JPH06154876A - Method for detecting bending angle and device therefor - Google Patents

Abstract

PURPOSE:To provide a bending angle detecting method and a bending angle detecting device by which a bending angle of a sheet steel is accurately detected regardless of an end part shape of the shut steel. CONSTITUTION:In a bending machine 1 bending a sheet steel with a co-operation of an upper bending die 11 and a lower bending die, a AE sensor 19 detecting AE generated at the time of bending is provided, an integrator 27 integrally transforming a AE signal detected with this AE sensor 19 to an acoustic energy value is provided, and a comparing part 31 comparing the acoustic energy value integrally transformed with this integrator 27 with an acoustic energy value on a pattern table making the bending angle and an acoustic energy value preliminarily registered and stored in a storing part 29 as a parameter is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending angle detecting method and a bending angle detecting device for detecting a bending angle of a plate in a bending machine for bending a plate.

[0002]

2. Description of the Related Art As a conventional bending angle detecting device, for example, Japanese Unexamined Patent Publication No. 2-155514 and Japanese Utility Model Laid-Open No. 2-817.
There is one disclosed in Japanese Patent No. JP-A-2-155514
The bending angle detecting device disclosed in Japanese Patent Publication No. JP-A-Hei 2-81716 is provided with a CCD camera for observing the end face shape of a plate material from the right side (or left side) of the bending machine. The detection device comprises a distance sensor embedded in a V-shaped surface having a downward bending angle. The details and operation of the above-mentioned two bending angle detection devices are known and will not be described.

[0003]

However, in the bending angle detecting device disclosed in Japanese Unexamined Patent Publication No. 2-155514, the bending angle of the plate material cannot be accurately detected by the CCD camera depending on the shape of the end surface of the plate material. In some cases, there is a problem that the bending angles of various plate materials cannot be detected. Further, the use of the CCD camera has a problem that the cost of the bending angle detecting device is increased.

On the other hand, in the bending angle detecting device disclosed in Japanese Utility Model Laid-Open No. 2-81716, since the distance sensor is embedded in the V-shaped surface of the lower bending mold, the lower bending mold has the above structure. There is a problem in that it is difficult to attach the distance sensor, and the processing cost of the downward bending die becomes high.

Therefore, an object of the present invention is to provide a bending angle detecting method and a bending angle detecting device which can solve the above problems.

[0006]

In order to solve the above-mentioned conventional problems, in the present invention, in a bending machine for bending a plate material by cooperation of an upper bending mold and a lower bending mold, An AE sensor for detecting AE that occurs when bending is provided, an integrator for integrating and converting an AE signal detected by this AE sensor into an acoustic energy value, and an acoustic energy value integrated and converted by this integrator, and It is characterized in that a comparison unit is provided for comparing the bending angle registered and stored in the storage unit with the acoustic energy value in the pattern table using the acoustic energy value as a parameter.

[0007]

In the above structure, the plate material is bent by the cooperation of the upper bending mold and the lower bending mold.

At this time, the AE sensor detects an AE signal generated when the plate material is bent, and the AE signal detected by the integrator is integrated and converted into an acoustic energy value. Then, the comparison unit compares the acoustic energy value obtained by the integral conversion with the bending energy and the acoustic energy value in the pattern table with the acoustic energy value registered as a parameter in the storage unit in advance to compare the acoustic energy value of the plate material. The bending angle can be detected. In addition,
When a plurality of AE sensors are provided at appropriate intervals in the longitudinal direction of the bending die, the bending angle of the plate material in the longitudinal direction can be detected.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS This embodiment will be described below with reference to the drawings.

Referring to FIG. 4, a press brake 1 as an example of a folding machine is provided with a pair of side frames 3 standing upright and leftward (left and right in FIG. 4), and a front side of the pair of side frames 3 is provided. An upper front frame 5 and a lower front frame 7 are provided vertically (opposite to the paper surface in FIG. 4) so as to face each other. The lower front frame 7 is fixedly provided on the side frame 3, and the upper front frame 5 can be moved up and down by the operation of a hydraulic cylinder 9 provided on the side frame 3. In addition, the upper front frame 5 is provided at the lower end with an upward bending mold 11
Is provided via a die mounting member 13, and a lower bending die 15 for folding a plate material is provided at the upper end of the lower front frame 7 in cooperation with the upper bending die 11.

