JP4280332B2 - Method and apparatus for measuring bending angle in bending machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bending angle measuring method and a bending angle measuring apparatus in a bending machine such as a press brake.
[0002]
[Prior art]
Generally, a bending machine such as a press brake equipped with an NC device is provided with a drive mechanism for a table drive shaft on each of the left and right sides, and the NC device is based on a D value (depth value) corresponding to a target angle. Each drive mechanism is controlled to bend the workpiece to near the target angle.
[0003]
Here, the D value is the distance between the punch and the die corresponding to the target angle (ie, the distance between the blades), in other words, the amount of pressurization stroke of the table corresponding to the target angle. Depending on the type of NC device, the operator directly inputs and sets the D value, and the operator only has to input the target angle, and the NC device calculates the corresponding D value based on the target angle. There is a type of which is obtained and set according to.
[0004]
In both types, the finished angle is within the allowable range by operating the hand pulser (manual operation pulse generator) as needed to drive the workpiece after bending (increment bending). It is done to fit.
[0005]
In such a bending machine, if the work after the bending process is removed from the bending machine, it is inevitable that a springback occurs. The bending angle widened by the amount of the spring back is the finished angle of the workpiece.
[0006]
Therefore, at the time of actual bending, it is necessary to set the angle into which the springback amount has been incorporated as the target angle instead of setting the original angle to be finished as the target angle. It is required to know in advance how much springback will occur in the workpiece.
[0007]
For this reason, conventionally, an operator first performs a test bend using a workpiece and measures the amount of springback from the workpiece.
[0008]
[Problems to be solved by the invention]
However, the conditions for accurately measuring the amount of springback ((1) The pressurization by the NC is accurately performed to the target angle. (2) The bending angle of the workpiece at the final pressurization is accurately measured. 3) After removing the pressurization, the bending angle can be measured accurately with the workpiece fully unloaded.) In the conventional method, if it is not an experienced operator, it can be performed once or twice. It is difficult to accurately determine the amount of springback in the work, and it is not always possible to accurately determine the amount of springback if the trial bending is repeated many times. It is actually very difficult to grasp and set the angle where the amount of springback has been incorporated as the target angle, and as a result, it is possible to improve the accuracy of workpiece finishing. There is a problem that it is difficult.
[0009]
The present invention solves the above-mentioned problems of the conventional apparatus, and can accurately measure the amount of springback of the workpiece in bending, and can effectively use the measured amount of springback, thereby It is an object of the present invention to provide a method and apparatus for measuring a bending angle in a bending machine capable of improving the finishing accuracy.
[0010]
The present invention can also accurately measure the amount of spring back of the workpiece in bending, and can effectively use the measured amount of spring back, thereby improving the accuracy of workpiece finishing. Furthermore, it is an object of the present invention to provide a bending angle measuring method and apparatus for a bending machine that can be easily applied to a bending machine equipped with an existing NC apparatus.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention includes a step of pressurizing a workpiece to a vicinity of a target angle by a bending machine, a step of measuring a bending angle of the workpiece at the time of final pressing and holding the measured value, and pressurizing. Using the step of removing and placing the workpiece in an unloaded state, the step of measuring the bending angle of the workpiece in the unloaded state and holding the measured value, and the final pressure angle measured value and the unloaded angle measured value , And a step of obtaining an angle difference between the two and a step of registering the obtained angle difference as a springback amount.
[0012]
In this way, by registering the angle difference between the bending angle of the workpiece at the time of final pressurization and the bending angle of the unloaded workpiece as the springback amount, the springback amount of the workpiece in bending can be accurately measured. In addition, the measured springback amount can be used effectively.
[0013]
The present invention also includes a step of pressurizing the workpiece to the vicinity of the target angle by the NC device, a step of measuring the bending angle of the workpiece at the final pressurization and holding the measured value, and removing the workpiece from the bending machine. Using the load process, measuring the bending angle of the unloaded workpiece and holding the measured value, and using the final pressurization angle measurement value and the no-load angle measurement value, And a step of registering the obtained angle difference as a springback amount.
[0014]
In this way, the bending angle of the workpiece at the time of final pressurization by the NC device is measured, the bending angle is measured with the workpiece in an unloaded state, and the angle difference between the two is registered as the springback amount, thereby bending the workpiece. Thus, the amount of spring back of the workpiece can be measured accurately, and the measured amount of spring back can be used effectively.
[0015]
Further, the present invention provides a driving control means, a step of setting a target angle in the driving control means, a step of setting a D value corresponding to a provisional bending angle smaller than the target angle in the NC device, and a work by the NC device. Based on the angle error between the angle measurement value and the target angle, the drive control means automatically drives into the NC unit based on the process of pressurizing and bending to near the temporary bending angle, the process of measuring the bending angle of the workpiece at the end of the temporary bending A driving process for transferring the number of pulses necessary to execute the operation to drive the workpiece to the target angle, a final pressurization angle measurement process for measuring the bending angle of the work at the end of the driving, and a work after removing the pressure From the difference between the process of making the unloaded state, the unloaded angle measuring process of measuring the bending angle of the unloaded workpiece, A step of obtaining a spring-back amount, and a step of registering the amount of spring back obtained.
[0016]
In this way, the workpiece bending angle is measured by measuring the bending angle of the workpiece at the end of driving, measuring the bending angle with the workpiece unloaded, and obtaining and registering the springback amount from the difference between the two. The back amount can be measured accurately, and the measured spring back amount can be used effectively.
[0017]
The present invention also includes a step of providing a follow-up measuring means, setting a target angle in the follow-up measuring means, a step of setting a D value corresponding to a provisional bending angle that is less than the target angle in the NC device, and a work by the NC device. A step of pressurizing and bending to near the temporary bending angle; and a step of measuring the bending angle of the workpiece and displaying the measured value during the manual driving operation by the operation of the pulse generator following the temporary bending; and When the angle measurement value becomes an angle corresponding to the target angle, the follow-up measurement means holds the measurement angle at that time as the final pressurization angle measurement value, and removes the pressurization to make the workpiece unloaded. Using the process, the step of measuring the bending angle of the unloaded workpiece and holding the measured value, and the final pressure angle measured value and the unloaded angle measured value, the spring back amount of the workpiece is determined. And Mel step, and a step of registering the amount of spring back obtained.
