Press brake, bending method, and bending program

Abstract

A press brake, a bending method, and a bending program capable of accurately performing additional bending on areas of a workpiece that require it after bending. [Solution] The system comprises a lower table on which a lower die is mounted, and an upper table on which an upper die is mounted, configured to be movable relative to the lower table, and configured to allow adjustment of its inclination in the vertical direction. The system is configured to perform a basic bending process on a workpiece inserted between the upper die and the lower die, bending it toward a preset bending angle, and an additional bending process on a workpiece after the standard bending process has been performed, in which additional bending is performed on areas where the bending angle is insufficient. The additional bending process is performed by raising one end of the upper table while lowering the other end.

Description

Technical Field

[0006] , , , , ,

[0001] The present invention relates to a press brake, a bending method, and a bending program.

Background Art

[0002] Conventionally, a bending machine is known that inserts a plate-shaped workpiece of a predetermined length between an upper table having an upper die and a lower table having a lower die, and presses the workpiece between the upper die and the lower die to perform bending of the workpiece (for example, Patent Document 1 and Patent Document 2, etc.).

[0003] Here, during the bending of the workpiece, due to wear of the upper die or the lower die, unevenness of the workpiece to be processed, etc., the bending angle of the whole or a part of the workpiece after bending may not reach the target angle set in advance.

[0004] Regarding such a case, in the plate bending machine described in Patent Document 1, when there is a portion where the bending angle is locally insufficient in the workpiece after bending, the ram (upper table) is inclined toward the portion where the bending angle is insufficient, so that additional local bending can be performed.

[0005] Further, in the bending machine described in Patent Document 2, instead of pressing all of the predetermined bending positions (hereinafter, bending lines) set on the workpiece at one time during bending, the upper table is inclined by a lifting mechanism in advance and then the upper table is lowered to press a part of the bending line of the workpiece. By performing a so-called partial bending a plurality of times along the bending line, the processing accuracy of the workpiece is improved.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

[0007] However, in conventional press brakes, including the plate bending machine described in Patent Document 1, which are configured to allow for retrospective correction of the bending angle of the workpiece, as shown in Figure 10, one end of the upper table (the left side in the example shown in Figure 10) is fixed as the center of rotation, and the other end (the right side in the example shown in Figure 10) is lowered to tilt the upper table. However, because one end of the upper table is used as the center of rotation, the entire upper table becomes tilted, resulting in the problem that additional bending is performed on the workpiece after bending, even in areas where angle correction is not originally necessary.

[0008] Furthermore, as shown in Patent Document 2, in a method that performs partial bending along the bending line of the workpiece multiple times, a series of operations including raising the upper table, changing the tilt of the upper table, and lowering the upper table are required each time partial bending is performed, so there is room for improvement in terms of improving work efficiency.

[0009] One aspect of the present invention is a press brake, a bending method, and a bending program that can accurately perform additional bending on a workpiece after bending, specifically at locations where additional bending is required. [Means for solving the problem]

[0010] A press brake according to one aspect of the present invention comprises a lower table on which a lower die is mounted, and an upper table on which an upper die is mounted, configured to be movable relative to the lower table, and configured to be adjustable in the vertical direction. The press brake is configured to perform a basic bending process on a workpiece inserted between the upper die and the lower die, bending it toward a preset bending angle, and an additional bending process on a workpiece after the standard bending process has been performed, in which additional bending is performed on areas where the bending angle is insufficient. The additional bending process is performed by raising one end of the upper table while lowering the other end.

[0011] Furthermore, a bending method according to one aspect of the present invention is a bending method for processing a workpiece using a press brake comprising a lower table on which a lower die is mounted, and an upper table on which an upper die is mounted, configured to be movable relative to the lower table and configured to be adjustable in the vertical direction, the bending method includes a basic bending step of bending a workpiece inserted between the upper die and the lower die toward a preset bending angle, and an additional bending step of performing additional bending on the workpiece after the basic bending step has been performed on a portion where the bending angle is insufficient, wherein the additional bending step is performed by raising one end of the upper table while lowering the other end.

[0012] Furthermore, a bending program according to one aspect of the present invention is a bending program for processing a workpiece using a press brake, comprising a lower table on which a lower die is mounted, an upper table on which an upper die is mounted, configured to be movable relative to the lower table and configured to be adjustable in the vertical direction, and a control unit for controlling the operation of the upper table. The program is configured to cause the control unit to perform a basic bending process on a workpiece inserted between the upper die and the lower die, bending it toward a preset bending angle, and an additional bending process on a workpiece after the basic bending process has been performed, in which additional bending is performed on any part where the bending angle is insufficient. The additional bending process is performed by raising one end of the upper table while lowering the other end. [Effects of the Invention]

[0013] According to one aspect of the present invention, a press brake, a bending method, and a bending program can accurately perform additional bending on a workpiece after bending, at locations where additional bending is required. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram showing a press brake according to this embodiment. [Figure 2] Figure 2 is a schematic diagram showing the control unit according to this embodiment. [Figure 3] Figure 3 is a functional block diagram showing the control unit according to this embodiment. [Figure 4] Figure 4 is a schematic diagram showing an example where an operator specifies the rotation center of the upper table via the rotation center specification unit. [Figure 5] Figure 5(a) is a schematic diagram showing an example of an angle detection position by an angle detection sensor, and Figure 5(b) is a schematic diagram showing an example of the control unit calculating the rotation center. [Figure 6] Figure 6 is a schematic diagram showing an example of the operation of the upper table during the execution of the basic bending process according to this embodiment. [Figure 7]FIG. 7 is a schematic diagram showing an operation example of the upper table during execution of the correction bending process according to the present embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of the bending method according to the present embodiment. [Figure 9] FIG. 9 is a flowchart showing an example of the bending method according to the present embodiment. [Figure 10] FIG. 10 is a schematic diagram showing the inclined state of the upper table in a conventional press brake.

Mode for Carrying Out the Invention

[0015] Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. Note that the following embodiments do not limit the invention according to each claim, and not all combinations of the features described in the embodiments are essential for the solution means of the invention. Further, in the present embodiment, there are cases where the scales and dimensions of each component are exaggeratedly shown, and cases where some components are omitted.

