JPH012722A - bending machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a bending angle sensor that detects the bending angle of a workpiece that is bent by a bending machine such as a breath brake. Regarding molds.

(Prior art) Conventionally, when bending a workpiece using a bending machine such as a breath brake, in order to obtain the desired bending angle on the workpiece, the bending operation must be repeated several times, and the upper mold I had to adjust the distance between the mold and the lower mold. Such adjustments require a lot of time and effort, and often rely on the experience and intuition of the operator, which has been a major obstacle to improving work efficiency.

Therefore, devices that automatically detect this bending angle have been developed, and devices that use reflected light or image processing are known so far.

(Problems to be Solved by the Invention) However, the previously known bending angle detection devices using reflected light or image processing have detection errors in the bending angle, and are still insufficient in reliability and high accuracy. It was not possible to obtain a suitable bending angle.

SUMMARY OF THE INVENTION An object of the present invention is to provide a mold equipped with a bending angle sensor that detects bending angles with high accuracy and improves the efficiency of bending processing, in order to improve the above-mentioned problems.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a plurality of capacitive bending angle sensors on at least one of the upper mold or the lower mold that bends the workpiece, Each sensor was provided extending in the direction along the bending line of the workpiece, and was also arranged in parallel to form a mold equipped with a bending angle sensor.

(Function) By inventing a mold equipped with the bending angle sensor of the present invention, at least one workpiece that is bent from the surface of the capacitive sensor provided on at least one of the upper mold or the lower mold can be By detecting the distance to the two points, an accurate bending angle can be obtained with good accuracy. Therefore, by utilizing this bending angle, the efficiency of the bending process can be improved.

(Example) Hereinafter, an example of Akira Honmuro will be described in detail based on the drawings.

Referring to FIG. 1, a C-shaped side frame 3 in a breath brake 1 which is an example of a bending machine is shown.
R. A lower frame 5 is provided at the lower part of 3L. A die 9 serving as a lower die is mounted on the lower frame 5 via a lower die holder 7 so as to extend in the left-right direction in FIG.

Note: Side frame 3R. An upper frame 11 is attached to the upper part of the upper frame 13, and fluid pressure cylinders 13R. 13L is provided.

The fluid pressure cylinder 13R. 13L piston rod 1
5R. A ram 17 is connected to 15L. Fluid pressure cylinder 13R. The piston rod 15 is activated by the operation of 13L.
R. The ram 17 is moved up and down via the shaft 15L.

A punch 21 as an upper die is attached to the lower part of the ram 17 via an upper die holder 19, and the punch 21 is moved up and down with respect to the die 9 to punch a workpiece (not shown), for example, in a U shape.
A letter-shaped or V-shaped bending process is performed.

The punch 21 is provided with a built-in bending angle sensor 23. More specifically, as shown in FIG. 2, two sides 21A sandwiching the bending apex 21P of the punch 21
．． A guide groove 25 is formed in a direction perpendicular to one side 21A of 21B, and the bending angle sensor 23 is guided and built into the guide groove 25.

The bending angle sensor 23 includes a plurality of, for example, two capacitive sensors 23A. 23B, and the sensors 23A and 23B are arranged side by side as shown in FIG. 3, and extend in the longitudinal direction of the side 21A to provide a large capacitance. Moreover, a plurality of screw holes 27 are bored in a direction substantially perpendicular to the side 21B, and a set screw 29 is hingedly inserted into the screw holes 27, so that the bending angle sensor 23 is inserted into the punch 21. Fixed.

With the above configuration, the workpiece W is placed on the die 9 and the ram 17
The punch 21 approaches the die 9 and bending is performed by the lower part (3). Assume that a bending process is performed on the workpiece W and the workpiece W becomes a workpiece WA. That is,
The bending angle when the workpiece W is bent into the workpiece WA is θ. The inter-sensor distance between each sensor 23A and sensor 23B is ι, the angle between the punch 21A and the workpiece WA is θ1, and the angle between the double line from the bending apex 21P of the punch 21 and the side 21A is β2. Furthermore, each sensor 23A. Workpiece WA with a heavy line from the center of 23B
The intersection point is defined as the intersection point, and each sensor 23A. The distances between the center plane of 23B and the intersection point are respectively A. If B,
The following relational expression holds true.

θ=90−(θ1+θ2) β1=Arc tan(A−B/l) According to the above two equations, the bending angle θ is determined by θ=90−{θ2+Arc tan{A−B/l}}. On the other hand, since θ2 and ι are preset values, A. By measuring the distance B, the bending angle θ of the workpiece W can be determined.

In FIG. 2, the bending angle sensor 23
Although it is installed in a direction perpendicular to the side 21A, it may be installed in a direction perpendicular to the other side 21B of the punch 21 to measure the bending angle θ of the workpiece W.

Next, the capacitance type sensor 23A of the bending angle sensor 23
．． Based on the change in capacitance detected by 23B,
The configuration block diagram for determining the bending angle θ of the workpiece W is shown in the fourth figure.
Illustrated.