[0018]
In this way, during the manual driving operation following temporary bending, the bending angle of the workpiece is measured and displayed, the final pressure angle measurement value is retained, the workpiece is unloaded, and the unloaded angle measurement value is retained. By obtaining and registering the springback amount from both, the springback amount of the workpiece in bending can be accurately measured, and the measured springback amount can be effectively used.
[0019]
In addition, the present invention provides an NC device after the work is bent to the vicinity of the temporary bending angle by the operating means for setting the target angle and the NC device for which the D value corresponding to the temporary bending angle that is less than the target angle is set. A pulse generator that generates the number of pulses required to execute the automatic driving operation for driving the workpiece to the target angle, and the NC device performs the automatic driving operation using the pulses transferred from the pulse generating device. When the bending angle reaches an angle corresponding to the target angle, a pressure angle measuring means for measuring the angle, a no-load angle measuring means for measuring the bending angle of the unloaded workpiece after the pressure is removed, The springback amount is obtained from the difference between the final pressure measurement value of the workpiece by the pressure angle measurement means and the no-load angle measurement value of the work by the no-load angle measurement means. And a control means for registering.
[0020]
Thus, the pressurization angle measurement means measures the final pressurization angle of the workpiece, the no-load angle measurement means measures the no-load angle of the work, and the control means obtains the springback amount from the difference between the two and calculates it. By registering, it is possible to accurately measure the springback amount of the workpiece in the bending process, and to effectively use the measured springback amount.
[0021]
Further, the present invention provides the pulse generation after the work is bent to the vicinity of the temporary bending angle by the operating means for setting the target angle and the NC device for setting the D value corresponding to the temporary bending angle that is less than the target angle. During the manual driving operation to drive the workpiece to the target angle by operating the instrument, the pressure angle measuring means for measuring the bending angle of the workpiece, the means for displaying the angle measurement value by the pressure angle measuring means, No-load angle measuring means for measuring the bending angle of the workpiece in the no-load state after the pressure is removed, the final pressurization angle measurement value by the pressurization angle measurement means at the end of manual driving, and no load by the no-load angle measurement means Control means for obtaining a springback amount from the difference from the angle measurement value and registering it.
[0022]
In this way, the control means determines the springback amount from the difference between the final pressure angle measurement value of the workpiece by the pressure angle measurement means at the end of manual driving and the workpiece no-load angle measurement value by the no-load angle measurement means. By obtaining and registering it, it is possible to accurately measure the springback amount of the workpiece in the bending process, and to effectively use the measured springback amount.
[0023]
Furthermore, the present invention provides a workpiece near a temporary bending angle by an operating means for setting a target angle, a pulse generating means for automatic driving, and an NC device for setting a D value corresponding to a temporary bending angle that is less than the target angle. After the bending operation, the NC device drives the workpiece to the target angle based on the applied pulse. During the driving operation, the pressure angle measuring means for measuring the bending angle of the workpiece, and after the driving is finished, the pressure is removed. The difference between the no-load angle measurement means that measures the bending angle of the unloaded workpiece, the final pressurization angle measurement value by the pressurization angle measurement means at the end of driving, and the no-load angle measurement value by the no-load angle measurement means From the control means for obtaining the springback amount and registering it, and the pulse generation source applied to the NC device to either the pulse generator or the pulse generation means And a switching means for changing Ri is connectable to the NC apparatus via the switching means.
[0024]
As described above, the control means obtains the springback amount from the difference between the final pressure measurement value of the workpiece by the pressure angle measurement means at the end of the driving and the no-load angle measurement value of the work by the no-load angle measurement means. By registering it, it is possible to accurately measure the springback amount of the workpiece in the bending process, and to effectively use the measured springback amount. In addition, this bending angle measuring device is connected to the NC device via a switching means for switching between a pulse generator used when the operator manually drives in and a pulse generating means used in the automatic driving operation. Therefore, it can be easily retrofitted to a bending machine equipped with an existing NC device.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an embodiment of a bending machine to which a bending angle measuring device according to the present invention is attached.
[0026]
The bending machine 1 is, for example, a table raising type press brake equipped with an NC device, and an appropriate punch 5 suitable for processing is mounted on a punch holder provided on the upper table 3, while the lower table An appropriate die 9 corresponding to the punch 5 is mounted on the die holder provided in 7. And, by pressing the work held by the operator in a state of being put on the die 9 and hitting the abutting plate between the punch 5 and the die 7 as the lower table 7 is raised, It is comprised so that the pressurization area | region of a workpiece | work may be bent.
[0027]
The NC device includes an NC control box 11 attached to the processing machine main body, and an NC console 13 called an NC pendant that is attached to the processing machine main body so as to be easily operated by the operator.
[0028]
As shown in FIG. 5, the NC console 13 is input and set with various attributes and machining conditions such as workpiece material, plate thickness, target angle, punch tip R, die width and the like necessary for executing bending. An operation unit 15 having a keyboard and a display, an input / output unit 17, and an angle / D value conversion processing unit that converts the set target angle into an ascending stroke amount of the lower table 7, that is, a D value (depth value). And a control unit 19 having the functions as described above. Then, based on the calculated D value, a servo unit (not shown) is provided in the NC control box 11 so as to bend the workpiece to the vicinity of the target angle by raising the lower table 7 to the target height by hydraulic pressure or a motor. It has been.
[0029]
The NC console 13 is also provided with a hand pulser 21 that is operated by an operator as needed to drive the workpiece after bending (increment the bending). The hand pulser 21 is, for example, 0.01 mm per pulse. It is set to raise the lower table 7 in register. Further, a foot pedal 23 is connected to the NC console 13 for stepping operation when the operator starts and ends the bending process.
