Bending apparatus, bending method, and computer program

Abstract

To mold a variety of tailored blank materials to a target bending angle with fewer processing times using a single processing device.SOLUTION: A bending device includes: a bending part for bending a tailored blank material in which plate materials having different bending strengths are joined to a predetermined direction; and a bend returning part for bending and returning the tailored blank material that is bent by the bending part in an opposite direction to the predetermined direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a bending apparatus, a bending method, and a computer program. [Background technology]

[0002] Forming devices that bend steel plates to a predetermined angle are known (see, for example, Patent Documents 1 and 2). In the bending method described in Patent Document 1, when bending a long workpiece, an angle sensor measures the bending angle of the workpiece. The amount of springback is corrected according to the measurement result of the angle sensor, and the workpiece is bent. As a result, the correction amount of the push-in amount is calculated from the amount of springback.

[0003] The bending device described in Patent Document 2 performs correction shaping on the bent part using the difference between the estimated value of the bent part after bending and the target value of the bending angle of the bent part. The bending described in Non-Patent Document 1 tilts the upper mold that performs bending, thereby forming the part at the target bending angle in one bending operation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-180339 A [Patent Document 2] JP 2020-099935 A [Non-patent literature]

[0005] [Non-Patent Document 1] Masaaki Otsu, "High-precision V-bending of tailored blanks", Amada Foundation, Research Grant Report, 2016, Vol. 29 Summary of the Invention [Problem to be solved by the invention]

[0006] Tailored blank materials, which are sheet materials in which steel plates of different strengths and thicknesses are butt-jointed, are known as objects to be bent. The processing methods of Patent Documents 1 and 2 cannot form tailored blank materials to a target bending angle. In addition, the processing method of Non-Patent Document 1 requires an upper die that is inclined according to the shape and material of the formed member. Therefore, the processing method of Non-Patent Document 1 requires a dedicated die for one tailored blank material, and therefore cannot process a variety of tailored blank materials.

[0007] The present invention has been made to solve the above-mentioned problems, and has an object to form a variety of tailored blank materials to a target bend angle with a small number of processing steps using a single processing device. [Means for solving the problem]

[0008] The present invention has been made to solve the above-mentioned problems, and can be realized in the following forms. A bending apparatus comprising: a bending forming unit that bends a tailored blank material, in which plate materials having different bending strengths are joined, in a predetermined direction; a bend-back forming unit that bends the tailored blank material bent by the bend forming unit in a direction opposite to the predetermined direction; and a condition calculation unit that calculates a bend angle greater than a target bend value and a bend-back angle smaller than the target bend value according to a bend target value after forming of the tailored blank material, wherein when the tailored blank material is formed by joining a first member and a second member, the condition calculation unit calculates the bend angle and the bend-back angle with respect to the first member. a bending apparatus which creates a prediction model for predicting a forming angle, which is the angle of the tailored blank material after forming, using a first angle, which is the angle of the first member after forming, determined by an angle between the first member and the bending angle relative to the second member, and a second angle, which is the angle of the second member after forming, determined by the bending angle and the bend-back angle relative to the second member, and the bending forming unit bends the tailored blank material to obtain the bend angle calculated by the condition calculation unit, and the bend-back forming unit bends back the tailored blank material bent by the bending forming unit to obtain the bend-back angle calculated by the condition calculation unit.

[0009] (1) According to one aspect of the present invention, there is provided a bending apparatus comprising a bending unit that bends a tailored blank material, in which plate materials having different bending strengths are joined, in a predetermined direction, and a bending-back unit that bends the tailored blank material bent by the bending unit back in a direction opposite to the predetermined direction.

[0010] According to this configuration, a tailored blank material in which plate materials having different bending strengths are joined is After being bent by the forming section, the blank is bent back by the bending back forming section. When bending a tailored blank material, it is necessary to bend the plate material with low bending strength more than the target bending angle in accordance with the plate material with high bending strength. In particular, in the case of a metal plate material, springback occurs, so the plate material cannot be shaped to the target bending angle unless it is bent more than the target bending angle. According to this configuration, since there is a bending back forming section that bends back the tailored blank material after it is bent by the bending forming section, it can be shaped to the target bending angle with a small number of processing operations. In addition, no special mold or the like is required according to the material of the tailored blank material. Therefore, a variety of tailored blank materials can be processed by using the same forming device, simply by changing the forming conditions for the bending angle by the bending forming section and the bending back angle by the bending back forming section.

[0011] (2) The bending forming apparatus of the above aspect may further include a condition calculation unit that calculates a bend angle greater than a target bend value and a bend-back angle smaller than the target bend value in accordance with a target bend value after forming of the tailored blank material, and after the bend forming unit bends the tailored blank material to obtain the calculated bend angle, the bend-back forming unit may bend back the tailored blank material to obtain the calculated bend-back angle. According to this configuration, the bending section forms the tailored blank material at a bending angle greater than the target bending value. When a tailored blank material made of metal is bent, springback occurs. In contrast, the bending device of this configuration bends a plate material with low bending strength that has been bent excessively beyond the target bending value back to the target bending value, so that the tailored blank material can be formed to the target bending value with fewer processing operations.

[0012] (3) In the bending forming apparatus of the above aspect, when the tailored blank material is formed by joining a first member and a second member, the condition calculation unit may create a prediction model to predict a forming angle, which is the angle of the tailored blank material after forming, using a first angle, which is the angle of the first member after forming, determined by the bending angle and the bend-back angle with respect to the first member, and a second angle, which is the angle of the second member after forming, determined by the bending angle and the bend-back angle with respect to the second member. According to this configuration, a prediction model is created using a first angle and a second angle after forming, which are determined by the bending angle and the bending back angle, for each of the first and second members used as a tailored blank material. There are multiple combinations of bending angles and bending back angles for forming the bend to the target value. In contrast, by determining a common solution that satisfies the bending target value where the first angle and the second angle are the same from combinations that form the first angle and the second angle, the tailored blank material can be formed to the bending target value with fewer processing operations.

[0013] (4) In the bending forming apparatus of the above aspect, a correction unit may be further provided that corrects the prediction model using a predicted value of the forming angle obtained using the prediction model and a measured value of the forming angle. According to this configuration, the prediction model is corrected using the predicted values ​​of the prediction model and the measured values ​​of the actually formed tailored blank material, thereby improving the prediction accuracy of the prediction model. By using a prediction model with improved accuracy, the tailored blank material can be formed to the target bending value with fewer processing operations.

[0014] (5) In the bending forming apparatus of the above aspect, the bending angle acquisition unit may further acquire the first angle and the second angle, and the correction unit may correct the prediction model using the first angle and the second angle acquired by the bending angle acquisition unit. According to this configuration, the prediction model is corrected using the first angle and the second angle acquired for the first member and the second member, respectively, so that the accuracy of the prediction model can be further improved.

[0015] (6) The bending forming apparatus of the above aspect may further include a conveying unit that conveys the tailored blank sheet in a feed direction, and the tailored blank sheet is joined along the feed direction in the order of the first member, the second member, and the third member, so that the tailored blank sheet is formed in the order of the first member, the second member, and the third member, and when an angle of the third member after forming, determined by the bending angle and the bend-back angle for the third member, is defined as a third angle, the bending forming unit and the bend-back forming unit may form the first member at the bending angle and the bend-back angle using the predictive model created using the first angle and the second angle, form the third member at the bending angle and the bend-back angle using the predictive model created using the second angle and the third angle, and gradually change the second member from the bending angle and the bend-back angle at the time of forming the first member to the bending angle and the bend-back angle at the time of forming the third member, using the second angle, as the feed amount by the conveying unit increases. According to this configuration, the tailored blank material in which three members are joined along the conveying direction is processed by the bending section and the bending back section while being conveyed by the conveying section. The first member is formed by the bending angle and bending back angle of a common solution predicted from the first angle and the second angle. The third member is formed by the bending angle and bending back angle of a common solution predicted from the second angle and the third angle. The forming angle when the second member sandwiched between the first member and the third member is bent and bent back changes as the feed amount increases so as to connect from the common solution when forming the first member to the common solution when forming the third member. In addition, the second angle when processing the second member to the bending target value is used for this change. Therefore, according to this configuration, while forming the first member and the third member to the bending target value, the second member connecting the first member and the third member can also be formed to the bending target value. Furthermore, the shaping change from the first member to the second member and the shaping change from the second member to the third member can be smoothly connected.