With the above structure, after the plate material is supported by the lower bending die 15, the hydraulic cylinder 9 is appropriately operated to lower the upper front frame 5, so that the upper bending die 11 is also integrally lowered. . As a result, a desired bending process can be performed on the plate material by the cooperation of the upper bending mold 11 and the lower bending mold 15.

The type of the press brake 1 is as follows.
The lower front frame 7 may be lifted and lowered instead of the upper front frame 5 which is lifted and lowered.

Next, the bending angle detecting device 17, which is a main part of this embodiment, will be described.

Referring to FIGS. 1, 2 and 3, the downward bending mold 15 is provided with a plurality of AE sensors 19 forming a part of a bending angle detecting device 17, and the AE sensor 19 is provided.
Has the function of detecting AE that occurs when the plate material is bent. The AE sensor 19 is provided on the front side surface (or the rear side surface) of the lower bending mold 15 as shown in FIG. 2 and on the inner surface of the lower bending mold 15 as shown in FIG. Are provided at appropriate intervals in the longitudinal direction. Furthermore, the above A
The E sensor 19 is connected to the control means 23 via a filter 21. The filter 21 has a function of filtering elements other than the AE signal detected by the AE sensor 19.

The control means 23 will be described in more detail. The control means 23 includes a control section 25, an integrator 27, a storage section 29, and a comparison section 31. The control section 25 generalizes the control means 23. In addition to the function of
5, the AE signal after being filtered by is processed into an effective value as shown in FIG. The integrator 27 has a function of integrating and converting the effective value calculated by the control unit 25 into an acoustic energy value as shown in FIG.

The storage unit 25 includes a plate material thickness, a material, a combination of bending dies 11 and 15, and a predetermined angle (for example, 90 °).
The first pattern table having the acoustic energy value at the time of bending as a parameter is stored, and bending is performed under constant conditions (the plate thickness of the plate material, the material, and the combination of the bending dies 11 and 15 are constant). Various second pattern tables with the angle and the acoustic energy value as parameters are stored. Further, the comparison unit 31 determines whether the acoustic energy value integrated and converted by the integrator 27 matches the acoustic energy value in the first pattern table stored in the storage unit 25, or the acoustic energy in the second pattern table. It has the function of performing comparison processing as to whether the values match.

The control unit 25 is connected to a cylinder operating unit 33 which controls the operation of the hydraulic cylinder 9.

An outline of this embodiment will be described based on the above-mentioned configuration.

The upper front frame 5 can be lowered by appropriately operating the hydraulic cylinder 9 after the plate material is supported by the lower bending die 15. As a result, the upper bending die 11 is lowered to move the upper bending die 1
By the cooperation of 1 and the lower bending die 15, the plate material can be bent.

When the plate material is bent, the AE sensor 19 detects an AE signal generated when the plate material is bent, and the filter 21 detects the AE signal.
Elements other than the AE signal detected in 9 are filtered. Next, the AE signal after being filtered by the control unit 25 is processed into an effective value, and the integrator 27 performs integral conversion of the effective value into an acoustic energy value.

Then, the comparison unit 31 compares the acoustic energy value obtained by the integral conversion with the acoustic energy value in the second pattern table registered and stored in the storage unit 29 in advance. Thereby, the bending angle corresponding to the same acoustic energy value as the integral-converted acoustic energy value in the second pattern table is detected as the bending angle of the plate material.

Alternatively, the comparison unit 31 compares the acoustic energy value obtained by the integral conversion with the acoustic energy value in the first pattern table registered and stored in the storage unit 29 in advance. From this, it is understood that the plate material is bent by a predetermined angle when the integrated and converted acoustic energy value and the acoustic energy value in the first pattern table match. Further, the plate member can be bent at a predetermined angle by controlling the operation of the hydraulic cylinder 9 by the actions of the control unit 25 and the cylinder operating unit 33 to stop the lowering operation of the upper front frame 5.

