JPH08132368A - Positioning method and device in plate working machine/ robot system - Google Patents

Abstract

PURPOSE: To realize the production continuation dealing with even the case in which the drooping and warp of a plate exist, by detecting the existence of the deviation of the route of plate tip portion, inserting, when there is deviation, the plate into a plate working machine by advancing the hand portion of an industrial robot respectively after ascending/descending the hand portion. CONSTITUTION: The hand portion 11 of a robot 1 advances in the state of holding a plate 13 toward a slab material processor 20, then detectors S1/N1, S2/N2 carry out detection when the tip side of the plate 13 droops downward or warps upward, and advance is made after ascending the hand portion 11 once at the time of downward droop and after descending the hand portion 11 at the time of upward warp. Also, when the detectors S1/N1, S2/N2 do not carry out detection, advance is made as it is. Thus, droop and warp are detected in the state of the plate 13 being actually inserted into the slab material processor 20, and its position is corrected according to its detection, so there is no chance of the plate 13 being hit against a mold or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning method and apparatus in a plate material processing machine-robot system. More specifically, industrial robots (hereinafter referred to as robots) handle and supply plate materials such as metal thin plates to plate material processing machines such as press brakes, NC turret punch presses, routers, etc., and plate materials are coordinated by the robot and the plate material processing machine. The present invention relates to a positioning method and device that can correct a positioning error due to sagging or warping of the tip of a plate when bending is performed.

[0002]

2. Description of the Related Art Conventionally, a playback type robot is used to insert a plate into a plate processing machine such as a press brake, and the robot grips the plate and bends one side of the plate so that the processed plate is a robot. Is known to be taken out (see Japanese Patent Laid-Open No. 59-175968).
In that case, it is also known that the plate material of the processing machine once taken out is turned or turned, and the side on the opposite side is processed while holding the same portion, and further, the entire four sides are processed.

When the above-mentioned robot inserts the plate material into the die of the processing machine, the robot is taught operation data such as the height of the hand portion and the amount of forward stroke so that the plate material can be inserted between the upper and lower molds. . Then, while maintaining the height thereof, the hand portion is advanced toward the mold, and the tip of the plate material is normally pressed against a stopper provided in the mold to position it. That is, the position in the height direction is the taught data, and the position is determined by the taught data of the position in the front-rear direction and the stopper.

[0004]

The above-mentioned conventional positioning method is premised on that the plate member is maintained horizontally by the hand portion. However, in actuality, depending on the length and thickness of the plate material and the position where it is gripped, the tip portion may hang down as shown in FIG. The amount of sag depends on whether or not the plate material is warped. For example, when the plate material is warped in the left-right direction, the front-back sag is small, when it is warped in the front-back direction, the upward sag is offset by the sag, and the downward sag is added to the sag. When one side is further processed, the sag and warpage are changed when the other side is processed. When such drooping or warping is large, the tip of the plate material may hit the mold, damaging the mold or the robot hand. In order to eliminate such problems,
The robot may detect sagging or warpage as a result of gripping the plate material or before inserting it into the mold, and stop it if it exceeds a predetermined range, but if it does so, it will often stop and production efficiency will decrease. . It is a technical object of the present invention to provide a positioning method and apparatus which can effectively utilize the flexible response force of a robot and can continue production in response to sagging or warping of a plate material.

[0005]

The positioning method of the present invention comprises:
A positioning method in a system in which a plate material is held in a substantially horizontal direction by an industrial robot and is inserted into a plate material processing machine, in the vicinity of an insertion port of the plate material processing machine, above and / or below the range through which the plate material should pass. There is a detector that detects whether or not there is a deviation, the industrial robot advances the plate material toward the plate material processing machine, and the detector detects whether or not there is a deviation in the path of the tip of the plate material, and there is no deviation When there is a deviation, the hand portion of the industrial robot is raised / lowered, and then the hand portion is advanced to insert the plate material into the plate material processing machine.