[0016] The present invention can be realized in various forms, for example, in the form of a bending forming apparatus, a processing apparatus, a manufacturing apparatus, and apparatus and systems including these, as well as a bending forming method, a processing method, a manufacturing method, and computer programs for executing these systems and methods, a server device for distributing this computer program, and a non-transitory storage medium on which the computer program is stored. [Brief description of the drawings]

[0017] [Figure 1] 1 is a schematic block diagram of a bending apparatus according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an explanatory diagram of a plate material which is a tailored blank material. [Diagram 3] FIG. 2 is an explanatory diagram of a plate material which is a tailored blank material. [Figure 4] FIG. 2 is an explanatory diagram of a plate material which is a tailored blank material. [Diagram 5] FIG. [Figure 6] FIG. 1 is an explanatory diagram of bending back forming. [Figure 7] FIG. 10 is an explanatory diagram of a load applied to a plate material. [Figure 8] FIG. 11 is an explanatory diagram of a bending angle during bending and a bending-back angle during bending-back. [Figure 9] FIG. 11 is an explanatory diagram of a bending angle during bending and a bending-back angle during bending-back. [Figure 10] 10 is an explanatory diagram for determining the bending angle and the unbending angle of a plate material. FIG. [Figure 11] FIG. 11 is an explanatory diagram of correction of a prediction model. [Figure 12] FIG. 11 is an explanatory diagram of correction of a prediction model. [Figure 13] 4 is a flowchart of the bending method of the present embodiment. [Figure 14] FIG. 4 is an explanatory diagram of the relationship between a bending target value and a bending angle after processing. [Figure 15] FIG. 4 is an explanatory diagram of the relationship between a bending target value and a bending angle after processing. [Figure 16] FIG. 4 is an explanatory diagram of the relationship between a bending target value and a bending angle after processing. [Figure 17] FIG. 4 is an explanatory diagram of the relationship between a bending target value and a bending angle after processing. [Figure 18] FIG. 11 is an explanatory diagram of the bending angle of a plate material before and after correction of a prediction model. [Figure 19] FIG. 11 is an explanatory diagram of the bending angle of a plate material before and after correction of a prediction model. [Figure 20] FIG. 4 is an explanatory diagram of a bending apparatus according to a second embodiment. [Figure 21] FIG. 4 is an explanatory diagram of a bending apparatus according to a second embodiment. [Figure 22] FIG. 4 is an explanatory diagram of a bending apparatus according to a second embodiment. [Figure 23] FIG. 11 is a schematic perspective view of a plate material processed by the bending apparatus of the second embodiment. [Figure 24] FIG. 4 is an explanatory diagram of a state of a forming tool during bending. [Diagram 25]FIG. 4 is an explanatory diagram of a state of a forming tool during bending. [Figure 26] FIG. 4 is an explanatory diagram of a state of a forming tool during bending. [Figure 27] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Figure 28] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Figure 29] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Diagram 30] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Diagram 31] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Diagram 32] 10 is an explanatory diagram of the position of a bending tool and the position of an unbending tool relative to the feed amount of a plate material. FIG. [Diagram 33] 6 is an explanatory diagram of the bending angle and the unbending angle when bending the second member and the third member. FIG. [Diagram 34] FIG. 11 is a schematic perspective view of a bending apparatus according to a third embodiment. [Diagram 35] 4 is a schematic cross-sectional view perpendicular to the feeding direction of the second feed roller. FIG. [Diagram 36] 2 is a schematic cross-sectional view perpendicular to the feed direction of the bending tool. FIG. [Figure 37] FIG. 2 is a schematic cross-sectional view perpendicular to the feed direction of the bending back forming tool. [Figure 38] FIG. 11 is a schematic front view of a bending apparatus according to a fourth embodiment. [Figure 39] FIG. 13 is an explanatory diagram of a bending target value in the fourth embodiment. [Diagram 40] FIG. 2 is a schematic front view of the bending device during bending. [Diagram 41] FIG. 2 is a schematic front view of the bending device during unbending. [Diagram 42] 13 is a flowchart of a bending method according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] First Embodiment 1. Overview of bending equipment: Fig. 1 is a schematic block diagram of a bending apparatus 100 according to a first embodiment of the present invention. The bending apparatus 100 shown in Fig. 1 bends a plate material OB, which is a processing target, in a predetermined direction, and then bends it back in the opposite direction to the predetermined direction, thereby forming the plate material OB to a target bending angle. By using the bending apparatus 100 of this embodiment, when processing a tailored blank material in which steel plates with different strengths are joined, it is possible to process the tailored blank material to a target bending angle with a small number of processing operations.

[0019] The bending apparatus 100 of this embodiment is a V-bending apparatus that bends a plate material OB, which is a tailored blank material in which steel plates with different strengths are joined. As shown in Fig. 1, the bending apparatus 100 includes an upper die 10 and a lower die 20 that bend the plate material OB, a first camera (bending angle acquisition unit) 30 and a second camera (bending angle acquisition unit) 40 that photograph the plate material OB, and a control device 50 that controls the movements of the upper die 10 and the lower die 20.

[0020] As shown in FIG. 1, the upper mold 10 includes a central upper mold 12 located in the middle, and outer upper molds 11 and 13 arranged on either side of the central upper mold 12. Similarly, the lower mold 20 includes The bending machine includes a central lower die 22 located in the middle, and outer lower dies 21, 23 arranged on either side of the central lower die 22. Each of the upper dies 11-13 and each of the lower dies 21-23 move up and down separately along a vertical direction (Z-axis direction) DR21. Each of the upper dies 11-13 and each of the lower dies 21-23 are arranged at positions facing each other on the XY plane. The vertical movements of each of the upper dies 11-13 and each of the lower dies 21-23 are controlled by a control device 50, so that the plate material OB can be bent. Note that the Cartesian coordinate system CS formed by the X-axis, Y-axis, and Z-axis shown in FIG. 1 corresponds to the Cartesian coordinate system CS shown in FIG. 5 and subsequent figures.

[0021] Each of Figs. 2 to 4 is an explanatory diagram of a plate material OB that is a tailored blank material. Fig. 2 shows a schematic perspective view of a body frame FR of an automobile that uses a tailored blank material. Fig. 3 shows an example of a tailored blank material OB1 used as an upper frame UF of the body frame FR. As shown in Fig. 3, the tailored blank material OB1 has a hollow rectangular column shape. The tailored blank material OB1 is formed by joining a first member MA and a second member MB, which have different strengths, along a center line parallel to the longitudinal direction. Note that in Figs. 3 and 4, the first member MA and the second member MB are distinguished from each other by different hatching.

[0022] Figure 4 shows an example of a tailored blank material OB2 used as a rocker frame RF of a vehicle body frame FR. As shown in Figure 4, the tailored blank material OB2 is a member formed by bending a plate material at several locations along the longitudinal direction. The tailored blank material OB2 has a first member MA and a second member MB, which have different strengths, joined in a cross section perpendicular to the longitudinal direction. The bending apparatus 100 of this embodiment bends the tailored blank materials OB1 and OB2.

