FORMING OR SEPARATING DEVICE, AND METHOD FOR OPERATING SAME

Abstract

A forming and/or separating device 10 as well as a method for operating the same and particularly a method for checking of an undisturbed operation of the forming and/or separating device 10. The forming and/or separating device 10 is configured to process an initial workpiece 12 in a working area 19 between two tool parts 14, 15 in a chipless forming manner. An image-capturing sensor 20 captures the working area 19 and can capture at least one captured image B during the operation of the forming and/or separating device 10. An evaluation unit 24 compares the at least one captured image B with at least one reference image R or a reference model, if the forming and/or separating device 10 is in a defined operating condition. Based on the comparison it is checked whether a disturbance exists.

Claims

1. Forming and/or separating device (10) comprising: a first tool part (14) and a second tool part (15), a drive (17) that is configured to move the two tool parts (14, 15) relative to one another in order to process an initial workpiece (12) arranged in a working area (19) between the two tool parts (14, 15), in order to obtain a processed workpiece (13), at least one image-capturing sensor (20) for capturing at least one image (B), an evaluation unit (24) that is communicatively connected with the at least one image-capturing sensor (20), wherein the evaluation unit (24) is configured to determine during the operation of the forming and/or separating device (10) whether a defined operating condition of the forming and/or separating device (10) has been reached and to compare the at least one image (B) captured in this defined operating condition by the at least one image-capturing sensor (20) with an assigned stored reference image (R) and/or reference model and to check based on the comparison whether a disturbance exists.

2. Forming and/or separating device according to claim 1, characterized in that each image-capturing sensor (20) is realized by a camera (21).

3. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to determine two or more different disturbances by means of the comparison of the at least one captured image (B) with the stored reference image (R) and/or reference model.

4. Forming and/or separating device according to claim 1, characterized in that the forming and/or separating device (10) is a cyclically operating press (11), wherein each cycle comprises a phase during which the initial workpiece (12) is supplied, a phase during which the initial workpiece (12) is processed and a phase during which the processed workpiece (13) is removed, wherein two or more phases can overlap chronologically.

5. Forming and/or separating device according to claim 1, characterized in that the drive (17) is configured to move the two tool parts (14, 15) in a stroke direction (H) toward and away from each other.

6. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to determine the readiness condition for the supply of an initial workpiece (12) in the forming and/or separating device (10) as a defined operating condition of the forming and/or separating device (10).

7. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to determine the readiness condition for the forming of the initial workpiece (12) into a processed workpiece (13) as a defined operating condition of the forming and/or separating device (10).

8. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to determine the readiness condition for the removal of the processed workpiece (13) out of the forming and/or separating device (10) as a defined operating condition of the forming and/or separating device (10).

9. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to calculate an indicator value (I) during comparison of the at least one captured image (B) with the at least one reference image (R) and/or the reference model that characterizes a deviation between the at least one captured image (B) and the at least one reference image (R) and/or reference model and to compare this indicator value with a threshold (W).

10. Forming and/or separating device according to claim 9, characterized in that the evaluation unit (24) is configured to determine a disturbance if the indicator value exceeds the threshold (W).

11. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to select one image area or multiple image areas in the at least one captured image (B) and to use this image area or these image areas for the comparison with the reference image (R) and/or reference model.

12. Forming and/or separating device according to claim 11, characterized in that the evaluation unit (24) is configured to calculate a separate indicator value (I) for each image area and to compare it with the threshold (W) or one threshold (W) in each case.

13. Forming and/or separating device according to claim 1, characterized in that an illumination unit (25) is present that is configured for illuminating the area to be captured by the at least one image (B).

14. Forming and/or separating device according to claim 1, characterized in that the evaluation unit (24) is configured to carry out the capturing of the at least one image (B), the evaluation of the at least one image (B) as well as the creation of an indication to a control unit (18) of the forming and/or separating device (10) and/or a user, whether a disturbance exists, within a predefined maximum duration.

15. Forming and/or separating device according to claim 14, characterized in that the maximum duration is the duration that is the most available in order to stop the forming and/or separating device (10) before endangering a person and/or a damage of the forming and/or separating device and/or a tool of the forming and/or separating device and/or a workpiece and/or a transfer device occurs.

