JP2818428B2 - Bending equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a bending apparatus.

(Prior Art) A bending device is for bending a work interposed between a punch or a die into a predetermined shape by bringing one of the punches or the die closer to the other. Since the final positioning position has a significant effect on the product shape, it must be accurately determined.

Conventionally, the final bending position is determined manually or automatically.

That is, in the conventional manual determination of the final bending position, a bending position is set in advance using test bending or previous processing data, and correction is appropriately performed according to the actual bending.

Further, in the conventional automatic final bending position determination, the bending state is detected by, for example, a bending angle detecting device provided on the die or a visual sensor provided on the side surface of the work, and the target bending angle is set in advance according to the product shape in advance. There is an example in which feedback control is performed so as to obtain a bending angle.

(Problems to be Solved by the Invention) However, although the above-described automatic final bending angle determination method has an advantage that the bending can be automatically performed by feedback control, there is a problem in the bending angle detection method. There was a problem that it was difficult to put it to practical use.

That is, a conventional bending angle detecting device provided on a punch or a die is provided with, for example, a capacitance-type distance sensor for detecting a distance to a work in a V-groove of the die. Since the method detects angles, there is a problem in that an error occurs in the detected distance according to the surface condition of the work, and that the detection devices must be attached to all dies. Furthermore, the mounting accuracy must be considerably improved in order to obtain good accuracy.

In addition, in the conventional method of detecting the bending angle of the work from the side of the work using the visual sensor, since the two sides of the work viewed from the side of the work are generally far apart from each other, the bending angle can be detected without moving the visual sensor. It is difficult.
In addition, when both sides are imaged at two degrees and the bending angle is detected from both imaging states, it is difficult to obtain an accuracy of 0.1 to 0.5 degrees because the detection accuracy is the bending angle accuracy as it is.

Therefore, the present invention provides a bending apparatus that detects a current bending state and performs feedback control of a final bending position.
An object of the present invention is to provide a bending apparatus capable of obtaining good bending accuracy.

[Constitution of the Invention] (Means for Solving the Problems) In view of the above-described conventional problems, the present invention provides an upper apron supporting an upper mold and a lower apron supporting a lower mold vertically. And a control device for controlling one of the upper and lower aprons so as to be able to move up and down, and a control device for controlling the apron to move up and down, wherein the work is bent between the upper and lower molds. A visual sensor that visually detects the gradually decreasing clearance portion, and the clearance detected by the visual sensor when the work is bent by the upper and lower dies by the up and down movement of the apron. Is set to a preset value,
And a stop command signal output means for outputting a stop command signal to the control device to stop the vertical movement of the apron.

(Embodiment) Hereinafter, an embodiment of the present invention will be described using an example of a combined bending welding apparatus in which a bending apparatus is combined with a welding apparatus.

Referring to FIG. 1 and FIG. 2, a bending welding composite apparatus 1 includes, for example, a press brake 3 as a bending apparatus.
And a laser processing machine 5 that performs welding by, for example, thermal melting as a welding device.

On both sides of the lower frame 7D of the press brake 1, for example, C-shaped side frames 7R and 7L are provided. In the lower part on the front side of these side frames 7R and 7L,
Lower apron 9 is provided which is movable vertically to the appropriate height position by the driving device M _D based on the detection position of the position detector E _D. An upper apron 11 is fixedly provided on the upper front side of the side frames 7R, 7L. A die (lower mold) 15 is mounted on the lower apron 9 via a support member 13. A punch (upper mold) 19 is attached to a lower portion of the upper apron 11 via a support member 17.

With the above configuration, the work to be processed is placed on the lower mold 15 and the lower apron 9 is moved up and down with respect to the upper apron 11. Will be bent.

On the right side of the press brake 3, a laser oscillator power supply 21 of the laser processing machine 5 is provided. On the laser oscillator power supply 21, a laser oscillator 23 made of, for example, a CO ₂ gas laser is provided. When an oscillation command is input, a laser beam is output.

Referring additionally to FIG. 3, the upper apron
A support plate 25 extending in the left-right direction (hereinafter referred to as the X-axis direction) is provided on the front surface of the support 11. A plurality of parallel X-axis linear guides extending in the X-axis direction are provided on the front surface of the support plate 25. 27 are provided. This X-axis linear guide 27
Is provided so that the X-axis moving body 29 is moved in the X-axis direction. The X-axis moving body 29 includes an X-axis motor (servo motor) 31 for moving the X-axis moving body 29 in the X-axis direction.
Is provided.