[0023] The first camera 30 and the second camera 40 shown in FIG. 1 are arranged at positions where they can photograph the bending angle of the bent plate material OB. Specifically, as shown in FIG. 1, the first camera 30 and the second camera 40 are arranged at one end side and the other end side opposite to the one end side in the longitudinal direction (Y-axis direction) of the upper mold 10 and the lower mold 20, respectively. Therefore, the first camera 30 can photograph the bending angle of the first member MA of the plate material OB. Similarly, the second camera 40 can photograph the bending angle of the second member MB of the plate material OB. The photographed images taken by the first camera 30 and the second camera 40 are transmitted to the control device 50 and used for controlling the upper mold 10 and the lower mold 20.

[0024] The control device 50 is a personal computer for acquiring images captured by the first camera 30 and the second camera 40, and controlling the upper mold 10 and the lower mold 20. As shown in Fig. 1, the control device 50 includes a CPU 51, a storage unit 56, a communication unit 57 for transmitting and receiving information to and from other devices, an output unit 58, and an input unit 59.

[0025] The input unit 59 is composed of a keyboard and a mouse. The input unit 59 transmits the input received by the input unit 59 to the CPU 51 as input information. The output unit 58 has a monitor capable of displaying various images and a speaker for outputting sound. The output unit 58 performs various outputs in accordance with the output information transmitted from the CPU 51. The memory unit 56 stores a bending target value θ , which is a target bending angle, when bending the plate material OB using the upper die 10 and the lower die 20. target A prediction model MD for calculating the load applied to the plate material OB by each of the upper die 10 and the lower die 20 is stored based on the above data. The prediction model MD will be described in detail later.

[0026] The CPU 51 executes a program stored in a read only memory (ROM) (not shown) by expanding the program in a random access memory (RAM). The CPU 51 executes a program by calculating a bending target value θ of the plate material OB. target a calculation unit (condition calculation unit) 53 that calculates the load to be applied to the plate material OB, a drive control unit 52 that controls the upper die 10 and the lower die 20 according to the load calculated by the calculation unit 53, and a correction unit 54 that corrects the prediction model MD. The calculation unit 53 calculates the load to be applied to the plate material OB by the upper die 10 and the lower die 20 using the prediction model MD stored in the memory unit 56.

[0027] FIG. 5 is an explanatory diagram of bending. As shown in FIG. 5, when bending the plate material OB, the drive control unit 52 first performs bending in a predetermined direction using the upper mold 10 and the lower mold 20. In this embodiment, the drive control unit 52 bends the plate material OB downward in the vertical directions DR11 to DR13 and DR21 to DR23 as the predetermined direction. At this time, as shown in FIG. 5, the drive control unit 52 uses the central upper mold 12 to apply a load downward in the vertical direction DR22 to the plate material OB. At the same time, the drive control unit 52 uses the outer lower molds 21 and 23 to apply a load upward in the vertical directions DR11 and DR13 to the plate material OB. The drive control unit 52 does not apply a load to the outer upper molds 11 and 13 and the central lower mold 22, so that the outer upper molds 11 and 13 and the central lower mold 22 follow the movement of the plate material OB to be bent.

[0028] FIG. 6 is an explanatory diagram of bending back. As shown in FIG. 6, the drive control unit 52 performs bending back by bending back the plate material OB in the opposite direction to the predetermined direction using the upper die 10 and the lower die 20 after bending. The drive control unit 52 bends back the plate material OB in the upward direction in the vertical directions DR11 to DR13 and DR21 to DR23, which is the opposite direction to the predetermined direction. At this time, the drive control unit 52 applies a load to the plate material OB in the upward direction in the vertical direction DR22 using the central lower die 22 as shown in FIG. 6. At the same time, the drive control unit 52 applies a load to the plate material OB in the downward direction in the vertical directions DR11 and DR13 using the outer upper dies 11 and 13 as shown in FIG. 6. The drive control unit 52 does not apply a load to the central upper die 12 and the outer lower dies 21 and 23, so that the central upper die 12 and the outer lower dies 21 and 23 follow the movement of the plate material OB to be bent. The load applied to the sheet material OB during bending and bending back is calculated by a calculation unit 53 using a prediction model MD. In this embodiment, the central upper die 12 and the outer lower dies 21 and 23 correspond to a bending forming unit. The outer upper dies 11 and 13 and the central lower die 22 correspond to a bending back forming unit.

[0029] FIG. 7 is an explanatory diagram of the load applied to the plate material OB. In FIG. 7, the bending target value θ target1 shows a schematic perspective view of a plate material OB bent to a target value θ 1 . In the plate material OB, the bending strength of the first member MA and the bending strength of the second member MB are different. In addition, since the first member MA and the second member MB are made of steel plates, springback occurs during bending. For this reason, the drive control unit 52 of this embodiment uses the upper die 10 and the lower die 20 to bend the plate material OB to a target value θ 1 . target After bending the plate material OB more than this, the plate material OB is bent back by bending back forming.

[0030] 8 and 9 show the bending angle θ f_load and the bending angle θ during bending b_load 8 and 9 are explanatory diagrams of the bending angle θ f_load The bending angle is θ b_load When bending the material, the bending angle θ of each part after forming is unload_A and the bending back angle θ unload_B The calculation unit 53 calculates a plurality of bending angles θ f_load and the bending angle θ b_load The calculation unit 53 obtains the bending result by using the obtained result. f_load and the bending angle θ b_load The bending angle θ after forming is determined by unload_A ,θ unload_B In this embodiment, the prediction model MD is a regression model. unload_A corresponds to the first angle, and the bending angle θ unload_B corresponds to the second angle.

[0031] The calculation unit 53 calculates the bending target value θ target is the bending angle θ after forming unload_A ,θ unload_B 8, the curve CBa of the first member MA is calculated from the relationship shown in Fig. 8, and the curve CBb of the second member MB is calculated from the relationship shown in Fig. 9. f_load and Bending angle θb_load 10 is an explanatory diagram of how the bending angle θ is determined. As shown in FIG. 10, the calculation unit 53 calculates an intersection point CP1 between the curve CBa of the first member MA and the curve CBb of the second member MB. The calculation unit 53 calculates the bending angle θ f_load and the bending back angle θ b_load The drive control unit 52 adopts these as forming conditions when processing the plate material OB.

[0032] 1 corrects the prediction model MD using the images captured by the first camera 30 and the second camera 40. The first camera 30 and the second camera 40 correct the bending angle θ f_load and the bending angle θ b_load The bending angle θ after forming of the plate material OB processed using unload The correction unit 54 obtains a captured image of the bending angle θ after processing, for which the captured image is calculated. unload The correction unit 54 calculates the error between the measured value and the predicted value using the prediction model MD. If the calculated error is within a preset allowable error range, the correction unit 54 ends the processing of the plate material OB. On the other hand, if the calculated error is outside the allowable range, the correction unit 54 corrects the prediction model MD so that the actual measurement value and the predicted value match.

[0033] 11 and 12 are explanatory diagrams for correcting the prediction model MD. In the present embodiment, as shown in FIG. 11, the correcting unit 54 corrects the bending angle θ unload_A Correction factor C A By multiplying by , the bending angle θ of the first member MA after forming is unload_A In the same manner, the correction unit 54 corrects the bending angle θ unload_B Correction factor C B By multiplying by , the bending angle θ of the second member MB after forming is obtained. unload_B The correction unit 54 corrects the corrected bending angle θ of the first member MA after forming. unload_A and the bending angle θ of the second member MB after forming. unload_Band corrects the prediction model MD before correction. The drive control unit 52 reshapes the shaped plate material OB using the corrected prediction model MD. The correction unit 54 corrects the prediction model MD until the actual measurement value of the reshaped plate material OB falls within the range of the allowable error of the predicted value.

[0034] 2. Bending process: 13 is a flowchart of the bending method of the present embodiment. In the bending flow shown in FIG. 13, first, the setting unit 55 sets a bending target value θ target (Step S1). The setting unit 55 sets the bending target value θ of the plate material OB based on the input information acquired via the input unit 59 or the communication unit 57. target Set.