In such a method, it is preferable to correct the tilted state of the front and rear of the hand portion of the robot by the signal of the detector. Further, the detectors are provided in a pair on the left and right toward the plate processing machine, and when there is an error in the turning direction based on the signals from the left and right detectors, a correction value for the turning position in the horizontal plane is calculated, and the correction value is calculated according to the calculation result. The left and right inclinations of the plate material are corrected by turning the robot hand in a horizontal plane. Further, when a plurality of plate materials are sequentially inserted into the plate material processing machine, a correction value when a certain plate material is inserted is stored, and when the next plate material is inserted, first, by the route after the correction by the correction value. It is preferable to advance and then detect if there is a departure.

The positioning device of the present invention is a positioning device in a system in which a plate material is held in a substantially horizontal state by an industrial robot and is inserted into a plate material processing machine, and the plate material is provided near the insertion port of the plate material processing machine. A detector that detects whether the vehicle deviates above and / or below the range in which it should pass, and when the detector detects the deviation, corrects the traveling path of the hand part of the robot according to the detection result. It is characterized in that it is provided with means for calculating a value and means for issuing a command for raising and lowering to the hand portion of the robot according to the calculation result.

In such an apparatus, when the detector detects a deviation, means for calculating a correction value for the forward tilt or the backward tilt of the hand portion of the robot according to the detection result,
It is preferable to have a means for issuing a command for forward tilt / backward tilt to the hand part of the robot according to the calculation result. Further, the detector is provided in a pair of left and right toward the plate material processing machine, and means for calculating the correction value of the turning position of the plate material in the horizontal plane according to the signals of the left and right detectors, and the calculation result. Accordingly, it is preferable that the hand portion of the robot further includes means for issuing a command for turning in the horizontal plane. Further, it is provided with means for storing a correction value at the time of inserting a plate material, and means for reading the correction value at the time of inserting the next plate material and sending an operation command to the hand portion based on the correction value. Is more preferable.

[0009]

[Operation] With the robot hand holding the plate,
When moving forward toward the plate material processing machine, the detector detects when the front end side of the plate material hangs downward or warps upward. Then, when it hangs downward, the hand portion is once raised, and when it hangs upward, the hand portion is lowered and then moved forward. If the detector does not detect, move forward as it is. As described above, according to the method of the present invention, the sag and warp are detected in the state where the plate is actually inserted into the plate processing machine, and the position is corrected according to the detection, so that the plate is not bumped against the mold or the like. In addition to correcting the vertical position of the hand part, when the tip of the plate is drooping, the tip side of the hand part is raised, and when the tip is rising, the tip side of the hand part is lowered. If corrected to, the plate material is inserted in a more horizontal state, so that the processing is properly performed.

Further, when the detectors are provided on the left and right sides of the processing machine to correct the turning error of the plate material in the horizontal plane, there is an advantage that the correction can be surely made, as compared with the case where the plate material is simply collided with a stopper or the like. When processing multiple plate materials in order,
Since the tendency of sagging or warping of the plate material is often close, if you store the correction value for the previous plate material and insert it with the correction value for the next plate material, there is a high possibility that you can move forward as it is, so it is efficient. is there. The device according to the invention makes it possible to carry out the method described above.

[0011]

Embodiments of the method and apparatus of the present invention will now be described with reference to the drawings. FIG. 1 is a side view showing an embodiment of a positioning device of the present invention, FIG. 2 is a perspective view showing the whole of a robot and a processing machine equipped with the device, and FIGS. FIG. 5 and FIG. 6 are flowcharts showing, in that order, another embodiment of the method of the present invention.

1 and 2, the press brake 20 is of a type in which a lower die 22 moves up and down with respect to a fixed upper die 21, and hydraulic pressure is applied after an end portion of a plate member 13 is inserted between the upper and lower dies. Bending is performed by raising the lower die 22. The lower mold may be fixed and the upper mold may be moved up and down, or the upper and lower molds may be moved to face each other. Reference numerals R1 and R2 in FIG. 1 are determination ranges of detection amounts for detecting suitability of the approach path of the plate member 13, respectively, and R1 sets an upper limit and R2
Sets the lower limit. In addition, the area shown by the broken line shows an area where the condition is not good. Such a detector includes, for example, as shown in FIG. 2, the light projecting sides S1 and N1 and the light receiving sides S2 and N2 provided at the center and side of the front surface of the press brake 20.
It can be configured with a photoelectric detector or the like. Further, reference numeral 24 is a stopper for abutting and positioning the plate member 13.

