Bending method

Abstract

To provide a bending method which can easily perform calibration according to a processing position of a table to suppress cost increase of a bending product.SOLUTION: A bending method uses a press-brake with a first butting part (25L) and a second butting part (25R) respectively having a first butting surface and a second butting surface in which a back-gage device (2) is included to capable of moving the first and second butting parts (25L, 25R) in an orthogonal direction of a bending line (BL) and performing approximating movement and separation movement along the bending line (BL). When a bending material (5) includes a basic part and a butting piece part to be a bending product, bending processing is repeated a specified number of times while shifting a position of a material bending line per processing in which the first and second butting parts (25L, 25R) are positioned so that the material bending line of the bending material (5) is aligned with the bending line (BL) where the butting piece part is butted to the first butting surface and the basic part is butted to the second butting surface (25Ra).SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a bending method. [Background technology]

[0002] Patent Document 1 describes a bending method for forming a curved surface such as a conical surface by bending a sheet metal material to be bent using a press brake. The press brake used in the bending method described in Patent Document 1 is equipped with a butting device (hereinafter referred to as a backgauge) that operates to assist the bending of a curved surface. This back gauge has a pair of guide members each having abutment surfaces positioned on the same abutment line in a plan view, and a straight guide beam that supports the pair of guide members, extends to the left and right, and is arranged horizontally.

[0003] The pair of guide members are movable toward and away from each other on the guide beam, which can be tilted at any angle relative to the bending position (line) extending to the left and right of the press brake in a plan view. This allows the angle between the abutment line and the bending line of the pair of guide members in a plan view to be set to any angle.

[0004] The blank to be bent is formed into a shape having a base portion that will become the bent product and an auxiliary abutment piece that extends outward from the outer shape of the base portion. The outer edge shape of the auxiliary abutment piece is formed so that it can make line contact with both abutment surfaces of a pair of guide members of the press brake in a plan view.

[0005] When using the above-mentioned backgauge and bending material to process a specified range of the bending material into a curved surface such as a conical surface, a pair of guide members are set in advance so that when the edges of the auxiliary abutment pieces are abutted against their abutment surfaces so that they make line contact in a plan view, the bending line of the bending material and the bending position of the press brake coincide. Specifically, the angle of inclination of the guide beam relative to the bending line and the left-right positions of the pair of guide members on the guide beam are set to predetermined angles and positions. This allows the workpiece to be bent along the desired bending line simply by butting it against the butting surface. Hereinafter, the bending line on the workpiece will be referred to as the workpiece bending line to distinguish it from the bending line on the press brake side.

[0006] By gradually changing the inclination angle of the guide beam set as described above and the left-right positions of the pair of guide members on the guide beam, and performing multiple bending processes on the curved surface formation area of ​​the bending material, it is possible to form curved surfaces such as conical surfaces. Then, in the final stage of the bending process, the auxiliary abutment piece is cut off to obtain a bent product having a desired curved surface shape. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 5743322 Summary of the Invention [Problem to be solved by the invention]

[0008] In the conventional bending method using a backgauge and bending material described in Patent Document 1, the bending position on the table must be adjusted left and right depending on the front-to-rear distance between the material bending line and the abutting edge of the auxiliary abutment piece. If the bending position on the table is not centered but is offset to the left or right, corrections such as the amount of push-in must be made to eliminate the imbalance in the processing load on the press brake. However, this correction depends heavily on the operator's experience and is not necessarily easy. Furthermore, if the curved surface to be formed is not a conical surface, it becomes necessary to form multiple straight edge portions with different angles on the edge of the auxiliary abutment piece, which results in the auxiliary abutment piece being cut off and not contributing to the product shape, resulting in a decrease in the utilization efficiency of the bending material and an increase in the cost of the bent product. Therefore, there is a need for a bending method that allows easy correction according to the processing position of the table and suppresses increases in the cost of the bent product. [Means for solving the problem]

[0009] In order to solve the above problems, one embodiment of the present invention has the following configuration. 1) A press brake is used that has a first abutting section and a second abutting section, each having a first abutting surface and a second abutting surface as abutting surfaces, and is equipped with a backgauge device that can move the first abutting section and the second abutting section independently in a direction perpendicular to a bending line of a bending process and can move them toward and away from each other along the bending line, A bending material to be formed into a bent product having a curved surface by bending is shaped to have a base portion which is a portion to be formed into the bent product and a butting piece portion extending outward from the base portion, The first abutting portion and the second abutting portion are arranged such that the abutting piece portion is positioned on the first abutting surface. Point contact with the tip of and at the same time, the base portion is pressed against the second abutting surface. Point contact In this bending method, the bending line of the material to be bent is positioned to coincide with the bending line in the butted state, and the bending is performed a predetermined number of times while shifting the position of the material bending line for each bending operation, thereby forming the curved surface. 。 [Effects of the Invention]