16. Method for operating a forming and/or separating device (10) as claimed in claim 1 that is configured to process the initial workpiece (12) arranged in the working area (19) between the first tool part (14) and the second tool part (15) in order to obtain the processed workpiece (13) and that comprises the at least one image-capturing sensor (20) and the evaluation unit (24), wherein the method comprises the following steps: Determining during the operation of the forming and/or separating device (10) whether at least one defined operating condition of the forming and/or separating device (10) has been reached, Capturing at least one image (B) by means of the at least one image-capturing sensor (20), Submitting the at least one captured image (B) to the evaluation unit (24), Comparing the at least one image (B) captured in this defined operating condition by the image-capturing sensor (20) with a reference image (R) assigned to this defined operating condition and/or a reference model assigned to this defined operating condition and determining based on the comparison whether a disturbance exists.

17. Forming and/or separating device according to claim 9, characterized in that the evaluation unit (24) is configured to select one image area or multiple image areas in the at least one captured image (B) and to use this image area or these image areas for the comparison with the reference image (R) and/or reference model.

18. Forming and/or separating device according to claim 17, characterized in that the evaluation unit (24) is configured to calculate a separate indicator value (I) for each image area and to compare it with the threshold (W) or one threshold (W) in each case.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Advantageous embodiments of the invention can be derived from the claims, the description and the drawings. In the following, preferred embodiments of the invention are explained in detail based on the attached drawings. The drawings show:

[0067] FIG. 1 a schematic block-diagram-like illustration of an embodiment of a forming and/or separating device,

[0068] FIG. 2 a flow diagram of an embodiment of a method for operating the forming and/or separating device,

[0069] FIGS. 3 to 7 a schematic illustration of disturbances in the working area in each case that can be determined by means of the invention and

[0070] FIG. 8 a schematic illustration of an image subdivided into multiple image areas as well as a reference image subdivided into multiple corresponding reference image areas, whereby individual image areas are separately compared with the respectively assigned reference image area.

DETAILED DESCRIPTION OF THE INVENTION

[0071] In FIG. 1 a forming and/or separating device 10 is highly schematically illustrated that is configured as press 11. The press 11 is configured to form an initial workpiece 12, e.g. a sheet blank, into a processed workpiece 13. The forming process is carried out in a cyclic manner according to the example. During each press cycle an initial workpiece 12 is supplied to the press 11 during a first phase, subsequently processed during a second phase by means of a chipless forming method such that the processed workpiece 13 is created and is finally removed from the press 11 in a third phase. The forming and/or separating device 10 configured as press 11 has a first tool part 14 and a second tool part 15. The first tool part 14 is arranged on a press ram 16 that is movably arranged in a stroke direction H and thus defines an upper tool so-to-speak. The second tool part 15 is arranged on a press table and is immovable according to the example. As an alternative to this, the second tool part 15 could also be arranged on a die cushion and could be moved for forming in stroke direction H by means of a die cushion drive.

[0072] Due to a relative movement between the tool parts 14, 15, they can act and process, e.g. form, the workpiece 13 to be processed from opposite sides.

[0073] For moving the press ram 16 with the first tool part 14 in stroke direction H, the press 11 comprises a drive 17. The drive 17 is controllable by means of a control device 18. The control device 18 can create a drive control signal A for drive 17, for example.

[0074] The initial workpiece 12 is supplied into a working area 19 between the first tool 14 and the second tool 15 is processed there and the created processed workpiece 13 is subsequently removed from the working area 19. Devices for supplying and for removing the workpieces 12, 13 are known per se and can be realized by gripping devices, for example. Likewise the supply and the removal of the workpieces can be carried out, for example in progressive tools in that the workpieces are connected with each other and the entire sheet strip with all workpieces is fed. The devices for supply and removal of the workpieces 12, 13 are not illustrated.

