JP4553420B2 - Plate thickness detection method, plate thickness difference detection method, and plate material bending machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plate thickness detection method, a plate thickness difference detection method, and a plate material bending machine.
[0002]
[Prior art]
As a plate thickness measuring device that measures the plate thickness of a plate-shaped workpiece, the plate thickness measuring device that measures the plate thickness of the workpiece with a micro caliper offline or that measures the plate thickness of the workpiece outside the bending machine It has been known.
[0003]
The above plate thickness measuring apparatus is offline measurement and requires measurement time and input time. Sometimes reading errors and input errors occur. For this reason, mold conditions and workpiece conditions (material, plate thickness) are input in the conventional D value calculation. In this case, since the nominal thickness is used as the plate thickness, there is a problem that if there is a gap with the true plate thickness, the D value is affected and a predetermined angle cannot be obtained.
[0004]
For example, Japanese Patent Publication No. 3-53047, Japanese Patent Laid-Open No. 5-138254, and the like are known as a plate thickness measuring device that measures the plate thickness of a plate-like workpiece in-line.
[0005]
In the former plate thickness measuring device, the plate thickness is detected by detecting the contact between the workpiece and the punch by the applied pressure. In the latter plate thickness measuring device, the plate thickness is detected by detecting the contact between the workpiece and the punch based on the difference between the linear scale value and the command position.
[0006]
[Problems to be solved by the invention]
By the way, the plate thickness measuring apparatus described above determines the torque value due to the generation of force by current or the like, but there is a problem that accurate reading is impossible because the current value includes noise. Further, when the load is small (that is, when the plate thickness is thin or the width is small), the torque change is too small to be read. Further, there is a problem that an error occurs unless the punching speed for reading is extremely slow.
[0007]
An object of the present invention is to provide a plate thickness detection method, a plate thickness difference detection method, and a plate material bending machine capable of accurately detecting the plate thickness of a plate-like workpiece in-line without causing an error. .
[0011]
[Means for Solving the Problems]
  The present invention has been made in view of the above problems,In a plate thickness detection method for detecting a plate thickness of a workpiece in a plate material bending machine equipped with a die and a punch for bending a plate-like workpiece relatively close to and away from each other, when the die supports the workpiece, Laser light oscillated from a laser length measuring device is irradiated almost perpendicularly to the workpiece in the die groove of the die, and the punch comes relatively close to the die and comes into contact with the workpiece slightly. A position detector detects a relative approach position of the punch with respect to the die when a distance measured by the laser length measuring device changes due to displacement, thereby detecting a plate thickness of the workpiece. It is.
[0012]
Therefore, when the die supports the workpiece, the laser light oscillated from the laser length measuring device is irradiated almost perpendicularly to the workpiece in the die groove of the die, and the punch is relative to the die. When the distance measured by the laser length measuring device changes due to close contact with the workpiece and slight displacement, the position of the workpiece relative to the die when the distance measured by the laser length change is detected by the position detector. The plate thickness is detected.
[0013]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position is accurately detected without causing an error.
[0014]
  Also,In a plate thickness detection method for detecting a plate thickness of a workpiece in a plate bending machine equipped with a die and a punch for bending a plate-like workpiece, which are relatively close to and away from each other, a reference for temporary equipment on which the die supports the workpiece A laser length measuring device that irradiates a laser beam perpendicularly to a plane, and the laser length measuring device that irradiates a laser beam from the laser length measuring device to one side surface of the workpiece when the die supports the workpiece; The distance from the workpiece to the irradiation point of the workpiece is measured, the difference between this distance and the distance from the laser length measuring instrument to the reference plane is obtained, and the punch is relatively close to the die and hits the workpiece. A position detector detects a relative approach position of the punch with respect to the die when the laser length measuring device detects a slight displacement in contact with the detected value and the difference between the position detector and the difference. It is characterized in detecting the thickness of the workpiece based.
[0015]
Therefore, when the die supports the workpiece, laser light is irradiated from the laser length measuring device to one side surface of the workpiece, and the distance from the laser length measuring device to the irradiation point of the workpiece is measured. Then, the difference between the measured distance and the distance from the laser length measuring instrument to the reference plane is obtained, and the punch is relatively close to the die and is in contact with the work and slightly displaced. A position detector detects a relative approach position of the punch to the die when the laser length measuring device detects.
The thickness of the workpiece is detected based on the detected value of the position detector and the difference.
[0016]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position is accurately detected without causing an error.
[0017]
  Also,In a plate thickness detecting method for detecting a plate thickness of a plate placed on the upper surface of the die in a plate bending machine equipped with a punch and a die, a laser provided at a predetermined position when the punch is moved relative to the die. The laser beam oscillated from the length measuring device is always irradiated from the tip of the punch to the upper surface of the plate material to measure the distance between the laser length measuring device and the upper surface of the plate material, and the measured value by the laser length measuring device is predetermined. A position detector detects the relative position of the punch with respect to the die when the value matches, and the upper surface position of the dieOn top of the block gauge placed onPunch tip positionAbutPunch position whenWhen,Detection value detected by the position detectorAnd the thickness of the block gaugeBased on the above, the thickness of the plate material is detected.
[0018]
  Therefore, when the punch moves relative to the die, the laser beam emitted from the laser length measuring device provided at a predetermined position is always radiated from the tip of the punch to the upper surface of the plate material, so that the laser length measuring device and the upper surface of the plate material are irradiated. The distance between is measured. Then, the position detector detects the relative position of the punch with respect to the die when the measured value by the laser length measuring device matches a predetermined value. And the upper surface position of the dieTo the block gauge placed onPunch tip positionAbutThe position of the punch and the detected value detected by the position detectorAnd thickness of the block gaugeBased on the above, the plate thickness of the plate material is detected.
