JP2813052B2 - Operating method of material displacement detection in laser pressing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an operation method for detecting a material position shift in a processing machine such as a laser press.

<Prior Art> As one of general-purpose processing machines for sheet metal materials, there is a so-called laser press processing machine that combines punching with a punch and fusing with a laser beam.

In recent years, FA (factory /
Automation) is being promoted, and in laser press machines, etc., robots for supplying the processing material, and for setting the processing material at predetermined positions, for the purpose of automatically supplying the processing material and automating the processing. A positioning device is provided. This positioning device performs positioning of a processing material by sucking a lower surface of a processing material supplied by a robot with a suction pad and moving the processing material to a predetermined reference position of a laser press machine.

A positioning device in a laser press machine will be described with reference to FIGS.

FIG. 8 is a perspective view showing a state in which a work clamp of a positioning device in a laser press machine grips a work material and the work material is processed by the laser press machine. FIG. 9 is a perspective view of FIG. The D section enlarged view is shown.

A laser press rod 3 is provided in the vicinity of the upper surface of the base 1, and a plurality of work clamps 5 protrude from a side surface of the laser press rod 3. The work clamp 5 holds the work material 7 between a pair of claws. The work clamp 5 is brought into contact with the pair of claws so that the work material 7 is moved in the Y-axis direction (a direction in which the work material 7 approaches and separates from the work clamp 5). Reference plane E as reference
Are formed (see FIG. 9). A location pin 9 serving as a reference in the X-axis direction (the longitudinal direction of the laser press rod 3) is provided on the upper surface of the base 1, and the location pin 9 has a structure that can be stored in the base 1. Accordingly, the work material 7 is positioned in the XY-axis direction by contacting the reference surface E of the work clamp 5 and the location pin 9.

A positioning confirmation sensor 11 is attached to the work clamp 5, and the positioning confirmation sensor 11 is turned on when the workpiece 7 hits the reference surface E of the work clamp 5. Right feed confirmation sensor 13 on base 1 side
The right feed confirmation sensor 13 is turned ON when the processing material 7 hits the location pin 9. That is, when both the positioning confirmation sensor 11 and the right-feed confirmation sensor 13 are turned on, it is determined that the processing material 7 is correctly set at a predetermined position of the laser press machine.
The claw of the work clamp 5 is closed by a control unit (not shown). After confirming that the work clamp 5 is closed, the location pin 9 is stored in the base 1. The work clamp 5 does not normally open until the laser press processing (a series of operations of punching and laser processing) is completed. However, when one work material 7 is used effectively, the work material 7 may be used by being turned 90 ° in the middle, and in such a case, the work clamp 5 is automatically turned on by the NC program. be opened. Only at this time, the operator intervenes and reverses the work material 7, presses the work material 7 against the reference surface E of the work clamp 5, closes the work clamp 5 again with a start operation switch (not shown), Continue press working.

As described above, the opening and closing of the work clamp 5 includes the case where the work clamp 5 is opened and closed when the workpiece 7 is positioned,
There is a case where the operator reverses the processing material 7 and presses it against the reference surface E of the work clamp 5 and starts a processing operation based on NC data by pressing a start operation switch (not shown).

Next, an example of a general plate removing process in a laser press machine will be described with reference to FIG.

FIG. 10 is an explanatory view showing an example of a plate cutting process in a laser press machine.

As shown in FIG. 8, while the work material 7 is being held and positioned by the work clamp 5,
The above-mentioned control unit (not shown) issues a processing instruction to the laser press machine. When a processing instruction is issued, the laser press rod 3 moves in the XY directions according to the instruction of the NC data.
With the movement of the laser press rod 3, the processing material 7 is moved, and X5 of the processing material 7 for confirming the position shift,
Point P1 of Y1 moves to the first punch position. Point moved
For P1, round punching is performed with the minimum punch diameter used for the board removal in accordance with the instruction of the NC data (the same punch diameter as point P2 described later in this description). Then, X2 of product A,
Move to point P2 of Y2 and perform round punching, and then X1, Y3
Move to point P3 and perform round punching with the same punch diameter as P2. Then, to perform pre-punch for fusing the product A by laser, move to the point P4 of X3 and Y4, and perform round punching with a minimum punch diameter used in the product A alone (in this description,
Punch diameter same as P2). Next, X2 and Y6 of product B
And then performs round punching with the punch diameter of point P2, and further moves in the order of point P6 of X3 and Y7 of product B and point P7 of X4 and Y5 of product C to perform pre-punching. As described above, when the same punch is designated, punching is continuously performed in the order of products A, B, and C until the punch operation instruction is completed.