[0016] [Overall Configuration of Press Brake According to Present Embodiment] FIG. 1 is a schematic diagram showing a press brake according to the present embodiment. First, referring to FIG. 1, the press brake 1 according to the embodiment of the present invention will be outlined. The press brake 1 according to the present embodiment is schematically configured as shown in FIG. 1, including a lower table 20 on which a lower die D is mounted, and an upper table 10 on which an upper die P is mounted and which is configured to be relatively movable with respect to the lower table 20 and to be adjustable in inclination in the vertical direction. The press brake 1 is configured to perform a basic bending process for bending a work W inserted between the upper die P and the lower die D toward a preset bending angle, and an additional bending process for performing additional bending on a portion of the work W where the bending angle is insufficient after the basic bending process.

[0017] Specifically, the press brake 1 according to the present embodiment includes an upper table 10 and a lower table 20 that are arranged in vertical alignment at the center of the front surface such that one surface in the front-rear direction, for example, the outer plate surfaces, face the front surface respectively.

[0018] In this specification, the "vertical direction" refers to the vertical direction (Z direction in FIG. 1) in the installation state of the press brake 1, and the "left-right direction" refers to the extending direction of the upper table 10 and the lower table 20 (X direction in FIG. 1) in the installation state of the press brake 1. Further, the "front-rear direction" refers to the direction orthogonal to both the vertical direction and the left-right direction (Y direction in FIG. 1). However, the vertical direction, left-right direction, and front-rear direction in this specification are merely formal directions defined for convenience of explanation and are not necessarily the same as the vertical direction, etc. in the actual usage situation.

[0019] The upper table 10 is made of a plate-like member such as metal, etc., and has a plurality of upper die holders (not shown) that hold an upper die P such as a punch at the lower end. The lower table 20 is made of a plate-like member such as metal similar to the upper table 10, and has a lower die holder (not shown) that holds a lower die D such as a die at the upper end.

[0020] Also, as shown in FIG. 1, the press brake 1 according to the present embodiment is configured to reciprocate the upper table 10 along the vertical direction with respect to the lower table 20, and is provided with a drive mechanism 30 configured to be able to adjust the inclination angle of the upper table 10 in the vertical direction, and an angle detection sensor 40 capable of detecting the bending angle of the work W on which basic bending has been performed. Further, the press brake 1 is provided with a rotation center specifying unit 50 configured to be able to specify a rotation center RP described later.

[0021] The drive mechanism 30 is, for example, a hydraulic cylinder that serves as the drive source for the upper table 10, and is attached to both ends in the left-right direction of the support section (not shown) that supports the upper table 10 and the lower table 20. Here, each drive mechanism 30 is configured to reciprocate (move up and down) relative to the lower table 20 in the vertical direction by height control by the movement control section 142 of the drive control section 140, which will be described later. With this configuration, the upper die P attached to the upper die holder (not shown) of the upper table 10 and the lower die D attached to the lower die holder (not shown) of the lower table 20 are configured to move relative to each other.

[0022] Furthermore, each drive mechanism 30 is controlled by the tilt control unit 146 of the drive control unit 140, which will be described later, and is configured to tilt the entire upper table 10 by rotating it vertically around the rotation center RP, which will be described later. Specifically, as will be described later, when each drive mechanism 30 receives an operation control signal transmitted from the tilt control unit 146 of the drive control unit 140 after the rotation center RP has been specified or set, it is configured to tilt the entire upper table 10 downwards by raising one end of the upper table 10 with one drive mechanism 30 and lowering the other end of the upper table 10 with the other drive mechanism 30 based on the position of the rotation center RP.

[0023] Thus, the drive mechanism 30 is configured to tilt the upper table 10, making it possible to apply additional bending to areas of the workpiece W after the basic bending process described later where the bending angle is locally insufficient. Furthermore, since the drive mechanism 30 is configured to raise one end of the upper table 10 and lower the other end around the rotation center RP, it is possible to appropriately apply pressure only to the areas of the workpiece W after bending that require additional bending or their surroundings, compared to a conventional press brake configured to lower only one end of the upper table as shown in Figure 10.

[0024] In the above description, the drive mechanism 30 was described as being attached to both ends of the upper table 10 in the left-right direction, but the invention is not limited to this, and for example, the drive mechanism 30 may be configured to be attached near the center of the upper table 10. Also, in this embodiment, the drive mechanism 30 is fixed to the upper table 10 so as not to move, but the invention is not limited to this, and for example, the drive mechanism 30 may be configured to be movable along the left-right direction of the upper table 10 by various means of movement (not shown). Even with such a configuration, it is possible to perform the above-described adjustment operation of the tilt position of the upper table 10.

[0025] As shown in Figure 1, the angle detection sensor 40 is provided, for example, on the front surface of the lower table 20 and mounted on an angle detection sensor moving part (not shown) provided on the front surface of the lower table. The angle detection sensor moving part (not shown) is a moving mechanism configured to move freely along the left-right direction of the lower table, and is configured to move freely in the left-right direction with the angle detection sensor 40 attached. As a result, the angle detection sensor 40 is configured to move freely in the left-right direction.

[0026] In the above description, the angle detection sensor 40 was described as being configured to be movable in the left-right direction, but it is not limited to this, and the angle detection sensor 40 only needs to be configured to be movable in at least the left-right direction. Furthermore, since various known configurations can be adopted for the angle detection sensor 40 and the angle detection sensor movement unit, a detailed explanation thereof is omitted.

[0027] The rotation center designation unit 50 is generally configured to allow the designation of the rotation center RP of the upper table 10. Specifically, as shown in Figure 1, the rotation center designation unit 50 is provided on the front surface of the upper table 10 and extends from one end to the other in the left-right direction of the upper table 10. The rotation center designation unit 50 also has a display as a display unit, and the display is configured to show, for example, a screen for designating the rotation center RP, which is created based on an image captured by a camera (not shown) provided on the rear surface of the upper table 10, as shown in Figure 4. Furthermore, the rotation center designation unit 50 according to this embodiment is composed of a touch panel that functions as an input unit, so that the operator can perform operations such as designating the rotation center RP by, for example, touching any part of the image displayed on the display unit.

