JP4965368B2 - Bending system and bending method - Google Patents

Description

  The present invention relates to a bending processing system and a bending processing method, and in particular, a bending that moves an imaging machine to an appropriate position and focuses according to the position of the workpiece, images the bending shape of the workpiece, and appropriately inspects the bending angle. The present invention relates to a processing system and a bending method.

  Conventionally, a process of bending is included in the process of processing and commercializing a plate material. Various angle sensors that are mounted on a bending machine and measure a bending angle in-line are devised and put into practical use regardless of contact type or non-contact type.

  On the other hand, these angle sensors have been put into practical use in V-bending machines using V-shaped punches and dies. For example, they are fixed by sandwiching a workpiece, and a standard bend beam mold is used for this workpiece. There is no implementation or proposal for a processing machine that performs bending (hereinafter referred to as ironing bending) using a certain forward bending die or reverse bending die.

See also Patent Document 1 and Patent Document 2.
JP-A-7-275952 Japanese Patent Laid-Open No. 11-216520

  In a bending machine (especially a bending machine that performs ironing bending), for example, when measuring the angle of a bending flange with an angle sensor, the operating range of the ironing bending mold is wide and complicated, so a sensor is installed. There is a problem that there is no place to do.

  In the case of iron bending, the processing method includes normal bending and reverse bending, and the angle measurement range is wide from an acute angle bending of about 30 degrees to an obtuse angle bending of about 180 degrees. The required angle measurement width is 180 degrees −30 degrees = 150 degrees in forward bending, and reaches 300 degrees when including reverse bending. In the case of angle sensors that have been put into practical use, the angle measurement width is up to about 60 degrees, and this limit is apparent from the angle measurement principle.

  On the other hand, when application of an angle sensor to iron bending is considered, a method of measuring the angle of the bending flange of the workpiece by image processing from image data of an image captured of the workpiece end surface using an imaging device such as a CCD camera is conceivable. . However, in this case as well, there is a problem that it is difficult to save space because a large space is required at the installation location.

  Furthermore, not only the image of the workpiece end face, but also the image of the mold that bends the workpiece provided in the bending machine and the back gauge that determines the bending position of the workpiece are reflected in the image captured by the camera during bending. . Then, there is a problem that the edge portion of the work flange to be measured must be recognized from the image data of the image, and the angle (bending angle) of the straight portion of the edge portion must be measured.

  Moreover, the image of the workpiece end surface after bending a plurality of processes when there are a plurality of bending processes has bending flanges for the processes that have been bent so far. Among the plurality of flanges, there is a problem that only the currently bent flange must be recognized and the angle of the straight portion of the edge portion of the flange must be measured.

  In the case of R-bending, the bent part of the workpiece is curved, and in order to measure the edge angle of the flange part that is continuous with this R-bent part, the edge part where the curved part of the flange ends and becomes a straight line is recognized. There was a problem that the angle had to be measured for the straight line of this edge.

  As described above, there is no method for reliably recognizing a desired bending flange from image data in various bending processes on an inline of a bending machine and measuring the angle of the straight line portion, and the above problem cannot be solved. In addition to the desired flange, for example, the angle of the straight part of the mold may be measured and the wrong angle may be corrected. There is a problem that there is a danger to the operator or processing machine due to processing failure or abnormal pressurization. there were.

The invention according to claim 1 is a bending system for bending a workpiece with a mold.
An imager that images the shape of a workpiece bent by the mold, a moving device that moves and positions the imager to a predetermined position, a moving device control unit that controls the moving device, and an image of the workpiece A light reflecting member that reflects a predetermined angle toward the image pickup device,
The moving device control means performs control to move the image pickup device according to the position of the imaging location of the workpiece that is installed, the distance from the imaging location of the workpiece to the light reflecting member, and the light reflecting member A bending processing system that keeps the total distance from the image pickup device to an appropriate focal length.

  The invention according to claim 2 is a configuration in which the light reflecting member that reflects the image of the workpiece at a predetermined angle toward the imaging device reflects the image of the workpiece from a horizontal direction to a vertical direction. Bending system.

  The invention according to claim 3 includes a surface light source that irradiates light to the workpiece, the workpiece is disposed between the surface light source and the light reflecting member, and the surface light source is light with respect to the workpiece. The bending processing system according to claim 1, wherein the bending processing system is irradiated.

The invention according to claim 4 is a bending method for bending a workpiece with a mold.
The moving device control means controls the moving device to move and position the image pickup device to a predetermined position, the light reflecting member reflects the image of the workpiece toward the image pickup device at a predetermined angle, and the image pickup device bends the mold. While taking an image of the shape of the workpiece,
The moving device control means performs control to move the image pickup device according to the position of the imaging location of the workpiece that is installed, the distance from the imaging location of the workpiece to the light reflecting member, and the light reflecting member Is a bending method for keeping the total distance from the image pickup device to an appropriate focal length.

The invention according to claim 5 is a bending system for bending a workpiece with a mold.
An imaging device that images the flange shape of the workpiece bent by the mold, a storage unit that stores a reference flange image in advance, a matching unit that matches the captured flange image, and the reference flange image, and the matching unit Bending angle calculation means for obtaining an angle between the reference flange image and the flange image based on the matching of
In the bending system, the flange image in a set region is specified, and a matching angle with the reference flange image is obtained.