[0035] The calculation unit 53 calculates the bending angle and the unbending angle of the plate material OB using the prediction model MD stored in the storage unit 56 (step S2). target is the bending angle θ after forming of the prediction model MD unload The bending angle θ f_load and the bending back angle θ b_load Calculate the following:

[0036] 5, the drive control unit 52 executes a bending process of bending the plate material OB by controlling the upper die 10 and the lower die 20 (step S3). f_load The drive control unit 52 controls the central upper die 12 and the outer lower dies 21, 23 so that the bending angle θ of the sheet material OB is calculated. The drive control unit 52 controls the upper die 10 and the lower die 20 to perform a bending-back forming process for bending back the sheet material OB as shown in FIG. 6 (Step S4). b_load The outer upper dies 11, 13 and the central lower die 22 are controlled so as to achieve the above.

[0037] The correction unit 54 calculates a measurement value of the bending angle of the plate material OB after forming using the images captured by the first camera 30 and the second camera 40 (step S4). The correction unit 54 calculates whether the calculated measurement value is equal to or smaller than the bending target value θtarget It is determined whether the measured value is within a preset allowable error range (step S6). If the measured value is within the error range (step S6: YES), the processing of the plate material OB is completed.

[0038] In step S6, if the measured value is outside the error range (step S6: NO), the correction unit 54 corrects the prediction model MD (step S7). As shown in Figs. 11 and 12, the correction unit 54 of the present embodiment corrects the bending angle θ unload_A and the bending angle θ of the second member MB after forming unload_B The correction coefficient C calculated based on the measured value A ,C B The calculation unit 53 corrects the prediction model MD using the corrected prediction model MD. The calculation unit 53 calculates the bending angle θ of the plate material OB to be reworked using the corrected prediction model MD. f_load and the bending angle θ b_load Then, the processes from step S3 onwards are repeated.

[0039] 3.Effects: Each of the figures from Fig. 14 to Fig. 17 shows the bending target value θ target FIG. 14 is an explanatory diagram of the relationship between the bending target value θ target The bending angle θ calculated using the prediction model MD when f_load and the bending angle θ b_load 14 shows an example of the relationship between the bending angle of the first member MA after processing calculated from the image captured by the first camera 30 and the bending angle of the second member MB after processing calculated from the image captured by the second camera 40. For example, the bending target value θ of the plate material OB target When the bending angle θ is 40 degrees, the bending angle θ calculated using the prediction model MD is f_load is 45.55 degrees, and the bending angle θ b_load The bending angle of the first member MA after forming is 40.09 degrees, and the bending angle of the second member MB is 40.14 degrees. In the examples shown in FIGS. 14 to 17, the allowable error range is target It is set to ±0.5 degrees.

[0040] In each of Figs. 15 to 17, the bending target value θ target The relationship between the X-coordinate position and the Z-coordinate position of the plate material OB after forming is shown when the bending angle is 40 degrees, 45 degrees, and 50 degrees. In each figure, the relationship of the first member MA calculated from the image captured by the first camera 30 is shown by a solid line, and the relationship of the second member MB calculated from the image captured by the second camera 40 is shown by a dashed line. Since the bending strength of the first member MA and the bending strength of the second member MB are different, in the example shown in Figures 15 to 17, the position of the first member MA after processing and the position of the second member MB do not completely match. As shown in Figure 14, when the bending target value θ target Since the bending angle of the first member MA and the bending angle of the second member when the bending angle is 50 degrees are outside the range of the allowable error, the correction unit 54 corrects the prediction model MD.

[0041] 18 and 19 are explanatory diagrams of the bending angle of the plate material OB before and after the correction of the prediction model MD. FIG. 18 shows the bending angle when a new plate material OB is processed by the corrected prediction model MD. When the prediction model MD corrected by the correction unit 54 is used, as shown in FIG. 18, the new plate material OB is processed at a bending angle θ f_load is bent at 58.01 degrees, and the return angle is θ b_load As a result, in the processed plate material OB, the bending angle of the first member MA is 50.48 degrees, and the bending angle of the second member MB is 49.96 degrees.

[0042] In Fig. 19, the bending target value θ target The relationship between the X-coordinate position and the Z-coordinate position is shown when a new plate material OB is machined using the corrected prediction model MD, with the angle being 50 degrees. In Fig. 19, similar to Fig. 17, the relationship of the first member MA is shown by a solid line, and the relationship of the second member MB is shown by a dashed line. As shown in Figs. 17 to 19, by correcting the prediction model MD, the accuracy of machining the plate material OB using the prediction model MD is improved.

[0043] As described above, in the bending apparatus 100 of this embodiment, when bending the plate material OB, the drive control unit 52 uses the upper die 10 and the lower die 20 to perform bending in a predetermined direction. After bending, the drive control unit 52 uses the upper die 10 and the lower die 20 to perform bending back the plate material OB in the direction opposite to the predetermined direction. When bending the plate material OB, the drive control unit 52 bends a plate material with a low bending strength (e.g., the second member MB) at a bending target value θ in accordance with a plate material with a high bending strength (e.g., the first member MA). target In particular, metal plate O In the case of B, springback occurs, so the bending target value θ target If the bending is not excessive, the bending target value θ target According to the bending apparatus 100 of the present embodiment, after the plate material OB is bent using the upper die 10 and the lower die 20, the plate material OB is bent back using the upper die 10 and the lower die 20. Therefore, the plate material OB can be bent to the bending target value θ with a small number of processing steps. target In addition, in this embodiment, no special upper or lower mold is required according to the material constituting the plate material OB. Therefore, the same bending apparatus 100 can be used to form the plate material OB at a bending angle θ f_load and the bending angle θ b_load By simply changing the molding conditions, a variety of sheet materials OB can be processed.

[0044] In addition, in the bending apparatus 100 of this embodiment, the drive control unit 52 uses the upper die 10 and the lower die 20 to rotate the plate material OB at a target value θ target After bending the plate material OB more than the bending target value θ , the plate material OB is bent back by bending back. When a plate material OB made of metal is bent, springback occurs. In contrast, in the bending device 100 of the present embodiment, target The plate material with low bending strength is bent more than the target bending value θ target In order to bend the plate material OB back to the target value θ with fewer processing steps, target It can be molded into.

[0045] In addition, the calculation unit 53 of the present embodiment calculates a plurality of bending angles θ f_load and the bending angle θb_load The calculation unit 53 obtains the bending result by using the obtained result. f_load and the bending angle θ b_load The bending angle θ after forming is determined by unload_A ,θ unload_B A prediction model MD is created, which is a curved surface that represents the bending target value θ target The bending angle θ for forming f_load and the bending back angle θ b_load In contrast, in this embodiment, the bending angle θ unload_A and the bending angle θ of the second member MB after forming. unload_B From the combination of these, the bending angle θ unload_A and bending angle θ unload_B The bending target value θ target In this way, the bending apparatus 100 of the present embodiment can bend the plate material OB to the target value θ with fewer processing times. target It can be molded into

[0046] Furthermore, the correction unit 54 of the present embodiment corrects the prediction model MD using the captured images of the first camera 30 and the second camera 40. The first camera 30 and the second camera 40 correct the bending angle θ calculated using the prediction model MD. f_load and the bending angle θ b_load The bending angle θ after forming of the plate material OB processed using unload The photographed image is acquired. The normal part 54 is a photographed image of the bending angle θ after processing, for which the photographed image is calculated. unload The error between the measured value and the predicted value using the prediction model MD is calculated. Since the prediction model MD is corrected using the predicted value of the prediction model MD and the measured value of the actually formed plate material OB, the prediction accuracy of the prediction model MD is improved. By using the prediction model MD with improved accuracy, the plate material OB can be bent to the target value θ with fewer processing operations. target In addition, when the first member MA and the second member MB are bent separately, the bending angle θ unload_A ,θ unload_Bis used to correct the prediction model MD. This allows the bending apparatus 100 of this embodiment to further improve the accuracy of the prediction model MD.