[0020]
  Also,In a plate thickness difference detecting method for detecting a plate thickness difference of a plate placed on the upper surface of the die in a plate bending machine equipped with a punch and a die, a laser length measuring device with a block gauge placed on the upper surface of the die Irradiate the bottom surface of the block gauge with the laser light oscillated from the laser, measure the distance from the laser length measuring device to the bottom surface of the block gauge, and then place the first workpiece on the die with the top surface of the die placed on the top surface of the die On the other hand, the movement distance of the punch when the punch comes relatively close to contact with the workpiece and is slightly displaced is detected as a first detection value by the position detector, and then the second workpiece is detected as the upper surface of the die. The position of the punch is detected as a second detection value by the position detector when the punch is relatively close to the die and is in contact with the workpiece and is slightly displaced with the die placed on the die. It is characterized in that to determine the thickness difference of the plate by determining the difference between the second detection value and the first detection values.
[0021]
Accordingly, the distance from the laser length measuring device to the lower surface of the block gauge is measured by irradiating the lower surface of the block gauge with laser light oscillated from the laser length measuring device with the block gauge placed on the upper surface of the die. Next, when the first workpiece is placed on the upper surface of the die, the punch moves relatively close to the die, abuts against the workpiece and is slightly displaced by the position detector. Punch when the first detection value is detected and then the second workpiece is placed on the upper surface of the die and the punch is relatively close to the die and is in contact with the workpiece and slightly displaced Is detected as a second detection value by the position detector. By obtaining the difference between the detected second detection value and the first detection value, the plate thickness difference of the plate material is obtained.
Thus, the plate thickness difference between the plates can be accurately obtained without errors.
[0022]
  Also,In a plate bending machine equipped with a punch and die, a length measuring device for detecting the distance between the lower surface of the measurement position of the plate placed on the die and the upper surface of the die, and the relative approach position of the punch with respect to the die A position detector for detecting, a contact detecting means for detecting that the tip of the punch is in contact with the upper surface of the plate material, a detection value of the position detector when the contact detecting means detects contact, and the length measuring device And a calculating means for calculating the plate thickness of the plate based on the detected value.
[0023]
Therefore, the distance A from the upper surface of the die to the lower surface of the plate material is detected by the length measuring device in a state where the plate material is placed on the die. Next, a distance B from the upper surface of the die to the punch when the punch comes into contact with the upper surface of the plate material is detected by a position detector. The detected distances A and B are taken into the calculation means, and the thickness of the plate material is calculated by the calculation means.
[0024]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position is accurately detected without causing an error.
[0025]
  Also,The plate material bending machine includes a punch and a die for bending a plate-shaped workpiece, a driving device for moving the punch relatively close to and away from the die, and a relative approach position of the punch to the die. A position detector for detection, a laser length measuring device for irradiating the workpiece with laser light for length measurement in the die groove of the die, and a minute change in the detected value of the laser length measuring device when the punch is relatively close to the die Reading means for reading the detection value of the position detector as the plate thickness of the workpiece when detecting.
[0026]
Therefore, by driving the driving device, the punch is moved closer to and away from the die, and the position of the punch relative to the die is detected by the position detector. When the workpiece is irradiated with laser light for length measurement in the die groove of the die from the laser length measuring device, and the minute change in the detection value of the laser length measuring device is detected when the punch is relatively approached to the die, the position is The detection value of the detector is read as the thickness of the workpiece by the reading means.
[0027]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position is accurately detected without causing an error.
[0028]
  Also,The plate material bending machine includes a punch and a die for bending a plate-shaped workpiece, a driving device for moving the punch relatively close to and away from the die, and a relative approach position of the punch to the die. A position detector for detection, a laser length measuring device for irradiating a workpiece with laser light for length measurement in the die groove of the die, and a virtual reference plane on which the die supports the workpiece and the laser length measuring device. And a second memory for storing a distance measured from the laser length measuring device to one side of the workpiece when the die supports the workpiece and irradiates one side of the workpiece with laser light. And the detection value of the position detector is detected when the detection value of the laser length measuring device changes minutely when the punch moves relative to the die, and the detection value, the reference distance, and the measurement value are detected. Long distance and And calculating means for calculating the thickness of the workpiece based is to characterized in that it comprises a.
[0029]
Therefore, by driving the driving device, the punch is moved closer to and away from the die, and the position of the punch relative to the die is detected by the position detector. A laser beam for length measurement is irradiated from the laser length measuring instrument to the workpiece in the die groove of the die, and a reference distance between a virtual reference plane on which the die supports the workpiece and the laser length measuring instrument is first. The distance measured from the laser length measuring device to one side surface of the workpiece when the die supports the workpiece and irradiates one side surface of the workpiece with laser light is stored in the second memory. Further, when a minute change in the detected value of the laser length measuring device is detected when the punch is relatively approached to the die, the detected value of the position detector is detected. Based on the detected value, the reference distance, and the length measurement distance, the thickness of the workpiece is calculated by the calculation means.
[0030]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position is accurately detected without causing an error.
[0031]
  In addition,In the plate material bending machine, the die includes a reflecting surface that reflects the laser light emitted from the laser length measuring device in the direction of the workpiece in the die groove, and a slit or hole through which the laser light can pass. To do.
[0032]
Therefore, since the die is provided with a reflecting surface for reflecting the laser beam irradiated from the laser length measuring device in the direction of the workpiece in the die groove and a slit or hole through which the laser beam can be transmitted, the plate thickness is further increased. It is detected accurately.