[0028] Furthermore, the rotation center designation unit 50 according to this embodiment is configured to transmit the position of the rotation center RP, which is specified via the rotation center RP designation screen described above, to the tilt control unit 146 of the control unit 100, which will be described later. With this configuration, the operator does not need to move to the location where the control unit 100 is installed and then input the rotation center RP via the control unit 100, thereby improving efficiency when designating the rotation center RP. In addition, since the rotation center RP can be designated via the designation screen displayed on the display unit described above, the rotation center RP can also be designated intuitively.

[0029] In the above description, the rotation center designation section 50 was described as being provided on the front surface of the upper table 10 and extending from one end to the other end in the left-right direction. However, it is not limited to this, and for example, the rotation center designation section 50 may be provided on the lower table 20. Also, the rotation center designation section 50 does not have to be provided from one end to the other end in the left-right direction. Furthermore, in this embodiment, the rotation center designation section 50 is provided integrally with the press brake 1, but it is not limited to this, and the rotation center designation section 50 may be a separate component that is retrofitted to the press brake 1, or multiple rotation center designation sections 50 may be provided.

[0030] Furthermore, in the above description, the rotation center designation unit 50 was described as being composed of a touch panel with input functionality, and configured so that the operator can designate the rotation center RP by touching any location. However, it is not limited to this configuration. For example, the rotation center RP may be designed so that the operator can designate the rotation center RP by clicking any location in the image displayed on the display unit of the rotation center designation unit 50 via an input medium such as a mouse.

[0031] The press brake 1, having the configuration described above, is configured to perform a basic bending process on a workpiece W inserted between the upper die P and the lower die D, bending it towards a preset bending angle, and an additional bending process on the workpiece W after the basic bending has been performed, performing additional bending on any areas where the bending angle is insufficient. The configuration of the press brake 1 is not limited to the configuration described above, and various known configurations can be adopted, such as a back gauge (not shown) for positioning the workpiece W inserted between the upper die P and the lower die D in the depth direction, and a position detection sensor (not shown) capable of detecting the relative movement position of the upper die P with respect to the lower die D when the upper table 10 is moved by the drive mechanism 30.

[0032] [Configuration of the control unit] Furthermore, as shown in Figures 1 to 3, the press brake 1 according to this embodiment includes a control unit 100 that controls the operation of the upper table 10. Specifically, the control unit 100 is configured to perform operation control of the drive mechanism 30 and operation control of the angle detection sensor 40.

[0033] Figure 2 is a schematic diagram showing the control unit according to this embodiment. As shown in Figure 2, the control unit 100 includes an input unit 110 and a display unit 120. In this embodiment, the control unit 100 is composed of a general-purpose NC (Numerical Control) device or a personal computer, and is connected to the press brake 1 by various known configurations. Furthermore, if the rotation center designation unit 50 is configured as a separate component that can be attached to the press brake 1, it is preferable that the control unit 100 is also configured to be connectable to the rotation center designation unit 50.

[0034] The input unit 110 is composed of input devices such as a keyboard, mouse, push-button switch, tact switch, and key lock switch. By operating the input unit 110, in addition to the information input functions normally required in bending the workpiece W with the press brake 1, operations such as specifying the position of the rotation center RP of the upper table 10 can be performed.

[0035] The display unit 120 has a display as a display device, and in addition to the screen display functions normally required in the press brake 1, it is configured to display, for example, a screen showing the tilt angle of the upper table 10. Preferably, the screen displayed on the display unit 120 is configured to display information such as an enlarged view of the vicinity of the location designated or set as the rotation center RP of the upper table 10, or a reference view of the upper table 10 when rotated around the rotation center RP, as shown in Figure 2. By configuring the display unit 120 to display various information in this way, it becomes possible to enable the operator to perform tasks such as checking and changing the tilt angle of the upper table 10 more efficiently.

[0036] Furthermore, the display unit 120 may be configured as a touch panel having the functions of the input unit 110. If the display unit 120 is configured as a touch panel, the operator can perform operations to specify the rotation center RP, such as changing the position of the rotation center RP by moving the rotation center RP displayed on the display unit 120 with a finger or the like.

[0037] Furthermore, the configuration of the input unit 110 and the display unit 120 is not limited to the configuration described above. Any configuration that has equivalent functionality to the input unit 110 and the display unit 120 (for example, a display means or input means that can be used remotely) is also acceptable.

[0038] Furthermore, the press brake 1 according to this embodiment includes a tilt operation unit 70 that allows the operator to tilt the upper table 10. As shown in Figure 2, the tilt operation unit 70 according to this embodiment is configured as a rotatable handle provided on the front of the control unit 100, and when the operator rotates the tilt operation unit 70, it sends a signal to the drive mechanism 30 to adjust the tilt of the upper table 10, thereby enabling adjustment of the tilt direction of the upper table 10. Specifically, when the tilt operation unit 70 is rotated, it sends a signal to the drive control unit 140 (described later) to adjust the tilt of the upper table 10, and then transmits this signal to the drive mechanism 30 via the drive control unit 140, thereby enabling adjustment of the tilt direction of the upper table 10. In other words, the tilt operation unit 70 is configured to indirectly transmit a control signal to the drive mechanism 30.

[0039] In this embodiment, it is preferable that the tilt operation unit 70 is configured such that, for example, when the operator rotates the tilt operation unit 70 to the left, the left end of the upper table 10 descends and the right end rises, so that the rotation direction of the tilt operation unit 70 and the rotation direction of the upper table 10 are linked. This configuration has the advantage that the operator can intuitively change the tilt angle of the upper table 10.

[0040] In this embodiment, the tilt operation unit 70 is described as being located on the front of the control unit 100 and integrated with the control unit 100. However, it is not limited to this configuration, and the tilt operation unit 70 may be provided separately from the control unit 100, for example, by being located on the upper table 10 or the lower table 20. Furthermore, in this embodiment, the tilt operation unit 70 is described as being configured to indirectly transmit a signal to the drive mechanism 30 indicating that the tilt of the upper table 10 should be adjusted. However, it is not limited to this configuration, and the tilt operation unit 70 may be configured to directly send a control signal to the drive mechanism 30.