The robot 1 shown in FIG. 2 is fixedly supported on the floor by a support base 2, and the output shaft (horizontal rotation shaft) 3A of the first speed reducer motor fixed to the upper part of the support base 2 has the press brake. It is arranged so as to coincide with the upper mold long axis 21A or the lower mold long axis 21B of 20. The output shaft 3A
Is attached with a first right-angle actuating arm 4 extending in a direction perpendicular to the output shaft 3A and the upper die long shaft 21A, and further with a second speed reducer fixed to the tip of the first right-angle actuating arm 4. The output shaft (horizontal rotation shaft) of the motor 5 has a second right angle working arm 6
Is installed. A third speed reducer motor 7 is fixed to the tip of the second right angle actuating arm 6, and a horizontal actuating arm 8 reaching the vicinity of the center of the press brake 20 is attached to the output shaft of the third reducer motor 7. Their first and second actuating arms 4, 6
The horizontal operating arm 8 can be rotated at an arbitrary angle by the respective drive motors.

A fourth reduction gear motor 9 is attached to the tip of the parallel operating arm 8 at a right angle to the parallel operating arm 8. An output head 10 has a suction head for gripping a plate member 13. 11 is provided. Reference numeral 14 in FIG. 1 is a processed product. In addition to the above mechanical parts, the robot 1 has a control box 15 having a built-in computer. The control box includes the photoelectric detectors (hereinafter referred to as sensors) S1 / N1 and S2 / N2 as shown in FIG. In response to the program, each motor 3, 5, 7, 9 is controlled according to the program.

In FIG. 1, reference numeral 30 is a computer unit, and the computer unit 30 is a central processing unit for arithmetically processing work condition data (such as the number of pieces processed and the number of sheets loaded) and robot motion data (such as speed and movement amount). (CP
U), a random access memory (RAM) for storing data in the middle of calculation or a program that has been taught in, a read only memory (RO) for storing a basic program
M) and the like. These data are input / output unit 31
It is input from the outside through and output to the outside. The motor drivers 33, 35, 37, 39 receive the output signals from the computer section 30 and convert the electric power so as to operate the motors 3, 5, 7, 9 of the respective shafts with reduction gears. The signals from the sensors S1 / N1 and S2 / N2 are also taken into the computer unit 30 through the input / output unit 31.

The teaching box 32 is for moving the robot 1 by a manual operation, and the data of the movement amount is stored in the computer unit 30 while causing the robot to perform a required operation by the manual operation. Reference numeral 40 is the press brake 2
It is a press brake control device for sending an operation signal to 0.

In the robot 1 having the above structure, the plate member 13
Sensor S1 / N1, which detects whether the approach path of
A part of S2 / N2 and the computer unit 30 constitutes a position detecting device. Further, the position detecting device and a mechanism for driving the suction head 11 of the robot 1 constitute a positioning device. The robot 1 and the press brake 20 configured as described above are almost the same as the conventional ones in the overall operation. That is, as shown in FIG. 3 and FIG.
Each one by one with the suction head 11 (step 11
0, FIG. 3 a), 180 while raising the suction head 11
Inverted (step 120), while holding the plate material 13 firmly from below, press the press brake 2 on the first side thereof.
0 between the upper and lower molds (step 130, FIG. 3b).

At this time, the first motor 3 and the second motor 5 are synchronously rotated in accordance with the program shown in FIGS.
As shown in, the plate member 13 is advanced in the direction of arrow A by a predetermined distance. During the forward stroke, the plate 13
Passes through the lower limit range R2 formed by the sensors N1 / N2 and the upper limit range formed by the sensors S1 / S2. Then, the computer section 30 judges whether the plate material is within a predetermined range (step 140), and if it is normal, the processing start signal is sent to the press brake 20 as it is to perform the processing (step 150, FIG. 3c). Then, when the processing of the first side is completed, the semi-finished product is extracted from the mold (step 160),
The second to fourth sides are similarly processed by changing the direction of the plate material (steps 220 to 470). After the processing of the fourth side is completed, the finished product 14 is stacked on the finished product stack (step 480, FIG. 3d).