An X-axis pinion 33 is attached to the output shaft of the X-axis motor 31. An X-axis rack 35 extending in the X-axis direction is provided on the front surface of the support plate 25, and the X-axis pinion 33 is engaged with the X-axis rack 35.

With the above configuration, when the X-axis motor 31 is driven, the X-axis pinion 33 rotates. X-axis pinion 33 is X-axis rack 35
When the X-axis pinion 33 rotates,
The X-axis moving body 29 is guided by the X-axis linear guide 27 via the X-axis rack 35 and is moved in the X-axis direction.

On the right side in FIG. 3 of the X-axis moving body 29, there is integrally provided a Z-axis guide 37 extending in a vertical direction (hereinafter, referred to as a Z-axis direction). One end of an extendable laser beam guide 39 is mounted on the upper part of the Z-axis guide 37, and the other end of the laser beam guide 39 is mounted on the left side surface of the laser oscillator body 23. An X-axis bend mirror 41 is built in the upper part of the Z-axis guide 37.

The Z-axis guide 37 is provided with a Z-axis column 43 extending in the Z-axis direction and movable in the Z-axis direction. Also,
A Z-axis motor (servo motor) 45 is provided on a lower side surface of the Z-axis guide 37, and a Z-axis pinion 47 is attached to an output shaft of the Z-axis motor 45.

On the other hand, the Z-axis column 43 is provided with a Z-axis rack 49 extending in the Z-axis direction, and the Z-axis pinion 47 is engaged with the Z-axis rack 49.

With the above configuration, when the Z-axis motor 45 is driven, the Z-axis pinion 47 is rotated. Since the Z-axis rack 49 is meshed with the Z-axis pinion 47, when the Z-axis pinion 47 rotates, the Z-axis column 43 is moved in the Z-axis direction via the Z-axis rack 49.

One end of a Y-axis guide 51 is attached to the lower end of the Z-axis column 43, and a Z-axis bend mirror 53 is provided on the lower end surface of the Y-axis guide 51. A Y-axis motor (servo motor) 55 is provided above the other end of the Y-axis guide 51. The output shaft of this Y-axis motor 55 has a Y-axis pinion
57 is installed.

The Y-axis guide 51 is provided with a Y-axis moving body 59 extending in the left-right direction (hereinafter referred to as the Y-axis direction) in FIG. 3 so as to be movable in the Y-axis direction. At the upper part, a Y-axis rack 61 extending in the Y-axis direction is provided. The Y-axis rack 59 is engaged with the Y-axis pinion 57.

With the above configuration, when the Y-axis motor 55 is driven, the Y-axis pinion 57 is rotated. Since the Y-axis rack 61 is engaged with the Y-axis pinion 57, when the Y-axis pinion 57 rotates, the Y-axis moving body 59 is moved in the Y-axis direction via the Y-axis rack 61.

3, the lower end of the A-axis rotating body 63 is mounted on the left end of the Y-axis moving body 59, and the Y-axis bending mirror 65 is provided on the lower end of the A-axis rotating body 63. A motor base 67 is provided below the A-axis rotating body 63, and an A-axis motor (servo motor) 69 is provided on the motor base 67. An A-axis pinion 71 is attached to the output shaft of the A-axis motor 69.
The shaft gear 73 is engaged.

With the above configuration, when the A-axis motor 69 is driven, the A-axis pinion 71 is rotated. A-axis gear on A-axis pinion 71
Since the 73 is engaged, when the A-axis pinion 71 rotates, the A-axis rotating body 63 is rotated in the A-axis direction via the A-axis gear 73 as shown by the arrow.

As shown in FIG. 6, an A-axis fixed body 75 is provided in the A-axis rotating body 63, and a hollow cylindrical body 77 extending in the Z-axis direction is provided at the axis of the A-axis fixed body 75. Is provided. A B-axis rotating body 79 is provided above the hollow cylindrical body 77.

A B-axis motor (servo motor) 81 is provided on the upper left side of the A-axis rotating body 63 in FIG. 5, and a B-axis pinion 83 is attached to the output shaft of the B-axis motor 81.
On the other hand, the B-axis rotating body 79 is provided with a B-axis gear 85. The B-axis gear 85 is engaged with the B-axis pinion 83. An A-axis bend mirror 87 is provided above the B-axis rotator 79, as shown in FIG.

With the above configuration, when the B-axis motor 81 is driven, the B-axis pinion 83 is rotated. B-axis gear on B-axis pinion 83
When the B-axis pinion 83 rotates, the B-axis rotator 79 rotates in the B-axis direction via the B-axis gear 85 as indicated by the arrow in FIG.

