JP2723994B2 - Gauging treatment method for bending equipment - Google Patents

Description

The present invention relates to a method of controlling a bending device in which a bending robot for a work supply service is applied to a bending machine, and particularly to a gauging process at the time of supply of a work. About the method.

(Prior Art) In recent years, in order to form a fully automatic bending line, a work supply service for a bending machine has been changed to a manual operation and is now performed using an articulated manpulake (bending robot).

However, in a bending machine, work positioning (gauging) is generally performed by a so-called back gauge device, and thus it is extremely difficult to position a work by a bending robot. That is, whether or not the work has hit the back gauge is detected by, for example, a limit switch. However, it is extremely difficult to control the bending robot with high accuracy so that the limit switch is operated exactly.

Therefore, conventionally, instead of a back gauge device having a limit switch for detecting abutting, a position detection device such as a potentiometer capable of detecting a position within a fixed stroke is provided, and a workpiece is approached in an operation area of the position detection device. Correction of a workpiece to a normal state according to the detection position of the position detection device has been performed (for example, Japanese Patent Application Laid-Open No. S59-227379 (method and method for supplying a workpiece). Since the approach may be set within the operation area of the position detection device, the control of the bending robot becomes relatively easy.

(Problems to be Solved by the Invention) However, in the bending robot control method proposed as described above, the mutual interference problem between the workpiece, the bending machine, and the bending robot has been sufficiently studied. I didn't.

That is, an interference problem occurs between these members in the following state, and a countermeasure is required.

Do not let the bending robot grip the workpiece,
When gauging operation (including approach) is performed,
Since the workpiece never hits a position detecting device such as a potentiometer, the bending machine continues to operate in the forward direction and may interfere with the bending machine.

If the workpiece does not strike the position detecting device, the workpiece or the bending robot may interfere with the bending machine.

If there is no room for the position detecting device after the approach is completed, there is a risk that the position detector will be broken by the work in the next gauging operation (parallel alignment and positioning to the bending position).

If the work held by the bending robot has a large deviation in rotation or position, the position detection device on one side does not operate forever, and as a result, the work hits the bending machine.

If one end of the work touches the position detecting device but then comes off again, the position detecting device becomes undetectable and the work strikes the bending machine.

If an obstacle such as slippage occurs in the gripping portion of the bending robot, the work may unexpectedly move and hit the bending machine.

If these interference problems are to be countered only by some type of interference or prevention device, such as by providing a large number of sensors, not only will the device cost be increased, but also the bending operation of the device may hinder the bending operation. is there.

Therefore, an object of the present invention is to provide a gaging processing method of a bending device that can prevent interference between a bending machine, a workpiece, and a bending robot without providing a large number of special sensors and can smoothly perform a gaging operation. .

[Structure of the Invention] (Means for Solving the Problems) In the present invention for solving the above problems, as shown in FIG. 1, a work supply service is provided by a bending robot to a bending die of a bending machine. A gauging processing method for a bending device, wherein a front / rear position detecting device for individually detecting a front / rear position of a front end of a work inserted in the mold direction within a predetermined stroke at two left and right positions near both ends of the work is provided; Move the front end of the workpiece gripped by the bending robot based on the gauging command shown at 101 toward the front-back position detection device,
In step 102, the workpiece is positioned at a predetermined approach position, and then in step 105, the workpiece is positioned parallel to the mold and positioned in a bending position. During this time, detection is performed in step 103 until gaging is completed in step 106. An alarm is detected by an abnormality detection routine set in advance in step 104 in accordance with the operation and the operation amount of the two front and rear position detection devices.

As the abnormality detection routine, the following routines can be appropriately combined and used.

A routine for outputting an alarm when the movement amount of the front / rear position detection device does not change in accordance with the operation of the bending robot when the parallel positioning and the positioning to the bending position are performed.

A routine for outputting an alarm when the amount of movement of at least one of the front and rear position detection devices performs an extremely large operation in accordance with the control operation of the bending robot at the time of positioning in the paralleling and bending positions. .