Further, when the punch diameter changes, the laser press machine automatically changes the punch diameter, and again continues punching in the order of products A, B, and C. Then, when all the specified punching is completed, according to the NC data, an arrow Q1 is sent from the pre-punch positions P4, P6 and P7 in the order of product A to product B and product C.
The laser processing is performed as follows.

After the laser press processing (a series of operations of punching and laser processing) of the products A, B, and C is completed, the processing position returns to the point P1 of X5 and Y1 of the processing material 7 by the NC data instruction. This means that the laser press rod 3 returns by the movement amount in the XY axis direction moved from the points X5 and Y1 to the end of processing. Then, the cross mark is laser-cut at the point P1 at the punching positions X5 and Y1 by laser processing. As a result, the operator visually confirms the displacement between the punch hole formed at the point P1 at the start of the processing and the cross-shaped mark laser-cut at the point P1 after the laser processing is completed. It is determined whether or not the material 7 has shifted.

As described above, in the laser press working machine, the working order is first started by punching, followed by fusing by a laser beam, and finally, the operator confirms the positional deviation by punching holes and cross marks. It is to be performed in. Note that the plate cutting shown in FIG. 10 is an example, and there are many cases where punching and laser processing are actually performed in a more complicated order, but basically, the processing is performed in the above order.

<Problems to be Solved by the Invention> Conventionally, in order to detect a displacement of the processing material 7 in the laser press processing, a punch hole formed at the start of processing and a cross-shaped mark laser-cut after processing is completed. The comparison was visually determined. However, processing material 7
The end face sags (or warps) with the movement of the laser press rod 3 due to vibration during punching or a decrease in the rigidity of the processing material 7 after punching, and the laser press machine body And the work material 7 floats from the reference surface E of the work clamp 5 due to the momentum, and there is a possibility that a positional shift occurs during the processing. However, in the conventional operation method, a series of operations such as punching and laser processing are continued unless the processing material 7 comes into a very special state such as being disengaged from the claws of the work clamp 5. And punch holes and cross marks could not be confirmed. For this reason, there is a problem that the processing material in which the displacement has occurred is processed as it is. In addition, it is possible to cut the cross mark at the beginning of the laser cut, but then it was not possible to find a misalignment after the cross mark cut, which is likely to cause a shift, and the mark cut became meaningless. .

The present invention has been made in view of the above circumstances, and provides an operation method for detecting a material displacement in a laser press process in which a processed material is not continuously processed when a displacement occurs during a laser press process. It is another object of the present invention to prevent defective products and improve work efficiency.

<Means for Solving the Problems> In order to achieve the above object, a method for operating a material displacement detection in a laser press working according to the present invention comprises: holding a plate-shaped work material with a work clamp; A method of detecting a material position shift in laser press processing when performing the processing operation by moving the processing material, wherein the position of the processing material initially gripped by the work clamp is determined by the work clamp and the processing. The position of the work material gripped by the work clamp is detected by using the position shift detecting device during the working operation performed after that, and the position is detected using the position shift detecting device. Comparing the position of the processing material at the beginning of gripping detected by the position shift detection device with the position of the processing material monitored during the processing operation, Is determined to be within a preset allowable range, and if the difference is out of the allowable range and the workpiece clamp is still holding the work material at that time. For example, the processing operation is interrupted and an error is displayed.