As shown in FIGS. 5 and 6, the B-axis rotating body 79 is provided with a C-axis moving body 89, and a nozzle is provided above the C-axis moving body 89 via a nozzle holder 91. 93 is installed. The C-axis moving body 89 has a B-axis bend mirror 95
Is built-in. Further, a condenser lens 97 is built in the nozzle holder 91.

A C-axis motor (servo motor) 99 is provided below the C-axis moving body 89.
A shaft pinion 101 is mounted. On the other hand, a C-axis rack 103 extending in the Z-axis direction is provided below the B-axis rotating body 79, and the C-axis pinion 101 is engaged with the C-axis rack 103. The C-axis moving body 89 has a fifth
As shown in the figure, a C-axis linear guide 105 is provided.

With the above configuration, when the C-axis motor 99 is driven, the C-axis pinion 101 rotates. Since the C-axis rack 103 is meshed with the C-axis pinion 101, when the C-axis pinion 101 rotates, the C-axis moving body 89 is guided by the C-axis linear guide 105 via the C-axis rack 103 to the third position. It is moved in the C-axis direction as indicated by the arrow shown in the figure.

Below the nozzle holder 91, for example, a capacitance type gap sensor 107 is integrally mounted. Therefore, when the C-axis moving body 89 is moved in the C-axis direction, the gap sensor 107 is also moved in the C-axis direction.

The C-axis motor 99 is provided with a C-axis motor main body 109 and a C-axis potentiometer 111, and the gap amount when the gap sensor 107 detects a gap indicates the C-axis potentiometer 111. Will be detected. It should be noted that more specific details are already known, and thus description thereof will be omitted.

As shown in FIGS. 5 and 7, the side surface of the C-axis motor 99 is provided with a substantially U-shaped bracket 113 to detect a clearance between abutting surfaces of workpieces, which will be described in detail later. A CCD camera 115 as clearance detection means is attached. Although not shown in the drawing when detecting the clearance between the butted surfaces of the workpieces with the CCD camera 115, a light source is provided near the CCD camera 115.

With the above configuration, the nozzle 93 attached to the tip of the C-axis moving body 89 is moved in the X-axis, Y-axis, and Z-axis directions, is rotated in the A-axis and B-axis directions, and is further moved in the C-axis direction. The Rukoto.

The laser beam LB oscillated by the laser beam oscillator 23 is sequentially reflected by the X-axis bend mirror 41, the Z-axis bend mirror 53, the Y-axis bend mirror 65, the A-axis bend mirror 87, and the B-axis bend mirror 95 and collected. The light is focused by the optical lens 97. The laser beam LB condensed by the condensing lens 97 is applied from the nozzle 93 to the butting surface of the work, and laser welding by thermal melting is performed.

As shown in FIG. 8, a control device for controlling the bending welding composite device includes a press brake 3 and a laser processing machine 5.
NC devices 117 and 119 that control
It is configured by combining at 21.

The press brake NC device 117 drives the bending position and actuator based on the bending conditions input from the manual data input device (MDi device) as an input device, that is, the material, plate thickness, shape, and the presence or absence of welding. a folded signal setting unit 123 for setting a signal for a programmable controller 125, a D-axis driving unit 127 for driving the D-axis control device M _D of the lower apron 9 while obtaining feedback signal Enkota Eb, line 121 The communication unit 129 is connected to the communication unit 129.

On the other hand, the NC device 119 of the laser processing machine includes a servo control unit 131 that controls the servo motors 31, 55, 45, 69, and 81 of the X, Y, Z, A, and B axes, respectively, and an input from the gap sensor 107. A sensor signal processing unit 137 that controls the C-axis motor 99 to follow the workpiece based on the signal, captures an image signal of the CCD camera 115 via the image processing device 133, and performs signal processing as appropriate in conjunction with the programmable controller 135; A communication unit 139 connected to the line 121 is provided.

The NC device 117 of this example performs control at the final bending position set in the bending position setting unit 123 in normal bending, but in the feedback control mode, the stop output from the NC device 119 of the laser processing machine. It has a function to stop the lower apron 9 during the slow bending operation on the spot based on the command signal.

The servo control unit 131 inputs the welding conditions input from the MDi device via the line 121, and welds the tip of the nozzle 93 near the welded portion, for example, a space position separated by 10 mm, that is, the C-axis drive thereafter. The waiting position at which the start can be started is obtained by using a coordinate exchange formula as appropriate, and the drive amount is distributed to each motor. or,
After the start of welding, a predetermined amount of movement is distributed to each motor so that the tip of the nozzle 93 is moved along the welding line of the welded portion.