[0041] Figure 3 is a functional block diagram showing the control unit according to this embodiment. Furthermore, as shown in Figure 3, the control unit 100 includes an angle detection sensor control unit 130 capable of controlling the angle detection sensor 40, a drive control unit 140 capable of controlling the operation of the upper table 10 by the drive mechanism 30, and a storage unit 150.

[0042] The angle detection sensor control unit 130 is configured to perform control such as controlling the movement of the angle detection sensor 40 by the angle detection sensor moving unit (complete unit) described above, and setting the angle detection position of the workpiece W during bending by the angle detection sensor 40.

[0043] Specifically, the angle detection sensor control unit 130 controls the angle detection sensor movement unit (not shown) to move the angle detection sensor 40 toward a predetermined angle detection position on the workpiece W after the execution of the basic bending process and after the execution of the additional bending process. The angle detection sensor control unit 130 also transmits the bending angle of the workpiece W detected at the angle detection position to the calculation unit 144 of the drive control unit 140.

[0044] The angle detection sensor control unit 130 is configured to allow arbitrary setting of the angle detection position of the workpiece W. Specifically, the angle detection position of the workpiece W set by the angle detection sensor control unit 130 is configured to allow setting of any position in the longitudinal direction of the workpiece W after the basic bending process and the additional bending process described above. Preferably, two or more positions are set in the longitudinal direction of the workpiece W after the basic bending process and the additional bending process. More specifically, it is more preferable that the angle detection positions of the workpiece W set by the angle detection sensor control unit 130 be two positions: one end in the longitudinal direction of the workpiece W after the basic bending process and the additional bending process, and the center in the longitudinal direction. It is even more preferable that there are three positions: both ends in the longitudinal direction and the center in the longitudinal direction.

[0045] In this way, by setting two or more angle detection positions by the angle detection sensor 40 in the longitudinal direction of the workpiece W, it becomes possible to perform the calculation of the rotation center RP by the calculation unit 144, which will be described later. Furthermore, if the angle detection positions by the angle detection sensor 40 are set to three locations: both ends in the longitudinal direction and the center in the longitudinal direction, it is possible to further improve the accuracy of the calculation of the rotation center RP by the calculation unit 144.

[0046] However, the angle detection position of the workpiece W described above is merely an example, and it is possible to set it to any position that takes into account the shape and dimensions of the workpiece W to be processed.

[0047] As shown in Figure 3, the drive control unit 140 includes a movement control unit 142 capable of controlling the reciprocating motion of the upper table 10 along the vertical direction, a calculation unit 144 capable of calculating the rotation center RP based on information regarding the bending angle of the workpiece W transmitted from the angle detection sensor control unit 130 described above, and a tilt control unit 146 capable of tilting the upper table 10 around the rotation center RP calculated by the calculation unit 144.

[0048] The movement control unit 142 is configured to control the vertical movement of the upper table 10 by transmitting a signal to the drive mechanism 30 to raise or lower the upper table 10. Specifically, when performing a basic bending process on a workpiece W inserted between the upper die P and the lower die D, the movement control unit 142 transmits a signal to the drive mechanism 30 to lower the upper table 10 to a predetermined position, thereby applying pressure to the workpiece W inserted between the upper die P and the lower die D along the bending line F and controlling the workpiece W to bend to a predetermined angle.

[0049] In this embodiment of the press brake 1, the movement control unit 142 is configured to control the drive mechanism 30 so as to move the upper table 10 slightly upward when the bending angle of the workpiece W is detected by the angle detection sensor 40 described above. With this configuration, the angle detection sensor 40 can detect a bending angle that takes into account the rebound (so-called springback) of the workpiece W when the pressure on the workpiece W is released. Therefore, it is possible to more accurately detect areas in the workpiece W after the basic bending process and after the additional bending process where the bending angle is insufficient.

[0050] The calculation unit 144 is configured to calculate the rotation center RP of the upper table 10 based on information regarding the bending angle of the workpiece W after the basic bending process, which is detected by the angle detection sensor 40. The method by which the calculation unit 144 calculates the rotation center RP will be described in detail later.

[0051] The tilt control unit 146 is configured to raise one end of the upper table 10 while lowering the other end, with respect to the rotation center RP calculated by the calculation unit 144, when an additional bending process is performed. Specifically, the tilt control unit 146 is configured to determine whether the location designated as the rotation center RP is located to the right or left of the center of the upper table 10 in the left-right direction. For example, if it is determined that the position of the rotation center RP is located to the right of the center of the upper table 10 in the left-right direction, the tilt control unit 146 is configured to control the drive mechanism 30 so that the right end of the upper table 10 is lowered and the left end is raised.

[0052] Furthermore, the tilt control unit 146 is configured to sequentially execute rotation control of the upper table 10 around the rotation centers RP when multiple rotation centers RP are specified or set. For example, the tilt control unit 146 rotates the upper table 10 around the first rotation center RP to perform additional bending processing on the workpiece W after the basic bending processing, and then rotates the upper table 10 around the second rotation center RP to perform additional bending processing on other parts of the workpiece W, and so on, repeatedly executing rotation control of the upper table 10 around all rotation centers RP.

[0053] The memory unit 150 is configured to store information normally required in bending a workpiece W using the press brake 1, such as information regarding the dimensions and positions of the upper table 10 and the lower table 20, information regarding the dimensions and shape of the workpiece W to be processed, information regarding the target bending angle of the workpiece W, and information regarding the position of the rotation center RP as described above. The memory unit 150 also includes a bending program 200, as shown in Figure 3.

[0054] The bending program 200 is a bending program that processes a workpiece W using a press brake 1 which comprises a lower table 20 on which a lower die D is mounted, an upper table 10 on which an upper die P is mounted and which is configured to be movable relative to the lower table 20 and to be adjustable in the vertical direction, and a control unit 100 that controls the operation of the upper table 10. The program is configured to cause the control unit 100 to perform a basic bending process that bends the workpiece W inserted between the upper die P and the lower die D toward a preset bending angle, and an additional bending process that performs additional bending on the workpiece W after the basic bending process has been performed on any part where the bending angle is insufficient. Furthermore, the bending program 200 according to this embodiment performs the additional bending process by raising one end of the upper table 10 while lowering the other end, with respect to the position of a specified or set rotation center RP.