[0030]
The bending machine 1 is provided with a bending angle measurement system called a bending indicator (BI) 31. As shown in FIGS. 1 and 5, the bending indicator 31 includes an angle measuring device called a sensor unit 41 that measures the bending angle of the workpiece being pressed, and the bending angle of the workpiece removed from the processing machine body. Two types of angle measuring devices, an angle measuring device called a digital pro (digital protector) 71 for measuring, are provided. The bending indicator 31 also includes an operation unit 81 and a BI control unit 91. The sensor unit 41 is connected to the BI control unit 91, while the digital processor 71 is connected to the BI control unit 91 via the operation unit 81. The BI control unit 91 is connected to the NC console 13.
[0031]
As shown in FIG. 2, the sensor unit 41 moves to the left and right (X direction) along a guide rail 43 provided in parallel with the die 9 in front of the lower table 7 of the processing machine body. A movable body 45 that can be positioned at an arbitrary position, an elevator body 47 that moves up and down (Z direction) from the movable body 45, and a front and rear body (Y direction) that can be positioned at an arbitrary height. And a sensor support 49 that can be positioned at an arbitrary position, and a sensor head 51 that is supported by the sensor support 49 so as to be swingable around a support axis parallel to the die 9 (direction E). Thus, the sensor head 51 can be positioned at the optimum measurement position for measuring the bending angle of the workpiece being pressed.
[0032]
As shown in FIGS. 3 and 5, the sensor head 51 has optical sensors 55a and 55b using two phototransistors sandwiching a projector 53 using one laser diode that emits a laser beam that irradiates the workpiece. However, both optical sensors 55a and 55b are arranged so that the optical axis on which the laser beam reflected by the workpiece is incident is close to the optical axis of the projector 53. Are arranged so as to be inclined at the same angle, so that the bisector of the angle formed by both incident optical axes coincides with the optical axis of the projector 53. As the sensor head 51 swings in the E direction, the laser beam emitted from the projector 53 can follow the workpiece and take an arbitrary elevation angle from the horizontal.
[0033]
As shown in FIG. 5, the sensor support 49 is provided with a stepping motor 57 that can arbitrarily adjust the elevation angle of the sensor head 51, and a rotary encoder that detects the elevation angle of the sensor head 51 in conjunction with the stepping motor 57. 59 is provided. While the sensor head 51 is scanned within a predetermined angle range by the stepping motor 57, the light intensity of the laser beam reflected from the workpiece is measured by each of the optical sensors 55a and 55b, and the elevation angle of the sensor head 51 during the scan is measured. The BI control unit 91 calculates the bending angle of the workpiece based on the elevation angle detected by the rotary encoder 59 and when the light intensity shows a peak.
[0034]
That is, as shown in FIG. 3 and FIG. 4, the light intensity signal Pa of the optical sensor 55 a has a peak that is a bisector of the angle formed by the incident optical axis of the optical sensor 55 a and the optical axis of the projector 53. Coincides with the normal line of the workpiece, and the light intensity signal Pb of the optical sensor 55b shows a peak of the angle 2 between the incident optical axis of the optical sensor 55b and the optical axis of the projector 53. Since the bisector coincides with the normal of the workpiece, when the elevation angle of the sensor head 51 is a bisection angle between the elevation angle in the former and the elevation angle in the latter, the elevation angle of the sensor head 51, that is, the projector 53. The optical axis of this corresponds to the normal line of the workpiece.
[0035]
Therefore, the BI control unit 91 samples the light intensity signals Pa and Pb measured by the two optical sensors 55a and 55b and the elevation angle θ of the sensor head 51 detected by the rotary encoder 59 during scanning of the sensor head 51. Then, from the elevation angle θa when the light intensity signal Pa exhibits a peak value and the elevation angle θb when the light intensity signal Pb exhibits a peak value, an angle θ that bisects both elevation angles θa and θb is obtained by calculation. . Since the obtained angle θ coincides with the optical axis of the projector 53, it can be seen that the calculated angle θ is equal to the bending angle θ for one side of the workpiece, and the BI control unit 91 can be added by doubling the obtained angle. The bending angle 2θ of the workpiece under pressure is calculated.
[0036]
Further, the sensor unit 41 is provided with a mode changeover switch 61 that can select either the automatic follow-up mode or the manual follow-up mode. It is configured to be able to switch from a non-selected state to either selected state.
[0037]
As described above, since the mode changeover switch 61 is provided in the sensor unit 41 arranged in front of the bending machine 1, the operator can perform the operation within the bending work area and once the work is started. The automatic / manual switching can be selected as desired. In other words, even if you start the work with neither selected, you can select either the automatic driving mode or manual driving mode during the work, and you have selected the automatic driving mode before starting the work. Even after starting work in the state, you can switch to manual follow-up mode during work and select it, and even after starting work with manual follow-up mode selected before starting work, This can be selected by switching to the automatic tracking mode.
[0038]
On the other hand, the DigiPro 71 includes a reference surface 73 for angle measurement and a measurement surface 75 that can freely change the angle formed by the reference surface 73, and a position where the angle of the workpiece removed from the processing machine body is to be measured. The reference surface 73 and the measurement surface 75 coincide with the bending angle of the workpiece by causing the reference surface 73 to be in close contact with one side and the measurement surface 75 to follow the other side so that the measurement surface 75 is in close contact with the other side. The angle formed by The angle formed by the measurement surface 75 with respect to the reference surface 73 is measured by a magnetic measuring instrument called a magnescale as the amount of angular movement from the origin, and the measured value is displayed on the display 77 as an angle. .
[0039]
The operation unit 81 includes a keyboard 83 and a display 85. On the keyboard 83, in addition to the origin key used when setting the origin of the sensor unit 41 and the digital processor 71, the numeric keypad and setting key for inputting the target angle, the spring back, etc. to the sensor unit 41, the automatic operation of the sensor unit 41 Various necessary keys are provided such as an automatic key for selecting the driving mode, a manual key for selecting the manual driving mode, and the like. Further, the display unit 85 is provided with a process display unit 87 for displaying a process number or a mode type, and a data display unit 89 for displaying an input set value by an operator such as a target angle and a springback.