  The invention according to claim 6 is the bending system according to claim 5, further comprising an exclusion unit that excludes an image outside the set area.

  The invention according to claim 7 is the bending system according to claim 5 or 6, wherein the set area is fan-shaped.

The invention according to claim 8 is a bending method for bending a workpiece with a mold.
The image of the flange shape of the workpiece bent by the mold is picked up by the image pickup device, the reference flange image stored in advance in the storage means is taken out, and the matching means matches the picked flange image with the reference flange image. The bending angle calculation means performs a process for obtaining an angle between the reference flange image and the flange image based on the matching of the matching means,
Further, it is a bending method in which the flange image in the set region is specified and the matching angle with the reference flange image is obtained.

  According to the present invention, first, there is an effect that space saving is possible. That is, since the imaging path to the workpiece and the imaging device is not a straight line due to the light reflecting member, there is an effect that the spread can be suppressed and the space can be reduced and the space can be saved.

  Secondly, the angle when the work (plate material) is bent can be accurately obtained. For example, the bending portion of the workpiece is curved, and in order to measure the bending angle, the edge portion that becomes a straight line after the curved curve portion of the flange is recognized, and the linear portion of this edge portion can be measured.

  In other words, in pattern matching, an area composed only of a straight line portion and not including a curved portion is higher in correlation value than an image area including a curved portion at an edge. The angle can be determined. In addition, accurate measurement can be performed even without R bending.

  If the inspection area is fan-shaped, images other than the desired work flange can be ignored, and the following effects can be obtained. That is, the image captured by the camera does not include not only the image of the workpiece end face but also the image of the mold and back gauge provided in the processing machine, and therefore the flange portion can be accurately recognized.

  1 is a perspective view showing a schematic configuration of the entire bending unit 1 according to the present invention, and FIG. 2 is a perspective view showing a schematic configuration of a portion on the bending machine 5 side in the bending unit 1. 3 is a side view showing a schematic configuration of the entire bending unit 1.

  In this example, for convenience of explanation, one horizontal direction is defined as the X-axis direction, another horizontal direction perpendicular to the X-axis direction is defined as the Y-axis direction, and the vertical direction (vertical direction) is defined as the Z-axis direction. May be a direction.

  Please refer to FIG. 1, FIG. 2 and FIG. The bending unit 1 has a work table 3 on which a thin plate-like workpiece (for example, a metal workpiece) W is placed such that the thickness direction of the workpiece W is in the vertical direction.

  A flat surface is provided on the upper part of the work table 3, and the work W is directly placed on the flat surface (upper surface) by contacting the work W, but a brush is placed on the upper surface of the work table 3. An appropriate number of hair transplants or free bears (registered trademark) may be provided, and the work W may be placed indirectly by bringing the upper end of the brush or the upper end of the free bear into contact with the work W. The height position of the lower surface of the workpiece W when the workpiece W is placed directly or when the workpiece W is placed indirectly may be referred to as a “work pass line”.

  A bending machine 5 for bending the work W is provided on one side of the work table 3 in the longitudinal direction (Y-axis direction). Further, the bending unit 1 is provided with a manipulator 7 for holding the workpiece W placed on the workpiece table 3. The manipulator 7 moves and positions the workpiece W placed and held on the workpiece table 3 so as to be processed by the bending machine 5.

  The work table 3, the bending machine 5 and the manipulator 7 are covered with a safety enclosure 9. The safety enclosure 9 is provided with a door 11 that can be opened and closed. When the door 11 is closed, the safety of the operator during the operation of the bending unit 1 is ensured. Further, the door 11 is provided for loading the work W into the work table 3 and placing it, and for unloading the work W placed on the work table 3 from the work table 3. That is, the work W is carried into the work table 3 through the opened door 11 and the work W is carried out from the work table 3. The door 11 is provided, for example, on the side opposite to the bending machine 5 in the longitudinal direction (Y-axis direction) of the work table 3.

  The bending unit 1 is provided with a workpiece transfer means 13 (see FIG. 4) and a workpiece positioning means 15 (see FIG. 4). The workpiece transfer means 13 transfers the workpiece W placed on the workpiece table 3 in the vicinity of the door 11 to a position where the workpiece W can be held by the manipulator 7 while being placed on the workpiece table 3.

  The work positioning means 15 can hold the work W placed on the work table 3 at a predetermined position (for example, the center of the work W by the manipulator 7) before being held by the manipulator 7 (immediately before). Position). It is assumed that the workpiece transfer means 13 and the workpiece positioning means 15 are surrounded by a safety enclosure 9.

  The bending unit 1 will be described in more detail with an example. The upper surface of the work table 3 is formed in a rectangular shape in plan view. As described above, the Y-axis direction is the longitudinal direction of the work table 3, and the X-axis direction is the width direction of the work table 3. ing. In addition, although it is a form of the upper surface of the work table 3, a square may be sufficient and the dimension (width) of the width direction may be larger or smaller than the dimension (length) of a longitudinal direction.