In FIG. 4, capacitive sensor 23A. 23Bf each A
/D converter 31A. 31B and distance A. B exchange part 33
A. It is connected to the arithmetic processing section 35 via 33B.

The calculation processing section 35 includes an angle reference setting storage section 3.
7. A distance reference setting storage unit 39 and a display unit 1 are connected.

Capacitive sensor 23A. 23B, the capacitance change with the workpiece WA is detected by the A/D converter 31A. 31B via distance A. B converter 33A. Distance A. from voltage change at 33B. It is converted to B. The transformed distance A. B is input to the arithmetic processing section 35. On the other hand, the angle reference setting storage section 3
An angle setting value θ2 stored in advance in the distance reference setting storage chamber 39 and a length setting value ι stored in advance in the distance reference setting storage room 39 are each input in advance to the arithmetic processing unit 35.

In the arithmetic processing unit 35, the following arithmetic processing is performed: θ=90−{θ2+Arctan(AB/l)}, and the bending angle θ of the workpiece W is determined.

The determined bending angle θ is transferred to the display section 41 and displayed on the display or printer.

In FIG. 2, each sensor 23A. The bending angle θ of the workpiece W can also be determined from the differential voltage based on the capacitance of the workpiece W. That is, as shown in FIG.
A. There is a proportional relationship between the differential voltage of 23B and the bending angle θ1, and the data of this relational expression is stored in the data storage unit. Each sensor 23A. 23B is extracted from the data stored in the data storage unit, and the arithmetic processing unit 35 calculates θ=90−(θ1
+θ2) and displaying the result on the display unit 41 or on a printer, the bending angle θ is determined.

A flow chart of the operation based on the embodiment shown in FIG. 2 is shown in FIG. In Figure 6, first step 4
3 in advance at θ2. Set and input ι. In step 45, a target value D for lowering the ram 17 is set and input. Next, in step 47, the bending process is started. Step 49
Then, the ram 17 descends at speed ■.

In step 51, the current position of the ram 17 is compared with the target value D. If they are not equal, the process returns to step 49, and if they are equal, the ram 17 is lowered at a slow speed in step 53. In step 55, each sensor 23A starts measuring the bending angle. A/D converter 31A.23B converts the voltage value based on the capacitance change. Convert with 31B. Step 57
Then distance A. B converter 33A. 33B and distance A.
Convert to B and measure.

In step 59, the arithmetic processing unit 35 calculates θ=90−(θ1+θ2). Arithmetic processing of θ1-Arc tan (A-B/l) is performed, and in step 61, the bending angle θ is displayed each time on the display section 41 or on a printer. In step 63, it is determined whether θ-[90-(θ1+θ2)]=0, and if it is not equal, the process returns to before step 53.
If they are equal, the process proceeds to step 65, where the ram 17 is discontinued and the process ends.

In this way, as the bending angle sensor 23, the capacitance type sensor 23A. 23B are built into the punch 21 and arranged side by side, and extend in the longitudinal direction of the side 21A, so that the bending angle θ of the workpiece W can be measured accurately and accurately. (2) As a result, the efficiency of the bending process can be improved.

It should be noted that the present invention is not limited to the above-described embodiment, but can be implemented in other forms by making appropriate changes. For example, the capacitive bending angle sensors 23A. 23B is built into the punch 21 serving as an upper die, but this capacitive bending angle sensor 23A. 23B may be built into the die 9 as the lower mold, or may be attached to the front or rear of the die 9.

[Effects of the Invention] As can be understood from the above description of the embodiments, according to the present invention, the upper mold for bending the workpiece has a plurality of capacitive bending angles on at least one of the lower molds. The sensors are provided, and each sensor is extended in the direction along the bending line of the workpiece, and is installed in parallel, so the bending angle of the workpiece can be detected accurately and precisely, resulting in highly reliable bending. Angle is obtained. As a result, the efficiency of the bending process can be improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a press brake according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view taken along line 2-2 in FIG. FIG. 3 is a perspective view of the bending angle sensor. Fourth
The figure is a configuration block diagram for detecting a bending angle using a bending angle sensor. FIG. 5 is a graph showing the relationship between the differential voltage of each sensor and the angle θ1, and FIG. 6 is a flow chart of an example of the operation of this embodiment. [Explanation of symbols representing main parts of drawings] 1...Press brake 9...Die 17...Ram 21...Punch 23...
Bending angle sensor 23A. 23B...Capacitance type sensor 35...Arithmetic processing section 41...Display section

Claims (2)

[Claims] (1) A plurality of capacitance bending angle sensors are provided on at least one of the upper die or the lower die that bends the workpiece, and each sensor is provided extending in the direction along the bending line of the workpiece and is arranged in parallel. A mold equipped with a bending angle sensor. (2) In an upper mold having two sides sandwiching the bending apex that applies bending to the workpiece, a plurality of capacitive bending angle sensors are installed in a direction perpendicular to one of the two sides. 2. A mold equipped with a bending angle sensor according to claim 1, wherein the sensors are installed side by side and built in, and each sensor extends in the longitudinal direction of the side.