The programmable controllers 125 and 135 receive a signal from each sensor including a limit switch (not shown) and the like, and perform a series of sequence processes so as to appropriately operate each actuator including a solenoid (not shown).

In particular, in the feedback control mode, the programmable controller 135 adjusts the clearance C detected based on the imaging signal of the CCD camera 115 to a predetermined clearance.
When C ₀ is reached, a stop command signal for the lower apron 9 is output to the programmable controller 125 of the press brake NC device 117.

9 and 10, a general bending welding operation is shown. As shown in FIG. 9, the press brake NC device 117 controls the die 15 based on the bending conditions input in step 901. Set the positioning position of.

That is, here, the moving position of the die 15 is determined in accordance with the shape of the die 15, the bending angle of the work, and the thickness of the work in order to bend the work W to a predetermined angle.

In the next step 902, the die 15 is moved to the set position.
The lower apron 9 is raised to move. In this case, the rising speed of the lower apron 9 is fast at the beginning, slow at the middle, and slow at the end. Moreover, the final position is one in which the amount of the position D ₀ which is set only in accordance with the amount of spring back α is an additional position.

When the movement to the predetermined position D ₀ + α is completed in Step 903, the apron 9 is lowered until Step S 905 determines D = D _{0 in} order to remove the distortion due to the spring back.

As described above, the tentative bending is completed. In step 906, a signal indicating the end of the bending is output to the NC device 119 of the laser processing machine.

Note that this example shows an example in which welding is performed after bending, but when welding is not performed, the lower apron 9 is lowered to the lower end in step 904, thereby completing one step of bending.

In step 907, the process waits while holding the work W between the punch 17 and the die 15 until a signal from the laser processing machine is input in step 908.

FIG. 10 is a process flowchart of the NC device 119 of the laser beam machine executed after the bending process of FIG.

In step 1001, the processing head including the nozzle 93 gap sensor 107 is positioned at a preset waiting position.

The waiting position is, for example, a position near the maximum width of the clearance C reduced in accordance with the bending operation of the welded portion Ws in the welding of the corner portion of the box bending shown in FIG. Is a position where welding can be started if the nozzle 93 is advanced.

Therefore, in step 1002, input of the bending end signal shown in step 906 of FIG. 9 is waited, and if this signal is input, the flow shifts to step 1003.

In step 1003, the gap sensor 107 is operated to drive the C axis, and the tip of the nozzle 93
It approaches the work W of the processing head until it becomes 2 mm.

Therefore, in step 1004, the CCD camera 115 detects the clearance C, that is, the amount C of the gap that is gradually reduced in accordance with the bending operation at the welded portion Ws. In step 1005, the amount C is set to a predetermined value C. It is determined whether it is ₀ or less.

Amount of clearance C ₀ which is set in advance is generally 15% of the input plate thickness t, that is, with 0.15 t.

When the C> C ₀ at step 1005, still bending of the press brake operation proceeds to step 1006 in view of the fact that not enough
An unacceptable NG signal is output to the NC device 117, and the process returns to the waiting position in step 1001.

If it is determined in step 1005 that C ≦ C _0, it means that the clearance C is suitable for welding and the bending angle is just right in FIG.

In the welding step 1007, the nozzle shown in FIG.
A laser beam is output from the tip of 93 and the nozzle 93 is welded.
The five axes X, Y, Z, A, and B are driven by an appropriate coordinate conversion formula so as to move along the welding line of Ws. After the end of welding, the processing head is moved to a predetermined position, and a welding end signal is output to the NC device 117 of the press brake in order to shift to the next bending step.

On the other hand, the NC device 117 of the press brake that has received the disable signal NG in step 1006 identifies this in step 908 of FIG. 9, and executes additional processing in step 909.

The additional processing here is to increase the positioning position shown in step 903 by a small amount β in order to execute additional bending in consideration of the fact that the clearance C is larger than the set value C ₀ and the bending is insufficient. It is. The amount β may be a constant value, for example, 0.05 mm, and if insufficient, the amount β may be added again. In addition, in order to perform more efficient work, the detected clearance amount C is transmitted in addition to the unacceptable signal NG in step 1006 in FIG. 10, and an additional amount β is determined based on the detected clearance amount C. Is also good. In this case, if the distance from the bottom of the welded portion Ws to the detection portion is l ₁ and the angle forming the clearance is Δθ, then l ₁ · tan Δθ = C, so Δθ = tan ⁻¹ (C / l ₁ ) in view, executes once additional bending so that the clearance C becomes a set value C ₀ or less.

Next, a bending process in the feedback control mode will be described with reference to FIG.