[0055] [Example of specifying the center of rotation by the operator] Figure 4 is a schematic diagram showing an example of an operator specifying the rotation center via the rotation center specification unit. Figure 6 is a schematic diagram showing an example of the operation of the upper table during the execution of the basic bending process according to this embodiment. Furthermore, Figure 7 is a schematic diagram showing an example of the operation of the upper table during the execution of the additional bending process according to this embodiment. Next, with reference to Figures 4, 6, and 7, we will explain how an operator can specify the rotation center RP of the upper table 10 and the operation of the upper table 10 when performing additional bending processing around the specified rotation center RP. In the example shown in Figure 4, we will explain assuming that only one rotation center RP is set, but this is not limited to this, and multiple rotation centers RP may be set.

[0056] First, as a preliminary step to specifying the rotation center RP of the upper table 10 via the rotation center specification unit 50, a basic bending process is performed on the workpiece W by lowering the upper table 10 so that the workpiece W reaches a predetermined bending angle (see Figure 6). After the basic bending process, if it is determined that the bending angle of the workpiece W has not reached the predetermined bending angle, the operator, as shown in Figure 4, touches a predetermined location on the upper die P mounted on the upper table 10 in the image displayed on the rotation center specification unit 50 to specify the selected location as the rotation center RP. Note that the method of specifying the rotation center RP is not limited to selecting any location on the upper die P mounted on the upper table 10, as shown in Figure 4. In other cases, for example, the operator may touch a predetermined location on the workpiece W in the image displayed on the rotation center specification unit 50, thereby designating the position corresponding to the predetermined location on the workpiece W selected on the upper table 10 as the rotation center RP. In such cases, the rotation center RP can be specified in various arbitrary ways.

[0057] After the rotation center RP is specified by the rotation center designation unit 50, the operator rotates the tilt operation unit 70 to rotate the upper table 10 around the rotation center RP. In the example shown in Figure 4, the rotation center RP is set to the right of the center of the workpiece W in the left-right direction, so the operator rotates the tilt operation unit 70 to the right. As a result, the drive mechanism 30 causes the upper table 10 to move so that its right end is lowered and its left end is raised, and as shown in Figure 7, the upper table 10 as a whole is tilted to the right and downward, so that an additional bending process is performed on the end of the workpiece W that is to the right of the center in the longitudinal direction after the basic bending process.

[0058] [Example of setting the rotation center by the control unit] Figure 5(a) is a schematic diagram showing an example of an angle detection position by an angle detection sensor, and Figure 5(b) is a schematic diagram showing an example of the control unit calculating the rotation center. Next, the method for setting the rotation center RP by the control unit 100 will be described. First, in the method for setting the rotation center RP of the upper table 10 by the control unit 100, as shown in Figure 5(a), the angle detection sensor 40 detects the bending angle of a predetermined location on the workpiece W after the basic bending process. In the example shown in Figure 5(a), the bending angles of both ends and the center in the left-right direction of the bend line F of the workpiece W after the basic bending process are detected, but the system is not limited to this.

[0059] First, as a preliminary step before the control unit 100 calculates the rotation center RP of the upper table 10, the upper table 10 is lowered so that the workpiece W is at a preset bending angle, thereby performing a basic bending process on the workpiece W (see Figure 6). Subsequently, the angle detection sensor control unit 130 operates the angle detection sensor 40 to detect the bending angle at a predetermined position of the workpiece W after the basic bending process.

[0060] After the angle detection sensor 40 detects the bending angle of the workpiece W, the calculation unit 144 of the control unit 100 acquires information regarding the bending angle detected by the angle detection sensor 40 and calculates the rotation center RP based on the acquired information. Here, an example of how the calculation unit 144 calculates the rotation center RP will be explained with reference to Figure 5(b). In Figure 5(b), the vertical axis represents the magnitude of the bending angle detected at the angle detection point, and the horizontal axis represents the length of the workpiece W in the left-right direction. Furthermore, the angle detection point in Figure 5(b) corresponds to the angle detection point in Figure 5(a), and the length on the horizontal axis in Figure 5(b) corresponds to the length of the bending line F in Figure 5(a).

[0061] Furthermore, the target angle refers to the target bending angle of the workpiece W that is predetermined in the basic bending process. In other words, in Figure 5(b), if the bending angle detected at the angle detection point is located above the target angle, it means that the bending angle detected at that point has not reached the target angle. Conversely, if the bending angle detected at the angle detection point is located below the target angle, it means that the bending angle detected at that point has exceeded the target angle.

[0062] The target angle of the workpiece W set in the calculation unit 144 is calculated by comprehensively considering the target angle set in advance before the execution of the basic bending process, information on the shape and dimensions of the workpiece W to be processed, information on the length of the bending line F of the workpiece W and the position of the bending line F relative to the workpiece W, and information on the wear status of the upper die P and lower die D, as well as information on the shape of the upper die P, which are input by the input unit 110, etc. and stored in the storage unit 150.

[0063] As shown in Figure 5(b), the calculation unit 144 sets the position of the intersection point RP as the rotation center RP when there is an intersection point between a virtual straight line connecting multiple angle detection points (three points in the example shown in Figure 5(b)) and the target angle. With this configuration, it is possible to set the starting point of the region where the bending angle is insufficient in the workpiece W after bending as the rotation center RP, thereby ensuring that additional bending is performed on the region where the bending angle is insufficient in the workpiece W after bending.

[0064] In the example described above, it was assumed that there is an intersection point between a virtual line connecting multiple angle detection points and the target angle. However, there are cases where there is no intersection point between the virtual line and the target angle. In this case, since the bending angle of the workpiece W after bending is likely to be insufficient overall, the calculation unit 144 does not set the rotation center RP. That is, in this case, the rotation control of the upper table 10 by the drive control unit 140 is not performed, and the movement control unit 142 performs additional bending by controlling the drive mechanism 30 so that the vertical position (bottom dead center) of the upper table 10 is positioned lower than the bottom dead center during the basic bending process.