[0010] According to one aspect of the present invention, correction can be easily made according to the processing position of the table, and an increase in the cost of the bent product can be suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a right side view of a press brake 1 used when performing the bending method of the present invention. [Figure 2] FIG. 2 is a top view of the backgage device 2 provided in the press brake 1. [Figure 3] FIG. 3 is a block diagram of the control device 16 and the backgauge device 2 of the press brake 1. [Figure 4] FIG. 4 is a perspective view showing a bent product 5A bent using the press brake 1 according to the bending method of the first embodiment. [Figure 5] FIG. 5 is a plan view showing an expanded material 505 in which the bent product 5A is expanded. [Figure 6] FIG. 6 is a diagram for explaining the material folding lines (B201 to B211, B401 to B411) in the unfolded material 505. As shown in FIG. [Figure 7] FIG. 7 is a plan view showing a bending material 5 to be bent by the bending method of the first embodiment to obtain a bent product 5A. [Figure 8] FIG. 8 is a first diagram for explaining the manner in which the workpiece 5 is butted in the bending method of the first embodiment. [Figure 9] FIG. 9 is a second diagram for explaining the manner in which the workpiece 5 is butted in the bending method of the first embodiment. [Figure 10] FIG. 10 is a third diagram for explaining the manner in which the workpiece 5 is butted in the bending method of the first embodiment. [Figure 11] FIG. 11 is a diagram for explaining another mode different from the abutting mode shown in FIG. [Figure 12] FIG. 12 is a perspective view showing a bent product 6A bent by the bending method of Example 2. As shown in FIG. [Figure 13A] FIG. 13A is a plan view showing a bending material 6 for obtaining a bent product 6A by the bending method of Example 2. FIG. [Figure 13B] FIG. 13B is a plan view showing a bending material 7, which is a modified example of the bending material 6. As shown in FIG. [Figure 14] FIG. 14 is a diagram for explaining the manner in which the workpiece 6 is butted in the bending method of the second embodiment. [Figure 15] FIG. 15 is a perspective view showing a bent product 8A bent by the bending method of Example 3. As shown in FIG. [Figure 16A]FIG. 16A is a plan view showing a bending material 8 for obtaining a bent product 8A by the bending method of the third embodiment. [Figure 16B] FIG. 16B is a plan view showing a bending material 9, which is a modified example of the bending material 8. As shown in FIG. [Figure 17] FIG. 17 is a diagram for explaining the manner in which the workpiece 8 is butted in the bending method of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Example 1 First, a press brake 1 for performing a bending method according to an embodiment of the present invention will be described with reference to Figs. 1 to 3. Fig. 1 is a right side view of the press brake 1 used when performing the bending method of the present invention. Fig. 2 is a top view of a backgage device 2 provided in the press brake 1. Fig. 3 is a block diagram of a control device 16 of the press brake 1 and the backgage device 2. In the following description, the front-rear, top-bottom, and bottom-up directions are defined as the directions indicated by arrows in Fig. 1. In Fig. 1, the left direction is the direction into the paper, and the right direction is the direction towards you.

[0013] As shown in Figures 1 and 2, the press brake 1 includes a pair of left and right side plates 11, a lower table 12, an upper table 14, a backgauge device 2, a control device 16, an input device 17, and an output device 18.

[0014] The lower table 12 is disposed at the lower portion between the pair of side plates 11, 11, and the upper table 14 is disposed at the upper portion between the pair of side plates 11, 11 so as to face the lower table 12 in the vertical direction. One of the lower table 12 and the upper table 14 is fixed, and the other is raised and lowered relative to the other by a drive mechanism (not shown). For example, the lower table 12 is fixed, and the upper table 14 is raised and lowered so as to move toward and away from the lower table 12.

[0015] A die 13, which is a lower die for bending, is detachably attached to the upper surface of the lower table 12. A punch 15, which is an upper die that pairs with the die 13, is detachably attached to the underside of the upper table 14. When the press brake 1 is stationary, the die 13 and punch 15 are spaced apart in the vertical direction. With this configuration, the press brake 1 can lower the punch 15 between the die 13 and the punch 15 to bend the sheet metal material 5 that is inserted from the front and placed on the top surface of the die 13, in cooperation with the die 13. 1 and 2, the position at which the blank 5 is bent in the press brake 1 is indicated by a chain line as a bending line BL.

[0016] The backgauge device 2 is a so-called butting device, which determines the position in the front-rear direction of the workpiece 5 to be bent by butting during bending. As shown in FIGS. 1 and 2, the backgage device 2 has a support beam 21, a left gage section 22L, and a right gage section 22R. The support beam 21 is a columnar member disposed between a pair of left and right side plates 11, 11 so as to extend in the left-right direction.

[0017] As shown in FIG. 2, the left gauge section 22L and the right gauge section 22R are supported independently by a support beam 21 so as to be movable in the left-right direction (see arrow DR1). A first direction left drive unit 21LK that moves the left gauge unit 22L left and right, and a first direction right drive unit 21RK that moves the right gauge unit 22R left and right are installed on the support beam 21. Hereinafter, the left and right direction will also be referred to as the first direction, and the front and rear direction will also be referred to as the second direction.