[0040]
Then, the angle measurement value of the sensor unit 41 is displayed on the data display unit 89 together with the display on the process display unit 87, and the angle measurement value of the digital processor 71 is displayed on the process display unit 87 with the display indicating that. Are displayed on the data display unit 89.
[0041]
The BI control unit 91 is provided with a control unit 93 having a function as an arithmetic processing unit for calculating the bending angle of the workpiece being pressed by the sensor unit 41 and an input / output unit 95. Also has a function as an arithmetic processing unit that calculates an angle error between the measured bending angle and the target angle by the sensor unit 41 and converts the angle error into a corresponding D value (depth value). The BI control unit 91 also includes a pulse generator 96 used in the automatic driving mode, and a switch 97 for using the pulse generator 96 in place of the hand pulser 21 of the NC console 13 in the automatic driving mode. The BI control unit 91 is connected to the NC console 13 via the switch 97, and therefore, the bending indicator 31 is connected to the NC device.
[0042]
That is, in order to connect the BI control unit 91 to the NC console 13, the connection connected to the input / output unit 17 of the NC console 13 is disconnected from the hand pulser 21, and it is connected to the side opposite to the pulse generator 96 of the switch 97. In addition, the common terminal of the switch 97 is connected to the connector of the input / output unit 17 to which the hand pulser 21 is connected. It is only necessary to make a connection for transmitting a BI start signal from the NC console 13 to the BI control unit 91 and a connection for transmitting a stop signal from the BI control unit 91 to the NC console 13.
[0043]
As described above, the operation for connecting the BI control unit 91 to the NC console 13 is very simple, and it is not necessary to substantially modify the NC console 13, so that it can be easily retrofitted to the existing NC console 13. Can do. As a result, the bending indicator 31 can be easily retrofitted to a bending machine equipped with an existing NC device.
[0044]
The bending indicator 31, particularly the sensor unit 41, the operation unit 81 and the BI control unit 91, functions as a driving control system in the automatic driving mode and also functions as a driving measurement system in the manual driving mode.
[0045]
In addition, the BI control unit 91 is provided with a buzzer 99 for notifying the operator of the bending angle of the workpiece during sounding operation by sound, and this buzzer 99 is provided at the end of bending by the NC device. When the measured value corresponds to the target angle, a bending end sound is generated to inform the operator of this, and when the measured value of the workpiece bending angle exceeds the target angle, a warning sound is sent to warn the operator of that. When there is an angle error that occurs and the measured value of the bending angle of the workpiece does not reach the target angle, a driving operation sound that informs the operator during the driving operation that is executed by the driving stroke amount corresponding to the angle error And the operator is informed when the end of the stroke reaches the end of the stroke. Is made as to generate an end sound narrowing have.
[0046]
Here, the origin setting of the sensor unit 41 will be described. The sensor unit 41 has the origin when the optical axis of the projector 53 is horizontal. For this reason, a magnet seal is attached to a predetermined position on the surface facing the front of the die 9 mounted on the die holder, and the origin key of the operation unit 81 is pressed to scan the sensor head 51 against the magnet seal forming the vertical surface. This is done by pressing for a certain time. Then, the bisector (that is, horizontal) of the peak values of the two light sensors 55a and 55b at that time is registered as the origin.
[0047]
The origin of the digital controller 71 is determined by pressing the origin key of the operation unit 81 for a certain period of time while the reference surface 73 and the measurement surface 75 of the digital processor 71 are in close contact with a right angle measuring tool such as a square. Then, the magnetic measurement value (that is, right angle) at that time is registered as the origin.
[0048]
Next, the effect | action of said embodiment is demonstrated using the flowchart shown to FIGS.
[0049]
First, a test piece made of the same material and thickness as the workpiece and thickness of the workpiece to be bent is prepared. As long as the material and thickness of the test piece are the same as those of the workpiece, the size of the test piece does not need to be the same as that of the workpiece, and an appropriate size that can be easily handled can be selected. Although such a test piece is not a workpiece, it functions in the same manner as a workpiece only for the purpose of measuring springback, and will be referred to as a workpiece hereinafter.
[0050]
Further, a punch 5 having a predetermined tip R is mounted on the punch holder of the bending machine 1, while a die 9 having a predetermined die width is mounted on the die holder. Then, a required bending angle is input to the NC console 13 and the operation unit 81.
[0051]
That is, assuming that the target angle S is 90 °, for example, as shown in FIG. 6, the operator first inputs the target angle S (S = 90 °) into the operation unit 81 and inputs to the NC console 13. A temporary bending angle P (P = 92 °) that is slightly (2 to 3 °) less than the target angle S is input by key input (step S1). In response to this, the control unit 19 of the NC console 13 converts the temporary bending angle P into a D value corresponding thereto.
[0052]
Next, the operator presses the NC start button of the NC console 13, sets the work at a predetermined position of the processing machine body, and then steps on the foot pedal 23 (step S2).
[0053]
When the NC start button is pressed, the NC is set to the automatic operation mode, the NC starts automatic operation, and executes bending according to the programmed process (step S3).
[0054]
When the lower table 7 is raised and reaches the rising end of provisional bending (step S4), the NC automatically stops operation (step S5).
[0055]
At this time, the bending angle of the workpiece is within a range of an arbitrary error (for example, ± 2 °) from the set temporary bending angle P (P = 92 °). Further, when the automatic stop is performed, the NC remains in the automatic operation mode and is in an interlocked state in which the D value cannot be corrected.
[0056]
When the NC stops operation, the NC console 13 sends a BI start signal to the BI control unit 91 (step S6). In response to this, the bending indicator 31 is turned on.
[0057]
First, the sensor unit 41 measures the bending angle of the workpiece, and displays the angle measurement value Pδ (near the temporary bending angle P including an error) on the display 85 of the operation unit 81 via the BI control unit 91. (Step S7).