[0047] <Second embodiment> Each of the drawings from FIG. 20 to FIG. 22 is an explanatory diagram of a bending apparatus of the second embodiment. In the second embodiment, a forming tool 10A, which is a substitute for the upper mold 10 and the lower mold 20 of the first embodiment, forms the plate material OBa while feeding it. The plate material OBa formed in the second embodiment is a tailored blank material in which three different steel materials are joined in order. FIG. 20 shows a schematic front view of the forming tool 10A. FIG. 21 shows a schematic view of the aa cross section in FIG. 20. FIG. 22 shows a schematic view of the bb cross section in FIG. 20. Note that the configuration of the control device that controls the forming tool 10A of the second embodiment is the same as the configuration of the control device 50 of the first embodiment, so it is omitted in FIG. 20.

[0048] As shown in FIGS. 20 to 22, the forming tool 10A is used for a plate material OBa to be processed. The conveying machine includes three upper rollers (conveying sections) 10a1-10a3 arranged on the Z-axis positive side (upper side) and three lower rollers (conveying sections) 10b1-10b3 arranged on the Z-axis negative side (lower side). The upper rollers 10a1-10a3 and the lower rollers 10b1-10b3 convey the plate material OBa in a feed direction parallel to the Y-axis, while bending and unbending the plate material OBa. As shown in Figs. 21 and 22, the upper roller 10a2 of the upper rollers 10a1-10a3 and the rollers 10b1 and 10b3 of the lower rollers 10b1-10b3 are arranged upstream of the other rollers 10a1, 10a2 and 10b2 in the feed direction (negative Y-axis direction).

[0049] Each of the upper rollers 10a1 to 10a3 and the lower rollers 10b1 to 10b3 moves up and down along the Z-axis direction. As a result, the upper roller 10a2 arranged on the upstream side of the feed direction and the lower rollers 10b1 and 10b3 perform bending of the plate material OBa. On the other hand, the upper rollers 10a1 and 10a3 arranged on the downstream side of the feed direction (positive Y-axis direction) and the lower roller 10b2 perform bending back of the plate material OBa. In the following, the upper roller 10a2 and the lower rollers 10b1 and 10b3 that perform bending back are also referred to as bending tools 10a2, 10b1, and 10b3. The upper rollers 10a1 and 10a3 and the lower roller 10b2 that perform bending back are also referred to as bending back tools 10a1, 10a3, and 10b2.

[0050] 23 is a schematic perspective view of a plate material OBa processed by the bending device of the second embodiment. The bending device of the second embodiment processes the plate material OBa in a direction perpendicular to a portion where different materials are joined, as a feed direction. Specifically, the bending device processes the first member MA, the second member MB, and the third member MC in the feed order.

[0051] Each of Figs. 24 to 26 is an explanatory diagram of the state of the forming tool 10A during bending and unbending. Fig. 24 shows a schematic front view of the forming tool 10A. Fig. 25 shows a schematic view of the aa cross section in Fig. 24. Fig. 26 shows a schematic view of the bb cross section in Fig. 24. As shown in Fig. 25, the bending forming tools 10a2, 10b1, and 10b3 feed the plate material OBa in the feed direction by rotating around the X-axis. The bending forming tools 10a2, 10b1, and 10b3 further move up and down in the Z-axis direction to bend the plate material OBa at a bending angle θ f_load Mold into.

[0052] 26, the unbending forming tools 10a1, 10a3, and 10b2 rotate around the X-axis to feed the plate material OBa in the feed direction. The unbending forming tools 10a1, 10a3, and 10b2 further move up and down in the Z-axis direction to bend the plate material OBa back at an unbending angle θb_load In addition, in Fig. 26, for comparison with the bending and unbending angle, the plate material OBa bent to the bending angle by the bending tools 10a2, 10b1, and 10b3 shown in Fig. 25 is shown by a broken line.

[0053] Each of Fig. 27 to Fig. 32 is an explanatory diagram of the position PTf of the bending tools 10a2, 10b1, 10b3 and the position PTb of the unbending tools 10a1, 10a3, 10b2 with respect to the feed amount of the plate material OBa. Fig. 27, 29, 31 show the relationship between the position PTf of the bending tools 10a2, 10b1, 10b3 and the position PTb of the unbending tools 10a1, 10a3, 10b2 with respect to the plate material OBa. Fig. 28, 30, 32 show the bending angle θ of the bending tools 10a2, 10b1, 10b3 with respect to the feed amount of the plate material OBa. f_load and the bending angle θ of the bending tools 10a2, 10b1, and 10b3. b_load The trend is shown as follows.

[0054] Fig. 28 shows a state where bending of the first member MA of the plate material OB shown in Fig. 27 has started. The calculation unit 53 of the control device 50 of the second embodiment calculates the bending speed of the first member MA. Rear bending angle θ unload_A and the bending angle θ of the second member MB after forming. unload_B Using the above, the bending angle θ in the section PA f_load and the bending angle θ b_load The drive control unit 52 calculates the position PTf of the bending tools 10a2, 10b1, and 10b3 in the state shown in FIG. 28 in the range of the section PA, so that the bending angle of the plate material OBa is the bending angle θ f_load In the same manner, the drive control unit 52 sets the position PTb of the unbending tools 10a1, 10a3, and 10b2 that have not yet performed the unbending of the first member MA to a position where the unbending angle of the plate material OBa in the section PA is the unbending angle θ b_load Set it so that

[0055] Fig. 30 shows a state in which the feed rate of the plate material OBa is increased from the state shown in Fig. 28, and bending back of the first member MA of the plate material OB shown in Fig. 29 is started. In this state, as shown in Fig. 30, the positions PTf and PTb of the bending tools 10a2, 10b1, and 10b3 are the same as those shown in Fig. 28.

[0056] Fig. 32 shows a state where the feed amount of the plate material OBa is increased from the state shown in Fig. 30, and bending of the second member MB of the plate material OB shown in Fig. 31 is started. In this state, the drive control unit 52 changes the positions PTf of the bending tools 10a2, 10b1, and 10b3 in accordance with the feed amount, as shown in a section PB in Fig. 32.

[0057] FIG. 33 shows the bending angle θ f_load and the bending angle θ b_load FIG. 33 is an explanatory diagram of the bending angle θ determined by the first member MA, the second member MB, and the third member MC as in FIG. f_load and the bending angle θ b_load The intersection point CP1 is a bending angle θ calculated by the prediction model MD of the first member MA and the second member MB. f_load and the bending angle θ b_load This represents the following.

[0058] In the section PA in FIG. 32, the drive control unit 52 determines the bending angle θ f_load and the bending angle θ b_load 32, the drive control unit 52 controls the forming tool 10A so as to correspond to the bending angle θ f_load and the bending angle θ b_load Specifically, the calculation unit 53 controls the forming tool 10A so as to correspond to the bending angle θ unload_B The bending angle θ in the section PC is calculated by using the bending angle (third angle) after forming of the third member. f_loadand the bending angle θ b_load Calculate the following:

[0059] On the other hand, in the section PB where the forming of the second member MB starts, the drive control unit 52 drives the curve C from the intersection point CP1 to the intersection point CP2 along the curve CBb of the second member MB from the start of forming the second member to the completion of forming. PB Specifically, the calculation unit 53 controls the bending angle θ of the first member MA so as to gradually change along the line as the feed amount of the plate material OBa increases. f_load (or the bending angle θ b_load ) from the bending angle θ of the third member MC f_load (or the bending angle θ b_load ) gradually increase the bending angle θ f_load (or the bending angle θ b_load In the section PB, the drive control unit 52 changes the bending angle θ unload_B The curve C where PB Along the bending angle θ f_load (or the bending angle θ b_load As a result, in the section PB of FIG. 32, the positions PTf of the bending tools 10a2, 10b1, and 10b3 and the positions PTb of the unbending tools 10a1, 10a3, and 10b2 are changed according to a gradually changing bending angle θ f_load and the bending angle θ b_load The amount of feed varies depending on the feed rate.