  The bending machine 5 is configured to perform a so-called ironing bending process on the workpiece W (for example, see Japanese Patent Application No. 2004-292172).

  That is, as shown in FIG. 3, the bending machine 5 includes a portal frame (for example, a portal frame provided integrally with the work table 3) 17, and the portal frame 17 extends in the X-axis direction. A ram drive source 19 (for example, a motor M and a ball screw / nut mechanism) is installed at both inner ends. With this configuration, when the ram drive source 19 is operated, the ram 21 guided by the frame 17 moves linearly in the vertical direction (Z-axis direction) and can be positioned at a predetermined position.

  A lower table 23 facing the ram 21 is disposed below the ram 21. The lower table 23 is provided integrally with the portal frame 17. A lower plate presser 25 is integrally provided at the upper end of the lower table 23. Note that the upper surface of the lower plate holder 25 is formed in an elongated rectangular shape having a predetermined width in the Y-axis direction and substantially the same length as the width of the work table 3 in the X-axis direction. It is located at almost the same height as the pass line.

  An upper plate presser 27 is integrally provided at the lower end of the ram 21. The lower surface of the upper plate holder 27 is formed in substantially the same shape as the upper surface of the lower plate holder 25 and faces the upper surface of the lower plate holder 25.

  As is well known, a bend beam 33 that moves in the vertical direction (Z-axis direction) and the front-rear direction (Y-axis direction) is located behind the lower table 25 via the D-axis 29 and the A-axis 31. The bend beam 33 is installed on a lower frame (a lower frame provided integrally with the frame 17) 35. The bend beam 33 is, for example, a standard bending die 33A or a reverse bending die 33B. The ironing and bending process.

  As already understood, the ram 21, the lower table 23, the lower plate holder 25, and the upper plate holder 27 exist between the work table 3 and the bend beam 33 in the Y-axis direction. Further, when ironing and bending the workpiece W, the workpiece W is clamped by the lower plate presser 25 and the upper plate presser 27.

  Further, the bending machine 5 may be configured to be capable of selectively switching between V-bending and ironing bending as described in the specification of Japanese Patent Application No. 2004-292172. The configuration described in the specification of 292172 may be changed as appropriate so that only V-bending is performed. Furthermore, you may be comprised so that a bending process may be performed by another system.

  The manipulator 7 cooperates with the lower holder 37 for the gate-shaped frame 35, the lower holder 37 for placing the work W placed on the work table 3, and the work W placed on the work table 3. An upper holder 39 for sandwiching and holding is provided.

  The gate-shaped frame 35 includes upper columns 41 </ b> A and 41 </ b> B standing on both sides in the width direction (X-axis direction) of the work table 3 and upper beams connecting the upper ends of the respective columns 41 </ b> A and 41 </ b> B to each other. 43 is formed in a gate shape. Each support column 41A, 41B is slightly separated from the work table 3 on both sides in the width direction of the work table 3, and stands at substantially the same position in the longitudinal direction of the work table 3 (Y-axis direction). It exists away from the upper surface of the work table 3 (the upper end of these if a brush or a free bear is provided), and extends in the width direction of the work table 3.

  In addition, a lower beam 45 that connects the lower ends of the columns 41A and 41B to each other is integrally provided on the portal frame 35. By providing the lower beam 45, it can be said that the frame 35 is formed in a "B" shape.

  The frame 35 is movable in the Y-axis direction with respect to the work table 3 via a linear guide bearing 47, and is positioned in the Y-axis direction by a servo motor 49 and a ball screw 51 as an example of an actuator. It is free.

  A lower holder 37 is rotatably provided on the lower beam 45 of the frame 35 via a bearing (not shown). The lower holder 37 has a circular flat surface at the upper end, and this flat surface (upper surface) is located at almost the same height as the pass line of the workpiece W. In order to make it easier to hold the workpiece W and to move the held workpiece W, the upper surface of the lower holder 37 is slightly lower than the pass line of the workpiece W and slightly higher than the pass line of the workpiece W. It may be configured such that it is moved and positioned between high positions and can be held at the positioned positions. Furthermore, the upper surface of the lower holder 37 is higher than the pass line of the workpiece W in order to prevent the workpiece W from interfering with the lower plate presser 25 when the workpiece W is moved downward by bending. It is good also as a structure which can move to a position.

  The lower holder 37 has an axis extending in the Z-axis direction and passing through the center of the upper surface of the lower holder 37 as a rotation center so that the lower beam 45 can be indexed by a servo motor 53 as an example of an actuator. It has become. A circular flat surface (lower surface) facing the upper surface of the lower holder 37 is provided at the lower end of the upper holder 39, and the upper holder 39 is supported by a linear guide bearing 55, and is a fluid that is an example of an actuator. The pressure cylinder 57 can move up and down with respect to the upper beam 43 of the frame 35. Further, it is supported by a bearing (not shown) and is rotatable about the same axis as the lower holder 37.

  With this configuration, the gate-shaped frame 35, the upper holder 39, and the lower holder 37 are moved in the extending direction of the upper surface of the work table 3 (that is, the longitudinal direction of the work table 3) in synchronization with each other. It is configured to be freely positionable. Further, by lowering the upper holder 39, the work W placed on the work table 3 can be sandwiched and held in a state as it is (without changing the position and posture of the work W). It is like that.