At the time of positioning to the parallel position and the bending position, as a result of repeating the bending operation and the positioning operation to the bending position of the bending robot an appropriate number of times, at least one of the front and rear position detecting devices has an operation amount. Routine that outputs an alarm when it is zero.

A routine for outputting an alarm when the positioning position of the approach at the time of performing the positioning process to the parallel alignment and bending position is too close to at least one of the front-back position detection devices.

(Operation) In the gaging processing method of the bending device according to the present invention, the above-described routine is operated during the parallel processing with the approach and the positioning processing to the bending position. Abnormality can be detected without coming.

Thus, in this routine, it is possible to detect a case where the approach is too far or an abnormality on the bending robot side including the grip portion.

In this routine, an unexpected sudden operation on the work side is set as an alarm, so that a large deviation of the gripping position of the bending robot, a software error, and the like can be detected.

Further, in the routine, since the detection position does not change even after a plurality of control cycles, it is possible to detect an approach failure, a work deviation, and the like.

In addition, the routine can prevent interference due to a failed approach.

(Example) Hereinafter, an example of the present invention will be described.

FIG. 2 is a plan view showing a main part of a positioning system of the bending device according to one embodiment of the present invention.

As shown in the figure, in the positioning system of this example, a stretch 2 is arranged along a mold 1 and the movable body can move independently of the stretch 2 in the left-right direction (X direction) in the figure.
3,4 are provided. Each of the moving bodies 3 and 4 is provided with potentiometers 5 and 6 for detecting a front end position of the work W in a Y direction orthogonal to the X direction. In the X direction, the right direction in the figure is positive (+), the reverse direction is negative (-), and in the Y direction, the upper part in the figure is positive (+) and the lower part is negative (-).

The potentiometers 5 and 6 are fixed to stoppers 7 and 8 fixed to the moving bodies 3 and 4, respectively.
It is possible to detect the front end position of the work W located within a predetermined distance (for example, 25 mm) in the axis negative (-) direction. That is, the front end position of the work W on the Y-axis can be detected by detecting the distance from the front ends of the stoppers 7 and 8 to the front end of the work W.

The rear end of the work W is gripped by the hand 9 of the bending robot, and is provided with a work supply service. The robot is composed of, for example, six axes (including orthogonal X, Y, Z, and rotation A, B2 axes). The hand 9 is the work W
Is moved in the front-rear (Y) direction, and the pivot 10
Is used as a fulcrum to rotate in the left-right direction (B direction), and various axes (not shown) are driven to determine the posture of the work W and to position it on the X and Y axes.

FIG. 3 is a block diagram showing a configuration example of a control device of the positioning system.

As shown, the control device of the present example has a shared RAM 13 connected to two CPUs 11 and 12. The CPU 11 is connected to a bus 14, to which a ROM 15, a RAM 16, and an A / D converter 17 are connected. The A / D converter 17 is connected to the potentiometers 5 and 6 via an analog selector 18. On the other hand, the CPU 12 is connected to a bus 19 connected to the shared RAM 13, and a ROM 20 and a robot drive unit 21 are connected to the bus 19.

Therefore, in the control device of this example, the potentiometer
5,6 detected values Y _1, Y ₂ analog switches 18, A / D converter 17
, And to the CPU 12 via the shared RAM 13.

FIG. 4 is a flowchart of the gauging process executed after the approach. The approach is performed when the stretch 2 approaches a work positioned in advance slightly before the regular positioning position to a predetermined approach position.

If there is a difference between the left and right potentiometers 5 and 6 in step 401, the B-axis is moved so that the difference becomes zero (0) in step 402, and then in step 403 it is determined whether or not the value of the potentiometer has reached a target value. If the target value has not been reached, the Y-axis is moved in step 404 to make the difference zero. The processing of steps 401 to 405 is repeated until it is confirmed in step 405 that both the left and right have reached the target values.

 The occurrence status of the abnormal state is shown in FIGS.

FIG. 5 is an explanatory view showing a state where the workpiece W of the hand 9 is not gripped. If the gauging process shown in FIG. 4 is executed in this state, the hand 9 may hit the bending machine.