[0058]
Here, it is determined whether or not the measured bending angle Pδ corresponds to the target angle S (matches or falls within the allowable range) (step S8). (Step S9), and in the case of insufficient bending, it is determined whether the automatic driving mode is set or the manual driving mode is set (step S10).
[0059]
When the measured bending angle Pδ corresponds to the target angle S (Pδ = S), the buzzer 99 of the BI control unit 91 generates an appropriate bending end sound to notify the operator of this (step S11). Thereby, the operator can know by ear that the bending angle of the workpiece corresponds to the target angle S.
[0060]
Therefore, the operator releases the foot that was stepping on the foot pedal 23 (step S12).
[0061]
Then, the NC console 13 stops sending a BI start signal to the BI control unit 91 (step S13). In response to this, the bending indicator 31 is turned off. This completes the bending.
[0062]
The bending angle of the workpiece in the final pressure state when this bending is finished is an angle S corresponding to (matching or within an allowable range) the target angle S. ^* (S ^* = 90 °) and the angle value S ^* (S ^* = 90 °) is stored in the control unit 93 of the BI control unit 91.
[0063]
When the measured bending angle Pδ is excessively bent (Pδ <S), as shown in FIG. 7, the buzzer 99 of the BI control unit 91 generates an appropriate warning sound to warn the operator (step). S21). As a result, the operator can surely know by ear that the bending angle of the workpiece exceeds the target angle S and is excessively bent.
[0064]
The operator who has heard the warning sound releases the foot that has stepped on the foot pedal 23 (step S22).
[0065]
Then, the NC console 13 stops sending a BI start signal to the BI control unit 91 (step S23). In response to this, the bending indicator 31 is turned off.
[0066]
Therefore, the workpiece is replaced with a new one, and the provisional bending angle P is reset (step S24). That is, for example, a new temporary bending angle is set to Q (Q = 93 to 94 °). Thereafter, returning to {circle around (2)} in FIG. 6, the operations after step S <b> 2 are performed.
[0067]
When the measured bending angle Pδ is insufficient bending (Pδ> S), if the automatic driving mode is set, the BI control unit 91 first sends a stop signal to the NC console 13 as shown in FIG. (Step S31). In response, the NC is released from the set automatic operation mode, the D value correction interlock is released, and the D value can be corrected.
[0068]
Next, the BI control unit 91 calculates an angle error δ (δ = Pδ−S) between the measured bending angle Pδ and the target angle S, and converts the angle error δ into a corresponding D value (step S32). .
[0069]
Then, the BI control unit 91 switches the switch 97 to the pulse generator 96 side (step S33), and generates a number of pulses corresponding to the D value from the pulse generator 96 (step S34).
[0070]
As a result, the bending indicator 31 causes the NC to execute an automatic driving operation (step S35), and during that time, the buzzer 99 of the BI control unit 91 generates an appropriate driving operation sound to inform the operator of this (step S36). . As a result, the operator can know by ear that the automatic driving operation is being performed.
[0071]
During this automatic driving operation, the sensor unit 41 measures the bending angle of the workpiece at an appropriate interval, and displays the measured angle value on the display unit 85 of the operation unit 81 via the BI control unit 91 (step S37). .
[0072]
When the measured bending angle becomes an angle corresponding to the target angle S (coincidence or within an allowable range) (step S38), based on the angle measurement value transmitted from the sensor unit 41, the BI control unit 91 outputs from the pulse generator 96 The generation of pulses is stopped (step S39), and the buzzer 99 generates an appropriate driving end sound that informs the operator that the angle corresponding to the target angle S has been reached (step S40). Thereby, the operator can know by ear that the bending angle of the workpiece has become an angle corresponding to the target angle S.
[0073]
Therefore, the operator releases the foot that was stepping on the foot pedal 23 (step S41).
[0074]
Then, the NC console 13 stops sending a BI start signal to the BI control unit 91 (step S42). In response to this, the bending indicator 31 is turned off. This completes the bending.
[0075]
The bending angle of the workpiece in the final pressure state when this bending is finished is an angle S corresponding to (matching or within an allowable range) the target angle S. ^* (S ^* = 90 °) and the angle value S ^* (S ^* = 90 °) is stored in the control unit 93 of the BI control unit 91.
[0076]
FIG. 9 shows the above-described steps S34 to S38 in more detail. That is, the BI control unit 91 generates a predetermined number of pulses (for example, 10 pulses) as an initial value from the pulse generator 96, and thereby the bending indicator 31 causes the NC to perform an initial driving operation ( Step S51).
[0077]
During this initial pulse generation period, the buzzer 99 of the BI control unit 91 generates an appropriate driving sound for notifying the operator of this (step S52). Thus, the operator can surely know by the ear that the driving operation is being performed.
[0078]
When the generation of the initial pulse is finished, the sensor unit 41 measures the bending angle of the workpiece and displays the measured angle value on the display unit 85 of the operation unit 81 via the BI control unit 91 (step S53). The BI control unit 91 calculates a D value (D1) per pulse from the angle measurement value at that time and the initial pulse number (ie, 10 pulses) (step S54).
[0079]
Subsequently, the BI control unit 91 calculates the remaining D value (Dn) based on the obtained D value (D1) per pulse (step S55).
[0080]
Then, the BI control unit 91 generates a number of pulses (n pulses) corresponding to the D value (Dn) from the pulse generator 96, whereby the bending indicator 31 causes the NC to perform an automatic driving operation ( Step S56).
[0081]
During the n pulse generation period, the buzzer 99 of the BI control unit 91 generates an appropriate driving sound for notifying the operator of this (step S57). As a result, the operator can know by ear that the automatic driving operation is being performed.
[0082]
When the generation of n pulses is finished, the sensor unit 41 measures the bending angle of the workpiece, and displays the measured angle value on the display unit 85 of the operation unit 81 via the BI control unit 91 (step S58). The BI control unit 91 determines whether or not the angle measurement value at that time has reached the target angle S (step S59). If the target angle S has not been reached, the remaining D value (Dn) is calculated again. The process returns to step S55.