  The workpiece W held by the upper holder 39 and the lower holder 37 can be moved and positioned in the Y-axis direction, and is an axis extending in the vertical direction. Index positioning is possible with the axis passing through the center of rotation.

  A groove (work table groove) 59 having a predetermined width extending in the longitudinal direction of the work table 3 is provided at a substantially central portion of the work table 3 in the width direction, and the lower holder 37 moves in the groove 59. It is supposed to be. Further, the lower holder 37 and the upper holder 39 are provided on the bending machine 5 side with respect to the frame 35 in order to facilitate bending to a small workpiece W.

  FIG. 4 is a plan view showing a specific example of the workpiece transfer means 13 and the workpiece positioning means 15. Please refer to FIG. The workpiece transfer means 13 is configured to transfer the workpiece W by pressing the workpiece table groove 59 with the workpiece support members 63A and 63B that are movable in the longitudinal direction of the workpiece table 3.

  More specifically, a rotating member (not shown) such as a sprocket is provided to be rotatable with respect to the work table 3 at one end in the longitudinal direction of the work table 3 below the upper surface of the work table 3. The rotating member is driven to rotate by an actuator (not shown) such as a motor. The rotating member exists at substantially the same position as the work support member 63A in the width direction of the work table 3.

  In addition, a rotating member (not shown) such as a sprocket is provided to be rotatable with respect to the work table 3 at the other end in the longitudinal direction of the work table 3 below the upper surface of the work table 3. . An annular member such as a chain is wound around each rotating member. A work support member 63A is integrally provided on the wound annular member. The annular member is positioned below the upper surface of the work table 3, but the upper portion of the work support member 63 </ b> A protrudes above the upper surface of the work table 3.

  The work support member 63B is also provided in another chain or the like, similarly to the work support member 63A. Then, when a rotating member such as a sprocket is appropriately rotated, the workpiece support members 63A and 63B are synchronously moved in the Y-axis direction (extending direction of the groove 59), and the workpiece W placed on the workpiece table 3 is moved. It can be moved by pressing.

  That is, the work W placed on the work table 3 and existing at the position PS1 shown in FIG. 4 is pushed while being placed on the work table 3 to the position PS3 (position that can be positioned by the work positioning means 15). It can be transported.

  By the way, in the above description, the workpiece W placed on the workpiece table 3 in the vicinity of the door 11 is transferred to a position that can be positioned by the workpiece positioning means 15 (a position that can be held by the manipulator 7). Further, it may be transferred to another position that can be held by the manipulator 7. In this case, the work W placed on the work table 3 in the vicinity of the door 11 is located at another position that can be held by the manipulator 7 (for example, in the middle of PS1 and PS3 in the Y-axis direction in FIG. 4). ), And thereafter, it is carried by the manipulator 7 to a position that can be positioned by the work positioning means 15 (position of PS3).

  In addition, by rotating the rotating member such as the sprocket in the reverse direction (the rotation opposite to the case where the workpiece W is pushed from the position PS1 to the position PS3), the workpiece W existing at the position PS3 is moved to the position PS1. It can be pushed and transferred.

  Therefore, if the workpiece transfer means 13 is used, the workpiece W placed on the workpiece table 3 in the vicinity of the door 11 can be transferred to a position where the manipulator 7 can hold the workpiece W. The work held by the manipulator 7 can also be transferred to the vicinity of the door 11.

  In the workpiece transfer means 13 described above, the workpiece W is pushed and transferred by the workpiece support members 63A and 63B, but the ends of the workpiece W are held by the members 65A and 65B indicated by the two-dot chain lines in FIG. For example, the workpiece W may be pinched and transferred while pulling the workpiece W. Furthermore, the structure which hold | maintains the workpiece | work W, pushes the workpiece | work W, and may transfer may be sufficient.

  By providing the workpiece transfer means 13 described above, the manipulator 7 does not need to move over almost the entire length of the work table 3 in the longitudinal direction (Y-axis direction), and at least approximately the central portion of the work table 3 in the longitudinal direction. And the end of the work table 3 in the longitudinal direction on the bending machine 5 side can be moved and positioned. That is, if each holder 37, 39 can be moved and positioned between the position PS5 and a position slightly to the right of the position PS7 (right side in FIG. 4) as shown by a two-dot chain line in FIG. Good.

  The work positioning means 15 is configured by pins 67A, 67B, 69A, 69B that can be moved in and out with respect to the upper surface of the work table 3, and work support members 63A, 63B. Each pin 67A, 67B, 69A, 69B is moved up and down by an actuator such as a fluid pressure cylinder.

  More specifically, each pin 67A, 67B is provided on the bending machine 5 side in the longitudinal direction of the work table 3, and in the state where each pin 67A, 67B protrudes from the upper surface of the work table 3, When the workpiece is pushed by the support members 63A and 63B and the workpiece W is abutted against the pins 67A and 67B, the workpiece W is positioned in the Y-axis direction.