<Operation> According to the operation method for detecting the material displacement according to the above procedure, when the work clamp grips the work material, first, the position of the work material at that time is detected using the position displacement detection device. The position of the work material is monitored using the position shift detection device even during the subsequent work, and the difference between the monitoring result and the position of the work material at the beginning of gripping is within a predetermined allowable range. It is determined whether or not there is. Therefore, if the relative position between the work material and the work clamp changes beyond the allowable range after the work material is gripped by the work clamp, this can be seen from the monitoring result of the displacement detection device. However, during the processing operation, the gripping state of the processing material may be released by, for example, a 90 ° reversal process of the processing material. If it is not in the state of being held, it is not determined that the displacement has occurred. In other words, if the change in the relative position after gripping the processing material is greater than the allowable range and the workpiece clamp is still gripping the processing material, it is determined that a positional shift of the processing material has occurred, and the processing operation is performed. Interrupt and display an error.

<Embodiment> A preferred embodiment of an operation method for detecting a material misalignment in laser press working according to the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a perspective view showing a laser press machine in which a detection device is attached to a work clamp of a laser press rod, and FIG. 3 is a perspective view showing a tolerance measuring instrument. FIG. 8 to FIG.
10, the same members as those shown in FIG.
Duplicate descriptions have been omitted.

A pair of displacement detectors 11a and 11b for detecting the displacement of the work material 7 are attached to the left and right sides of the work clamp 5 at both ends, and the displacement detectors 11a and 11b are attached to both ends of the work clamp 5. As a result, the detection of the displacement is performed best. The laser press rod 3 is provided with a pair of controllers 13a and 13b. The controllers 13a and 13b operate in pairs with the displacement sensors incorporated in the detection devices 11a and 11b, and convert a displacement amount from the displacement sensor into a voltage. It is supposed to. In this embodiment,
Left and right displacement detection devices 11a, 11b and controllers 13a, 1
3b are independently connected to a tolerance measuring device 15, which is a control means, shown in FIG. The tolerance measuring device 15 responds to the initial displacement voltage from the controllers 13a and 13b by using
13 when is set to work clamp 5
a, the difference between the reference displacement voltage from 13b and the displacement voltage from the controllers 13a and 13b when a displacement occurs,
This is a measuring device that outputs a positional deviation error information by comparing with a deviation amount value (voltage) within an error allowable range. The tolerance measuring device 15 allows the operator to freely specify the deviation amount (voltage) within the allowable range of the material deviation error.
In addition, a commercially available tolerance measuring device 15 can be used.

Next, the displacement detecting devices 11a and 11b will be described in more detail with reference to FIG.

 FIG. 4 shows a side sectional view of the position shift detecting device.

A detection head bracket (B / K) 17 is attached to the work clamp 5 provided on the laser press rod 3, and the detection head B / K17 has a displacement detection device 11a (11b).
Is attached. A block 19 of the displacement detector 11a (11b) is attached to the detection head B / K17, and a slide shaft 21 is slidably inserted into the block 19. A push flange 23 is connected to an outer end of the slide shaft 21. The slide shaft 21 and the push flange 23 are urged in the direction of the working material 7 (the direction of the arrow R) by a compression spring 25 provided inside the block 19, and
27 is a stopper. A displacement sensor 29 is disposed coaxially with the slide shaft 21 in the block 19, and the displacement sensor 29 is fixed to a rear end side of the block 19 via a sensor mounting plate 31. The displacement sensor 29 detects the distance from the slide shaft 21 and outputs the displacement accurately. Adjustment of the displacement sensor 29 with the sensor mounting plate 31 via the nut plate 33 is prevented from shifting. The connection cord 35 is connected to the displacement sensor 29, and the connection cord 35
The information from the displacement sensor 29 via the
a and 13b (see FIG. 2).

FIG. 5 is a block diagram of a control unit used in the present invention.

The control unit is a CPU 37, a ROM 39 for controlling according to the flowchart of FIG. 1, a memory (RAM) 41 for storing the operation status of the laser press machine and the tolerance measuring device 15, and data for operation instructions, a laser press machine. From the timer 43, which monitors the operation check status in response to the operation instruction to the laser press machine, the parallel I / O 45, which controls the exchange of signals from the tolerance measuring device 15, and the serial I / O 47, which controls the interface with external devices. It is configured.

FIG. 6 is a sectional view showing a state in which the processing material is set on the reference surface of the work clamp of the laser press machine.