[0018] The left gauge portion 22L and the right gauge portion 22R are assembly members that extend in the front-rear direction. The left gauge section 22L has a left gauge base 23L, a left slider 24L, and a second direction left drive section 23LK. The left gauge base 23L is a rail-shaped member supported by the support beam 21 so as to be movable in the left-right direction. The left slider 24L is supported by the left gauge base 23L so as to be movable in the front-rear direction (see arrow DR2L). The second direction left driver 23LK is provided on the left gauge base 23L and moves the left slider 24L in the front-rear direction.

[0019] The right gauge section 22R has a right gauge base 23R, a right slider 24R, and a second direction right drive section 23RK. The right gauge base 23R is a rail-shaped member supported by the support beam 21 so as to be movable in the left-right direction. The right slider 24R is supported by the right gauge base 23R so as to be movable in the front-rear direction (see arrow DR2R). The second direction right drive unit 23RK is provided on the right gauge base 23R and moves the right slider 24R in the front-rear direction.

[0020] As shown in FIG. 3, the first direction left drive section 21LK, the first direction right drive section 21RK, the second direction left drive section 23LK, and the second direction right drive section 23RK are collectively referred to as a gauge drive group 2KG.

[0021] As shown in FIGS. 1 and 2, the left slider 24L and the right slider 24R have a left abutment portion 25L and a right abutment portion 25R that protrude forward, respectively. The left abutment surface 25La, which is the front end face of the left abutment portion 25L, and the right abutment surface 25Ra, which is the front end face of the right abutment portion 25R, are always vertical and parallel to the bending line BL, which is represented by a straight line extending in the left-right direction, regardless of the front-to-back positions of the left slider 24L and the right slider 24R. The left abutment portion 25L and the right abutment portion 25R are also referred to as the first abutment portion 25L and the second abutment portion 25R, respectively. The left abutment surface 25La and the right abutment surface 25Ra are also referred to as the first abutment surface 25La and the second abutment surface 25Ra, respectively.

[0022] As shown in Fig. 3, the control device 16 has a central processing unit (CPU) 161, a memory unit 162, a gauge position acquisition unit 163, a gauge drive unit 164, and an output unit 165. Fig. 3 shows the control system of the backgage device 2, and the drive system that performs the bending process of the press brake 1 is omitted. The storage unit 162 stores bending information J1 and bending programs JP for obtaining various bent products including a bent product 5A described below.

[0023] Specifically, the bending information J1 is the front-rear and left-right positions of the left slider 24L and the right slider 24R associated with each bending line (such as material bending line B401 in FIG. 7) of the bending workpiece 5. The bending program JP defines the processing order of a plurality of preset bending lines (such as material bending lines B201 to B211 in FIG. 7). These will be described in detail later.

[0024] The gauge position acquisition unit 163 acquires the material bending line for the next bending process from among multiple material bending lines and the positions of the left slider 24L and the right slider 24R (hereinafter also referred to as gauge positions) by referring to the memory unit 162 in accordance with the procedure of the bending process program JP. The gauge driving unit 164 controls the operation of the gauge driving group 2KG, and positions the left slider 24L and the right slider 24R at the gauge positions acquired by the gauge position acquiring unit 163 during bending.

[0025] The output unit 165 outputs to the output device 18 the operating status of the control device 16, processing information on the press brake 1 side such as the set status of the backgauge device 2, and processing information to be provided to the worker, as visual information or auditory information.

[0026] An input device 17 is connected to the control device 16. The input device 17 also has an external communication function, and transmits operation instructions input by an operator or operation instructions received from the outside via communication or the like to the control device 16. In Fig. 1, the input device 17 is integrated with an output device 18 equipped with a display, a speaker, etc.

[0027] Next, a bending method of Example 1, in which a press brake 1 is used to form a curved surface region of a bent product having a curved surface, will be described. The bent product is bent product 5A shown in Fig. 4, and the curved surface is a part of a conical surface. The material before bending, obtained by unfolding bent product 5A, is unfolded material 505 shown in Fig. 5. That is, Fig. 4 is a perspective view showing bent product 5A bent by the bending method of Example 1 using press brake 1. Fig. 5 is a plan view showing unfolded material 505 obtained by unfolding bent product 5A.

[0028] 4, bent product 5A has arcuate curved edge 51A at one end, straight edge portions 53A, 54A, and 55A at the other end, and five side portions AR1A to AR5A connecting them. In other words, bent product 5A presents a generally hood-shaped semi-cylindrical body with sides that smoothly connect the arcuate end portion at one end and the rectangular end portion at the other end, including the curved surface.

[0029] The side portions AR1A and AR5A are formed as substantially triangular flat plates with one end being corners P12A and P61A, which are both ends of the curved edge portion 51A, and the other end being straight edges 53A and 55A, respectively. The side portion AR3A is formed as a generally triangular flat plate having one end at a position P51A in the center of the curved edge portion 51A and the other end at a straight edge portion 54A. The side portion AR2A is formed by a curved surface that is a part of a conical surface, with one end being a semicircular arc portion between the corner P12A and the position P51A at the curved edge portion 51A and the other end being a connection point P34A where the straight edge portion 53A and the straight edge portion 54A are connected. The side portion AR4A is formed by a curved surface that is a part of a conical surface, with one end being a semicircular arc portion between the corner P61A of the curved edge portion 51 and the position P51A, and the other end being a connection point P45A where the straight edge portion 54A and the straight edge portion 55A are connected.