The feedback control mode is as shown in FIG.
The operation is appropriately performed in a bending process in which a clearance C capable of feedback control is generated.

In step 1301, in the same manner as set in step 901 of FIG. 9, depending on the bending condition, setting the bent position D ₀ tentative.

Next, in step 1302, the lower apron 9 is moved to the above position.
It raised toward the D _0, to determine that it has reached the position D ₀ -D ₁ near the provisional in step 1303, a very low speed at step 1304.

Therefore, in step 1305, the first
Start imaging clearance C shown in FIG. 12 at the detection position S, If a C = C ₀ at step 1306, outputs a stop instruction signal of the lower apron 9 via a programmable controller 135,125.

The NC device 117 of the press brake 3 stops the lower apron 9 on the basis of this signal, whereby the bending of the unit can be completed.

As described above, according to the present embodiment, the bending feedback control mode of the bending welding composite apparatus can be implemented, so that bending, welding, and cutting can be appropriately performed.

In particular, since the feedback control mode is added to the bending, high-precision bending can be performed, and advanced composite processing can be performed.

Also, in the bending welding composite apparatus in this example, a CCD camera 115
Is moved spatially together with the processing head of the welding equipment,
There is no need to provide a dedicated moving device for the D camera.

The present invention is not limited to the above embodiment, but can be implemented in other appropriate modes by making appropriate design changes.

[Effects of the Invention] As can be understood from the above description of the embodiments, in brief, the present invention provides an upper apron supporting an upper mold and a lower apron supporting a lower mold in a vertically opposed manner. One of the upper and lower aprons is provided so as to be able to move up and down, and in a bending apparatus including a control device that controls the apron that moves up and down, gradually reduces the size of the work when bending the work between the upper and lower molds. A visual sensor for visually detecting a clearance portion to be formed, and the clearance detected by the visual sensor when the work is bent by the upper and lower dies by the vertical movement of the apron is gradually reduced and set in advance. When the set value is reached, a stop command signal for outputting a stop command signal to the control device to stop the vertical movement of the apron is output. And force means.

As is apparent from the above configuration, in the present invention, a visual sensor that visually detects a clearance portion that becomes gradually smaller when a workpiece is bent between the upper and lower molds, and a vertical sensor that moves up and down by moving the apron up and down. Outputting a stop command signal to the control device to stop the vertical movement of the apron when the clearance detected by the visual sensor reaches a preset set value while the workpiece is being bent by the mold. Since the stop command signal output means is provided, as described in the embodiment, for example, the clearance of the portion to be welded of the work is detected by the visual sensor, and when the detected value becomes the set value, the bending of the work is performed. Since the workpiece is stopped, welding of a portion of the workpiece to be welded can be accurately performed in a subsequent process.

Also, according to the present invention, the clearance portion may be, for example, CC
Since the image is captured and detected by the visual sensor including the D camera, it is easy to display the clearance portion on the display device, for example, and it is possible to visually check the clearance.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a bending welding composite apparatus according to the present invention, FIG. 2 is a view taken in the direction of arrow II in FIG.
The figure is an enlarged detailed view taken along the line III-III in FIG.
FIG. 5 is an enlarged view of a portion viewed from an arrow V in FIG. 3, FIG. 6 is a partial cross-sectional view taken along an arrow VI in FIG. 5, and FIG. 8 is a block diagram of the control device, FIG. 9 is a flowchart of the bending process under the normal mode, FIG. 10 is a flowchart of the welding process, FIG. 11 is an explanatory diagram of the clearance, Fig. 12
FIG. 13 is a detailed explanatory diagram of the clearance shown as an enlarged front view of FIG. 11, and FIG. 13 is a flowchart of a bending process in the feedback control mode. 1. Composite bending welding apparatus 3. Press brake 5. Laser processing machine 9. Lower die (die) 19 ... Upper die (punch) 107 ... Gap sensor 115 ... CCD camera

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-62-227528 (JP, A) JP-A-1-210124 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B21D 5/02

Claims (1)

(57) [Claims] An upper apron supporting an upper mold and a lower apron supporting a lower mold are vertically opposed to each other, and one of the upper and lower aprons is vertically movable.
In a bending device comprising a control device for controlling an apron that moves up and down, a visual sensor that visually detects a clearance portion that gradually reduces when bending a workpiece between the upper and lower dies. When the clearance detected by the visual sensor is gradually reduced to a preset value when the work is bent by the upper and lower dies by the up and down movement of the apron, the apron is moved up and down. And a stop command signal output means for outputting a stop command signal to the control device to stop the movement.