[0075] The forming and/or separating device realized by press 11 has in addition at least one image-capturing sensor 20 that is realized by a camera respectively according to the example. The camera 21 is configured to record the working area 19 and particularly the first tool part 14 and the second tool part 15 at least partly at its sections facing one another. The camera 21 is configured to capture at least one captured image B. The camera 21 is communicatively connected with an evaluation unit 24 such that the at least one captured image B can be submitted to the evaluation unit 24.

[0076] According to the example, the evaluation unit 24 is part of the control device 18. As an alternative to this, the evaluation unit 24 can also be realized separately.

[0077] As an option, an illumination unit 25 can be present for illuminating the working area 19 that can emit light in one single predefined wavelength range or in an adjustable variable wavelength range or in one of multiple different selectable wavelength ranges, for example white light and/or blue light and/or infrared light. The illumination unit 25 can be configured to illuminate the working area 19 at least during the recording of the at least one image B or permanently.

[0078] As it is illustrated in FIG. 1 by way of example, press 11 can comprise additional sensors, e.g. a position sensor 22 that creates a first sensor signal S1 as well as a drive sensor 23 that creates a second sensor signal S2 characterizing the drive condition of the drive 17. The second sensor signal S2 can characterize the rotation position or the rotation movement of a motor or a shaft of drive 17, for example. The first sensor signal S1 characterizes a ram position in stroke direction H in the embodiment.

[0079] The control device 18 controls the operation of the forming and/or separating device 10 or press 11. The position sensor 22 and the drive sensor 23 are communicatively connected with control device 18 and as an option also with evaluation unit 24 such that the sensor signals S1, S2 can be submitted to the control device 18 or also to the evaluation unit 24. It is understood that alternatively also other or in addition additional sensors can be present. Additionally or alternatively, sensors, particularly image-capturing sensors and cameras, can be directly connected to the evaluation unit 24.

[0080] The evaluation unit 24 does not have to be part of the control device 18, but can also be realized individually and can be communicatively connected with the control device 18, for example.

[0081] The evaluation unit 24 can use at least one condition signal for the determination of a defined operating condition and/or during evaluation of images. Signals can be used as condition signals that characterize the actual condition or the desired condition of the forming and/or separating device 10. For example, the sensor signals S1, S2, the control signal A and/or at least one other sensor signal, control signal or desired value can be used as condition signal.

[0082] The evaluation unit 24 is configured to check during the operation of the forming and/or separating device 10 whether a disturbance exists. The evaluation unit 24 can determine one disturbance according to the example or also multiple different disturbances, e.g. two or more of the following disturbances: [0083] An erroneous put-down position of the initial workpiece 12 or an erroneous take-up position of the processed workpiece 13 between the two tool parts 14, 15; [0084] The presence of more initial workpieces 12 between the two tool parts 14, 15 than allowed; [0085] Errors during transfer of the initial workpiece 12 or the processed workpiece 13 into or out of the working area (blocking, collision, a workpiece falling off a gripper, etc.); [0086] Incorrect orientation and/or position of the initial workpiece 12 (e.g. positioning and/or orientation errors); [0087] Incorrect initial position of the tool parts 14, 15 prior to insertion of an initial workpiece (e.g. erroneously positioned centering elements, ejection elements, movable tool components, . . . ); [0088] Missing initial workpiece 12 in a readiness condition for forming the supplied initial workpiece 12; [0089] Deformed or incorrect components of the transfer device for transfer of workpieces, such as non-opened grippers, bent arms or blades, damaged suckers etc.; [0090] Incorrect gripped or held workpieces during transfer movement; [0091] A processed workpiece 13 is present in a readiness condition for supplying of an initial workpiece 12; [0092] Erroneously processed workpiece that, for example, has not been completely formed or contains cracks or has been pulled in in a tilted manner or has been irregularly formed; [0093] Incorrectly established line connections, such as media hoses or electrical cables; [0094] Inconsistency between the present tool parts 14, 15 and a control data set in the control device 18; [0095] Wrong installation position of at least of one of the tool parts 14, 15 (e.g. wrong installation position or orientation); [0096] Presence of one or multiple non-attached or spontaneously released components of the tool parts 14, 15 in undefined position; [0097] Incorrect workpiece transfer by means of a transfer device, particularly incorrect belt feed in progressive tools, e.g. if the sheet strap got caught within the tool; [0098] Two present initial workpieces, e.g. two sheet plates, if two initial workpieces have been collectively taken and supplied by a transfer device (e.g. blank feeder); [0099] Incorrect lifting of the strap by means of the strap lifter, e.g. in progressive tools; [0100] Presence of a foreign body in the working area, for example: [0101] An element ripped down violently from a tool part 14, 15; [0102] A fluid pool on at least one tool part 14, 15, e.g. due to a leakage; [0103] A separated waste part after a separation method that was not correctly discharged or that entered into the working area 19 from an adjacent forming and/or separating device; [0104] A foreign body left behind by a person (e.g. manual tool, glove, . . . ).