[0030] The expanded material 505 obtained by expanding the bent product 5A is identified before and after expansion by a reference numeral obtained by removing the "A" from the end of the reference numeral attached to the bent product 5A. 5, the boundaries between the side portions AR1 to AR5 are indicated by dashed dotted lines. Specifically, the boundary between the side portions AR1 and AR2 is indicated by boundary line LN1, the boundary between the side portions AR2 and AR3 is indicated by boundary line LN2, the boundary between the side portions AR3 and AR4 is indicated by boundary line LN3, and the boundary between the side portions AR4 and AR5 is indicated by boundary line LN4.

[0031] The bent product 5A is obtained by processing the side portions AR2 and AR4 of the unfolded material 505 into curved surfaces. To achieve this, multiple bending lines are set for the side portions AR2 and AR4, and bending is performed with a slight bending angle at each bending line. 6 shows an example in which a plurality of material folding lines are set for the side portions AR2 and AR4. That is, FIG. 6 is a diagram for explaining material folding lines (B201 to B211, B401 to B411) in the unfolded material 505.

[0032] In this example, the side portions AR2 and AR4 are each divided into 10 parts at an angle θ, and imaginary material bending lines B201 to B211 are set on the side portion AR2, and imaginary material bending lines B401 to B411 are set on the side portion AR4. The material bending lines B201 and B211 coincide with the boundary lines LN1 and LN2, respectively, and the material bending lines B401 and B411 coincide with the boundary lines LN3 and LN4, respectively. If the side portions AR2A and AR4A of the bent product 5A are conical surfaces, the material bending lines B201 to B211 intersect at one point in the lower part of FIG. 6, and the material bending lines B401 to B411 intersect at one point in the lower part of FIG.

[0033] In the bending method of the embodiment of the present invention, the bending material for obtaining the bent product 5A is a bending material 5 having a basic portion 50 corresponding to the unfolded material 505 and abutment pieces 57 and 58 extending outward from the basic portion 50. The base portion 50 is the portion that will become the bent product 5A, and the abutting pieces 57 and 58 are portions that are cut off in the final stage of forming the bent product 5A. Hereinafter, the cut abutment piece 57 and the abutment piece 58 will be collectively referred to as a abutment piece portion 50h (see FIG. 7). The abutment piece 57 will also be referred to as a first abutment piece 57, and the abutment piece 58 will also be referred to as a second abutment piece 58.

[0034] Fig. 7 is a plan view showing the bending workpiece 5. More specifically, Fig. 7 is a plan view showing the bending workpiece 5 to be bent by the bending method of the embodiment to obtain a bent product 5A. In the bending workpiece 5 of Fig. 7, imaginary workpiece bending lines B201 to B211, B401 to B411 are shown by dashed lines, just like in the unfolded workpiece 505.

[0035] In the bending material 5, the abutment pieces 57, 58 are attached to the side edge portions 52, 56 at positions closer to the curved edge portion 51 side. The abutting piece 57 has a triangular shape with a tip serving as an abutting apex 571 and a pair of side sides serving as side sides 572 and 573 . The abutting piece 58 has a triangular shape with a tip serving as an abutting apex 581 and a pair of side sides serving as side sides 582 and 583 . The abutment apexes 571 and 581 may be pointed or may be formed in an arc shape as in this example.

[0036] The abutment pieces 57, 58 are cut off from the side edge portions 52, 56, respectively, in the final stage of the forming process of the bent product 5A. Therefore, to facilitate this cutting, slits 57S, 58S are formed to narrow the portions connected to the side edge portions 52, 56. Of the triangular sides 572, 573 of the abutting piece 57, the side 572 on the straight edge 53 side may be parallel to the boundary line LN3, i.e., the material bending line B401. Of the triangular sides 582, 583 of the abutting piece 58, the side 582 on the straight edge 55 side may be parallel to the boundary line LN2, i.e., the material bending line B211. In this example, the bending blank 5 has a bilaterally symmetrical shape in FIG. 7.

[0037] 7, connection points P34 and P45 are rounded in an arc shape. The connection points between both ends of the arc shape of connection point P34 and straight edges 53 and 54 are connection points P341 and P342, respectively, and the connection points between both ends of the arc shape of connection point P45 and straight edges 54 and 55 are connection points P451 and P452, respectively. The boundary lines LN1 and LN2 have connection points P341 and P342 as their end points, respectively, and the boundary lines LN3 and LN4 have connection points P451 and P452 as their end points, respectively.

[0038] The storage unit 162 of the control device 16 stores in advance the bent product obtained by bending, the bending material for obtaining the bent product, and the procedure for bending the bending material in association with each other. For example, when the above-described bent product 5A is to be obtained, bending material information that specifies the bending material 5, such as the outer shape, dimensions, and material, is stored in advance. The output unit 165 of the control device 16 displays on the output device 18 bending blank information of the bending blank to be used in the next bending process.

