter space of the bending machine, can be considered.

[0019] If it is detected that the target geometry, including tolerances, cannot be achieved or maintained, the production of the respective bent part, i.e., the corresponding processing of the workpiece, is automatically aborted. For example, the workpiece can then be issued in an unfinished state, i.e., before all bending operations specified in the sequence or provided for in the sequence have been carried out. The workpiece can then be declared as scrap. With the embodiment of the present invention proposed here, unavoidable scrap can be detected during production. In such a case, the premature termination of production or processing can save time and effort. This can also benefit production efficiency, particularly in the mass production of bent parts.

[0020] In another possible embodiment of the present invention, the target geometry specifies an ideal shape of the bent part. Additionally, a predetermined envelope surrounding the target geometry is defined, as mentioned elsewhere, which specifies a permissible tolerance, i.e., a permissible deviation of the actual geometry from the target geometry. For example, the target geometry can be a center line of the envelope. Likewise, different tolerances, i.e., different distances of the envelope from the target geometry, can be possible or specified depending on the direction. Furthermore, a predetermined engagement limit is defined, which at any point along the target geometry deviates from the target geometry by no more than the envelope, and in particular, by less than the envelope.For example, the envelope might surround the target geometry at a distance of 5 mm, while the intervention limit might be only 3 mm away. In such cases, if a deviation of the actual geometry from the target geometry is detected, a correction value is only determined or calculated if the deviation is at least as large as the deviation of the intervention limit from the target geometry. Specifically, the correction value can only be determined if the deviation is no larger than the deviation of the envelope from the target geometry. If the deviation is larger, production can be aborted, and the workpiece can be rejected as unfinished or scrap, similar to the process described elsewhere.If, however, the deviation is smaller than the difference between the intervention limit and the target geometry, processing can continue as planned, i.e., without adjusting the sequence. This avoids the time and effort required for determining correction values, adjusting the sequence, and controlling the bending machine, which is ultimately unnecessary. This can save time and money.

[0021] In a possible further development of the present invention, the production of the bent part, i.e., the processing of the respective workpiece, is automatically terminated if, after the complete completion of a bending operation, i.e., after the production of a bend, the actual geometry lies outside the envelope at at least one point before the start of the next bend to be produced. In particular, in this case, the determination of a correction value can also be dispensed with. The complete completion of a bending operation can, for example, also include post-processing of the current or the last produced bend, as mentioned elsewhere. Although the present invention is based on the idea of ​​compensating for a deviation from the target geometry that occurred during the production of a specific bend by adjusting subsequent bending operations, it can therefore be specified that the workpiece or theThe corresponding bent part must ultimately adhere to the specified tolerances at every point, i.e., lie within the envelope. If this is not the case after completion of a particular bend, especially in the area or section of that bend—for example, between the positions of the bends adjacent or nearest in both or all directions along the workpiece—this cannot be compensated for by adjusting the remaining bending operations. This can apply at least if the remaining sequence of bending operations does not involve machining the workpiece in the area of ​​the currently completed bend or the bend immediately preceding it. Otherwise, a corresponding correction value can be determined, and production can continue. The premature adjustment proposed here, i.e., before completion of production, is therefore not possible.By interrupting the production process before the sequence of bending operations is fully executed, additional time and processing effort can be saved for a workpiece that would otherwise be scrapped. This can further improve production efficiency, especially in the mass production of bent parts.

[0022] In a further possible embodiment of the present invention, if a deviation of the actual geometry from the target geometry is detected, it is determined before the next bending operation whether the target geometry, including specified tolerances, can still be achieved or maintained, in particular solely by one or at least one correction value, i.e., by adjusting the subsequent bending operations. Then, and in particular only if this is not the case, it is determined whether achieving or maintaining the target geometry, including specified tolerances, is at least likely to be possible by reworking the current bend or the bend that was last produced or started. Then, and in particular only if this is the case, a corresponding reworking is carried out, and the actual geometry achieved is again measured and compared with the target geometry.Here, the current, last executed, or last started bending process can be repeated or modified and then executed again in its modified form. While this may require additional time compared to the originally intended adjustment of subsequent bending processes to compensate for detected deviations, it can potentially prevent scrap. Furthermore, since the proposed rework takes place during the manufacturing of the respective component, i.e., within the sequence of bending processes, the additional time required can be minimized, for example, compared to post-processing the manufactured bent part after completion of the bending sequence, as the latter can require additional effort for handling the bent part.By avoiding otherwise occurring scrap, as enabled by the proposed embodiment of the present invention, greater overall efficiency in the production of, in particular, a large number of bent parts can ultimately be achieved or enabled, despite the additional time required for rework. In principle, reworking or re-bending the current or most recently produced bend can only be considered if compensating for the detected deviation is not possible by adjusting subsequent bending processes, in order to enable the fastest possible production of the bent part and thus avoid delays caused by rework.