[0060] As described above, the drive control unit 52 of the second embodiment controls the bending angle θ unload_A and the bending angle θ of the second member MB after forming. unload_B The bending angle θ in the section PA calculated using f_load and the bending angle θ b_load This allows bending and unbending The drive control unit 52 controls the bending angle θ of the second member MB after forming. unload_B The bending angle θ in the section PC calculated using the bending angle (third angle) after forming of the third member f_load and the bending angle θ b_loadAs the feed rate of the plate material OBa increases, the drive control unit 52 controls the bending angle θ f_load (or the bending angle θ b_load ) from the bending angle θ of the third member MC f_load (or the bending angle θ b_load ) gradually increase the bending angle θ f_load (or the bending angle θ b_load In the section PB, the drive control unit 52 changes the bending angle θ unload_B The curve C where PB Along the bending angle θ f_load (or the bending angle θ b_load ) is changed. Therefore, the bending angle and unbending angle when forming the second member MB sandwiched between the first member MA and the third member MC change as the feed amount increases so as to connect from the common solution when forming the first member MA to the common solution when forming the third member MC. In addition, this change is achieved by changing the bending angle of the second member MB to the bending target value θ target 33 is used when bending the first member MA and the third member MC to the bending target value θ target The second member MB, which connects the first member MA and the third member MC, is also bent to the desired bending value θ target Furthermore, the bending angle θ from the first member MA to the second member MB can be f_load and the bending angle θ b_load and the bending angle θ from the second member MB to the third member MC f_load and the bending angle θ b_load It can be smoothly connected to changes in

[0061] <Third embodiment> Fig. 34 is a schematic perspective view of a bending apparatus according to a third embodiment. In the third embodiment, a forming tool 10B, which is a substitute for the forming tool 10A in the second embodiment, forms a plate material OBb, which is a tailored blank material, while feeding it. Note that the control device that controls the forming tool 10B in the third embodiment is the same as the control device 50 in the first embodiment, and is therefore omitted from Fig. 34.

[0062] As shown in FIG. 34, the forming tool 10B of the third embodiment includes, in order from the upstream side in the feed direction parallel to the Y axis, first feed rollers 10c1-10c3, second feed rollers 10d1-10d3, bending forming tools 10e1 and 10e2, and unbending forming tools 10f1 and 10f2.

[0063] FIG. 35 is a schematic cross-sectional view perpendicular to the feed direction of the second feed rollers 10d1-10d3. FIG. 35 shows a schematic view of the cross section d in FIG. 34. In the third embodiment, each of the second feed rollers 10d1-10d3 is a roller that rotates in a direction to feed the plate material OBb in the feed direction. As shown in FIG. 35, the second feed roller 10d3 is arranged so as to be movable along the Z-axis direction. That is, as the second feed roller 10d3 moves along the Z-axis direction, the second feed rollers 10d1-10d3 feed the plate material OBb while bending the plate material OBb at a predetermined angle. Note that the first feed rollers 10c1-10c3 bend the plate material OBb at a smaller angle than the second feed rollers 10d1-10d3 before bending the plate material OBb by the second feed rollers 10d1-10d3.

[0064] Fig. 36 is a schematic cross-sectional view perpendicular to the feed direction of the bending tools 10e1 and 10e2. Fig. 36 shows a schematic view of the cross section e in Fig. 34. The bending tool 10e1 is a roller that rotates in a direction in which the plate material OBb is fed in the feed direction. The bending tool 10e2 bends the plate material OBb fed by the bending tool 10e1 at a bending angle θ f_load The bending tool 10e2 is disposed so as to be rotatable around the Y axis on the cross section e as shown in FIG. 36. Therefore, the bending angle θ f_load is set.

[0065] FIG. 37 is a schematic cross-sectional view of the bending back forming tools 10f1 and 10f2, which is perpendicular to the feed direction. FIG. 37 shows a schematic diagram of the cross section f in FIG. 34. The bending back forming tool 10f1 is a roller that rotates in a direction in which the plate material OBb is fed in the feed direction. The bending back forming tool 10f2 bends the plate material OBb fed by the bending back forming tool 10f1 at a bending back angle θ b_load The bending back tool 10f2 is disposed so as to be rotatable around the Y axis on the cross section f, as shown in FIG. 37. Therefore, the bending back angle θ b_load is set.

[0066] As in the forming apparatus of the third embodiment, the bending tools 10e1 and 10e2 are bent at a bending angle θ f_load Before being formed into the shape, the plate material OBb is bent at a bending angle θ by the first feed rollers 10c1 to 10c3 and the second feed rollers 10d1 to 10d3. f_load The bending may be performed at an angle smaller than the angle . In addition, one of the bending tools 10e1, 10e2 may have a function of conveying the plate material OBb in the feed direction, and the other may not have a conveying function. Similarly, one of the bending tools 10f1, 10f2 may have a function of conveying the plate material OBb in the feed direction, and the other may not have a conveying function. In other embodiments, all of the bending tools 10e1, 10e2 and the bending tools 10f1, 10f2 may have a conveying function, or all of them may not have a conveying function, and the plate material OBb may be conveyed by the first feed rollers 10c1 to 10c3, etc.

[0067] <Fourth embodiment> FIG. 38 is a schematic front view of a bending apparatus 100C of the fourth embodiment. The bending apparatus 100C of the fourth embodiment is a press molding machine including an upper die 10C and a lower die 20C. In the sheet material OBc formed in the fourth embodiment, the first member MA and the second member MB are joined in the ZX plane perpendicular to the depth direction parallel to the Y axis direction. Note that the control device that controls the upper die 10C and the lower die 20C of the fourth embodiment is the same as the control device 50 of the first embodiment, and is therefore omitted in FIG. 38.

[0068] The upper mold 10C is moved along the Z-axis direction by a device not shown. As shown in FIG. 38, the upper mold 10C includes a movable upper mold 10C1, driving devices 10C2 and 10C3, joints 10C4 and 10C5, and cranks 10C6 and 10C7. The movable upper mold 10C1 includes an upper portion 10C1a extending along the X-axis direction, a column portion 10C1b having one end connected to the upper portion 10C1a, a left end portion 10C1c connected to the X-axis negative side of the upper portion 10C1a, and a right end portion 10C1d connected to the X-axis positive side of the upper portion 10C1a. The other end of the column portion 10C1b, which is not connected to the upper portion 10C1a, extends from the center of the upper portion 10C1a in the X-axis direction to the Z-axis negative side. The other end of the left end 10C1c and the right end 10C1d that is not connected to the upper portion 10C1a extends in the negative direction of the Z axis. The length of extension of the left end 10C1c and the right end 10C1d is shorter than the length of the pillar portion 10C1b. A driving device 10C2 is fixed to the lower end of the left end 10C1c. Similarly, a driving device 10C3 is fixed to the lower end of the right end 10C1d.

[0069] The driving device 10C2 supports one end of the joint 10C4 on the negative side of the X-axis so as to be swingable along the X-axis direction. Similarly, the driving device 10C3 supports one end of the joint 10C5 on the positive side of the X-axis so as to be swingable along the X-axis direction. The cranks 10C6 and 10C7 are rod-shaped members extending along the longitudinal direction. As shown in FIG. 38, grooves GR6 and GR7 are formed along the longitudinal direction at one end of the cranks 10C6 and 10C7. The other end of the cranks 10C6 and 10C7, where the grooves GR6 and GR7 are not formed, is supported on the lower end of the column portion 10C1b on the negative side of the Z-axis so as to be rotatable around the Y-axis.