[0105] An exemplary method progress in the context of this operation is illustrated in FIG. 2 in the form of a flow diagram and serves to determine or to check whether a disturbance is present or whether the operation runs in an undisturbed manner.

[0106] First, in a first method step V1 it is checked whether the forming and/or separating device 10 or press 11 is in a defined operating condition. The number of defined operating conditions can vary. In the embodiment three defined operating conditions are preset in the control device 18 or evaluation unit 24: A readiness condition for supplying an initial workpiece 12, a readiness condition for processing and according to the example forming the supplied initial workpiece 12, as well as a readiness condition for removal of the processed workpiece 13 after completion of the processing or forming process. The determination of the defined operating conditions can be carried out by evaluation of one or more signals of the control device 18 and/or by evaluation of one or more sensor signals. The first sensor signal S1 of the position sensor 22 or the second sensor signal S2 of the drive sensor 23 or further sensors can be used as sensor signals.

[0107] If in the first method step V1 is determined that a defined operating condition is actually not present (branch n from the first method step V1), the check in the first method step V1 is continued until it is determined that one of the defined operating conditions has been reached (branch p from the first method step V1). Then the method is continued in the second method step V2.

[0108] In the second method step V2 at least one captured image B of camera 21 is selected that can be assigned to the defined operating condition, e.g. the readiness condition for supplying an initial workpiece 12 or the readiness condition for forming the initial workpiece 12 or the readiness condition for removal of the processed workpiece 13.

[0109] In a third method step V3 at least one reference image R is selected from a memory or a data base that is assigned to the actually defined operating condition. The at least one captured image B and the at least one reference image R are compared with one another and it is checked based on the comparison whether a disturbance of the operation of the forming and/or separating device 10 or press 11 exists. For example, foreign bodies erroneously positioned workpieces, workpieces that comprise errors like cracks, for example, missing line connections, leakages, damages on a tool part 14, 15 or the like can be identified due to the comparison. For this the at least one captured image B and the at least one reference image R can be compared in their entirety. Alternatively, it is also possible to only select one or multiple image areas in the at least one captured image B and in the at least one reference image R and to compare the image areas with each other that correspond to one another in a captured image B and a reference image R. For example, such image areas can be compared with each other in which parts of the tool parts 14, 15 can be recognized. Background information in the image can be ignored.

[0110] In the third method step V3 an indicator value I is calculated based on the comparison that characterizes the deviation between the at least one captured image B and the at least one reference image R. Thereby it is possible to calculate one single indicator value I as comparison result or to determine one indicator value I for each comparison of two image areas in a captured image B and a corresponding reference image R respectively.

[0111] The greater and/or the more relevant the deviation between the at least one captured image B and the at least one reference image R, the greater is the calculated indicator value I.

[0112] In a fourth method step V4 it is checked whether the indicator value I exceeds a predefined threshold W. If this is the case (branch p from the fourth method step V4), the method is continued in a fifth method step V5. Otherwise (branch n from the fourth method step V4), the method starts again with the first method step V1. If multiple indicator values I have been calculated, each indicator value I can be compared with an assigned threshold W. If the indicator value I characterizes the coincidence between the at least one captured image B and the at least one reference image R instead of the deviation, then it is checked in the fourth method step V4 whether the indicator value I is below a predefined threshold W.