FIG. 6 is an explanatory diagram showing a state in which the tip end of the work W hangs down and gets over the potentiometers 5 and 6. In this case, the work W may cause interference with the bending machine. R / B indicates the robot body.

FIG. 7 is an explanatory view showing a state in which the tip end of the work W is warped with respect to FIG. In this case, the same interference as in the case of FIG. 6 may occur.

FIG. 8 shows a state in which the work W is too close to the potentiometers 5 and 6 due to a poor approach. In this case, since the gauging process is performed in a fixed cycle operation as shown in FIG. 4, the potentiometers 5 and 6 may be broken by the unit operation of the work W.

FIG. 9 is an explanatory diagram of a state in which the hand 9 holds the workpiece W while being shifted. In this case, the work W does not perform the expected operation and may interfere with the bending machine.

FIG. 10 is an explanatory diagram of a state where the work W is shifted in the left-right direction. Also in this case, for example, the work end on the right side in the drawing may interfere with the bending machine.

FIG. 11 is an explanatory view showing a state in which the work W has once hit the potentiometers 5 and 6, but then jumps up in the direction indicated by the arrow 22, and comes off the upper side of the mold 1.
Also in this case, the tip of the work W may interfere with the bending machine.

Next, an example of a routine for detecting the above abnormal state and outputting an alarm will be described.

Fig. 12 shows the routine for detecting abnormal operation restoration (ROUTINE
ERR-DET).

Step up In this routine, after approach at step 1201, stores the initial value Y _10, Y ₂₀ of the potentiometer 5 and 6 at step 1202, the gauging completion is determined in step 1205 as a result of the gauging operation in step 1203 An abnormality is determined in 1204, and an alarm is output in step 1206. The abnormality determination here is based on potentiometer outputs Y ₁ and Y ₁
Whether ₂ is equal to the initial value, that is, Y ₁ = Y ₁₀ , Y ₂ = Y ₂₀ is determined, and an alarm is output when the result is positive (YES). However, whether to actually output this alarm can be specified by parameter setting for the alarm output.

In this routine, the values of the potentiometers 5 and 6 do not change in spite of the gauging operation by the discrimination in step 1204. Therefore, in addition to the abnormalities shown in FIG. 5, FIG. 6, and FIG. An abnormality on the robot side can be determined. Also, when the gauging operation in step 1203 is defined as a series of operations, the gauging operation indicates a state in which the work has returned to the original position, so the approach position is originally set to be shifted from the desired position. An abnormality can be detected as a state that is practically impossible.

Fig. 13 shows a routine (ERR
-NOLIN).

In this routine, approach is performed in step 1301, initial values Y ₁₀ and Y ₂₀ are stored in step 1302, and gauging operation is performed in step 1303. Until gaging is determined in step 1305, abnormality determination is performed in step 1304. Is done. Here, the abnormality is determined by the amount of change | Y ₁ −Y ₁₀ | or | Y of potentiometers 5 and 6 in one gauging operation.
_This is for comparing whether or not _2- Y ₂₀ | is equal to or greater than a predetermined value a. The predetermined value a is a potentiometer when approaching
If 5 and 6 are working, for example 2mm, otherwise
This is a value determined by a parameter, such as 6 mm. If the answer is YES in step 1304, an alarm is output in step 1306.

Accordingly, in this routine, it is determined in step 1304 that the potentiometers 5 and 6 have abnormally large values, and therefore, as shown in FIG. 11, the work W is suddenly separated from the potentiometers 5 and 6, as shown in FIG. Can be detected.

FIG. 14 shows a routine (CONGA) for detecting a workpiece detachment.

In this routine, when approaching is performed in step 1401 and gauging operation is performed in step 1402, abnormality is determined in step 1403 until completion of gauging is determined in step 1404. Here, the abnormality determination is performed when _one of the values Y ₁ and Y ₂ of the potentiometers 5 and 6 is zero (0) and there is no change regardless of the gauging operation of a preset number of times (CNTY and CNTB). It is determined whether W is out of the potentiometers 5 and 6 (see FIGS. 9 and 10), and
The alarm is output at 05. CNTY indicates the number of Y-axis operations, and CNTB indicates the number of B-axis operations.