[0070] The other end of the joint 10C4, which is not supported by the driving device 10C2, is supported so as to be able to swing within a groove GR6 formed in a crank 10C6. A pin PN4 formed at the other end of the joint 10C4 engages with the groove GR6. Similarly, the other end of the joint 10C5, which is not supported by the driving device 10C3, is supported so as to be able to swing within a groove GR7 formed in the crank 10C7. A pin PN5 formed at the other end of the joint 10C5 engages with the groove GR7. Since the upper mold 10C has the structure described above, the angle formed between the cranks 10C6, 10C7 and the YZ plane of the lower end of the column portion 10C1b that rotatably supports the cranks 10C6, 10C7 changes depending on the amount of swing of the joints 10C4, 10C5 controlled by the driving devices 10C2, 10C3.

[0071] As shown in FIG. 38, the lower mold 20C includes a fixed lower mold 20C1, driving devices 20C2-20C5, joints 20C6-20C9, and cranks 20C10 and 20C11. The fixed lower mold 20C1 includes a lower portion 20C1a extending along the X-axis direction, a column portion 20Cb2 having one end connected to the lower portion 20C1a, a left end portion 20C1c connected to the X-axis negative side of the lower portion 20C1a, and a right end portion 20C1d connected to the X-axis positive side of the lower portion 20C1a. The other end of the column portion 20C1b that is not connected to the lower portion 20C1a extends from the center of the lower portion 20C1a in the X-axis direction to the Z-axis positive side. The other ends of the left end portion 20C1c and the right end portion 20C1d that are not connected to the lower portion 20C1a extend to the Z-axis positive side. The extension length of the left end 20C1c and the right end 20C1d is greater than the length of the column portion 20Cb2. A driving device 20C2 is fixed to the upper end of the left end 20C1c. A driving device 20C3 is fixed between the upper and lower ends of the left end 20C1c. Similarly, a driving device 20C4 is fixed to the upper end of the right end 20C1d. A driving device 20C5 is fixed between the upper and lower ends of the right end 20C1d.

[0072] The driving device 20C2 supports one end of the X-axis negative side of the joint 20C6 so that it can swing along the X-axis direction. The driving device 20C3 supports one end of the X-axis negative side of the joint 20C7 so that it can swing along the X-axis direction. Similarly, the driving device 20C4 supports one end of the X-axis positive side of the joint 20C8 so that it can swing along the X-axis direction. The driving device 20C5 supports one end of the X-axis positive side of the joint 20C9 so that it can swing along the X-axis direction.

[0073] The cranks 20C10 and 20C11 are rod-shaped members extending along the longitudinal direction. As shown in FIG. 38, the cranks 20C10 and 20C11 have grooves GR10 and GR11 formed along the longitudinal direction at one end thereof. The other end of the crank 20C10 where the groove GR10 is not formed is supported rotatably around the Y axis at the other end of the joint 20C6 that is not supported by the drive unit 20C2. Similarly, the other end of the crank 20C11 where the groove GR11 is not formed is supported rotatably around the Y axis at the other end of the joint 20C8 that is not supported by the drive unit 20C4.

[0074] The other end of the joint 20C7, which is not supported by the driving device 20C3, is supported so as to be able to swing in a groove GR10 formed in the crank 20C10. Specifically, a pin PN7 formed at the other end of the joint 20C7 is engaged with the groove GR10. Similarly, the other end of the joint 20C9, which is not supported by the driving device 20C5, is supported so as to be able to swing in a groove G11 formed in the crank 20C11. A pin PN9 formed at the other end of the joint 20C9 is engaged with the groove GR11. Since the lower mold 20C has the structure described above, the angle formed between the crank 20C10 and the XY plane of the upper end of the joint 20C6, which rotationally supports the other end side of the crank 20C10, changes depending on the amount of swing of the joints 20C6 and 20C7 controlled by the driving devices 20C2 and 20C3. Similarly, the angle formed between crank 20C11 and the XY plane of the upper end of joint 20C8, which rotatably supports the other end of crank 20C11, changes depending on the amount of swing of joints 20C8, 20C9 controlled by drive devices 20C4, 20C5.

[0075] FIG. 39 shows the bending target value θ target FIG. 39 is an explanatory diagram of four bending target values ​​θ target In the fourth embodiment, four bending target values ​​θ target In the fourth embodiment, the drive control unit 52 controls the swing amount of the six drive devices 10C2, 10C3, and 20C2 to 20C5 to change the bending angle θ f_load Bend the target value θ target The drive control unit 52 also controls the bending back angle θ b_load Bend the target value θ target Make it smaller than.

[0076] 40 is a schematic front view of the bending apparatus 100C during bending. The drive control unit 52 uses the prediction model MD to calculate the bending angle θ f_load The drive control unit 52 determines the bending angle θ f_loadThe driving devices 10C2, 10C3, and 20C2 to 20C5 are controlled so that the plate material OBc can be bent at the bottom dead center of the forming. As shown in FIG. 40, the driving device 10C2 swings the joint 10C4 in the positive direction of the X-axis. The driving device 10C3 swings the joint 10C5 in the negative direction of the X-axis. As a result, the angle between the cranks 10C6, 10C7 and the pillar portion 10C1b becomes the bending angle θ f_load In the same manner, the driving device 20C2 swings the joint 20C6 in the positive direction of the X-axis. The driving device 20C3 swings the joint 20C7 in the negative direction of the X-axis. The driving device 20C4 swings the joint 20C8 in the negative direction of the X-axis. The driving device 20C5 swings the joint 20C9 in the positive direction of the X-axis. As a result, the angle between the crank 20C10 and the upper end of the joint 20C6 changes to a bending angle θ f_load In the same manner, the angle between the crank 20C11 and the upper end of the joint 20C8 changes to a bending angle θ f_load changes to.

[0077] 41 is a schematic front view of the bending apparatus 100C during bending back. b_load The drive devices 10C2, 10C3, and 20C2 to 20C5 are controlled so that the plate material OBc can be bent back and formed in the desired manner. As shown in FIG. 41, the drive device 10C2 swings the joint 10C4 in the negative direction of the X-axis from the state during bending. The drive device 10C3 swings the joint 10C5 in the positive direction of the X-axis. As a result, the angle formed between the cranks 10C6, 10C7 and the column portion 10C1b becomes the bend-back angle θ b_load In the same manner, the driving device 20C2 swings the joint 20C6 in the positive and negative directions along the X-axis from the state during bending. The driving device 20C3 swings the joint 20C7 in the positive direction along the X-axis. The driving device 20C4 swings the joint 20C8 in the positive direction along the X-axis. The driving device 20C5 swings the joint 20C9 in the negative direction along the X-axis. As a result, the angle between the crank 20C10 and the upper end of the joint 20C6 becomes the bending back angle θ b_loadIn the same manner, the angle between the crank 20C11 and the upper end of the joint 20C8 changes to the bending back angle θ b_load When the upper die 10C and the lower die 20C are separated from each other from the state shown in FIG. 41, the plate material OBc is bent to the bending target value θ target It is molded into.

[0078] The press molding machine, which is the bending apparatus 100C of the fourth embodiment, may perform bending and unbending at a plurality of positions on the plate material OBc to be bent. f_load and the bending angle θ b_load The clamps 10C6, 10C7, 20C10, and 20C11 for setting the above may be set freely.

[0079] <Modifications of the embodiment> The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit of the present invention, for example, the following modifications are possible: In the above-described embodiment, a part of the configuration realized by hardware may be replaced by software, and conversely, a part of the configuration realized by software may be replaced by hardware.

[0080] In the above embodiment, the bending apparatus 100 performs bending and unbending after bending. Although an example of the bending apparatus has been described, the configuration of the bending apparatus can be modified. As the bending apparatus, a known apparatus can be applied as long as it can perform bending and bending back on the tailored blank material. The bending apparatus 100 does not need to include the control device 50, the first camera 30, and the second camera 40. The bending apparatus of the modified example may be configured, for example, with an upper mold 10 and a lower mold 20 that are driven in response to a control signal from another apparatus. In addition, the tailored blank material may be formed by the bending angle and the bending back angle set by the user without using the prediction model MD in bending and bending back forming. In addition, even in the processing in which the prediction model MD is used, the prediction model MD may not be corrected. In addition, the correction of the prediction model MD may be performed by comparing the forming simulation value with the predicted value, rather than comparing the actual value with the predicted value.