On the other hand, when it is judged from the detection data that the positioning correction in the upward or downward direction is necessary,
A correction signal is sent to the second and third motors 3, 5, 7 to raise or lower them. Then, after the correction, the position is detected again (step 150), and the above-described detection and correction are repeated until the correct position is reached, and then the above-described processing and taking-out process is performed. When photoelectric sensors are installed on the left and right of the front side of the press brake, the light passes vertically, and only one of the sensors detects the tip of the plate first, so It is possible to detect the deviation of the rotation of. In that case, the deviation can be corrected by rotating the fourth motor 9. In the detection / correction process, if the number of repetitions exceeds the number in a predetermined range, the process can be stopped immediately without correction.

The above-mentioned cycle is to detect every time, but if it is corrected every time, the cycle time becomes long, and it is disadvantageous in that accuracy is maintained due to variations. Therefore, it is preferable to rewrite the teach-in data in advance based on the above detection result, and to make the robot operate based on the rewritten data, so-called learning control is performed.

The flowcharts of FIGS. 5 and 6 show an embodiment of learning control when the four sides of a rectangular work are bent in order. It should be noted that the process of inserting the work from the grip to the upper and lower molds and the staff for taking out the processed product are omitted, and only the essential parts are shown. The symbols X, Y, A, B
Indicates the teaching position of the robot X coordinate, Y coordinate, hand horizontal angle, and hand turning angle, respectively, and Xdi, Yd
i, Adi, and Bdi represent respective offset data, that is, the difference between the correct position and the taught position. Also, the sign i
Indicates which of the four sides is to be processed.

When the operation of moving from the previous point toward the stopper is started (step 510), first, which side of the learning data is used is selected, and the learning data is used, or it is ignored and cleared. Is selected (step 510). When processing a new shape work is started, it is cleared (step 520). Next, the number of times the correction / detection operation is repeated for the work is counted, and a predetermined number of times (determination value, eg, 10
When the above is repeated, the error is detected and the error is detected. That is, first, the counter is cleared (step 530), then it is judged whether or not the number of repetitions exceeds the judgment value (step 540), and if not, the counter "1" is added and the process proceeds to the next step (step 5).
50). When it exceeds, error processing such as stopping the machine is performed (step 545).

Next, teaching position data Xp, Yp, A
Offset data Xdi, Ydi, Adi,
A calculation for adding Bdi is performed (step 560), and the suction head is moved up or down or swung according to the new data X, Y, A, B (step 570 in FIG. 6). Then, the work upper limit sensor determines whether or not the new position is correct (step 580). If the new position is correct, the work lower limit sensor is determined (step 590), and if correct, the insertion operation is terminated (step 600), and the next Go to point. If the upper limit judgment is good and the lower limit judgment is bad, a predetermined set value, for example, "-1.0" is added to the value of "Y" of the offset data (step 610), and the number of repetitions is judged. (Step 540), the new data is used to move (Step 570). On the other hand, when the upper limit judgment is bad and the lower limit judgment is good, “1.0” is added to the value of “Y” of the offset data (step 62).
0), and similarly move through the counter to its new position (step 520). If neither the upper limit judgment nor the lower limit judgment is bad, it is judged that it is not a problem that can be corrected by positioning, such as abnormal deformation of the plate material, and the data is immediately returned to the count circuit without correction and finally error processing is performed. Perform (step 545). In this way, detection and movement are repeated until the correct position is obtained, but since offset data is stored as learning data, it is not necessary to repeat detection and correction from the next work.

If the cause of the offset is due to the warp of the plate material, for example, the positive and negative signs of the offset learning data on the left short side (i = 1) are reversed, and the right short side (i =
The data can be used for the processing of 2), and the data of the front long side (i = 3) can be used by reversing the positive / negative when processing the rear long side (i = 4).