[0065] After the rotation center RP is set by the calculation unit 144, the tilt control unit 146 controls the drive mechanism 30 to tilt the upper table 10 with respect to the rotation center RP. In the example shown in Figure 5(b), since the rotation center RP is set to the right of the center of the workpiece W in the left-right direction, the tilt control unit 146 controls the drive mechanism 30 to lower the right end of the upper table 10 and raise the left end. As a result, as shown in Figure 7, the upper table 10 as a whole is tilted to the right and downward, so that an additional bending process is performed on the end of the workpiece W that is to the right of the center in the longitudinal direction after the basic bending process.

[0066] In the example shown in Figure 5(b), since the rotation center RP is also set to the left of the center of the workpiece W in the left-right direction, the drive control unit 140 performs continuous operation after the additional bending is performed in the example shown in Figure 7. Specifically, after the first additional bending process performed around the rotation center RP set to the right of the workpiece W, the tilt control unit 146 of the drive control unit 140 controls the drive mechanism 30 to lower the left end of the upper table 10 and raise the right end, using the rotation center RP set to the left of the workpiece W as the center. As a result, the upper table 10 as a whole tilts to the left and downward, and a second additional bending process is performed on the workpiece W. With this, all tilt changes and additional bending of the upper table 10 based on the rotation center RP have been performed, and continuous operation ends.

[0067] [Overview of the bending method according to this embodiment] Figure 8 is a flowchart showing an example of a bending process according to this embodiment. Next, an example of a bending method according to this embodiment will be described with reference to Figures 8 and 9. The bending method according to this embodiment is a bending method for processing a workpiece W using a press brake 1 which comprises a lower table 20 on which a lower die D is mounted, and an upper table 10 on which an upper die P is mounted, configured to be movable relative to the lower table 20 and configured to be adjustable in the vertical direction. The bending method includes a basic bending step in which the workpiece W inserted between the upper die P and the lower die D is bent toward a preset bending angle, and an additional bending step in which additional bending is performed on the workpiece W after the basic bending step has been performed on any part where the bending angle is insufficient. The additional bending step is performed by raising one end of the upper table 10 while lowering the other end.

[0068] In the bending method illustrated in Figure 8, the operator specifies the rotation center RP and tilts the upper table 10 by operating the tilt operation unit 70. In the bending method illustrated in Figure 9, the control unit 100 sets the rotation center RP and changes the tilt of the upper table 10 by the control unit 100. However, the method is not limited to these methods. For example, the operator may specify the rotation center RP, and then the control unit 100 may change the tilt of the upper table 10 around the specified rotation center RP. Alternatively, the control unit 100 may set the rotation center RP, and then the operator may operate the tilt operation unit 70 to change the tilt of the upper table 10 around the set rotation center RP.

[0069] Furthermore, for the sake of clarity in the following explanation, it will be assumed that the bending angle of some parts of the workpiece W after the basic bending process has not reached the predetermined bending angle. However, the explanation is not limited to this, and it is not necessary for the bending angle of all parts of the workpiece W after the basic bending process to not reach the predetermined bending angle.

[0070] First, the bending method used when an operator changes the inclination of the upper table 10 in the press brake 1 according to this embodiment will be explained with reference to Figure 8. First, the operator operates the press brake 1 and performs bending on the workpiece W to be processed toward a preset bending angle (S10 in Figure 8: basic bending process). After the basic bending process is completed, the operator checks whether the bending angle of the workpiece W, which has been bent in various arbitrary ways, has reached the preset bending angle. If the bending angle has not reached the preset bending angle (NO in S20 in Figure 8), the operator specifies the rotation center RP via the rotation center specification unit 50 (S30 in Figure 8: rotation center specification process). On the other hand, if the bending angle has reached the preset bending angle (YES in S20 in Figure 8), the bending of the workpiece W is completed (END in Figure 8).

[0071] After specifying the rotation center RP, the operator rotates the upper table 10 around the rotation center RP by operating the tilting operation unit 70 with the workpiece W inserted between the upper die P and the lower die D. As a result, one end of the upper table 10 rises and the other end falls, so that the workpiece W inserted between the upper die P and the lower die D is locally pressed (S40 in Figure 8: additional bending process).

[0072] After the additional bending of the workpiece W is performed, if there are other rotation centers RP designated by the rotation center designation unit 50 (YES in S50 in Figure 8), the upper table 10 is tilted around a rotation center RP that was not used during the previous additional bending process, and the additional bending process (S40) is performed. This process is repeated until additional bending processes have been performed around all rotation centers RP.

[0073] If, after the additional bending of the workpiece W, there is no other rotation center RP designated in the rotation center designation unit 50 (NO in S50 in Figure 8), the operator checks whether the bending angle of the workpiece W after the additional bending has reached a preset bending angle (S20 in Figure 8). If the bending angle of the workpiece W after the additional bending has not reached a preset bending angle (NO in S20 in Figure 8), the rotation center designation configuration (S30) and the additional bending process (S40) are repeatedly executed until the bending angle of the workpiece W after the additional bending reaches a preset bending angle.

[0074] On the other hand, if the bending angle of the workpiece W after the additional bending has reached a preset bending angle (YES in S20 in Figure 8), the bending of the workpiece W is terminated (END in Figure 8). Through the above steps, a series of bending methods are performed when the operator changes the tilt of the upper table 10.

[0075] Figure 9 is a flowchart showing an example of a bending process according to this embodiment. Next, the bending process in the press brake 1 according to this embodiment will be described when the control unit 100 sets the rotation center RP and controls the operation of the upper table 10. First, the drive control unit 140 of the control unit 100 reads the bending program 200 which is input from the input unit 110 etc. and stored in the memory unit 150, and controls the drive mechanism 30 to lower the upper table 10 to a predetermined position, thereby performing a basic bending process in which the workpiece W inserted between the upper die P and the lower die D is bent towards a preset bending angle (S100 in Figure 9: basic bending process).