The work material 5 is gripped by the work clamp 5,
The end of the work material 7 is in contact with the reference plane E of the work clamp 5. At the same time, the push flange 23 of the displacement detection device 11a (11b) is
And the push flange 23 is pressed in the direction of the arrow S by the work material 7. When the push flange 23 is pressed against the processing material 7, the slide shaft 21 connected to the push flange 23 is displaced by the displacement sensor 29.
The slide shaft 21 that has been moved in the direction is adjusted so as to stop when the distance between the slide shaft 21 and the displacement sensor is about 1 mm (see the F portion in FIG. 6).

FIG. 7 is a sectional view showing a moving state of a slide shaft in the position shift detecting device.

FIG. 7 shows a state in which the end face of the slide shaft 21 has moved from point B to point A. The slide shaft 21 moves left and right with reference to the point A, and the movement causes a change in the distance between the displacement sensor 29 and the slide shaft 21. The displacement sensor 29 detects the amount of change in the distance as the amount of deviation (voltage) of the work material 7 from the reference plane E. For example, when the slide shaft 21 moves in the right arrow T direction from the point A, the change is +, and when the slide shaft 21 moves in the left arrow U direction, the change is-. The end face of the slide shaft 21 connected to the push flange 23 and the tip of the displacement sensor 29 have a precise structure so that the amount of change in distance is directly proportional and detected by voltage.

In practicing the present invention, the work material 7 is set in advance at a predetermined position on the reference surface E of the work clamp 5 of the laser press machine by a robot hand or the like as shown in FIG. It is assumed that the processing can be performed at any time according to the press processing instruction.

Next, an operation method for detecting a material position shift in laser press working according to the present invention will be described with reference to FIG.

FIG. 1 is a flowchart showing an operation method for detecting a material position shift.

First, a processing instruction is given to the laser press machine by the above-mentioned control unit (see block 51 in FIG. 1; only the reference numerals attached to the blocks to be referred to are described below). Then, the laser press machine starts machining according to the instruction of the stored NC data. Next, the tolerance measuring device 15 shown in FIG.
In response, the control unit sends an auto-zero signal (53). Hereinafter, all the operation instructions and operation confirmations to be described are performed by the above-described control unit. At the point A in FIG.
The voltage corresponding to the distance between the displacement sensor 29 and the slide shaft 21 in (11b) becomes the reference displacement voltage, and the position thereof becomes the reference value of the future displacement.

The 90 ° reversal processing is controlled so that the processing of the laser press machine is temporarily stopped during the creation of NC data and the work clamp 5 is automatically opened (55, 5).
7). If the work is not stopped temporarily, or if the work is stopped but the work clamp 5 is closed, the control is changed to the displacement determination processing without executing the 90 ° reversal processing.

If it is determined that the process is 90 ° reverse processing, the process waits until the work clamp 5 is closed next (59). That is, the operator intervenes at that time, turns the work material 7 again by 90 °, sets the work material 7 on the reference surface E of the work clamp 5, and issues an operation instruction with a start operation switch (not shown). When an operation instruction is issued with the start operation switch, the operation of NC data starts and the pause function is released,
The work clamp 5 is closed and normal processing is started. The control unit determines that the 90 ° inversion processing has been executed, and sends out the auto-zero signal again to the tolerance measuring device 15 in FIG.
1).

The voltage with respect to the point A in FIG. 7, that is, the distance between the displacement sensor 29 of the displacement detection device 11a (11b) and the slide shaft 21 becomes the reference displacement voltage by the auto-zero signal transmitted again, and the position becomes the reference displacement voltage. It becomes the reference value. While the laser press machine performs machining in the order of punching and laser machining according to the instruction of the NC data, the distance between the displacement sensor 29 of the displacement detection device 11a (11b) and the slide shaft 21 changes every moment.
The detection device 11a (11b) always inputs the ever-changing displacement voltage to the tolerance measuring device 15.