  Each pin 69A, 69B is provided on the bending machine 5 side in the longitudinal direction of the work table 3, and is movable in the width direction (X-axis direction) of the work table 3. However, each of the pins 69A and 69B is moved in the opposite direction in synchronization by a mechanism such as a link mechanism or a rack and pinion, and sandwiches the workpiece W so that the center of the workpiece W is the center in the width direction of the workpiece table 3. Positioning can be performed in the X-axis direction so as to substantially match.

  In addition to the pins 67A, 67B, 69A, and 69B, the workpiece W may be positioned by using the units 71A and 71B indicated by two-dot chain lines in FIG.

  That is, after positioning the workpiece W with the pins 67A, 67B, 69A, 69B, etc., the pins 67A, 67B, 69A, 69B are retracted from the upper surface of the work table 3. Thereafter, as described in JP-A-11-226677, each unit 71A, 71B is used to hold (for example, hold) the end portion of the workpiece W and pull the workpiece W in the horizontal direction (X-axis direction). (/ Y-axis direction) and positioning may be performed.

  FIG. 5 is a configuration diagram illustrating a configuration in which the workpiece bent by the bending machine 5 (see FIGS. 1 to 3) is imaged by the imaging device 87.

  As shown in FIG. 5 (the positional relationship with the bending machine 5 is shown in FIGS. 1 to 3), the imaging device 87 for imaging the shape of the workpiece W bent by the molds 33A and 33B, and the imaging device 87 are predetermined. A moving device (support member 81, guide rail 83, guide member 89, connecting member 85) for moving and positioning in the direction, a moving device control means (not shown) for controlling the moving device, and an image of the workpiece on the image pickup device 87. And a light reflecting member (reflecting mirror) 91 that reflects the light by a predetermined angle.

  Here, the support member 81 is fixed to a predetermined position of the bending machine 5. The guide rail 83 is positioned at an appropriate position on the support member 81.

  The image pickup device 87 is fixed to the guide 89 that is movable on the guide rail 83 in the Z-axis direction (arrow AR direction). The image pickup device 87 is configured to move by movement of the connecting member 85 attached to the guide 89 in the Z-axis direction (arrow AR direction). Here, the driving means of the connecting member 85 is a ball screw mechanism or a cylinder.

  Thereby, the moving device (the support member 81, the guide rail 83, the guide member 89, and the connecting member 85) controls to move the image pickup device 87 in accordance with the position of the imaging position of the work W installed (end surface position of the work). Thus, the total value of the distance from the imaging position of the workpiece W to the light reflecting member 91 and the distance from the light reflecting member 91 to the imaging device 87 can be kept constant.

  Here, in the light reflecting member (reflecting mirror) 91 that reflects the image of the work W in the direction of the imaging device 87 by a predetermined angle, the light reflecting member 91 changes the image of the work W from the horizontal direction (X-axis direction) to the vertical direction ( Reflected in the Z-axis direction). Thereby, the installation space etc. of the bending machine 5 can be reduced.

  Furthermore, the surface light source 93 which irradiates light to the workpiece | work W is provided, the workpiece | work W is arrange | positioned between the surface light source 93 and the light reflection member 91, the surface light source 93 irradiates light with respect to the workpiece | work W, light An image of the workpiece W is projected on the reflecting member 91.

  6 and 7 show the moving state of the image pickup device 87 by controlling the moving device (support member 81, guide rail 83, guide member 89, connecting member 85).

  As shown in FIG. 6, it is assumed that the width of the workpiece W is 1 and the center of the width of the workpiece W coincides with the reference line C of the bending machine. At this time, the image pickup device satisfies the relationship of A1 (distance from the end surface of the workpiece W to the light reflecting member 91) + B1 (distance from the light reflecting member 91 to the image pickup device 87) = D (distance where the focus is appropriate). Control is performed to move the position 87 in the Z-axis direction.

  On the other hand, as shown in FIG. 7, it is assumed that the width of the workpiece W is 1 and the center of the width of the workpiece W is a position away from the reference line C of the bending machine by an x value. At this time, imaging is performed so as to satisfy the relationship of A2 (distance from the end surface of the workpiece W to the light reflecting member 91) + B2 (distance from the light reflecting member 91 to the imaging device 87) = D (distance where the focus is appropriate). Control to move the position of the machine 87 in the Z-axis direction is performed.

  In the above description, the width of the workpiece W can be obtained from the graphic data, and the moving distance of the workpiece W can be obtained from the control data of the bending machine 5 or the like. It is possible to make the distance to the imaging device 87 constant according to a change (when the workpiece W is exchanged, when the workpiece W moves, etc.).

  Thereby, the total distance from the end face position of the workpiece W to the position of the image pickup device 87 is kept constant, the focal point is always appropriate, and the installation space for the bending machine 5 can be significantly reduced.

  The operation of the bending unit 1 will be described with reference to FIG.

  As an initial state, the workpiece W is not contained in the bending unit 1, the workpiece support members 63 </ b> A, 63 </ b> B are present at the positions shown in FIG. 4, and the pins 67 </ b> A, 67 </ b> B, 69 </ b> A, 69 </ b> B It is assumed that the pins 69 </ b> A and 69 </ b> B are located outside in the width direction of the work table 3.