[0076] After the basic bending process (S100 in Figure 9), the angle detection sensor control unit 130 of the control unit 100 controls the angle detection sensor 40 to detect the bending angle of a predetermined position of the workpiece W while the bent workpiece W is held between the upper die P and the lower die D (S110 in Figure 9: bending angle detection process). During the execution of the bending angle detection process, the movement control unit 142 of the drive control unit 140 controls the drive mechanism 30 to move the upper table 10 slightly upward, thereby reducing the pressure applied to the workpiece W, from the viewpoint of allowing the angle detection sensor 40 to detect a bending angle that takes into account the rebound of the bending angle when the pressure is released.

[0077] After the angle detection sensor 40 detects the bending angle (S110 in Figure 9), the calculation unit 144 of the drive control unit 140 obtains the detection result of the bending angle of the workpiece W after the basic bending process from the angle detection sensor control unit 130, and determines whether the bending angle of the workpiece W has reached a preset bending angle. If it is determined that the bending angle has not reached a preset bending angle (NO in S120 in Figure 9), it calculates the rotation center RP and sets the rotation center RP based on the calculation result (S130 in Figure 9: rotation center calculation process). The method of calculating the rotation center RP by the calculation unit 144 is the same as described in this specification and is therefore omitted here.

[0078] After the rotation center position calculation process (S130 in Figure 9), the tilt control unit 146 controls the drive mechanism 30 to rotate the upper table 10 around the rotation center RP set by the calculation unit 144. As a result, one end of the upper table 10 rises and the other end descends, so that the workpiece W inserted between the upper die P and the lower die D is locally pressed (S140 in Figure 9: additional bending process).

[0079] After the additional bending of the workpiece W is performed, if there are other rotation centers RP set in the calculation unit 144 (YES in S150 of Figure 9), the additional bending process (S150) is performed around the rotation center RP that was not used during the previous additional bending. This series of steps is repeated until the additional bending process has been performed around all rotation centers RP set in the calculation unit 144.

[0080] After the additional bending of the workpiece W is performed, if there is no other rotation center RP set in the calculation unit 144 (NO in S160 in Figure 9), the bending angle detection process is performed again (S110 in Figure 9) to detect the bending angle of the workpiece W that has undergone the additional bending process. If the bending angle of the workpiece W after the additional bending has not reached the preset bending angle (NO in S120 in Figure 9), the rotation center calculation process (S130 in Figure 9) and the additional bending process (S140 in Figure 9) described above are repeated until the bending angle of the workpiece W reaches the preset bending angle.

[0081] If the bending angle of the workpiece W after the additional bending has reached a preset bending angle (YES in S120 in Figure 9), the bending of the workpiece W is terminated (END in Figure 9). Through the above steps, the control unit 100 executes a series of bending processes.

[0082] Furthermore, when performing the bending process according to this embodiment continuously, the rotation center RP can be specified or calculated only during the first trial run (check run), and information regarding the position of the rotation center RP during the trial run can be stored in the workpiece processing program of the control unit 100. This allows for the omission of specifying or calculating the rotation center RP from the second time onward, or the rotation center RP can be specified or calculated each time.

[0083] [Advantages of the press brake, bending method, and bending program according to this embodiment] As described above, the press brake 1 according to this embodiment comprises a lower table 20 on which a lower die D is mounted, and an upper table 10 on which an upper die P is mounted, configured to be movable relative to the lower table 20, and configured to be adjustable in the vertical direction. The press brake 1 is configured to perform a basic bending process on a workpiece W inserted between the upper die P and the lower die D, bending it toward a preset bending angle, and an additional bending process on the workpiece W after the basic bending process, performing additional bending on any parts where the bending angle is insufficient. The additional bending process is performed by raising one end of the upper table 10 while lowering the other end.

[0084] Furthermore, the press brake 1 according to this embodiment, with this configuration, is capable of accurately performing additional bending processing only on the parts of the workpiece W where the bending angle is insufficient after the basic bending process, or on the area around the parts where the bending angle is insufficient, thereby improving the bending accuracy of the entire workpiece W after bending. In addition, since the additional bending process is performed by raising one end of the upper table 10 while lowering the other end when the workpiece W is inserted between the upper die P and the lower die D, it is also possible to improve the work efficiency when performing the additional bending process.

[0085] Furthermore, the press brake 1 according to this embodiment further includes a rotation center designation unit 50 that can specify the rotation center RP of the inclination of the upper table 10, and the upper table 10 is configured to be able to adjust its inclination around the rotation center designated by the rotation center designation unit 50. With this configuration, it is possible for the operator to designate any point as the rotation center of the upper table 10, so that additional bending processing can be accurately performed on parts of the workpiece W where the bending angle is insufficient after the basic bending processing has been performed.

[0086] Furthermore, the press brake 1 according to this embodiment further includes an angle detection sensor 40 capable of detecting the bending angle of a workpiece W after basic bending processing has been performed, and the angle detection sensor 40 is configured to be movable in the left-right direction of the upper table 10 and the lower table 20. With this configuration, it is possible to detect the bending angle of the workpiece W after basic bending processing more accurately.

[0087] Furthermore, the press brake 1 according to this embodiment further includes a control unit 100 that controls the operation of the upper table 10. The control unit 100 includes a calculation unit 144 that calculates the rotation center of the upper table 10 based on information regarding the bending angle of the workpiece W detected by the angle detection sensor 40, and a tilt control unit 146 that can control the tilt of the upper table 10. The tilt control unit 146 is configured to raise one end of the upper table 10 while lowering the other end, with respect to the rotation center RP calculated by the calculation unit 144, when additional bending processing is performed. With this configuration, it is possible to more accurately perform additional bending processing on areas of the workpiece W where the bending angle is insufficient after the basic bending processing. In addition, since the operator does not need to specify the rotation center RP of the upper table 10, it is possible to uniformly perform additional bending processing on multiple workpieces W, for example, and it is possible to promote the reduction of operator skill.

[0088] Furthermore, the press brake 1 according to this embodiment includes a tilting operation unit 70 that allows the operator to tilt the upper table 10. With this configuration, the operator can tilt the upper table 10 at any time they choose.