[0023] In another possible embodiment of the present invention, the bent part is a busbar, particularly for a motor vehicle. Such a busbar can be designed, for example, as a flat-edged profile or tube, or as a solid round profile. The initial workpiece can be, for example, an already electrically insulated conductor material, or, after completion of the sequence of bending operations, i.e., after all bending operations have been carried out, the resulting electrically conductive bent part can be electrically insulated to ultimately produce a busbar that is at least partially electrically insulated. Busbars are often required in large quantities, for example in motor vehicle manufacturing, so the efficiency gains in production made possible by the present invention can be particularly effective in this context.For example, the conductor rail produced here can be intended for a drive system of an electric, in particular battery-electric, motor vehicle, and thus designed accordingly.

[0024] The present invention also relates to a production plant for manufacturing bent parts. The production plant according to the invention comprises a bending machine for bending workpieces, a detection and monitoring device for detecting and monitoring the actual geometry of each workpiece being processed during its processing, i.e., during the production of the respective bent part, and a control unit coupled to the detection and monitoring device. This control unit is configured to compare the actual geometry with a target geometry specified for the respective bent part and, if necessary, to determine correction values ​​for subsequent bending operations of the workpiece and to control the bending machine accordingly. According to the invention, the production plant as a whole is configured for carrying out the method according to the invention, in particular automatically or semi-automatically.The manufacturing system, in particular the control unit, can, for example, include a process unit, such as a microchip, microprocessor, microcontroller, or the like, and a computer-readable data storage device coupled to it. This data storage device can then contain a corresponding operating or computer program that encodes or implements the process steps, measures, or sequences mentioned in connection with the method according to the invention, or corresponding control instructions. This operating or computer program can then be executed by means of the process unit in order to carry out the corresponding method or to effect its execution.

[0025] The control unit can, for example, be part of the bending machine or connected or coupled to it for its control. Similarly, the production system, and in particular the control unit, can have an input interface for capturing order or input data. This data can include, for example, the target geometry, especially including permissible tolerances, or data specifying these tolerances, or data specifying permissible adjustments, such as the technical capabilities of the bending machine, minimum and maximum values ​​of the machine or bending parameters, corresponding load limits of the workpiece, or similar information.

[0026] Further advantages, features, and details of the invention may become apparent from the following description of possible embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as those shown below in the figure description and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention. Brief character description

[0027] The drawing shows in: Fig. 1. An exemplary schematic flowchart to illustrate a process for manufacturing a bent part with real-time geometry correction; and Fig. 2 a schematic representation of a workpiece with target geometry (3), actual geometry and corrected geometry.

[0028] Fig. Figure 1 shows an exemplary flowchart 1 to illustrate a process for manufacturing bent parts. In process step S1, order or input data for the production of the respective bent part can be provided or recorded, and a workpiece 2 (see Figure 1) can be generated. Fig. 2) can be provided as a starting point. For example, workpiece 2 can be positioned here in a bending machine.

[0029] In process step S2, it can be checked whether a predefined sequence of bending operations, or one automatically determined based on the provided data, has been completed. If so, the finished bent part can be output in process step S3. However, if process step S2 detects that the sequence has not yet been completed, meaning at least one more bending operation is required, the next bending operation in the sequence can be executed in process step S4, i.e., the next bend of workpiece 2 can be produced.

[0030] In a process step S5, the achieved actual geometry 5 (see Fig. 2) of the workpiece 2 with a specified target geometry 3 (see Fig. 2) of the bent part to be produced. If the actual geometry 5 corresponds to the target geometry 3 or if a detected deviation is smaller than a predefined intervention limit, the process can jump back to process step S2.

[0031] If, however, a deviation of the actual geometry 5 from the target geometry 3 is detected in process step S5, particularly to an extent exceeding the specified intervention limit, then process step S6 can be used to check whether this deviation can be corrected by adjusting subsequent bending operations that have not yet been performed, so that the specified target geometry 3, including specified tolerances, can at least be achieved or maintained. If this is the case, then – either in process step S6 or in a subsequent process step S7 – at least one corresponding correction value can be determined. In process step S7, this correction value can be applied to the sequence used so far, thus adjusting at least one bending operation yet to be performed or a corresponding parameterization or control setting for the bending machine.Similarly, several different correction values ​​can be determined for various bending operations yet to be performed, and these bending operations can then be adjusted with the respective individual correction value. The process can then jump back to process step S2 and continue from there, using the adjusted sequence.