[0083]
That is, starting from the calculation of the remaining D value (Dn), a series of operations ranging from execution of automatic driving operation based on the D value (Dn), generation of driving noise during execution, measurement of workpiece bending angle, and display are performed. By repeating the operation several times, the target angle S can be accurately driven.
[0084]
On the other hand, when the measured bending angle Pδ is insufficiently bent (Pδ> S) and the manual driving mode is set, the operator is displayed on the display unit 85 of the operation unit 81 as shown in FIG. The angle measurement value Pδ is checked to confirm that the driving is necessary, and then the NC stop button is pressed (step S61). When the NC stop button is pressed, the NC is released from the set automatic operation mode, the D value correction interlock is released, and the D value can be corrected.
[0085]
Next, the operator operates the hand pulser 21 while looking at the display angle, and manually performs the follow-up operation (step S62).
[0086]
During the manual driving operation, the sensor unit 41 measures the bending angle of the workpiece, and displays the measured angle value on the display unit 85 of the operation unit 81 via the BI control unit 91 (step S63).
[0087]
When the measured bending angle is equal to (or coincides with or within an allowable range) the target angle S (step S64), the buzzer 99 of the BI control unit 91 generates an appropriate driving end sound to notify the operator (step S64). S65). Thereby, the operator can know by ear that the bending angle of the workpiece has become an angle corresponding to the target angle S.
[0088]
Therefore, the operator releases the foot that was stepping on the foot pedal 23 (step S66).
[0089]
Then, the NC console 13 stops sending a BI start signal to the BI control unit 91 (step S67). In response to this, the bending indicator 31 is turned off. This completes the bending.
[0090]
The bending angle of the workpiece in the final pressure state when this bending is finished is an angle S corresponding to (matching or within an allowable range) the target angle S. ^* (S ^* = 90 °) and the angle value S ^* (S ^* = 90 °) is stored in the control unit 93 of the BI control unit 91.
[0091]
When the necessary bending process is completed in this way, the work is first removed from the processing machine body as shown in FIG. 11 (step S71). Then, the workpiece is detached from the punch 5 and the die 9 and becomes completely unloaded, and the bending angle is slightly opened by the spring back. That is, the angle S at the end of bending ^* (S ^* = 90 °), the angle F is increased by the amount corresponding to the springback (for example, F = 91 ° 20 ′).
[0092]
Next, an operator measures the bending angle of a workpiece | work using the digital processor 71 (step S72).
[0093]
Then, the angle measurement value F (F = 91 ° 20 ′) is displayed on the display 77 of the digital processor 71 and also displayed on the display 85 of the operation unit 81 (step S73). In other words, the operation unit 81 displays that the digital display is being used on the process display unit 87 of the display unit 85 and displays the angle measurement value F (F = 91 ° 20 ′) on the data display unit 89. From this, the operator can know that the bending angle of the workpiece spread by the springback is F (F = 91 ° 20 ′).
[0094]
Next, the operator presses the spring back key of the operation unit 81 (step S74).
[0095]
Then, the control unit 93 of the BI control unit 91 makes the bending angle S in the final pressurized state. ^* (S ^* = 90 °) and the bending angle F (F = 91 ° 20 ′) in the no-load state, the springback amount B (B = 1 ° 20 ′) is calculated and obtained. While displaying on the display part 89, it memorize | stores and registers in the memory | storage part of the control part 93 (step S75). By looking at this display, the operator can accurately know the springback amount B (B = 1 ° 20 ′) without calculating it himself.
[0096]
When bending using an actual work, the target pressure S (S = 90 °) is obtained by weaving the springback amount B (B = 1 ° 20 ′) into the target pressure S (S = 90 °). 88.degree. 40 '), and this target pressurization angle A (A = 88.degree. 40') is key-inputted to the operation unit 81, while the temporary bending angle P (P.sub.3) which is slightly (2-3.degree.) Sweeter than the target angle S. = 92 °) may be input to the NC console 13 and the same operation as described above may be performed.
[0097]
In addition, the target pressure angle A (A = 88 ° 40 ′) can be determined by incorporating the springback amount B (B = 1 ° 20 ′) into the target angle S (S = 90 °). Since the control unit 93 executes, the operator only has to input the target angle S (S = 90 °) and the springback amount B (B = 1 ° 20 ′) into the operation unit 81 by both keys. Based on the above, the control unit 93 of the BI control unit 91 automatically calculates and obtains the target pressurization angle A (A = 88 ° 40 ′).
[0098]
As described above, when this bending angle measuring device is used, the measurement of the springback is completed, and at the same time, the data can be stored in the BI control unit 91. Suitable for repeated use when processing.
[0099]
In addition, even if not all of the workpieces that need to be processed, even if it is not just before processing, if there is a test piece or sample workpiece, the spring back is measured in advance and the data is sent to the BI control unit 91. Since it can be registered, it is possible to execute the measurement and registration work of the springback in a time interval between the machining times, so that the work schedule can be given a degree of freedom.
[0100]
In the above-described embodiment, the sensor head 51 includes the projector 53 using one laser diode and the optical sensors 55a and 55b using two phototransistors, and the sensor head 51 is configured at a predetermined angle. While scanning within the range, the light intensity of the laser beam reflected from the workpiece is measured by each optical sensor, and the elevation angle of the sensor head 51 during the scan is detected, and based on the elevation angle when the light intensity shows a peak. Although it is configured to calculate the bending angle of the workpiece, it is not limited to this. For example, an appropriate non-contact type sensor unit can be used, and a contact type can also be used. is there.
[0101]
In the above embodiment, when a temporary bending angle is key-inputted to the NC console 13, the control unit 19 of the NC console 13 serves as an angle / D value conversion processing unit that converts the temporary bending angle into a D value corresponding thereto. Although the present invention is applied to an NC apparatus having a function, the present invention is not limited to this. For example, the present invention can also be applied to an NC apparatus having a structure in which an operator directly inputs a D value.