FIG. 15 shows a routine (INIGAU) for detecting an abnormality of the work W approaching the potentiometers 5 and 6 too much.

In this routine, and approach in step 1501, as a result of storing the initial values Y _10, Y ₂₀ of the potentiometer 5 and 6 at step 1502, later by the abnormality detected in step 1503, the abnormality otherwise if Step 1504 to the following gauging operation It is a transition. At step 1503, Y ₁ or the long Y ₂ is 2mm or less, the workpiece W are too close to each potentiometer 5,6, in the next gauging operation, can damage the potentiometer 5,6 (See FIG. 8.) Therefore, an alarm is output in step 1505.

As described above, in this example, gauging can be executed without any trouble by activating the abnormality determination routine as shown in FIGS. 12 to 15 in accordance with the gauging operation.

The present invention is not limited to the above embodiments, but can be implemented in an appropriate mode by making appropriate design changes.

[Effects of the Invention] As described above, since the present invention is a gaging processing method for a bending device as described in the claims, an abnormality that can cause interference between the bending machine, the workpiece, and the bending robot is detected and an alarm is output. Therefore, interference between the bending machine, the workpiece, and the bending robot can be prevented without providing a large number of special sensors, and the gauging operation can be smoothly performed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an outline of the present invention, FIG. 2 is a plan view of a work positioning system in a bending device according to an embodiment of the present invention, FIG. 3 is a block diagram of a control device, and FIG. FIG. 5 is a flowchart showing an example of the operation, FIG. 5 to FIG.
FIG. 12 is a flowchart showing a routine for detecting a work operation restoring abnormality, FIG. 13 is a flowchart of a routine for detecting an abnormal operation of the work, FIG. 14 is a flowchart of a routine for detecting detachment of the work, and FIG. It is a flowchart of the routine which detects too close to a potentiometer. 2 ... Stretch 5,6 ... Potentiometer 9 ... Robot hand

Claims (5)

(57) [Claims] In a gauging method for a bending apparatus for providing a work supply service to a bending die of a bending machine by a bending robot, a front-to-rear position of a front end of a work inserted in the direction of the die is set to a position near both ends of the work. A front-rear position detecting device for individually detecting within a predetermined stroke at two left and right positions is provided, and a work front end held by the bending robot is moved toward the front-rear position detecting device, and positioned at a predetermined approach position. The workpiece is positioned parallel to the mold and positioned at a bending position. During this time, an alarm is detected by a preset abnormality detection routine in accordance with the operation and the operation amount of the two front and rear position detection devices. A gaging treatment method for a bending device. 2. The gaging processing method for a bending device according to claim 1, wherein the abnormality detection routine is configured such that, when the parallel positioning and the positioning to the bending position are performed, the operation amount of the front / rear position detecting device is determined by the amount of movement of the bending robot. A gaging processing method for a bending device, comprising a routine for outputting an alarm when the signal does not change according to the operation. 3. The gauging processing method for a bending device according to claim 1, wherein the abnormality detection routine operates at least one of the front and rear position detection devices when positioning to the paralleling and bending positions. A gaging processing method for a bending device, comprising: a routine for outputting an alarm when an amount of operation is extremely large according to a control operation of a unit of the bending robot. 4. The gauging processing apparatus for a bending device according to claim 1, wherein the abnormality detection routine includes the paralleling operation of the bending robot and the positioning to the bending position when the parallelizing and positioning to the bending position are performed. A gaging processing method for a bending device, comprising: a routine for outputting an alarm when at least one of the front and rear position detection devices has an operation amount of zero as a result of repeating the operation an appropriate number of times. 5. The gauging processing method for a bending device according to claim 1, wherein the abnormality detection routine is such that the positioning position of the approach when performing the paralleling and positioning to the bending position is at least the front-back position detection. A gaging processing method for a bending device, comprising: a routine for outputting an alarm when one of the devices is too close.