[0033]
  Also,The plate material bending machine is a plate material bending machine equipped with a punch and a die, and a position detector for detecting a relative approach position of the punch to the die, and a length measurement from the tip of the punch to the upper surface of the plate material on the die. A laser length measuring device for irradiating a laser beam for the purpose, and a calculation means for reading the detected value of the positioner as a plate thickness when the measured value of the laser length measuring device matches a predetermined value. It is characterized by this.
[0034]
Therefore, in a state where the plate-like plate material is placed on the die, the punch with respect to the die is moved relatively, and the approach position at that time is detected by the position detector. A laser beam for length measurement is irradiated from the tip of the punch to the upper surface of the plate material on the die from the laser length measuring device. And the detected value of the said position device when the measured value measured with the laser length measuring device corresponds with a predetermined value is read as plate | board thickness by a calculating means.
[0035]
Thus, the true plate thickness at the bending position is accurately detected without causing an error.
[0036]
  Also,The plate material bending machine is a plate material bending machine equipped with a punch and a die. A block gauge used in a state of being placed on the upper surface of the die and a lower surface of the block gauge in which laser light is placed on the upper surface of the die or the first sheet, A laser measuring instrument that measures the distance to the lower surface of the block gauge or the lower surface of the first and second workpieces by irradiating the lower surface of the first workpiece and the punch relatively close to the die Then, a position detector that detects the movement distance of the punch when it is in contact with the workpiece and slightly displaced, and a difference in plate thickness of the plate based on the first detection value and the second detection value detected by the position detector And a calculating means for obtaining.
[0037]
Accordingly, the distance from the laser length measuring device to the lower surface of the block gauge is measured by irradiating the lower surface of the block gauge with laser light oscillated from the laser length measuring device with the block gauge placed on the upper surface of the die. Next, when the first workpiece is placed on the upper surface of the die, the punch moves relatively close to the die, abuts against the workpiece and is slightly displaced by the position detector. Punch when the first detection value is detected and then the second workpiece is placed on the upper surface of the die and the punch is relatively close to the die and is in contact with the workpiece and slightly displaced Is detected as a second detection value by the position detector. The detected second detection value and the first detection value are taken into the calculation means, and the calculation means obtains the difference between the second detection value and the first detection value, thereby obtaining the plate thickness difference of the plate material.
[0038]
Thus, the plate thickness difference between the plates can be accurately obtained without errors.
[0039]
  In addition,The plate material bending machine includes a correction device that corrects the difference in plate thickness calculated by the calculation means.
[0040]
Therefore, the plate thickness difference calculated by the calculation means is taken into the correction device, and the plate thickness of the plate material is corrected, so that bending with an accurate bending angle is performed.
[0041]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0042]
Referring to FIG. 1, FIG. 2 and FIG. 3, a press brake 1 as a plate material bending machine includes side frames 3L and 3R which are erected, and the side frames 3L and 3R have a substantially central portion. It has a notch G. In addition, an upper table 7 as a ram for mounting the punch P via a plurality of intermediate plates 5 is provided at the lower front portion in front of the upper portions of the side frames 3L, 3R.
[0043]
Left and right ball screw units 9L and 9R, which are ram driving means for moving the upper table 7 up and down, are provided on the upper front surfaces of the side frames 3L and 3R. In the ball screw units 9L and 9R, a ball screw (not shown) is rotationally driven by the drive motor 11 to move the upper table 7 up and down.
[0044]
Meanwhile, front and rear (left and right in FIGS. 2 and 3) support plates 13F and 13R are provided on the lower front surfaces of the side frames 3L and 3R. It is sandwiched between the upper portions of the support plates 13F and 13R. The left and right ends of the lower table 15 are supported by fulcrum pins 17L and 17R that penetrate through the support plates 13F and 13R and are fixed to the side frames 3L and 3R.
[0045]
Accordingly, the left and right end portions of the lower table 15 are fixed in the vertical direction with respect to the side frames 3L and 3R by the fulcrum pins 17L and 17R, but a slight vertical deformation is possible at the central portion.
[0046]
Further, a crowning means 19 is provided for lifting the central portion of the lower table 15 with the left and right fulcrum pins 17L and 17R as fulcrums so as to contact the lower side of the lower table 15 at the central portions of the support plates 13F and 13R. It has been. Further, a control device 21 for controlling the drive motor 11 and the like is provided on the left side of the left side frame 3L in FIG.
[0047]
A back gauge device 23 for adjusting the bending position of the workpiece W to the positions of the punch P and the die D is provided at the position of the notch G of the side frames 3L, 3R. In this back gauge device 23, a plurality of abutments 25 that abut the workpiece W are provided on the stretch 27, and the stretch 27 is moved and positioned in the L-axis direction (front-rear direction) by the link mechanism 31 by the L-axis motor 29. It has become. Further, by driving the Z-axis motor 33, the abutment 25 is moved in the Z-axis direction (vertical direction) via the link mechanism 31. Further, by driving the Y-axis motor 35, the abutment 25 is moved in the Y-axis direction (left-right direction) by a rack and pinion drive mechanism, for example.
[0048]
With the above configuration, the abutment 25 of the back gauge device 23 is moved in the L-axis, Y-axis, and Z-axis directions to be positioned at desired positions, and the workpiece W is abutted against the abutment 25. Next, the workpiece W is bent by the cooperation of the punch P and the die D.
[0049]
Referring to FIG. 2, detection plates 37 are attached to the outer surfaces of the side frames 3 </ b> L and 3 </ b> R in a state where the notch G is avoided from the lower side to the upper side of the notch G. The detection plate 37 is fixed to the side frames 3L and 3R by bolts 39 at the lower part, and is pressed by the bolts 43 at the upper part by a loose hole 41 so as to be movable relative to the side frames 3L and 3R. Therefore, even if the side frames 3L and 3R are deformed in the direction of the arrow in FIG. 2 and the notch G is opened or closed, the deformation of the detection plate 37 is not affected.