[0102]
In the above embodiment, the workpiece is bent to the target bending angle by the NC device and then driven to the target angle. However, the present invention is not limited to this. For example, the NC device is bent from the beginning to the target angle. You may comprise as follows. In that case, even if the bending angle of the workpiece is deviated from the target angle, the amount of springback can be obtained by taking the difference from the bending angle when the workpiece is in an unloaded state.
[0103]
In the above-described embodiment, the present invention is applied to a bending machine provided with an NC device. However, the present invention is not limited to this. For example, the present invention can also be applied to a bending machine that bends with a handle.
[0104]
Furthermore, in the above embodiment, the table raising type press brake is exemplified as the bending machine, but the invention is not limited to this, and for example, it is applied to various bending machines including a table lowering type press brake. It is possible.
[0105]
【The invention's effect】
As described above, the present invention eliminates the step of pressurizing the workpiece to the vicinity of the target angle by the bending machine, the step of measuring the bending angle of the workpiece at the final pressurization and holding the measured value, and the pressurization. Both using the step of placing the workpiece in an unloaded state, the step of measuring the bending angle of the workpiece in an unloaded state and holding the measured value, and the final pressure angle measured value and the unloaded angle measured value. Since the process consists of a step of obtaining the angle difference of the workpiece and a step of registering the obtained angle difference as a springback amount, the springback amount of the workpiece in bending can be accurately measured, and the measured spring The back amount can be used effectively, thereby improving the workpiece finishing accuracy.
[0106]
The present invention also includes a step of pressurizing the workpiece to the vicinity of the target angle by the NC device, a step of measuring the bending angle of the workpiece at the final pressurization and holding the measured value, and removing the workpiece from the bending machine. Using the load process, measuring the bending angle of the unloaded workpiece and holding the measured value, and using the final pressurization angle measurement value and the no-load angle measurement value, Since it is composed of a process to obtain and a process to register the obtained angle difference as a springback amount, it is possible to accurately measure the springback amount of the workpiece in bending, and the measured springback amount is effective. Therefore, there is an effect that the finishing accuracy of the workpiece can be improved.
[0107]
Further, the present invention provides a driving control means, a step of setting a target angle in the driving control means, a step of setting a D value corresponding to a provisional bending angle smaller than the target angle in the NC device, and a work by the NC device. Based on the angle error between the angle measurement value and the target angle, the drive control means automatically drives into the NC unit based on the process of pressurizing and bending to near the temporary bending angle, the process of measuring the bending angle of the workpiece at the end of the temporary bending A driving process for transferring the number of pulses necessary to execute the operation to drive the workpiece to the target angle, a final pressurization angle measurement process for measuring the bending angle of the work at the end of the driving, and a work after removing the pressure From the difference between the process of making the unloaded state, the unloaded angle measuring process of measuring the bending angle of the unloaded workpiece, Since it has a structure consisting of a step for obtaining the springback amount and a step for registering the obtained springback amount, the springback amount of the workpiece in bending can be accurately measured, and the measured springback amount can be calculated. It can be used effectively, thereby improving the workpiece finishing accuracy.
[0108]
The present invention also includes a step of providing a follow-up measuring means, setting a target angle in the follow-up measuring means, a step of setting a D value corresponding to a provisional bending angle that is less than the target angle in the NC device, and a work by the NC device. A step of pressurizing and bending to near the temporary bending angle; and a step of measuring the bending angle of the workpiece and displaying the measured value during the manual driving operation by the operation of the pulse generator following the temporary bending; and When the angle measurement value becomes an angle corresponding to the target angle, the follow-up measurement means holds the measurement angle at that time as the final pressurization angle measurement value, and removes the pressurization to make the workpiece unloaded. Using the process, the step of measuring the bending angle of the unloaded workpiece and holding the measured value, and the final pressure angle measured value and the unloaded angle measured value, the spring back amount of the workpiece is determined. And the process of registering the calculated springback amount, it is possible to accurately measure the springback amount of the workpiece in bending, and effectively use the measured springback amount. Thus, there is an effect that the finishing accuracy of the workpiece can be improved.
[0109]
In addition, the present invention provides an NC device after the work is bent to the vicinity of the temporary bending angle by the operating means for setting the target angle and the NC device for which the D value corresponding to the temporary bending angle that is less than the target angle is set. A pulse generator that generates the number of pulses required to execute the automatic driving operation for driving the workpiece to the target angle, and the NC device performs the automatic driving operation using the pulses transferred from the pulse generating device. When the bending angle reaches an angle corresponding to the target angle, a pressure angle measuring means for measuring the angle, a no-load angle measuring means for measuring the bending angle of the unloaded workpiece after the pressure is removed, The springback amount is obtained from the difference between the final pressure measurement value of the workpiece by the pressure angle measurement means and the no-load angle measurement value of the work by the no-load angle measurement means. Since it is configured to have a control means to be registered, it is possible to accurately measure the amount of spring back of the workpiece in bending, and to effectively use the measured amount of spring back, thereby finishing the workpiece. There is an effect that accuracy can be improved.
[0110]
Further, the present invention provides the pulse generation after the work is bent to the vicinity of the temporary bending angle by the operating means for setting the target angle and the NC device for setting the D value corresponding to the temporary bending angle that is less than the target angle. During the manual driving operation to drive the workpiece to the target angle by operating the instrument, the pressure angle measuring means for measuring the bending angle of the workpiece, the means for displaying the angle measurement value by the pressure angle measuring means, No-load angle measuring means for measuring the bending angle of the workpiece in the no-load state after the pressure is removed, the final pressurization angle measurement value by the pressurization angle measurement means at the end of manual driving, and no load by the no-load angle measurement means Since it is configured to have a control means that calculates the springback amount from the difference from the angle measurement value and registers it, the springback amount of the workpiece in bending work It can be accurately measured, moreover, it is possible to effectively utilize the measured amount of spring back, thereby there is an effect that it is possible to improve the finishing precision of the workpiece.