[0089] [Differentiation] Although preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the embodiments described above. Various modifications or improvements can be made to the embodiments described above.

[0090] For example, in the embodiment described above, the press brake 1 was described as having a rotation center designation unit 50 that can specify the rotation center of the inclination of the upper table 10, but it is not limited to this, and a configuration without a rotation center designation unit 50 is also possible.

[0091] Furthermore, in the embodiments described above, the press brake 1 was described as being equipped with an angle detection sensor 40 capable of detecting the bending angle of the workpiece W on which the basic bending process has been performed. However, it is not limited to this, and the press brake 1 does not need to be equipped with an angle detection sensor 40.

[0092] Furthermore, although the above-described embodiment assumed that the press brake 1 is configured to calculate the rotation center RP of the upper table 10 using the calculation unit 144, it is not limited to this configuration, and it may be configured not to calculate the rotation center RP. Also, although the above-described embodiment assumed that the tilt of the upper table 10 can be controlled by the tilt control unit 146, it is not limited to this configuration, and it is not necessary for the tilt of the upper table 10 to be controlled by the tilt control unit 146.

[0093] Furthermore, although the above-described embodiment was explained in which the press brake 1 is equipped with a tilting operation unit 70 that allows the operator to tilt the upper table, it is not limited to this, and a configuration without a tilting operation unit 70 is also possible.

[0094] It is clear from the claims that the above-mentioned modifications are included within the scope of the present invention. [Explanation of symbols]

[0095] 1: Press brake 10: Upper table 20: Lower Table 30: Drive mechanism 40: Angle detection sensor 50: Rotation center designation part 70: Tilt operation section 100: Control Unit 110: Input section 120: Display section 130: Angle detection sensor control unit 140: Drive control unit 142: Movement Control Unit 144: Arithmetic section 146: Inclination Control Unit 150: Storage section 200: Bending program D: Lower mold F: Bending line P: Upper mold RP: Center of rotation W: Work

Claims

1. The lower table on which the lower mold is attached, An upper table is fitted with an upper mold and is configured to be movable relative to the lower table, and is configured to be adjustable in the vertical direction. Equipped with, A basic bending process is performed on a workpiece inserted between the upper die and the lower die, which is bent towards a predetermined bending angle. An additional bending process is performed on the workpiece on which the basic bending process described above has been carried out, in which additional bending is performed on the parts where the bending angle is insufficient. It is configured to be executable, The additional bending process is performed by raising one end of the upper table while lowering the other end, with respect to at least one of the rotation centers, which are either a rotation center designated at an arbitrary position in the longitudinal direction of the upper table or a rotation center set at a predetermined position in the longitudinal direction of the upper table. Press brake.

2. A lower table on which the lower mold is mounted, An upper table is fitted with an upper mold and is configured to be movable relative to the lower table, and is configured to be adjustable in the vertical direction. Equipped with, A basic bending process is performed on a workpiece inserted between the upper die and the lower die, which is bent towards a predetermined bending angle. An additional bending process is performed on the workpiece on which the basic bending process described above has been carried out, in which additional bending is performed on the parts where the bending angle is insufficient. It is configured to be executable, The aforementioned additional bending process is performed by raising one end of the upper table while lowering the other end. The system further includes a rotation center designation unit that can specify the rotation center of the tilt of the upper table, The upper table is configured to allow adjustment of its tilt around the rotation center specified by the rotation center designation unit. Press brake.

3. A lower table on which the lower mold is mounted, An upper table is fitted with an upper mold and is configured to be movable relative to the lower table, and is configured to be adjustable in the vertical direction. Equipped with, A basic bending process is performed on a workpiece inserted between the upper die and the lower die, which is bent towards a predetermined bending angle. An additional bending process is performed on the workpiece on which the basic bending process described above has been carried out, in which additional bending is performed on the parts where the bending angle is insufficient. It is configured to be executable, The aforementioned additional bending process is performed by raising one end of the upper table while lowering the other end. The system further includes an angle detection sensor capable of detecting the bending angle of a workpiece on which the basic bending process described above has been performed. The angle detection sensor is configured to be movable in the left-right direction of the upper table and the lower table. The system further comprises a control unit that controls the operation of the upper table, The control unit, A calculation unit that calculates the rotation center of the upper table based on information regarding the bending angle of the workpiece detected by the angle detection sensor, The tilt control unit that can control the tilt of the upper table and Includes, The tilt control unit, when executing the additional bending process, raises one end of the upper table while lowering the other end, with respect to the rotation center calculated by the calculation unit. Press brake.

4. The upper table is equipped with a tilting control unit that allows the operator to tilt the upper table. A press brake according to any one of claims 1 to 3.

5. The lower table on which the lower mold is attached, An upper table is fitted with an upper mold and is configured to be movable relative to the lower table, and is configured to be adjustable in the vertical direction. In a bending process that processes a workpiece using a press brake equipped with, A basic bending process in which a workpiece inserted between the upper die and the lower die is bent toward a predetermined bending angle, An additional bending process is performed on the workpiece in which the basic bending process described above has been carried out, in which additional bending is performed on the parts where the bending angle is insufficient. Includes, The additional bending step is performed by raising one end of the upper table while lowering the other end, with respect to at least one of the rotation centers, which are specified at any position in the longitudinal direction of the upper table or set at a predetermined position in the longitudinal direction of the upper table. Bending process.

6. The lower table on which the lower mold is attached, An upper table is fitted with an upper mold and is configured to be movable relative to the lower table, and is configured to be adjustable in the vertical direction. A control unit that controls the operation of the upper table and In a bending program that processes a workpiece using a press brake equipped with, A basic bending process is performed on a workpiece inserted between the upper die and the lower die, which is bent towards a predetermined bending angle. An additional bending process is performed on the workpiece on which the basic bending process described above has been carried out, in which additional bending is performed on the parts where the bending angle is insufficient. The system is configured to cause the control unit to execute the following: The additional bending process is performed by raising one end of the upper table while lowering the other end, with respect to at least one of the rotation centers, which are either a rotation center designated at an arbitrary position in the longitudinal direction of the upper table or a rotation center set at a predetermined position in the longitudinal direction of the upper table. Bending program.

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