  Further, it is assumed that the holders 37 and 39 of the manipulator 7 are present at the position PS5 shown in FIG. 4, the upper holder 39 is raised, and the upper plate holder 27 of the bending machine 5 is also raised.

  In step S01, in the NC device 79 (see FIG. 3) which is an example of the control device, the workpiece information (for example, the machining data of the workpiece W, the installation position of the workpiece W, the shape of the workpiece W, the width of the workpiece W, etc.) It is input via an input means (not shown) (touch panel or the like). Here, by inputting the workpiece information of the workpiece W, the width of the workpiece W and the installation position of the workpiece W can be known, so that the position of the end face of the workpiece W can also be specified.

  In step S03, the imaging device 87 is positioned at a predetermined position. That is, as described above, assuming that the width of the workpiece W is 1 and the center of the width of the workpiece W coincides with the reference line C of the bending machine 5, A1 (from the end face of the workpiece W to the light reflecting member) The position of the image pickup device 87 is moved in the Z-axis direction so as to satisfy the relationship of (distance to 91) + B1 (distance from the light reflecting member 91 to the image pickup device 87) = D (distance where the focal point is appropriate).

  In step S05 and step S07, in the initial state, when the operator places the workpiece W at the position PS1 on the work table 3 and presses the start button of the NC device 79, the door 11 is controlled under the control of the NC device 79. The workpiece support members 63A and 63B are moved rightward in FIG. 4 to transfer the workpiece W to the position PS3 (the position where the workpiece W hits the pins 67A and 67B).

  4 shows a small work W, the movement distance of each work support member 63A, 63B is large when the work W is transferred, but the size of the work W is almost the same as the upper surface of the work table 3. If it is larger, the workpiece support members 63A and 63B move the workpiece W with little movement.

  Then, the workpiece W is positioned with respect to the machine. That is, the pins 69A and 69B are moved toward the center of the work table 3 to position the work W, and the manipulator 7 is moved and positioned so that the holders 37 and 39 are located at the positions of PS7. The pins 67A, 67B, 69A, 69B are retracted from the upper surface of the work table 3, the upper holder 39 is lowered to clamp the substantially central portion of the work W, and the manipulator 7 is appropriately positioned in the Y-axis direction.

  In steps S09 and S11, the upper plate holder 27 is lowered to clamp the workpiece W, and the bending machine 5 drives the bend beam to perform bending on the workpiece W.

  In step S13, the bending angle of the portion where the workpiece W is bent is measured. In step S15, it is determined whether the bending angle is an allowable value.

  When the bending angle is within the allowable range, the processing continues to raise the upper plate holder 27, move the manipulator 7 to move the workpiece W away from the bending machine 5, position the workpiece W as an index, and so on. Then perform the following bending process.

  If the bending angle is not within the allowable value, the process proceeds to step S17.

  In step S17, a bending correction stroke is calculated with reference to the bending angle. Subsequently, the process returns to step S11.

  Please refer to FIG. 9 and FIG. A method of bending the workpiece W and bending it again according to the result of angle detection will be described. As shown in FIG. 9, the bending machine 5 is provided with a surface light source 93 at one end and a light reflecting member 91 at the other end, and an image obtained by bending the workpiece W from the horizontal direction (X-axis direction) to the vertical direction. The image is taken in the Z-axis direction, and the imaging device 87 images the workpiece W. Subsequently, the captured image data is transmitted to the image processing device 95, and it is determined whether or not the bending angle is within the allowable range. When the value is outside the allowable range, control data for bending correction is transmitted to the control device 97. Then, as shown in FIG. 10, a bending correction process is performed on the workpiece W fixed by the lower presser 25 and the upper presser 27 by the normal bending die 33A.

  When all the bending processes are completed, the manipulator 7 is positioned at an appropriate position, the upper holder 39 is lifted to release the workpiece W from being clamped by the manipulator 7, and the workpiece support members 63A and 63B are used to attach the workpiece W to the door 11. Then, the pins 67A, 67B, 69A, 69B are raised, the door 11 is lowered, the operator carries the workpiece, and returns to the initial state.

  Here, the image processing in step S13 described above will be described in detail below.

  FIG. 11 shows the image processing apparatus 95.

  The image processing device 95 includes an A / D conversion converter 99, an image memory 101, a measurement area pattern memory 103, a combining unit (corresponding to a matching unit in claims) 105, a reference pattern memory 107, and a pattern matching processing unit. (Corresponding to a matching means in claims) 109, an angle calculation unit (corresponding to an angle calculation means in claims) 111, and an output processing unit 113.

  The A / D conversion converter 99 receives an image of the workpiece W that has been bent from the image pickup device 87, and performs A / D conversion.

  The image memory 101 stores A / D converted bending image data. The measurement area pattern memory 103 stores image data in which a region to be measured is set. In this example, a fan-shaped measurement area is set. In this example, the fan shape refers to a closed figure in which two arcs having different radii and the same center (the center of a circle on which the arc is based) are connected to each other and the end points of each arc.

  The combining unit 105 combines the image data stored in the image memory 101 and the image data stored in the measurement pattern memory 103. At the time of the synthesis, the positional relationship to be synthesized is determined in advance, and after the synthesis, the fan-shaped arc is synthesized so as to surround the bending flange in accordance with the bending angle method of the bending flange of the workpiece W. .