[0039] The memory unit 162 also stores gauge position information J2, which includes position information of the left slider 24L and the right slider 24R of the backgauge device 2, corresponding to the material bending lines B201 to B211, B401 to B411, respectively, when performing bending processing (see Figure 3). Furthermore, the storage unit 162 stores planar images of the state in which the bending material 5 abuts against the left slider 24L and the right slider 24R during bending at each of the material bending lines B201 to B211 and B401 to B411 as support information for the worker.

[0040] The bending program JP stored in the storage unit 162 defines at least the order in which a plurality of material bending lines are to be bent.

[0041] The configuration of the press brake 1 described above and a method for bending the workpiece 5 based on information previously stored in the storage unit 162 will be described with reference to Figs. 8 to 10. Fig. 8 is a first diagram for illustrating the butting behavior of the workpiece 5 in the bending method of the first embodiment. Fig. 9 is a second diagram for illustrating the butting behavior of the workpiece 5 in the bending method of the first embodiment. Fig. 10 is a third diagram for illustrating the butting behavior of the workpiece 5 in the bending method of the first embodiment.

[0042] First, as shown in FIG. 8, bending is performed on the material bending line B411 of the bending material 5 based on instructions from the bending program JP. The gauge position acquisition unit 163 acquires the gauge position information J2 stored in the storage unit 162 when bending the material bending line B411. The gauge position information J2 includes, for example, the distance DLa, the distance Da, and the distance La shown in Fig. 8. These are pieces of information that determine the setting state of the backgauge device 2 when bending the bending workpiece 5 at the workpiece bending line B411.

[0043] The distance DLa is the distance in the front-to-rear direction from the left abutment surface 25La to the bending line BL in a top view. The distance Da is the distance in the front-to-rear direction between the left abutment surface 25La and the right abutment surface 25Ra in a top view. The distance La is the distance in the left-to-right direction in a top view between the abutment point P57 and the abutment point P23t when the abutment piece 57 of the bending material 5 abuts against the left abutment surface 25La at the abutment point P57 of the abutment apex 571 and the connection point P23 abuts against the right abutment surface 25Ra at the abutment point P23t. In this abutting state, the distance DLa, the distance Da, and the distance La are set so that the workpiece bending line B411 of the bending workpiece 5 coincides with the bending line BL of the press brake 1.

[0044] That is, an operator or a robot hand butts the butt piece 57 of the bending workpiece 5 and the connection point P23, which is the convex tip of the base portion 50 of the bending workpiece 5, against the left butt surface 25La of the left butt portion 25L and the right butt surface 25Ra of the right butt portion 25R, respectively, of different butt portions. As a result, the workpiece bending line B411 coincides with the bending line BL of the press brake 1, and the bending workpiece 5 is set.

[0045] Then, when the worker commands the bending operation using a foot switch (not shown) or the like, the CPU 161 operates the lifting drive system (not shown) based on the bending information J1 and the bending program JP to lower the upper table 14 and perform bending at a predetermined bending angle for the material bending line B411 of the bending material 5.

[0046] In the same manner, bending is performed on the plurality of material folding lines of the side portion AR4 in order. For example, when bending is performed at the kth (k is an integer of 2 to 10) material bending line B4k among the material bending lines B401 to B411, the material bending line B4k comes to an abutting state as shown in Fig. 9. Fig. 9 is a second diagram for explaining the abutting state of the bending material 5 in the bending method of the embodiment.

[0047] When bending the material bending line B4k, the gauge position acquisition unit 163 acquires the gauge position information J2 stored in the storage unit 162 and linked to the material bending line B4k. Specifically, these are the distances DLk, Dk, and Lk shown in Fig. 9. These are information that determines the setting state of the backgauge device 2 when bending the bending workpiece 5 at the workpiece bending line B4k.

[0048] The distance DLk is the distance in the front-to-rear direction from the left abutment surface 25La to the bending line BL in a top view. The distance Dk is the distance in the front-to-rear direction between the left abutment surface 25La and the right abutment surface 25Ra in a top view. The distance Lk is the distance in the left-to-right direction in a top view between the abutment point P57 and the abutment point P23t when the abutment piece 57 of the bending workpiece 5 abuts against the left abutment surface 25La at the abutment point P57 and the connection point P23 abuts against the right abutment surface 25Ra at the abutment point P23t.

[0049] The distance Lk is set in advance based on the widths of the left and right abutment portions 25L and 25R in the left-right direction so that the abutment piece 57 and the connection point P23 are reliably abutted against the left abutment surface 25La and the right abutment surface 25Ra, respectively. The same applies to distances Lb and Lb1, which correspond to the distance La and will be described later.

[0050] The distances DLk, Dk, and Lk are set so that when the connection point P23 of the bending material 5 is abutted against the right abutment surface 25Ra and the abutment tip 571 of the abutment piece 57 in the bending material 5 is abutted against the left abutment surface 25La, the material bending line B4k of the bending material 5 coincides with the bending line BL of the press brake 1.