[0111]
Furthermore, the present invention provides a workpiece near a temporary bending angle by an operating means for setting a target angle, a pulse generating means for automatic driving, and an NC device for setting a D value corresponding to a temporary bending angle that is less than the target angle. After the bending operation, the NC device drives the workpiece to the target angle based on the applied pulse. During the driving operation, the pressure angle measuring means for measuring the bending angle of the workpiece, and after the driving is finished, the pressure is removed. The difference between the no-load angle measurement means that measures the bending angle of the unloaded workpiece, the final pressurization angle measurement value by the pressurization angle measurement means at the end of driving, and the no-load angle measurement value by the no-load angle measurement means From the control means for obtaining the springback amount and registering it, and the pulse generation source applied to the NC device to either the pulse generator or the pulse generation means Switching means that can be connected to the NC unit via this switching means, so that the spring back amount of the workpiece in bending can be accurately measured, and the measured spring back amount is effective. Therefore, there is an effect that the finishing accuracy of the workpiece can be improved.
[0112]
In addition, this bending angle measuring device is connected to the NC device via a switching means for switching between a pulse generator used when the operator manually drives in and a pulse generating means used in the automatic driving operation. Can be easily connected to an NC device, and can be easily retrofitted to a bending machine equipped with an existing NC device. As a result, it is extremely suitable as a retrofitting bending angle measuring device. There is.
[Brief description of the drawings]
FIG. 1 is a perspective view of a bending machine to which a bending angle measuring device is attached.
FIG. 2 is a perspective view of a sensor unit.
FIG. 3 is an explanatory diagram of the principle of angle measurement by a sensor head.
FIG. 4 is a graph showing the relationship between the elevation angle of the sensor head and the light intensity of the optical sensor.
FIG. 5 is a system block diagram of a bending angle measuring apparatus.
FIG. 6 is a flowchart showing the operation of the bending angle measuring apparatus.
FIG. 7 is a flowchart in the case of excessive bending.
FIG. 8 is a flowchart in the case of insufficient bending.
FIG. 9 is a detailed flowchart of a part of FIG. 8;
FIG. 10 is a flowchart in a manual driving mode.
FIG. 11 is a flowchart for obtaining springback.
[Explanation of symbols]
1 Bending machine (press brake)
3 Upper table
5 Punch
7 Lower table
9 die
11 NC control box
13 NC console
15 Operation unit
17 Input / output section
19 Control section
21 Hand Pulser
23 Foot pedal
31 Bending indicator (BI)
41 Sensor unit
43 Guide rail
45 Mobile
47 Lifting body
49 Sensor support
51 Sensor head
53 Floodlight
55a, 55b Optical sensor
57 Stepping motor
59 Rotary encoder
61 Mode selector switch
71 DigiPro (digital protector)
73 Reference plane
75 Measuring surface
77 Display
81 Operation unit
83 keyboard
85 Display
87 Process display
89 Data display section
91 BI control unit
93 Control section
95 I / O section
96 Pulse generator
97 selector
99 buzzer

Claims (2)

In bending machine equipped with NC device,
Providing a driving control means, and setting a target angle in the driving control means;
Setting a D value corresponding to a temporary bending angle that is sweeter than the target angle in the NC device;
A process of pressurizing the workpiece by the NC device and bending it to the vicinity of the temporary bending angle;
Measuring the bending angle of the workpiece at the end of provisional bending;
Based on the angle error between the angle measurement value and the target angle, a driving step for driving the workpiece to the target angle by transferring the number of pulses required for the driving control means to cause the NC device to perform an automatic driving operation;
A final pressurization angle measurement process that measures the bending angle of the workpiece at the end of the driving,
Removing the pressure and bringing the workpiece into an unloaded state;
A no-load angle measurement process for measuring the bending angle of the unloaded workpiece;
A step of determining the amount of spring back of the workpiece from the difference between the final pressure angle measurement value and the no-load angle measurement value;
And a step of registering the obtained springback amount.
The driving-in step is
Transferring a predetermined number of pulses as an initial value to the NC device to execute an initial driving operation;
Measuring the bending angle of the workpiece at the end of the initial driving operation;
Obtaining a D value per pulse from the angle measurement value at the end of the initial driving operation and the number of pulses of the initial value, and obtaining the remaining D value based thereon;
A method for measuring a bending angle in a bending machine, comprising: transferring a number of pulses corresponding to the obtained remaining D value to an NC apparatus to execute a remaining driving operation for driving a workpiece to a target angle. . In bending machine equipped with NC device,
An operation means for setting a target angle;
Necessary for causing the NC device to perform an automatic driving operation for driving the workpiece to the target angle after the workpiece is bent to the vicinity of the temporary bending angle by the NC device in which the D value corresponding to the temporary bending angle that is less than the target angle is set. Pulse generating means for generating a large number of pulses;
A pressure angle measuring means that measures the angle of the workpiece when the bending angle of the workpiece reaches an angle corresponding to a target angle by performing an automatic driving operation by the NC device using a pulse transferred from the pulse generating means;
A no-load angle measuring means for measuring a bending angle of a workpiece in an unloaded state after the pressure is removed;
From the difference between the final pressure angle measurement value of the workpiece by the pressure angle measurement means and the no load angle measurement value of the work by the no load angle measurement means, a control means for obtaining a springback amount and registering it, With
The pressurization angle measuring means measures the bending angle of the workpiece at the end of the temporary bending by the NC apparatus, and the control means performs an automatic driving operation to the NC apparatus based on the angle error between the angle measurement value and the target angle. A number of pulses required to be executed are generated from the pulse generating means,
The control means first generates a predetermined number of pulses as an initial value from the pulse generation means, performs an initial driving operation by the NC device, calculates a D value per pulse, and calculates this one pulse A bending angle in a bending machine characterized in that the number of pulses necessary for executing the remaining driving operation is calculated based on the perceived D value, and that number of pulses is generated from the pulse generating means. measuring device.

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