[0032] If, in process step S6, it is determined that compensating for a detected deviation by adjusting subsequent bending operations is not possible, or at least not likely to be possible, the process can jump to process step S8. In process step S8, it can be determined whether the detected deviation can be at least partially compensated, or at least sufficiently compensated, by re-creating (i.e., reworking) the current or last produced bend, so that the specified tolerances—i.e., the permissible deviations from the target geometry 3—can be met, possibly taking future correction values ​​into account. If this is not the case, production can be aborted in process step S9 and workpiece 2 can be rejected as scrap. If, however, it is determined in process step S8 that a correction by reworking or...If re-bending is possible, this reworking or re-bending is carried out in process step S10. The process can then jump back to process step S2 and continue from there.

[0033] According to the method or algorithm described here, if, for example, certain bending angles deviate from a given target bending angle, subsequent bending operations or later produced bends can be manipulated using a correction value or correction factor to comply with the specified tolerances or, for example, to achieve conformity between the final actual geometry 5 and the target geometry 3 at certain predefined key positions. This allows for intelligent improvement within the permissible tolerances, such as adjustments to the envelope surrounding the target geometry 3 during manufacturing. This enables, for example, a dynamic response to changing parameters in the production batch. The method enabled here...The described optimization of bending geometries during the bending process, i.e., during manufacturing, in order to produce the target geometry 3 within the specified tolerances, can enable a reduction or avoidance of scrap and a saving of material, especially in a prototype phase.

[0034] To further illustrate this, shows Fig.Figure 2 shows a schematic representation of workpiece 2 in a simplified 2D form. According to the target geometry 3, indicated by dashed lines, a first bend B1, a second bend B2, and a third bend B3 can be provided. For the first bend B1, a first target bending angle W1s of 90° in the xy-plane is specified. The second bend B2 is to be a rotation or torsion of 90° about the x-axis. For the third bend B3, a third target bending angle W3s of also 90° is specified. According to the specified sequence of bending operations, the bends B1, B2, and B3 are to be executed in the order mentioned.

[0035] As an example, consider the situation where, during the production of the first bend B1, a deviation from the initial target bending angle W1s occurred. Specifically, the initial actual bending angle W1i might be 92°. This can be due to various influencing factors, such as batch variations (i.e., variations in the material across different workpieces 2 processed consecutively), and / or due to prior processing of workpiece 2, which may have led to a change in the material structure of workpiece 2, and / or due to the insulating material used, and / or due to a less than optimally adjusted clamping force of the bending machine, and / or due to tolerance deviations of the initially provided workpiece 2, and / or similar factors.Depending on the length of the workpiece 2, and thus the corresponding lever arm, the deviation of the first actual bending angle W1 i from the first target bending angle W1s can ultimately have significant effects on the positions of other sections or points of the workpiece 2. For example, assuming that the second bend B2 and the third bend B3 are executed correctly, i.e., according to specifications or within tolerance, a significant deviation of the position of a distal end of the workpiece 2 from its target position can occur. As an example, a target endpoint 4 is marked here, indicating the intended position of the distal end of the workpiece 2, or the final bent section, as specified by the target geometry 3. The effect of the incorrect first bending angle W1 i is evident here in that an actual endpoint 6 resulting from the described assumption is spaced away from the target endpoint 4, i.e., does not coincide with it.It can therefore be assumed that the actual bending angle W3i achieved during the production of the third bend B3 corresponds exactly to, or will correspond to, the third target bending angle W3s. For example, the position of the actual endpoint 6 deviates from the target endpoint 4 in both the x-direction and the y-direction, for instance by several millimeters each.

[0036] As described, a correction value or correction factor can now be automatically determined for at least one of the subsequent bends to compensate for the deviation of the first actual bending angle W1i from the first target bending angle W1s. For example, a correction value of 2° was determined for the bending angle to be produced at the third bend B3, or a third correction angle W3k of 88°. Accordingly, the third bend B3 is not produced with the originally specified third target bending angle W3s of 90°, but with the correspondingly adjusted third correction angle W3k of only 88°. Furthermore, the free length of the workpiece 2 between the second bend B2 and the third bend B3 can be adjusted, in particular shortened. A corresponding shortening can therefore be determined and applied as a further correction value.