[0051] When the worker instructs bending using a foot switch (not shown) or the like with the bending material 5 in the butted state shown in Figure 9, the CPU 161 lowers the upper table 14 using a lifting and lowering drive system (not shown) based on the bending processing information J1 and the bending processing program JP, and performs bending processing at a predetermined bending angle for the material bending line B4k of the bending material 5.

[0052] In this way, the bending process at the material bending lines B4k is performed in descending order of k, and Fig. 10 shows the abutting state in the bending process at the last material bending line B401 of side portion AR4 where k = 1. Fig. 10 is a third diagram for explaining the abutting state of the bending material 5 in the bending method of Example 1.

[0053] The gauge position acquisition unit 163 acquires the gauge position information J2 stored in the storage unit 162 when bending the material bending line B401. The gauge position information J2 includes, for example, the distance DLb, the distance Db, and the distance Lb shown in Fig. 10. These are pieces of information that determine the setting state of the backgauge device 2 when bending the bending workpiece 5 along the workpiece bending line B401.

[0054] Distance DLb is the distance in the front-to-rear direction from the left abutment surface 25La to the bending line BL in a top view. Distance Db is the distance in the front-to-rear direction between the left abutment surface 25La and the right abutment surface 25Ra in a top view. Distance Lb is the distance in the left-to-right direction in a top view between the abutment point P57 and the abutment point P23t when the abutment piece 57 of the bending workpiece 5 abuts against the left abutment surface 25La at the abutment point P57 and the connection point P23 abuts against the right abutment surface 25Ra at the abutment point P23t. 10 shows a case where the side edge 572 of the abutting piece 57 of the bending material 5 is formed parallel to the material bending line B401. In this case, the side edge 572 and the left abutting surface 25La abut in line contact rather than point contact when viewed from above, which is a plan view. The abutting point P57 indicates the end point on the tip side of the range of line contact.

[0055] The distances DLb, Db, and Lb are set so that when the connection point P23 of the bending material 5 is abutted against the right abutment surface 25Ra and the abutment tip 571 of the abutment piece 57 in the bending material 5 is abutted against the left abutment surface 25La, the material bending line B401 of the bending material 5 coincides with the bending line BL of the press brake 1.

[0056] As a result, when a worker or the like butts the butt piece 57 of the bending material 5 and the connection point P23, which is the convex tip of the basic part 50, against the left butt surface 25La and the right butt surface 25Ra, which are different butt surfaces, the material bending line B401 will coincide with the bending line BL of the press brake 1, and the bending material 5 will be set in an butted state.

[0057] Then, when the worker commands the bending operation using a foot switch or the like while the bending material 5 is in the butted state, the CPU 161 operates the lifting drive system (not shown) based on the bending information J1 and the bending program JP to lower the upper table 14 and perform bending at a predetermined bending angle with respect to the material bending line B401 of the bending material 5.

[0058] The bending process of the material bending lines B401 to 411 may be performed by abutting the abutment piece 58 and the connection point P56 of the base portion 50 against the right abutment surface 25Ra and the left abutment surface 25La, respectively, as shown in Fig. 11. Fig. 11 is a diagram for explaining another mode of abutting shown in Fig. 10. In this case, the positions of the left abutment surface 25La and the right abutment surface 25Ra of the backgage device 2 are determined by the distances Db1, DLb1, and Lb1 corresponding to the distances Db, DLb, and Lb, respectively.

[0059] As described above, in the bending method of Example 1, the bending material 5 is provided with a basic portion 50 and a butting piece portion 50h, and the positions of the butting surfaces 25La and 25Ra, which are a pair of butting surfaces that are the butting surface 25a (see Figure 2) of the backgauge device 2, are configured to be independently determinable by moving them in the front-to-back and left-to-right directions. The positions of the abutment surfaces 25La and 25Ra are then linked to the position of the material bending line to bend the bending material 5 next, and are positioned at the respective preset positions. Then, the base part 50 is abutted against one of the positioned abutment surfaces 25La and 25Ra, and the abutment piece part 50h is abutted against the other, creating an abutment set state, and bending is performed in this abutment set state. Furthermore, the bending is performed along each of the set material bending lines to form a curved surface. Then, at the final stage after the bending process is completed, the abutting piece 50h is cut off to obtain the bent product 5A.

[0060] This allows the abutting piece 50h of the bending material 5 to be made smaller. As a result, less material is needed to obtain the bent product 5A, and the cost of the bent product 5A is kept down. In addition, the distance in the left-right direction between the two abutting positions (for example, the distance La in FIG. 8) can be increased, which reduces the angle error in the bending position and enables highly accurate bending.

[0061] Furthermore, by moving the abutment surfaces 25La and 25Ra of the backgauge device 2 in parallel in the front-rear direction, the position of the material bending line can be adjusted in the front-rear direction. This allows the left-right position of the bending process on the lower table 12 of the press brake 1 to be set approximately in the center. Therefore, corrections that were previously made as needed depending on the left-right processing position relative to the table are now simple and easy. In some cases, corrections are not even necessary.

[0062] The position where the abutting piece 50h is formed on the base portion 50 is not limited to the side edge portions 52, 56 as in the bending material 5. It can be freely set according to the shape of the bent product 5A.