[0081] Fig. 42 is a flowchart of a bending method according to a modified example. The processes in steps S11 to S14 of the bending flow shown in Fig. 42 are the same as those in steps S1 to S4 of the bending flow of the above embodiment (Fig. 13). As shown in Fig. 42, the bending flow does not need to include a process of correcting the prediction model MD.

[0082] In the above embodiment, the bending apparatus 100 and the like are described using an orthogonal coordinate system CS defined by the X-axis, Y-axis, and Z-axis, but the definition of the coordinate system can be modified. In the above first and fourth embodiments, the plate materials OB, OBc are processed using the upper mold 10, 10C and the lower mold 20, 20C that operate along the Z-axis parallel to the vertical direction, but the plate materials OB, OBc may be formed by a forming mold that moves in a horizontal direction such as the X-axis or Y-axis. In addition, a tailored blank material may be processed by a bending apparatus that includes a forming mold other than the upper mold 10, 10C and the lower mold 20, 20C.

[0083] Although the present aspect has been described above based on the embodiment and modified examples, the above-mentioned embodiment of the aspect is intended to facilitate understanding of the present aspect and does not limit the present aspect. The present aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents are included in the present aspect. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate. [Explanation of symbols]

[0084] 10,10C…upper mold 10A, 10B…Molding tool 10C1…Movable upper mold 10C1a…Upper part of upper die 10C1b…Column part of upper die 10C1c…Left end of upper die 10C1d…Right end of upper die 10C2, 10C3...Upper die drive unit 10C4, 10C5...Upper joint 10C6, 10C7...Upper crank 10a1 to 10a3: Upper rollers (transport section) 10b1 to 10b3: Lower rollers (transport section) 10c1~10c3...First feed roller 10d1~10d3...Second feed roller 10e1, 10e2... Bending tool 10f1, 10f2... Bending tool 11,13…Outer upper mold 12...Central upper type 20,20C…lower mold 20C1…Fixed lower mold 20C10, 20C11…Lower crank 20C1a…Lower part of the lower die 20C1b…Column part of lower die 20C1c…Left end of lower die 20C1d…Right end of lower die 20C2~20C5…Lower die drive unit 20C6~20C9…Lower die joint 20Cb2…Column part of lower die 21…Outer lower mold 22…Central lower die 30…First camera (bending angle acquisition unit) 40…Second camera (bending angle acquisition unit) 50...Control device 51…CPU 52...Drive control unit 53...Calculation section (condition calculation section) 54…Compensation section 55…Settings section 56...Storage section 57…Communications Department 58...Output section 59...Input section 100,100C…Forming equipment C A …Correction coefficient for the first component C B …Correction coefficient for second component CBa: Curve of the first component CBb,C PB …Curve of the second member CP1,CP2…intersection CS...Cartesian coordinate system DR11~DR13, DR21~DR23...Vertical direction FR…Body frame GR6,GR7,GR10,GR11…Groove MA: First component MB: Second member MC: Third component MD: Predictive model OB…Plate material OB1, OB2: Tailored blank material OB, OBa, OBb, OBc: Plate material (tailored blank material) PA…Section PB…Section PC…Section PN4, PN5, PN7, PN9... pins PTf: Position of bending tool PTb: Position of bending tool RF…Rocker frame UF…Upper frame θ f_load …Bending angle θ b_load …Bending angle θ target …Bending target value θ unload_A …Bending angle of the first component after molding (first angle) θ unload_B …Bending angle of the second part after forming (second angle)

Claims

1. A bending forming apparatus, a bending forming section that bends a tailored blank material in which plate materials having different bending strengths are joined in a predetermined direction; a bending-back forming section that bends the tailored blank material bent by the bending forming section back in a direction opposite to the predetermined direction; a condition calculation unit that calculates a bend angle larger than a target bend value and a bend-back angle smaller than a target bend value according to a target bend value after forming of the tailored blank material; Equipped with The condition calculation unit When the tailored blank material is formed by joining a first member and a second member, a first angle, which is an angle of the first member after forming, determined by the bending angle and the bending back angle of the first member; a second angle, which is an angle of the second member after forming, determined by the bending angle and the bending back angle of the second member; A prediction model is created to predict a forming angle, which is the angle of the tailored blank material after forming, using the bending forming unit bends the tailored blank material to the bending angle calculated by the condition calculation unit, The bending forming device, wherein the bend-back forming unit bends back the tailored blank material bent by the bend forming unit so as to achieve the bend-back angle calculated by the condition calculation unit.

2. The bending apparatus according to claim 1, further comprising: A bending forming apparatus comprising: a correction unit that corrects the prediction model using a predicted value of the forming angle obtained using the prediction model and a measured value of the forming angle.

3. The bending apparatus according to claim 2, further comprising: A bending angle acquisition unit that acquires the first angle and the second angle, A bending forming apparatus, wherein the correction unit corrects the prediction model using the first angle and the second angle acquired by the bending angle acquisition unit.

4. The bending apparatus according to any one of claims 1 to 3, further comprising: a conveying section that conveys the tailored blank material in a feed direction, the tailored blank material is formed in the order of the first member, the second member, and the third member by being joined in the feed direction in that order, When an angle of the third member after forming, which is determined by the bending angle and the bending-back angle of the third member, is defined as a third angle, The bent forming portion and the bent back forming portion are forming the first part at the bend angle and the unbend angle using the predictive model created using the first angle and the second angle; forming the third part at the bending angle and the unbending angle using the predictive model created using the second angle and the third angle; A bending forming device that gradually changes the second member from the bending angle and the bend-back angle when forming the first member to the bending angle and the bend-back angle when forming the third member by using the second angle as the feed rate by the conveying section increases.

5. A bending method comprising: a bending forming process in which a tailored blank material in which plate materials having different bending strengths are joined is bent in a predetermined direction; a bending back process of bending back the tailored blank material bent in the bending process in a direction opposite to the predetermined direction; a condition calculation step of calculating a bending angle larger than a bending target value after forming of the tailored blank material and a bending back angle smaller than the bending target value; Equipped with The condition calculation step includes: When the tailored blank material is formed by joining a first member and a second member, a first angle, which is an angle of the first member after forming, determined by the bending angle and the bending back angle of the first member; a second angle, which is an angle of the second member after forming, determined by the bending angle and the bending back angle of the second member; A prediction model is created to predict a forming angle, which is the angle of the tailored blank material after forming, using The bending step includes bending the tailored blank material to the bending angle calculated in the condition calculation step, A bending method, comprising: bending back the tailored blank material bent in the bending forming step so as to achieve the bend-back angle calculated in the condition calculation step.

6. A computer program comprising: A bending forming function that bends tailored blank materials, which are made by joining plate materials with different bending strengths, in a specified direction. a bending-back forming function for bending back the tailored blank material bent by the bending forming function in a direction opposite to the predetermined direction; a condition calculation function for calculating a bending angle larger than a bending target value after forming of the tailored blank material and a bending back angle smaller than the bending target value; This is realized in bending equipment, The condition calculation function is When the tailored blank material is formed by joining a first member and a second member, a first angle, which is an angle of the first member after forming, determined by the bending angle and the bending back angle of the first member; a second angle, which is an angle of the second member after forming, determined by the bending angle and the bending back angle of the second member; A prediction model is created to predict a forming angle, which is the angle of the tailored blank material after forming, using the bending function bends the tailored blank material to the bending angle calculated by the condition calculation function; The bend-back forming function is a computer program for bending back the tailored blank material bent by the bending forming function so as to achieve the bend-back angle calculated by the condition calculation function.

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