  The pattern matching processing unit 109 reads the reference pattern P from the reference pattern memory 107 that stores the reference pattern P. Here, the reference pattern P refers to a part of the flange shape of the workpiece W when the bending angle is 0 degree or 180 degrees.

  The angle calculation unit 111 translates / rotates the reference pattern, and searches for the shape portion closest to the flange of the imaged workpiece W. Then, the rotation angle when searched is the bending angle. Then, the output processing unit 113 transmits the data of the bending angle θ to the bending machine control device 97 and performs angle correction.

  Here, the bending machine 5 roughly includes a V-shaped bending machine using a V-shaped punch and a die, and an iron bending machine. The following is an example of an iron bending machine, but it can also be applied to a V bending machine. As described above, the iron bending machine sandwiches a material between an upper plate pressing die and a lower plate pressing die, and bends the material with a bending die. The bending machine 5 and the control device 97 perform bending of the material by controlling the axis of the bending machine 5 based on pre-programmed bending information.

  Further, the imaging device 87 images the end face of the bent work W. The image pickup device 87 is generally called a CCD camera because a CCD is often used as an image pickup device. In this example, the imaging device 87 is not particularly limited, and a CMOS camera or an imaging tube type may be used.

  As described above, the image processing device 95 digitizes the image data sent from the image pickup device 87 in a time series, stores it in the image memory, and performs pattern matching with a reference pattern registered in advance. This reference pattern is obtained by cutting out a part of the end face of the workpiece W placed at a position of 180 degrees in the longitudinal direction. In the pattern matching process, a pattern having the highest correlation with the reference pattern is searched, and a deviation amount in the rotation direction from the reference pattern is calculated. Since the amount of deviation in the rotational direction corresponds to the bending angle of the material with 180 degrees as a reference, the measurement angle of the material is used. The series of processes in the image processing device 95 is performed by a measurement command from the control device 97 of the bending machine 5 connected to the image processing device 95, and the measurement angle is returned to the control device 97.

  Please refer to FIG. In the image processing device 95, after the image data is taken from the image pickup device 87 and stored in the image memory 101, the straight portion of the flange of the workpiece W as the material to be measured is recognized, and the angle of this straight portion is changed to the bending angle. Will be described.

  First, a pattern matching algorithm in image processing will be described.

  The basic idea is to create a reference pattern P that is a reference of 180 degrees and store it in the reference pattern memory 107 in advance. A difference is calculated when the image is overlapped with a part of the image F of the end face of the work W taken into the image memory 101 sufficiently larger than the reference pattern P. The calculation of the difference at each position is performed while shifting the entire image left and right and up and down, and it is determined that the position where the difference is the smallest is the image pattern that best matches the reference pattern P.

This is represented by the general formula 1.

  E (x, y) is a difference from the reference pattern P at the position (x, y) in the image F. The smaller E (x, y), the higher the correlation (that is, the higher the matching degree), and the smallest position is searched.

By extending this, pattern matching is performed in consideration of not only X and Y displacement but also the rotation direction. For this purpose, pattern matching is performed at 360 ° while rotating the coordinates by a predetermined angle at each X and Y position. If the pattern subjected to the angle conversion is P ′, Equation 2 is obtained.

This is combined with Equation 1 to obtain Equation 3.

  Thus, it is only necessary to find X, Y, and θ so that E (x, y) is minimized. Although these calculation processes are enormous data processes, the results can be obtained in a short time by performing the process by hardware.

  The angle θ obtained by the pattern matching process can be an angle difference between the end face of the work W placed at the position of 180 degrees registered as the reference pattern P and the end face of the work W in the image F. . By this method, it is possible to accurately measure the angle of the linear portion of the end face of the workpiece W.

  Please refer to FIG. In the bending method of the workpiece W, there is so-called R bending. This is a bending process with a large radius R.

  In this processing, in order to measure the bending angle of the workpiece W, it is necessary to recognize a straight line portion where the curved portion R of the end surface of the workpiece W is completed. If the above method is used, since the correlation of the end face pattern P1 of the workpiece W including the bending line portion R is low, the end face pattern P2 of the workpiece W including only the straight portion can be recognized. Thereby, an accurate angle measurement can be performed also in R bending.

  Refer to FIG. In the image data captured and captured by the imager 87, in addition to the end face of the workpiece W, an image of the mold 33, the material pressing device (25, 27), or the like may be displayed. In particular, since it is always reflected during bending, since the reference pattern P is a part of the straight line of the end face of the workpiece W in the pattern matching, a high correlation value is obtained in the straight part of the mold 33 or the like by mistake. Therefore, the angle of this straight line portion may be obtained.

  Refer to FIG. When the workpiece W is bent, in most cases, not only one side is bent but a plurality of bending steps are continuously processed. In the case of bending work for the second and subsequent sides, the image data includes the end face FR1 of the first side already bent and the end face FR2 of the second side being processed. The end face to be recognized at this time is naturally the end face FR2 on the second side, and the end face FR1 on the first side must not be mistakenly recognized.