[0037] This results in a correspondingly adapted correction geometry 7. By adjusting the third bend B3, a correction endpoint 8, i.e. the distal end of the workpiece 2 or the final bent part, can then coincide with the target endpoint 4.

[0038] Overall, the correction geometry 7 may deviate from the target geometry 3 in some places. However, even with the correction geometry 7, the spatial relationship between the beginning and the distal end of the workpiece 2 or the corresponding bent part, as specified by the target geometry 3, is achieved.

[0039] Overall, the examples described show how algorithmic optimization can be implemented and applied in the bending process of workpieces, for example, insulated busbars. REFERENCE MARK LIST 1. Schedule 2 workpieces 3 Target geometry 4 Target endpoint 5 Current geometry 6 Current endpoint 7 Correction geometry 8 Correction endpoint B1 first bend B2 second bend B3 third bend W1s first target bending angle W1i first actual bending angle W3s third target bending angle W3i third actual bending angle W3k third correction angle x, y, z spatial directions S1 - S10 Procedure steps

Claims

[1] Method (1) for producing a bent part, wherein - a specified target geometry (3) for the bent part is recorded, - to achieve the desired geometry (3) by means of a bending machine, a sequence of several bending operations (B1, B2, B3) is automatically performed on a workpiece (2), - meanwhile, the actual geometry (5) of the workpiece (2) is automatically monitored and compared with the target geometry (3), - if a deviation of the actual geometry (5) from the target geometry (3) is detected, at least one correction value (W3k) is automatically determined for at least one bending operation (B3) of the sequence that has not yet been executed in order to at least partially compensate for an effect of the deviation and the sequence is adjusted accordingly, - a remaining portion (B3) of the appropriately adapted sequence of bending operations (B1, B2, B3) that has not yet been executed is carried out to produce the bent part. [2] Method (1) according to claim 1, characterized by , that the actual geometry (5) is monitored using a laser-based method. [3] Method (1) according to any of the preceding claims, characterized by , that monitoring the actual geometry (5) includes bending angle monitoring. [4] Method (1) according to any one of the preceding claims, characterized by , that monitoring the actual geometry (5) includes monitoring free lengths of workpiece (2) and / or a position, in particular a pose, of an end (6) of the workpiece (2). [5] Method (1) according to any one of the preceding claims, characterized by, that during the execution of the sequence of bending operations (B1, B2, B3) it is monitored whether the target geometry (3) including specified tolerances can still be achieved, and if this is not the case, the production of the respective bent part is automatically aborted. [6] Method (1) according to any one of the preceding claims, characterized by , that the target geometry (3) specifies an ideal form of the bent part and additionally a predetermined envelope surrounding it, which specifies a permissible tolerance, and a predetermined intervention limit, which at any point deviates from the target geometry (3) by at most as much as the envelope, in particular by less than the envelope, is recorded, wherein in the event of a detected deviation of the actual geometry (5) from the target geometry (3) the correction value (W3k) is determined only if the deviation is at least as large as the deviation of the intervention limit from the target geometry (3). [7] Method (1) according to claim 6, characterized by , that the production of the bent part is automatically aborted if, after complete completion of a bending operation (B1; B2), the actual geometry (5) lies outside the envelope at least at one point before the next bend (B2; B3) of the workpiece (2) to be produced. [8] Method (1) according to any one of the preceding claims, characterized by , that if a deviation is detected, before the execution of the next bending operation (B1, B2, B3) it is determined whether the target geometry (3) including specified tolerances can still be achieved by the at least one correction value (W3k) and if this is not the case, it is determined whether this is possible by reworking the current bend (B1, B2) and if this is the case, the reworking is carried out and the actual geometry (5) achieved is compared again with the target geometry (3). [9] Method (1) according to any one of the preceding claims, characterized by , that when the bent part is used to manufacture a conductor rail, especially for a motor vehicle. [10] Manufacturing plant for producing bent parts, comprising a bending machine for bending workpieces (2), a monitoring device for monitoring the actual geometry (5) of each workpiece (2) being processed during the production of the respective bent part, and a control unit coupled to the monitoring device for comparing the actual geometry (5) with a target geometry (3) specified for the respective bent part and for determining correction values ​​(W3k) as required for subsequent bending operations of the workpiece (2) and for controlling the bending machine accordingly, wherein the manufacturing plant is set up to carry out the method (1) according to one of the preceding claims.

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