[0063] Example 2 12, 13A, 13B, and 14, a bent product 6A, the bent material 6 of Example 2 for obtaining the bent product 6A, and modified examples of the bent material 6 will be described. That is, Fig. 12 is a perspective view showing a bent product 6A bent by the bending method of Example 2. Fig. 13A is a plan view showing a bending workpiece 6 from which the bent product 6A is obtained by the bending method of Example 2. Fig. 13B is a plan view showing a bending workpiece 7, which is a modified example of the bending workpiece 6. Fig. 14 is a view for explaining the abutting mode of the bending workpiece 6 in the bending method of Example 2.

[0064] As shown in FIG. 12, the bent product 6A is a substantially hood-shaped semi-cylindrical body with a longer distance between both ends than the bent product 5A. The bent product 6A has curved edge 61A, side edge 62A, 66A, and straight edge 63A (not shown), 64A, 65A that correspond to curved edge 51A, side edge 52A, 56A, and straight edge 53A to 55A in the bent product 5A. The bent product 6A has side portions AR1A to AR5A, similar to the bent product 5A.

[0065] 13A, the bending material 6 for obtaining the bent product 6A has a basic portion 60 that will become the bent product 6A, and a butting piece portion 60h formed on a straight edge portion 64 that faces the curved edge portion 61 of the basic portion 60. In this example, the butting piece portion 60h is a pair of butting pieces 67, 68 formed near both ends of the straight edge portion 64. The butting pieces 67, 68 have the same shape, extend outward with a narrow width in a direction perpendicular to the straight edge portion 64, and have arc-shaped tip portions.

[0066] As shown in FIG. 13B, a bending material 7, which is a modified example of the bending material 6, has an abutment piece 70h instead of the abutment piece 60h of the bending material 6. The abutting piece portion 70h has abutting pieces 77, 78 corresponding to the abutting pieces 67, 68 of the bending material 6, and a connecting portion 79 connecting the base sides of the abutting pieces 77 and 78. In this way, it is the arc-shaped portion at the tip of the abutment piece that abuts against the abutment surfaces 25La, 25Ra of the backgauge device 2, so other portions can be deformed into any shape as long as they do not interfere with other components during bending.

[0067] Similar to the bending material 5, the bending material 6 is bent by setting a plurality of material bending lines on the side portions AR2 and AR4 to form a desired curved surface. To position the bending material 6 during the bending process, the abutment pieces 67 and 68 are abutted against both the abutment surfaces 25La and 25Ra of the backgauge device 2 from the front side to the rear side, as shown in FIG. As in Example 1, the basic part 50 is abutted against one of the abutment surfaces 25La, 25Ra of the backgauge device 2 and the abutment piece is abutted against the other, but as in Example 2, the bending material 6 may be positioned by abutting the abutment pieces 67, 68 against both the abutment surfaces 25La, 25Ra of the backgauge device 2.

[0068] Example 3 15, 16A, 16B, and 17, a bent product 8A, a bending workpiece 8 of Example 3 for obtaining the bent product 8A, and modified examples of the bending workpiece 8 will be described. FIG. 15 is a perspective view showing a bent product 8A bent by the bending method of Example 3. FIG. 16A is a plan view showing a bending workpiece 8 for obtaining the bent product 8A by the bending method of Example 3. FIG. 16B is a plan view showing a bending workpiece 9, which is a modified example of the bending workpiece 8. FIG. 14 is a diagram for explaining the abutting mode of the bending workpiece 8 in the bending method of Example 3.

[0069] As shown in FIG. 15, the bent product 8A is a semi-cylindrical, generally hood-shaped body with a shorter distance between both ends than the bent product 5A. The bent product 8A has a curved edge portion 81A, side edges 82A and 86A, and straight edges 83A (not shown), 84A, and 85A that correspond to the curved edge portion 51A, side edge portions 52A and 56A, and straight edge portions 53A to 55A of the bent product 5A. The bent product 8A has side portions AR1 to AR5, similar to the bent product 5A.

[0070] 16A, the bending material 8 for obtaining the bent product 8A has a basic portion 80 that will become the bent product 8A, and a butting piece 80h formed on a straight edge portion 84 that faces the curved edge portion 81 of the basic portion 80. In this example, the butting piece 80h is a pair of butting pieces 87, 88 formed near both ends of the straight edge portion 84. The butting pieces 87, 88 are formed in different shapes. The abutment piece 87 has a narrow width and extends outward perpendicular to the straight edge 84, and is bent at a right angle toward the straight edge 83 to form a generally L-shape, with its tip formed in an arc shape. The tip of the abutment piece 87 extends beyond an imaginary line that is an extension of the straight edge 83 and is located outside the imaginary line. The abutment piece 88 extends outward in a direction perpendicular to the straight edge portion 84 with a narrow width, and has an arc-shaped tip.