  In order to prevent erroneous measurement as described above, in this example, a fan-shaped measurement area pattern centered on the bending position of the workpiece W is appropriate. The measurement area pattern is an area in which pattern matching is set in the image data. Only the image data in this area is processed, and the outside of the area is excluded.

  Here, the fan shape refers to a closed figure in which two arcs having different radii and the same center (center of a circle on which the arc is based) are connected to each other and the end points of each arc. Then, the bending position of the workpiece W that is currently bending the center of the arc (for example, the intersection of the outlines of the workpiece W in contact with the large bending R after bending, or the center of the bending R formed during bending) Position). The arc portion may be an arc from a position slightly away from the lower plate holder 25 to a position slightly away from the upper plate holder 27. Further, the width between the arcs is slightly shorter than the straight portion of the bending flange in each bending step.

  Refer to FIG. The end face of the workpiece W at the bending side to be angle-measured necessarily exists in a fan-shaped area centered on the bending position. If the shape of the fan-shaped area is appropriately set as described above, the mold, the material presser, and the like exist outside this area. In addition, sides other than the bent side to be measured also exist outside the fan-shaped area. By this method, erroneous measurement can be prevented easily and reliably.

  Please refer to FIG. 17 and FIG. About the shape of a fan-shaped area, it is desirable to be able to set suitably according to bending process conditions. For example, in the case of a material having a large plate thickness T, the fan-shaped outer shape is increased because the radius when bent is large, and in the case of a thin plate thickness T, the fan-shaped inner diameter is decreased because the radius when bent is small. To ensure measurement.

It is a perspective view which shows schematic structure of the whole bending process unit which concerns on this invention. It is a perspective view which shows schematic structure by the side of the bending machine in a bending process unit. It is a side view which shows schematic structure of the whole bending process unit. It is explanatory drawing explaining conveyance and positioning of a workpiece | work. It is explanatory drawing explaining the imaging position of a workpiece | work. It is explanatory drawing explaining the imaging position of a workpiece | work. It is explanatory drawing explaining the imaging position of a workpiece | work. It is a flowchart of the bending process correction | amendment by imaging of a workpiece | work. It is explanatory drawing explaining the data processing of the imaged bending shape image. It is explanatory drawing explaining the data processing of the imaged bending shape image. 1 is a schematic diagram illustrating a schematic configuration of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system. It is explanatory drawing explaining the processing content of an image processing system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bending unit 3 Work table 5 Bending machine 7 Manipulator 9 Safety enclosure 11 Door 35 Frame 37 Lower boulder 39 Upper holder 41A, 41B Post 43 Beam 81 Support member 83 Guide rail 85 Connecting member 87 Imaging machine 89 Guide member 91 Light reflection Member (reflection mirror)
93 Surface light source 95 Control unit W Workpiece

Claims (8)

In a bending system that bends a workpiece with a mold,
An imager that images the shape of a workpiece bent by the mold, a moving device that moves and positions the imager to a predetermined position, a moving device control unit that controls the moving device, and an image of the workpiece A light reflecting member that reflects a predetermined angle toward the image pickup device,
The moving device control means performs control to move the image pickup device according to the position of the imaging location of the workpiece that is installed, the distance from the imaging location of the workpiece to the light reflecting member, and the light reflecting member Keeping the total distance from the imaging device to the proper focal length;
Bending system characterized by   2. The bending system according to claim 1, wherein the light reflecting member that reflects the image of the workpiece at a predetermined angle toward the image pickup device reflects the image of the workpiece from a horizontal direction to a vertical direction. . A surface light source for irradiating the workpiece with light;
The bending work system according to claim 1, wherein the work is disposed between the surface light source and the light reflecting member, and the surface light source irradiates the work with light. In the bending method of bending a workpiece with a mold,
The moving device control means controls the moving device to move and position the image pickup device to a predetermined position, the light reflecting member reflects the image of the workpiece toward the image pickup device at a predetermined angle, and the image pickup device bends the mold. While taking an image of the shape of the workpiece,
The moving device control means performs control to move the image pickup device according to the position of the imaging location of the workpiece that is installed, the distance from the imaging location of the workpiece to the light reflecting member, and the light reflecting member Keeping the total distance from the imaging device to the proper focal length;
Bending method characterized by In a bending system that bends a workpiece with a mold,
An imaging device that images the flange shape of the workpiece bent by the mold, a storage unit that stores a reference flange image in advance, a matching unit that matches the captured flange image, and the reference flange image, and the matching unit Bending angle calculation means for obtaining an angle between the reference flange image and the flange image based on the matching of
Identifying the flange image in a set area, and determining a matching angle with the reference flange image;
Bending system characterized by   The bending system according to claim 5, further comprising an exclusion unit that excludes an image outside the set area.   7. The bending system according to claim 5, wherein the set area has a fan shape. In the bending method of bending a workpiece with a mold,
The image of the flange shape of the workpiece bent by the mold is picked up by the image pickup device, the reference flange image stored in advance in the storage means is taken out, and the matching means matches the picked flange image with the reference flange image. The bending angle calculation means performs a process for obtaining an angle between the reference flange image and the flange image based on the matching of the matching means,
Further, the bending method is characterized in that the flange image in the set region is specified, and a matching angle with the reference flange image is obtained.

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