During the processing work of the laser press machine, the detection device
When the voltage from 11a (11b) exceeds the allowable range of the amount of positional deviation (voltage) set in advance by the tolerance measuring device 15, positional error information is output from the tolerance measuring device 15 (63). In this case, when the amount of displacement is within the allowable range, the normal operation is continuously performed. If the work clamp 5 is open when the misalignment error is detected, it is determined that an instruction to invert the work material by 90 ° has occurred, and the normal operation is executed as it is (65).

Only when the position error is detected and the work clamp 5 is closed, it is determined that the original material position error has occurred. In this case, a stop instruction is sent to the laser press machine (67). At the same time, an error is displayed on the display unit of the control unit (69).

After that, the processing depends on the judgment of the operator, but it is necessary to change the NC data control sequence of the laser press machine only when processing is stopped there. Regardless of whether the operation is stopped or continued, the error is released from the laser press machine by pressing down the error release button (71) of the control unit (73).

Then, an auto-zero signal is immediately sent to the tolerance measuring device 15 (75). That is, the reference displacement voltage and the displacement error information when the displacement of the material occurs are reset by the auto-zero signal, the position of the current point A (see FIG. 7) is newly set as the reference displacement voltage, and the position will be changed in the future. Is the reference value for the displacement.

After resetting the new reference value of the displacement, the laser press machine is given a new machining instruction (77). It is not limited to the case where the laser press machine stops the operation again or continues due to the processing instruction sent again,
Until the processing end code (79) of the NC data is detected, the 90 ° inversion processing and the position error detection are repeatedly performed.

As described above, one position shift detecting device 11 has been described.
Multiple (two in the embodiment, 11a and 11b) misalignment detection devices
By monitoring 11a and 11b in parallel and operating with an error of any of the position shift detecting devices 11a and 11b, a position shift can be found more precisely.

<Effects of the Invention> As described above, according to the operation method for detecting a material misalignment in laser press working according to the present invention, the detection result of the misalignment detecting device at the beginning of gripping the work material and the monitoring result after that are obtained. If the difference is out of the allowable range and the workpiece clamp is still holding the work material, the processing operation is interrupted and an error is displayed. Therefore, even when displacement occurs during processing, the processing material is not continuously processed. As a result, it is possible to quickly cope with a material deviation during the processing, to prevent the occurrence of defective products, and to improve the working efficiency without performing unnecessary processing.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an operation method for detecting a material displacement, FIG. 2 is a perspective view showing a laser press machine in which a detection device is attached to a work clamp of a laser press rod, and FIG. 3 is tolerance measurement. FIG. 4 is a side sectional view of a position shift detecting device, FIG. 5 is a block configuration diagram of a control unit used in the present invention, and FIG. FIG. 7 is a cross-sectional view showing a state of being set on a reference surface of a work clamp of the machine, FIG. 7 is a cross-sectional view showing a moving state of a slide shaft in a position shift detecting device, and FIG. FIG. 9 is a perspective view showing a state in which a work clamp grips a processing material and the processing material is processed by a laser press machine, FIG. 9 is an enlarged view of a portion D in FIG. 8, and FIG. Press working It is a schematic diagram of a blank layout processing example in the. 5 Work clamp, 7 Work material, 11a, 11b Position shift detector, 15 Tolerance measuring device (control means).

Continuation of the front page (56) References JP-A-62-9731 (JP, A) JP-A-63-154232 (JP, A) JP-A-63-180121 (JP, U) (58) Fields investigated (Int) .Cl. ⁶ , DB name) B21D 43/00

Claims (1)

(57) [Claims] An operation method for detecting a material misalignment in laser press processing when a plate-shaped processing material is gripped by a work clamp and the processing material is moved through the work clamp to perform a processing operation. The position of the work material initially gripped by the work clamp is detected by using a position shift detection device that detects a relative position between the work clamp and the work material, and during the working operation performed thereafter. The position of the processing material gripped by the work clamp is monitored using the position shift detection device, and the position of the processing material at the beginning of gripping detected by the position shift detection device and the position of the processing material monitored during the processing operation. Comparing the positions with each other to determine whether or not the difference between them is within a predetermined allowable range, wherein the difference is out of the allowable range, and If the work clamp is in a state of holding the work material, the work operation is interrupted and an error is displayed.