[0071] As shown in FIG. 16B, a bending material 9, which is a modified example of the bending material 8, has an abutment piece 90h instead of the abutment piece 80h of the bending material 8. The abutment piece portion 90h has abutment pieces 97, 98 that correspond to the abutment pieces 87, 88 of the bending material 8, and a connecting portion 99 that connects the base sides of the abutment pieces 97 and 98. Because it is the arc-shaped portions at the tips of the abutment pieces 87 and 88 that abut against the left abutment surface 25La and the right abutment surface 25Ra of the backgage device 2, the other portions can be deformed into any shape as long as they do not interfere with other members during the bending process.

[0072] Similar to the bending material 5, the bending material 8 is formed into a desired curved surface by setting a plurality of material bending lines on the side portions AR2 and AR4 and bending the bending material 8. To position the bending material 8 during the bending process, the abutment pieces 87 and 88 are abutted against both the left abutment surface 25La and the right abutment surface 25Ra of the backgauge device 2 from the front to the rear, as shown in FIG. The bending material 9 is also formed so that the abutting pieces abut against both the abutting surfaces 25La and 25Ra of the backgauge device 2 to position the bending material 9.

[0073] The bending methods of Examples 2 and 3 also suppress an increase in the cost of the bent products 5A and 8A, similar to Example 1. Furthermore, highly accurate bending can be performed. Furthermore, the left-right position of the bending process on the lower table 12 of the press brake 1 can be set approximately in the center. Therefore, corrections that have conventionally been made as needed depending on the left-right processing position relative to the table can be simplified and made easy. In some cases, corrections are not even necessary.

[0074] The embodiments of the present invention are not limited to the above-described configurations, and modifications may be made without departing from the spirit of the present invention. The shape of the bent product is not limited to the shapes of the bent products 5A, 6A, and 8A described above. That is, the shape of the bending material is not limited to the bending materials 5 to 9 described above, and the shape and number of the abutting pieces that make up the abutting piece portion 50h are not limited. The abutting piece may be provided with, for example, a plurality of arc-shaped extension portions that can abut against the abutting surface of the backgauge device 2.

[0075] For example, the abutment apexes 571, 581 of the abutment pieces 57, 58 in the bending material 5 are not limited to being arc-shaped, but may be arc-shaped or pointed. From the viewpoints of ease of formation of the abutment pieces 57, 58 by laser processing or press processing and prevention of deformation of the abutment apexes 571, 581 due to abutment, an arc-shaped shape is preferable to a pointed shape. In addition, an arc-shaped shape is preferable because it makes it easier to calculate the abutment position with the abutment surfaces 27La, 27Ra. The same applies to the other bending materials 6 to 9. [Explanation of symbols]

[0076] 1. Press brake 11 Side panel 12 Lower table 13 Die 14 Upper table 15 punch 16 Control device 161 Central Processing Unit (CPU) 162 Storage section 163 Gauge position acquisition unit 164 Gauge drive unit 165 Output section 17 Input Devices 18 Output Devices 2 Backgauge device 2KG gauge drive group 21 Support beam 21LK 1st direction left drive unit 21RK First direction right drive unit 22L left gauge section 22R Right gauge section 23L left gauge base 23LK Second direction left drive unit 23R Right Gauge Base 23RK Second direction right drive unit 24L left slider 24R Right Slider 25a Abutment surface 25L Left stop 25La Left butt surface 25R right end 25Ra Right abutment surface 5,6,7,8,9 Bending material 5A, 6A, 8A bending products 50,60,80 Basic part 50h, 60h, 70h, 80h, 90h Stopper 505 Development Materials 51,51A,61A,61,81A,81,91 Curved edge 52,56,52A,56A,62A,66A,82A,86A,Side edge 53~55, 53A~55A, 63A~65A, 83A~85A straight edge 57,58,67,68,77,78,87,88,97,98 Stopper 57S,58S slit 571,581 Abutment top 572,573,582,583 side part 79,99 Connecting part AR1A~AR5A, AR1~AR5 side BL fold line B201~B211, B401~B411, B4k Material bending line Da,DLa,La,Dk,DLk,Lk,Db,DLb,Lb,Db1,DLb1,Lb1 Distance J1 Bending Information J2 Gauge Position Information JP bending program LN1~LN4 border P12A,P61A corner P23, P34, P34A, P45, P45A, P56, Connection points P341, P342, P451, P452 connection points P51A position P57,P23t Stop point θ angle

Claims

1. a press brake including a first abutting section and a second abutting section, each having a first abutting surface and a second abutting surface as abutting surfaces, the first abutting section and the second abutting section being independently movable in a direction perpendicular to a bending line of a bending process and movable along the bending line so as to approach and separate from each other; A bending material to be formed into a bent product having a curved surface by bending is shaped to have a base portion which is a portion to be formed into the bent product and a butting piece portion extending outward from the base portion, A bending method for forming the curved surface by performing bending processing a predetermined number of times while positioning the material bending line of the bending processing to be performed on the bent material so that it coincides with the bending line, with the first abutment portion and the second abutment portion abutting the tip portion of the abutment piece portion against the first abutment surface in point contact and the base portion abutting the second abutment surface in point contact, and shifting the position of the material bending line for each bending processing.

2. 2. The bending method according to claim 1, wherein the bent product is obtained by cutting off the abutment piece after the bending process for forming the curved surface is completed.

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