[0050]
2 and 4, a linear guide 45 is attached to the upper front end surface (right end surface in FIG. 2) of the detection plate 37 in the vertical direction. In the vicinity of the upper end portion of the linear guide 45, for example, a magnetic read sensor 47 as a position detector is attached forward through a bracket 49.
[0051]
A bracket 51 is attached to the back surface of the upper table 7, and an arm 53 is attached to the tip of the bracket 51 so as to extend upward. A dog mounting bracket 57 is attached to a position at the tip of the arm 53 that can face the magnetic read sensor 47 via a bearing 55 so that the direction of the dog can be changed. A pair of guide blocks 59 that are movable along is attached. A dog 61 is attached to the side of the upper guide block 59 in the dog attachment bracket 57.
[0052]
Therefore, the magnetic reading sensor 47 detects the position due to the vertical movement of the upper table 7, that is, the position when the punch P is moved.
[0053]
As shown in FIG. 5, a plurality of slits 63 are formed at appropriate positions in the left-right direction of the die D so as to communicate with the die groove DV. Instead of the slit 63, a hole may be used. In this slit 63, as shown in FIG. 6, there is provided a reflection mirror 65 that constitutes a reflection surface that is inclined approximately 45 degrees obliquely upward to the right. Further, as shown in FIG. 6, a laser length measuring device 67 is provided at the abutment 25 of the back gauge device 23.
[0054]
With the above configuration, the laser length measuring device 67 is moved in the L-axis, Y-axis, and Z-axis directions and positioned at a desired position. In addition, the laser beam LB oscillated from the laser length measuring device 67 is reflected by the reflecting mirror 65 and then passes through the slit 63 to be irradiated onto the side surface of the workpiece W. The irradiated laser beam LB is returned to the laser length measuring device 67 as return light, and the distance from the laser length measuring device 67 to the side surface of the workpiece W is detected. The reference position, which is the tip position of the laser length measuring device 67 in the Y-axis direction, is previously positioned at a desired position by the Y-axis motor 29.
Further, the distance to the both side surfaces of the workpiece W is detected by moving and positioning the laser length measuring device 67 in the Z-axis direction by the Z-axis motor 33. Therefore, the plate thickness of the workpiece W is accurately calculated using the detected distances to both side surfaces of the workpiece W.
[0055]
As an example of contact detection means for detecting that the tip of the punch P is in contact with the upper surface of the workpiece W as a plate material, the laser length measuring device 67 measures the length from the laser length measuring device 67 to the side surface of the workpiece W. After the distance is detected, the contact with the upper surface of the workpiece W is detected by a slight change in the measurement distance.
[0056]
As shown in FIG. 7, the control device 21 is provided with a CPU 69, to which an input means 71 such as a keyboard for inputting various data is connected, and various data are inputted. Display means 73 such as a CRT for displaying is connected. The X-axis motor 35 and the Y-axis motor 29 are provided with encoders 75 and 77 as position detectors, respectively, and are connected to the CPU 69. The drive motor 11 and the Z-axis motor 33 are also connected to the CPU 69.
[0057]
The CPU 69 is connected to a laser length measuring device 67 (contact detection means) and a magnetic reading sensor 47 as a position detector.
[0058]
The reference distance between the virtual reference plane on which the die D detected by the laser length measuring device 67 supports the workpiece W and the laser length measuring device 67 and the die D supports the workpiece W, and the laser beam is applied to one side of the workpiece W. In the first and second memories 79 and 81 and the first and second memories 79 and 81 for storing the distance measured from the laser length measuring device 67 to one side surface of the workpiece W when LB is irradiated. Calculation means 83 for calculating the plate thickness based on the stored measurement distance is connected to the CPU 43.
[0059]
The plate thickness algorithm calculated by the calculation means 83 will be described. As shown in FIGS. 8A and 8B, a reflection mirror 65 constituting a reflection surface inclined at approximately 45 degrees is provided in the slit 63 communicating with the die groove DV of the die D.
[0060]
With the above configuration, for example, the block gauge BG is placed on the upper surface of the die D, that is, the virtual reference plane in FIG. In this state, the laser beam LB oscillated from the laser length measuring device 67 is reflected by the reflecting mirror 65 and then irradiated to the point A1 on the lower surface of the block gauge. The laser beam LB irradiated to the point A1 is received by the laser length measuring device 67 as return light, and the length measuring distance from the laser length measuring device 67 to the point A1 which is the lower surface of the block gauge BG, that is, the upper surface of the die D. L0 is measured.
[0061]
Next, the block gauge BG is removed, and the workpiece W as a plate material is supported on the upper surface of the die D while being warped upward, for example, as shown in FIG. 8B. In this state, the laser beam LB oscillated from the laser length measuring device 67 is reflected by the reflecting mirror 65 and then irradiated to the point A2 on the lower surface of one side surface of the workpiece W. Then, the laser light LB irradiated to the point A2 is received as a return light by the laser length measuring device 67, and the length measurement distance L1 from the laser length measuring device 67 to the point A2 on the lower surface of the workpiece W is measured. Accordingly, the distance from the point A1 on the upper surface of the die D to the point A2 on the lower surface of the workpiece W is detected by A = L1-L0 and stored in the first memory 79.
[0062]
Next, the drive motor 11 is driven to lower the punch P from a distance P0 from the upper surface of the die D to the tip of the punch P, and the punch P moves downward as indicated by a two-dot chain line, and the punch P is moved to the upper surface of the workpiece W. The magnetic reading sensor 47 detects the movement distance P1 of the punch P when the contact detection means detects that the tip of the contact has come into contact. As a result, the distance from the point A3 where the tip of the punch P abuts on the upper surface of the workpiece W to the upper surface of the die D is detected by B = P0−P1 and stored in the second memory 81.