[0113] In a preferred embodiment of the method the captured image B is subdivided in a multiplicity of image areas B.sub.1 to B.sub.n. The directly adjacent image areas B.sub.1 to B.sub.n are preferably arranged in an overlapping manner, as schematically illustrated in FIG. 8. Depending on which defined operating condition has been determined, also in one image B only one specific image section can be checked and divided into multiple image areas B.sub.1 to B.sub.n, as schematically illustrated in FIG. 8. Each image area B.sub.1 to B.sub.n is compared with an assigned reference image R.sub.1 to R.sub.n and thereby one indicator value I.sub.1 to I.sub.n is calculated in each case (third method step V3). Subsequently, in the fourth method step V4 the largest indicator value I.sub.max can be determined first that characterizes the image area B.sub.i, where (i=1, 2, 3, . . . n), having the greatest deviation compared with the assigned reference image R.sub.i, where (i=1, 2, 3, . . . n). If this maximum indicator value I.sub.max is not greater than the threshold W (branch n from the fourth method step V4), no disturbance exists. Otherwise disturbance has been determined (branch p from the fourth method step V4) and the method is continued in the fifth method step V5. If the indicator value characterizes the coincidence between the at least one captured image B and the at least one reference image R instead of the deviation, then a minimum indicator value is used instead of the maximum indicator value.

[0114] The disturbance can be located during the comparison of individual image areas. In addition, the sensitivity with regard to deviations is the greater, the more image areas and the smaller the image areas are into which the image B is divided and/or the more the image areas overlap.

[0115] In the preferred embodiment the image areas B.sub.1 to B.sub.n overlap in order to be able to better identify deviations or disturbances that are exactly located at the position at which two image areas B.sub.1 to B.sub.n transition into one another. If an image B would only be subdivided into image areas that contact one another without overlapping, deviations at the edge of an image area and in the transition to the adjacent image area would be much more difficult to determine.

[0116] Progressing modifications in the environmental area that the camera captures, for example due to an increasing contamination of the tool, a changing illumination situation, etc. influence the at least one indicator value I in the captured image B or at least in an image area B.sub.1 thereof. Such modifications are, however, usually slow (e.g. increasing contamination of a tool) compared with the recording speed of subsequent images B or can influence all pixels or image areas of the image concurrently (sudden switching on or switching off of an illumination). These effects can be determined and can be considered during a threshold comparison. If for example the same environmental area is represented by multiple images B, an indicator value for the at least one image area B.sub.i or for the entire image B changing from image to image, i.e. increasing or decreasing, can be determined. In such a situation it can be advantageous to adapt, i.e. to increase or decrease, the threshold, e.g. in the same degree in which the indicator value changes. Moreover, a multiplicity of calculations can be executed based on the at least one indicator value I, such as analysis of the discrete mathematical deviation of the at least one indicator value I for the at least one image B over the recording points of time.

[0117] An indication is created in the fifth method step V5 that indicates that a disturbance has been determined. The indication can be output in any arbitrary manner, e.g. optically or acoustically. It can be output directly on the control device of the forming and/or separating device 10 or press 11 or remote therefrom in a control center. In the fifth method step V5 the further operation of the forming and/or separating device 10 or press 11 can be stopped in addition or as an alternative to outputting the indication, such that the disturbance can be eliminated before the operation is resumed and particularly before a damage on the forming tool or the forming device or the transport or transfer device or the workpiece occurs. After elimination of the disturbance and resumption of operation, the method starts again with the first method step V1.

[0118] In the exemplary method illustrated in FIG. 2 at least one captured image B is compared with at least one reference image R. Thereby image processing algorithms are used in order to recognize image components such as edges and/or surfaces. Based on the comparison of the at least one captured image B with the at least one reference image R or corresponding image areas, it can be concluded whether the actual operating condition represented by the at least one captured image B is coincident with the undisturbed operating condition that is characterized by the at least one reference image R. The larger or the more relevant the identified deviations, the greater is the calculated at least one indicator value I.

[0119] Alternatively or additionally to this approach and to the use of the at least one reference image R, also a reference model can be used for the comparison with the at least one captured image B. The reference model can be created by means of machine learning, for example. For this, exemplary data or other information can be input that characterize the undisturbed operation or the presence of a disturbance, for example. By means of machine learning a reference model can be created therefrom. The at least one captured image B can be evaluated and compared with the reference model such that an undisturbed or disturbed operation can then be concluded.