When the cause of the offset is the bending of the work, it is considered that the offset amount of the left short side or the front long side is the same as the offset amount of the right short side or the rear long side. When i = 1) is added to the data on the right side (i = 2) as it is, the number of repetitions can be significantly reduced. In the above embodiment, the suction head is moved up and down to cope with the sagging of the plate material. However, when the tip of the plate material is sagging, the suction head may be tilted so as to lift the front end side. Good. That is, as shown in FIG. 1, since the plate material 13 is inclined from the position where the suction head 11 is gripped to the tip side, the suction head 1
By inclining 1 it is possible to lift the tip side of the plate material 13 and eliminate the lower limit defect.

[0026]

According to the position detecting method of the present invention, it is possible to efficiently deal with sagging and warping which are different for each plate material, and the efficiency of defective products is reduced. Further, by using the learning control method of the present invention, it is possible to reduce the amount of correction of the hand portion with respect to sagging or warping, and improve the production efficiency. The positioning device of the present invention can implement the above-described positioning method.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a positioning device of the present invention.

FIG. 2 is a perspective view showing an entire robot and processing machine equipped with the apparatus of FIG.

FIG. 3 is a process drawing showing an embodiment of a positioning method of the present invention.

FIG. 4 is a flowchart showing an embodiment of the positioning method of the present invention.

FIG. 5 is the first half of a flowchart showing another embodiment of the positioning method of the present invention.

6 is the latter half of the flowchart of FIG.

[Explanation of symbols]

 S1 sensor (light emitting side) S2 sensor (light receiving side) N1 sensor (light emitting side) N2 sensor (light receiving side) 1 Robot 11 Suction head 15 Control box 20 Press brake

Claims (8)

[Claims] 1. A positioning method in a system for holding a plate material in a substantially horizontal direction by an industrial robot and inserting the plate material into a plate material processing machine, the method comprising: (Or) Provide a detector to detect whether or not it is deviating downward, industrial robot advances the plate material toward the plate material processing machine, and the detector detects the deviation of the path of the plate tip However, when there is no deviation, as it is, when there is a deviation, the hand part of the industrial robot is raised / lowered, and then the hand parts are advanced to insert the plate material into the plate material processing machine / robot. Positioning method in system. 2. The method according to claim 1, wherein the front and rear tilting states of the hand portion of the robot are corrected by the signal of the detector. 3. A pair of left and right detectors are provided toward the plate processing machine, and when there is an error in the turning direction from the signals of the left and right detectors, a correction value of the turning position in the horizontal plane is calculated,
The method according to claim 1, wherein the left and right inclinations of the plate material are corrected by turning the hand part of the robot in a horizontal plane according to the calculation result. 4. When a plurality of plate materials are sequentially inserted into a plate material processing machine, a correction value when a certain plate material is inserted is stored, and when the next plate material is inserted, the correction value is first corrected by the correction value. The method of claim 1 wherein the trailing path is advanced and then detected if there is a departure. 5. A positioning device in a system for holding a plate material in a substantially horizontal state by an industrial robot and inserting the plate material into a plate material processing machine, which is provided in the vicinity of an insertion opening of the plate material processing machine, from a range through which the plate material should pass. A detector for detecting whether the vehicle deviates upward and / or downward, and a means for calculating a correction value of the traveling path of the hand part of the robot according to the detection result when the detector detects the deviation. And a positioning device including means for issuing an elevation command to the hand part of the robot according to the calculation result. 6. When the detector detects a deviation, means for calculating a correction value for forward or backward inclination of the robot hand unit according to the detection result, and a hand unit for the robot according to the calculation result. The apparatus according to claim 5, further comprising means for issuing a command of forward tilt / backward tilt. 7. A means in which the detectors are provided in a pair of left and right toward the plate material processing machine, and means for calculating a correction value of a turning position of the plate material in a horizontal plane according to signals from the left and right detectors, The apparatus according to claim 5, further comprising means for issuing a command for turning in a horizontal plane to the hand portion of the robot according to the calculation result. 8. A means for storing a correction value when a plate material is inserted, and a means for reading the correction value when the next plate material is inserted and sending an operation command to the hand portion based on the correction value. The apparatus of claim 5 comprising.