[0063]
The distance A stored in the first memory 79 and the distance B stored in the second memory 81 are taken into the calculation means 83, and the calculation means 83 calculates the thickness t at t = B−A. It can be shown.
[0064]
Thus, even if the workpiece W as a plate-like plate material is warped, since the upper and lower surfaces of the workpiece W are detected, the true plate thickness at the bending position is accurately detected without causing an error. be able to.
[0065]
Moreover, the reflecting mirror 65 that forms a reflecting surface for reflecting the laser beam LB irradiated to the die D from the laser length measuring device 67 in the direction of the workpiece W in the die groove DV and the slit 63 through which the laser beam LB can be transmitted. Since the hole is provided, the plate thickness can be detected more accurately.
[0066]
In the above-described embodiment, even if the upper surface of the die D is not a flat surface, it can be handled even if it has an uneven shape.
[0067]
FIGS. 9A and 9B show another embodiment in place of FIGS. 8A and 8B. In FIGS. 9A and 9B, the same components as those in FIGS. 8A and 8B are denoted by the same reference numerals, and redundant description will be omitted.
[0068]
That is, a laser length measuring device 67 as an example of a length measuring device is provided in the slit 63 communicating with the die groove DV of the die D in FIGS. Then, the laser beam LB oscillated from the laser length measuring device 67 is irradiated toward the block gauge BG or the workpiece W placed on the upper surface of the die D, and the punch P is lowered so that the punch P is applied to the workpiece W. By bringing the tip into contact, the calculation process is performed in the manner described with reference to FIGS.
[0069]
Thus, even if the workpiece W as a plate-like plate material is warped, the true plate thickness at the bending position is accurately detected without causing an error because the upper and lower surfaces of the workpiece W are detected. be able to.
[0070]
Although the laser length measuring device 67 has been described as an example of the length measuring device, other known length measuring devices other than the laser length measuring device 67 may be used. Further, even if the upper surface of the die D is not flat, it can be handled even if it has an uneven shape.
[0071]
8 (A), 8 (B) and 9 (A), 9 (B), the description is based on the workpiece W having a shape that is warped downward or upward, but in the case of a workpiece W having a flat shape. Does not measure A with the above-described formula t = B−A, and sets A = 0, t = B, that is, the position when the tip of the punch P is brought into contact with the workpiece W by lowering the punch P. It may be detected by the magnetic reading sensor 47 as a detector, and the detected value is read as the plate thickness of the workpiece W by the reading means.
[0072]
FIGS. 10A and 10B show another embodiment. In FIGS. 10A and 10B, the same components as those in FIGS. 8A and 8B are denoted by the same reference numerals, and redundant description will be omitted.
[0073]
That is, in FIGS. 10A and 10B, a slit 63 is provided in the punch P, and a reflecting mirror 65 constituting a reflecting surface inclined at approximately 45 degrees is provided in the slit 63. A laser length measuring device 67 is attached to the side surface of the upper table 7.
[0074]
With the above configuration, as shown in FIG. 10A, for example, a block gauge BG whose thickness C0 is known in advance is placed on the upper surface of the die D. In this state, the drive motor 11 is driven to lower the punch P. Then, the laser beam LB oscillated from the laser length measuring device 67 is always irradiated to the upper surface of the block gauge BG placed on the upper surface of the die D, and the distance between the laser length measuring device 67 and the upper surface of the block gauge BG is measured. Then, the magnetic reading sensor 47 detects the descending amount of the punch P when the measured value by the laser length measuring device 67 coincides with a predetermined value, that is, the position in contact with the upper surface of the block gauge BG, and the detected value is C1. To do.
[0075]
Next, the block gauge BG is removed from the upper surface of the die D, and a flat work W is placed as shown in FIG. In this state, the drive motor 11 is driven to lower the punch P. Then, the laser beam LB oscillated from the laser length measuring device 67 is always applied to the upper surface of the work W placed on the upper surface of the die D to measure the distance between the laser length measuring device 67 and the upper surface of the work W, When the measured value by the laser length measuring device 67 coincides with a predetermined value, that is, the position in contact with the upper surface of the workpiece W, the downward movement amount of the punch P is detected by the magnetic reading sensor 47, and the detected value is C2.
[0076]
As a result, the thickness t can be obtained by calculating t = (C1 + C0) −C2 by the calculation means 83.
[0077]
Thus, the true plate thickness at the bending position can be accurately detected without causing an error.
[0078]
In FIGS. 10A and 10B, the laser length measuring device 67 is not attached to the side surface of the upper table 7 but can be fixedly provided at another place.
[0079]
10 (A) and 10 (B), even if the reflecting mirror 65 is removed from the slit 63 and the laser length measuring device 67 is provided in the slit 63, it has been explained with reference to FIGS. 10 (A) and 10 (B). The same operation and effect are exhibited.
[0080]
FIGS. 11A and 11B and FIGS. 12A and 12B show an embodiment for obtaining a plate thickness difference of the workpiece W. FIG. In FIGS. 11A and 11B and FIGS. 12A and 12B, the same components as those in FIGS. 8A and 8B are denoted by the same reference numerals, and redundant description is omitted. The differences will be described.