According to the above-described embodiment, the AE generated when the plate material is bent is detected, the AE is integrated-converted into the acoustic energy value, and the acoustic energy value after the integral conversion and the first and second patterns are obtained. Since the bending angle of the plate material is detected by comparing with the acoustic energy value in the table, the bending angle can be accurately detected regardless of the end shape of the plate material, improving work efficiency. The effect of.

Further, in order to detect the AE signal, it is not necessary to embed the AE sensor 19 in the bending dies 11 and 15,
The processing cost of the bending dies 11 and 15 does not increase, and the cost of the bending angle detection device 17 itself does not increase.

Next, the second embodiment will be briefly described.

Referring to FIG. 7, the press brake 35 according to the second embodiment is the press brake 1 according to the first embodiment.
Unlike the above, the crowning mechanism 37 is provided. That is,
An upper bending mold 11 is attached to the lower side of the upper front frame 7 through a pin 39 and an elongated hole 41, and an upper bending mold is attached to the front side of the upper front frame 5 (the front side facing the paper in FIG. 7). A plurality of pressing cylinders 43 for pressing the upper side of 11 are provided at appropriate intervals in the left-right direction (left-right direction in FIG. 7). The AE sensor 19 is provided at a position corresponding to each pressing cylinder 43 in the lower bending die 15.

Therefore, the bending angles of the plate material are moved to the left and right by individually operating the corresponding pressing cylinders 43 in accordance with the bending angles of the plate material detected by the plurality of AE sensors 19, respectively. The effect can be made substantially uniform over the entire range, and the effect of the first embodiment can be further enhanced.

The present invention is not limited to the description of the embodiments as described above, but by making appropriate changes,
It can be implemented in various other modes.

[0029]

As will be understood from the above description of the embodiments, according to the present invention, the AE generated when the plate material is bent is detected, and this AE is integrated-converted into an acoustic energy value, and further integrated. Since the bending angle of the plate material is detected by comparing the converted acoustic energy value with the acoustic energy value in the pattern table, the bending angle can be accurately detected regardless of the shape of the plate material. Therefore, the work efficiency can be improved.

Further, in order to detect the AE signal, it is not necessary to embed the AE sensor in the bending die, the processing cost of the bending die does not increase, and the bending angle detecting device itself costs. It won't be expensive.

Further, when a plurality of AE sensors are provided at appropriate intervals in the longitudinal direction of the bending die, the bending angle of the plate material in the longitudinal direction can be detected, and the work efficiency is further improved.

[Brief description of drawings]

FIG. 1 is a block diagram of control means.

FIG. 2 is a diagram showing a mounting mode of an AE sensor.

FIG. 3 is a diagram showing a mounting mode of an AE sensor.

FIG. 4 is a front view of the press brake according to the first embodiment.

FIG. 5 is a diagram illustrating the operation of the control means.

FIG. 6 is a diagram illustrating the operation of the control means.

FIG. 7 is a front view of a press brake according to a second embodiment.

[Explanation of symbols]

 1 Press Brake 11 Upper Bending Die 15 Lower Bending Die 17 Bending Angle Detection Device 19 AE Sensor 27 Integrator 29 Storage Unit 31 Comparison Unit

Claims (3)

[Claims] 1. An AE that occurs when a plate is bent is detected, the detected AE is integrated-converted into an acoustic energy value, and the acoustic energy value obtained by the integral conversion and a bending angle and sound that are registered and stored in advance are stored. A bending angle detecting method for detecting a bending angle of a plate material by comparing with an acoustic energy value in a pattern table using an energy value as a parameter. 2. A bending machine for bending a plate material by cooperation of an upper bending mold and a lower bending mold, is provided with an AE sensor for detecting AE generated when the plate material is bent, and is detected by this AE sensor. An integrator that integrates and converts the AE signal into an acoustic energy value is provided, and the acoustic energy value integrated and converted by the integrator, and the sound in the pattern table using the bending angle and the acoustic energy value registered and stored in the storage unit in advance as parameters. A bending angle detection device comprising a comparison unit for comparing an energy value. 3. The bending angle detecting device according to claim 2, wherein the AE sensors are provided at appropriate intervals in the longitudinal direction of the bending die.