[0120] In FIGS. 3 to 7 different situations are schematically illustrated that can be recognized according to the invention and can be identified as disturbance. In the situation illustrated in FIG. 3, a foreign body 30 is present in the working area 19 between the tool parts 14, 15. The foreign body 30 can be an attachment means, a tool, fragments of a centering pin of a tool part 14, 15 or the like.

[0121] In the situation illustrated in FIG. 4, unintentionally two initial workpieces 12 have been placed on the second tool 15. Also this condition is determined as disturbance.

[0122] A connection area 31 for multiple lines 32 is schematically illustrated in FIG. 5. For example, the connection area 31 can be part of a tool part 14, 15 or the forming and/or separating device 10 and can be located in the image capture area of camera 21. The lines 32 can be fluidic lines and/or electrical lines. In FIG. 5 it is schematically illustrated that a connector in the connection area 31 is not connected with a respective line 32. The missing line 32 can be recognized and evaluated as being a disturbance.

[0123] In the schematic illustration in FIG. 6 the second tool part 15 is illustrated in a top view. A fluid pool 33 is schematically apparent on the second tool part 15. Such a fluid pool 33 can be created due to a leakage. Also this situation can be evaluated as disturbance.

[0124] By way of example, another disturbance case is illustrated in FIG. 7. Here, for example, the second tool part 15 is damaged at a location 34. An edge of the second tool part 15 has been chipped at this location 34. Also such a damage can be recognized as disturbance.

[0125] The examples explained based on FIGS. 3 to 7 are not conclusive. Also further situations can be recognized as disturbance. For example, a disturbance can also be present, if in the readiness condition for the insertion of an initial workpiece 12 the processed workpiece 13 from the previous cycle is still present in the working area 19.

[0126] The disturbances that can be identified can be related with the supply of the initial workpiece 12, the removal of the processed workpiece 13, the condition of the tool parts 14, 15, the mechanical or fluidic coupling thereof with the forming and/or separating device 10 as well as the electrical, fluidic or mechanical connections of the forming and/or separating device 10 themselves. Reaching a defined operating condition of the forming and/or separating device 10 is used as trigger event in order to carry out a check on a disturbance. In the preferred embodiment the start of one of the three phases during a press cycle is preset as defined operating condition respectively. Alternatively, also more or less operating conditions can be defined.

[0127] The invention refers to a forming and/or separating device 10 as well as a method for operating the same and particularly a method for checking of an undisturbed operation of the forming and/or separating device 10. The forming and/or separating device 10 is configured to process an initial workpiece 12 in a working area 19 between two tool parts 14, 15 in a chipless forming manner. An image-capturing sensor 20 captures the working area 19 and can capture at least one captured image B during the operation of the forming and/or separating device 10. An evaluation unit 24 compares the at least one captured image B with at least one reference image R or a reference model, if the forming and/or separating device 10 is in a defined operating condition. Based on the comparison it is checked whether a disturbance exists.

LIST OF REFERENCE SIGNS

[0128] 10 forming and/or separating device [0129] 11 press [0130] 12 initial workpiece [0131] 13 processed workpiece [0132] 14 first tool part [0133] 15 second first tool part [0134] 16 press ram [0135] 17 drive [0136] 18 control device [0137] 19 working area [0138] 20 image-capturing sensor [0139] 21 camera [0140] 22 position sensor [0141] 23 drive sensor [0142] 24 evaluation unit [0143] 25 illumination unit [0144] 30 foreign body [0145] 31 connection area [0146] 32 line [0147] 33 fluid pool [0148] 34 location at the second tool part [0149] A drive control signal [0150] B captured image [0151] B.sub.i image area (i=1 to n) [0152] H stroke direction [0153] R reference image [0154] R.sub.i reference image area (i=1 to n) [0155] S1 first sensor signal [0156] S2 second sensor signal [0157] V1 first method step [0158] V2 second method step [0159] V3 third method step [0160] V4 fourth method step [0161] V5 fifth method step