[0081]
In FIG. 11A, the magnetic reading sensor 47 detects when the driving motor 11 is driven to lower the punch P and the tip of the punch P comes into contact with the workpiece W placed on the upper surface of the die D. Let the detected value be LS0. The measured value by the laser length measuring device 67 at this time is L0. Further, as shown in FIG. 11B, the punch P is lowered to deform the work W downward. The measured value L1 by the laser length measuring device 67 when the slight deformation amount d stored or input in the control device in advance is reached, and the detected value detected by the magnetic reading sensor 47 at that time is denoted by LS1.
[0082]
Next, as shown in FIG. 12A, for example, a block gauge BG is placed on the upper surface of the die D, that is, the virtual reference plane. In this state, the laser beam LB oscillated from the laser length measuring device 67 is reflected by the reflecting mirror 65 and then irradiated to the lower surface of the block gauge. Then, the laser beam LB irradiated on the lower surface of the block gauge is received by the laser length measuring device 67 as return light, and the length measurement distance L0 from the laser length measuring device 67 to the lower surface of the block gauge BG is measured.
[0083]
Next, the block gauge BG is removed, and the first work W1 as a plate material is supported on the upper surface of the die D in a flat state, for example, as shown in FIG. In this state, the punch P is lowered and a bending operation is performed on the workpiece W1, and the detected value detected by the magnetic reading sensor 47 when the deformation amount d of the workpiece W1 is reached is denoted by LS1.
[0084]
Next, the first workpiece W1 is removed, and the second workpiece W2 is supported on the upper surface of the die D in a flat state, for example, as shown in FIG. In this state, the punch P is lowered to perform a bending operation on the workpiece W2, and a detected value detected by the magnetic reading sensor 47 when the deformation amount d of the workpiece W2 is reached is defined as LS1 '.
[0085]
As a result, the detected value LS1 and the detected value LS1 'are taken into the calculating means 83, and the calculating means 83 can calculate the plate thickness difference by (LS1'-LS1). This value is fed back and corrected to the correction device of the control device to increase or decrease the stroke of the punch P and bend the workpiece W to obtain a bent product having an accurate bending angle.
[0086]
Thus, it is possible to accurately detect the plate thickness difference without errors.
[0087]
Alternatively, as another measurement method, for example, a block gauge BG is placed on the upper surface of the die D, that is, the virtual reference plane, as shown in FIG. In this state, the laser beam LB oscillated from the laser length measuring device 67 is reflected by the reflecting mirror 65 and then irradiated to the lower surface of the block gauge. Then, the laser beam LB irradiated on the lower surface of the block gauge is received by the laser length measuring device 67 as return light, and the length measurement distance L0 from the laser length measuring device 67 to the lower surface of the block gauge BG is measured.
[0088]
Next, the measured values L1 and L2 are read by the laser length measuring device 67 when the deformation amount of the workpiece W1 reaches the deformation amount when the first workpiece W1 is d and d ', respectively, and is shown in FIG. As shown, the intersection C can be obtained from the equation Y = 0 and Y = aX + b. That is, the intersection C corresponds to LS0. As a result, a = (L1−L2) ÷ (LS2−LS1) and b = (L1−L2) ÷ (LS2−LS1) × LS2 can be obtained.
[0089]
The same operation as that performed on the first workpiece W1 is performed on the second and subsequent workpieces W to obtain the intersection C '. The intersection point C 'corresponds to LS0'. As a result, (LS0'-LS0) is obtained, fed back to the correction device of the control device, corrected, and the stroke of the punch P is increased or decreased to bend the workpiece W to obtain a bent product having an accurate folding angle. Obtainable.
[0090]
Thus, it is possible to accurately detect the plate thickness difference without errors.
[0091]
In addition, this invention is not limited to embodiment of invention mentioned above, It can implement in another aspect by making an appropriate change. In the above-described embodiment, the example in which the punch P is moved up and down has been described. However, the die D may be moved up and down.
[0092]
【The invention's effect】
  As will be understood from the description of the embodiment of the invention as described above,According to the present invention, when the die supports the workpiece, the laser beam oscillated from the laser length measuring device is irradiated substantially perpendicularly to the workpiece in the die groove of the die, The position detector detects the relative approach position of the punch with respect to the die when the distance measured by the laser length measuring device changes due to the punch approaching relatively close to the workpiece and moving slightly. The thickness of the workpiece can be detected.
[0095]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0096]
  Also bookAccording to the invention, when the die supports the workpiece, the laser length measuring device irradiates the side surface of the workpiece with laser light, and the distance from the laser length measuring device to the irradiation point of the workpiece is measured. Then, the difference between the measured distance and the distance from the laser length measuring instrument to the reference plane is obtained, and the punch is relatively close to the die and is in contact with the work and slightly displaced. A position detector detects a relative approach position of the punch to the die when the laser length measuring device detects. The thickness of the workpiece can be detected based on the detected value of the position detector and the difference.
[0097]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0098]
  Also bookAccording to the invention, when the punch moves relative to the die, the laser length measuring device always irradiates the laser beam emitted from the laser length measuring device provided at a predetermined position from the tip of the punch to the upper surface of the plate. The distance between the top surface of the plate is measured. Then, the position detector detects the relative position of the punch with respect to the die when the measured value by the laser length measuring device matches a predetermined value. And the upper surface position of the dieTo the block gauge placed onPunch tip positionAbutThe position of the punch and the detected value detected by the position detectorAnd thickness of the block gaugeBased on the above, it is possible to detect the plate thickness of the plate member.
[0099]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0100]
  Also bookAccording to the invention, the distance from the laser length measuring device to the lower surface of the block gauge is measured by irradiating the lower surface of the block gauge with laser light oscillated from the laser length measuring device with the block gauge placed on the upper surface of the die. The Next, when the first workpiece is placed on the upper surface of the die, the punch moves relatively close to the die, abuts against the workpiece and is slightly displaced by the position detector. Punch when the first detection value is detected and then the second workpiece is placed on the upper surface of the die and the punch is relatively close to the die and is in contact with the workpiece and slightly displaced Is detected as a second detection value by the position detector. By obtaining the difference between the detected second detection value and the first detection value, the plate thickness difference of the plate material can be obtained.
[0101]
Thus, the plate thickness difference between the plate members can be accurately obtained without errors.
[0102]
  Also bookAccording to the invention, the distance A from the upper surface of the die to the lower surface of the plate material is detected by the length measuring device in a state where the plate material is placed on the die. Next, a distance B from the upper surface of the die to the punch when the punch comes into contact with the upper surface of the plate material is detected by a position detector. The detected distances A and B can be taken into the calculation means, and the thickness of the plate material can be calculated by the calculation means.
[0103]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0104]
  Also bookAccording to the invention, by driving the driving device, the punch is moved relatively close to and away from the die, and the position of the punch relative to the die is detected by the position detector. When the workpiece is irradiated with laser light for length measurement in the die groove of the die from the laser length measuring device, and the minute change in the detection value of the laser length measuring device is detected when the punch is relatively approached to the die, the position is The detection value of the detector can be read as the thickness of the workpiece by the reading means.
[0105]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0106]
  Also bookAccording to the invention, by driving the driving device, the punch is moved relatively close to and away from the die, and the position of the punch relative to the die is detected by the position detector. A laser beam for length measurement is irradiated from the laser length measuring instrument to the workpiece in the die groove of the die, and a reference distance between a virtual reference plane on which the die supports the workpiece and the laser length measuring instrument is first. The distance measured from the laser length measuring device to one side surface of the workpiece when the die supports the workpiece and irradiates one side surface of the workpiece with laser light is stored in the second memory. Further, when a minute change in the detected value of the laser length measuring device is detected when the punch is relatively approached to the die, the detected value of the position detector is detected. Based on the detected value, the reference distance, and the measurement distance, the thickness of the workpiece can be calculated by the calculation means.
[0107]
Thus, even if the plate-like plate material is warped, the upper and lower surfaces of the plate material are detected, so that the true plate thickness at the bending position can be accurately detected without causing an error.
[0108]
  Also bookAccording to the invention, since the die is provided with the reflecting surface for reflecting the laser beam irradiated from the laser length measuring device toward the workpiece in the die groove and the slit or the hole through which the laser beam can be transmitted. The plate thickness can be detected accurately.
[0109]
  Also bookAccording to the invention, with the plate-like plate material placed on the die, the punch with respect to the die is moved relatively, and the approach position at that time is detected by the position detector. A laser beam for length measurement is irradiated from the tip of the punch to the upper surface of the plate material on the die from the laser length measuring device. And the detected value of the said position device when the measured value measured with the laser length measuring device corresponds with a predetermined value can be read as plate | board thickness by an arithmetic processing part.
[0110]
Thus, the true plate thickness at the bending position can be accurately detected without causing an error.
[0111]
  Also bookAccording to the invention, the distance from the laser length measuring device to the lower surface of the block gauge is measured by irradiating the lower surface of the block gauge with laser light oscillated from the laser length measuring device with the block gauge placed on the upper surface of the die. The Next, when the first workpiece is placed on the upper surface of the die, the punch moves relatively close to the die, abuts against the workpiece and is slightly displaced by the position detector. Punch when the first detection value is detected and then the second workpiece is placed on the upper surface of the die and the punch is relatively close to the die and is in contact with the workpiece and slightly displaced Is detected as a second detection value by the position detector. The detected second detection value and the first detection value are taken into the calculation means, and the calculation means obtains the difference between the second detection value and the first detection value, thereby obtaining the plate thickness difference of the plate material. it can.
[0112]
Thus, the plate thickness difference between the plate members can be accurately obtained without errors.
[0113]
  Also bookAccording to the invention, the plate thickness difference calculated by the calculation means is taken into the correction device and the plate thickness of the plate material is corrected, so that bending with an accurate bending angle can be performed.
[Brief description of the drawings]
FIG. 1 is a front view of a press brake as a bending machine according to the present invention.
FIG. 2 is a left side view in FIG.
FIG. 3 is a right side view in FIG. 1;
4 is an enlarged view of an IV arrow portion in FIG. 2. FIG.
FIG. 5 is a front view of a die.
6 is an enlarged view of a V arrow portion in FIG. 2. FIG.
FIG. 7 is a configuration block diagram of a control device.
FIGS. 8A and 8B are explanatory diagrams for detecting the thickness of a workpiece. FIGS.
FIGS. 9A and 9B are explanatory diagrams for detecting the thickness of a workpiece. FIGS.
FIGS. 10A and 10B are explanatory views for detecting the thickness of a workpiece. FIGS.
FIGS. 11A and 11B are explanatory diagrams for detecting a plate thickness difference of a workpiece. FIGS.
FIGS. 12A and 12B are explanatory diagrams for detecting a plate thickness difference of a workpiece. FIGS.
FIG. 13 is an explanatory diagram for detecting a plate thickness difference of a workpiece.
[Explanation of symbols]
1 Press brake (bending machine)
7 Upper table
11 Drive motor
15 Lower table
23 Back gauge device
37 slits
47 Magnetic type reading sensor (position detector)
61 Dog
63 Reflective mirror (reflective surface)
67 Laser length measuring instrument
79 First memory
81 second memory
83 Calculation means
P punch
D die
W Work
DV die groove
LB laser light

Claims (11)

  In a plate thickness detection method for detecting a plate thickness of a workpiece in a plate material bending machine equipped with a die and a punch for bending a plate-like workpiece relatively close to and away from each other, when the die supports the workpiece, Laser light oscillated from a laser length measuring device is irradiated almost perpendicularly to the workpiece in the die groove of the die, and the punch comes relatively close to the die and comes into contact with the workpiece slightly. A plate that detects a plate thickness of a workpiece by detecting a relative approaching position of the punch to the die when the measuring distance by the laser length measuring device is changed by displacement. Thickness detection method.   In a plate thickness detection method for detecting a plate thickness of a workpiece in a plate bending machine equipped with a die and a punch for bending a plate-like workpiece, which are relatively close to and away from each other, a reference for temporary equipment on which the die supports the workpiece A laser length measuring device that irradiates a laser beam perpendicularly to a plane, and the laser length measuring device that irradiates a laser beam from the laser length measuring device to one side surface of the workpiece when the die supports the workpiece; The distance from the workpiece to the irradiation point of the workpiece is measured, the difference between this distance and the distance from the laser length measuring instrument to the reference plane is obtained, and the punch is relatively close to the die and hits the workpiece. A position detector detects a relative approach position of the punch with respect to the die when the laser length measuring device detects a slight displacement in contact with the detected value and the difference between the position detector and the difference. Plate thickness detection method characterized by detecting the thickness of the workpiece based. In a plate thickness detecting method for detecting a plate thickness of a plate placed on the upper surface of the die in a plate bending machine equipped with a punch and a die, a laser provided at a predetermined position when the punch moves relative to the die. The distance between the laser length measuring instrument and the top surface of the plate is measured by constantly irradiating laser light emitted from the length measuring device from the tip of the punch to the top surface of the plate material. the relative position of the punch relative to the die when matches the value detected by the position detector, the position of the punch when the tip position of the punch has contact to the top surface of the block gauges placed on the upper surface position of the die a detection value detected by the position detector, the thickness detecting method and detecting the thickness of the plate material based on the thickness of the block gauge.   In a plate thickness difference detecting method for detecting a plate thickness difference of a plate placed on the upper surface of the die in a plate bending machine equipped with a punch and a die, a laser length measuring device with a block gauge placed on the upper surface of the die Irradiate the bottom surface of the block gauge with the laser light oscillated from the laser, measure the distance from the laser length measuring device to the bottom surface of the block gauge, and then place the first workpiece on the die with the top surface of the die placed on the top surface of the die On the other hand, the first detection value is detected by the position detector for the movement distance of the punch when the punch comes relatively close to contact with the workpiece and is slightly displaced, and then the second workpiece is placed on the upper surface of the die. The second detection value is detected by the position detector of the movement distance of the punch when the punch is relatively close to the die and is in contact with the work and is slightly displaced with the die placed on the die. Plate thickness difference detection method characterized by determining the thickness difference of the plate by determining the second detection value and the difference between the first detection value.   In a plate bending machine equipped with a punch and die, a length measuring device for detecting the distance between the lower surface of the measurement position of the plate placed on the die and the upper surface of the die, and the relative approach position of the punch with respect to the die A position detector to detect, contact detection means for detecting that the tip of the punch has contacted the upper surface of the plate material, a detection value of the position detector when the contact detection means detects contact, and the length measuring device And a calculating means for calculating the plate thickness of the plate material based on the above.   Punch and die for bending plate-shaped workpiece, drive device for moving the punch relatively close to and away from the die, and position detector for detecting the relative approach position of the punch with respect to the die A laser length measuring device that irradiates a workpiece with laser light for length measurement in the die groove of the die, and when a minute change in the detection value of the laser length measuring device is detected when the punch is relatively close to the die And a reading means for reading the detected value of the position detector as the plate thickness of the workpiece.   Punch and die for bending plate-shaped workpiece, drive device for moving the punch relatively close to and away from the die, and position detector for detecting the relative approach position of the punch with respect to the die In the die groove of the die, a laser length measuring device for irradiating the workpiece with laser light for length measurement, and a reference distance between a virtual reference plane on which the die supports the workpiece and the laser length measuring device are stored. A first memory; a second memory for storing a distance measured from the laser length measuring instrument to one side of the workpiece when the die supports the workpiece and irradiates one side of the workpiece with laser light; and The detected value of the position detector is detected when the detected value of the laser length measuring device changes minutely during the relative movement of the punch with respect to the die, and based on the detected value, the reference distance, and the measured distance. Workpiece thickness Sheet bending machine and characterized in that it comprises calculating means for calculating, the. 8. The plate according to claim 7, wherein the die includes a surface that reflects the laser light emitted from the laser length measuring device in the direction of the workpiece in the die groove and a slit or a hole through which the laser light can pass. Bending machine.   In a plate bending machine equipped with a punch and a die, a position detector that detects the relative approach position of the punch with respect to the die, and a laser beam for length measurement from the tip of the punch to the upper surface of the plate on the die A plate material comprising: a laser length measuring device for performing the measurement; and a calculation means for reading a detected value of the positioner as a plate thickness when a measured value of the laser length measuring device matches a predetermined value. Bending machine.   In a plate bending machine equipped with a punch and a die, a block gauge used in a state of being placed on the upper surface of the die and a lower surface of the block gauge on which the laser beam is placed on the upper surface of the die, or the lower surface of the first and second workpieces A laser length measuring instrument that measures the distance to the lower surface of the block gauge or the lower surface of the first and second workpieces, and the punch comes in contact with the workpiece relative to the die. A position detector that detects the movement distance of the punch when it is slightly displaced, a first detection value detected by the position detector, a calculation means for obtaining a plate thickness difference of the plate material based on the second detection value; A plate material bending machine characterized by comprising: 11. The plate material bending machine according to claim 10 , further comprising a correction device that corrects the plate thickness difference calculated by the calculation means.

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