JPH11179434A - Bending angle measuring method and bending method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bending angle measuring method and a bending method capable of executing high precise angle measurement regardless of a size and shape of a work. SOLUTION: When the correct measurement of a bending angle is not allowed to directly measure the work by an angle measuring instrument 3 in such a case as a work W consisting of thin and large sheets, a work W having an extremely small flange and a work W in which a louvered part or the like is provided, bending is, simultaneously with the work, executed to a test piece TP which is cut into a suitable size so that a bending angle of a stock which has the same material and moreover plate thickness as those of the work W to be bent is measured by a bending angle detector 3, and the bending angle of the work W is detected by measuring the bending angle of the test piece TP. Further, high precise bending is executed by bending the work W until it reaches the objective bending angle by the use of the bending angle measuring method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending angle measuring method and a bending method, and more particularly, to a bending angle measuring method and a bending method for bending a workpiece for which a bending angle cannot be directly measured. It is about.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
When the work P is bent by the cooperation of the punch P and the die D, it is common practice to measure the bending angle of the work W in order to confirm the processing accuracy. For example,
The bending angle is measured by irradiating the bent work W with light from the bending angle measuring device 101 and receiving the reflected light.

[0003]

However, such a conventional technique has the following various problems.

Referring to FIG. 5, when the bent work W is a thin plate and a large plate, the work W is bent by its own weight, so that there is a problem that a highly accurate angle measurement by the bending angle measuring device 101 cannot be performed. is there. In this case, even if the operator supports the bending work W, accurate measurement cannot be performed. Such a problem is exactly the same even when a contact indicator is used without using light.

Further, referring to FIG. 6, when the bent flange 103 of the work W is short, there is a problem that the measurement cannot be performed because the bending angle measuring device 101 does not receive light.

Referring to FIG. 7, when the shape of the workpiece W has a reverse bending portion 105, the bending angle measuring device 10
In some cases, measurement cannot be performed because light cannot be applied to the measurement part from 1.

Further, referring to FIG. 8, when there is a cut-and-raised portion 107 in the work W, it is impossible to accurately shine light on the measurement portion and measurement cannot be performed. Further, even when the contact type indicator 109 is used, measurement may not be performed because the probe 111 interferes with the cut-and-raised portion 107.

SUMMARY OF THE INVENTION An object of the present invention is to pay attention to the above-mentioned prior art, and to provide a bending angle measuring method and a bending angle measuring method capable of performing highly accurate angle measurement irrespective of the size and shape of a work. It is to provide a bending method.

[0009]

In order to achieve the above object, a bending angle measuring method according to the first aspect of the present invention measures a bending angle of a bent workpiece by cooperation of a lower die and an upper die. In the bending angle measuring method, the work to be bent is placed on a lower mold and cut into a size suitable for measurement by a bending angle measuring device using a material having the same springback amount as the work. Placing the test piece on the lower mold, bending the test piece together with the work, and measuring the bending angle of the test piece with the bending angle measuring device to be the bending angle of the work, It is a feature.

Therefore, accurate bending angle measurement can be performed by a direct bending angle measuring device, such as a thin and large plate work, a work with an extremely small flange, or a work having a cut-and-raised work. If it is not possible, use a material with the same springback amount, such as the same material and the same plate thickness as the workpiece to be bent, to a size suitable for measuring the bending angle with an angle detector. Bending is performed on the cut test piece at the same time as the work, and the bending angle of the work is detected by measuring the bending angle of the test piece.

According to a second aspect of the present invention, there is provided a bending method for bending a work by cooperation of a lower mold and an upper mold, wherein the work to be bent is mounted on the lower mold. A test piece cut into a size suitable for measurement by a bending angle measuring device using a material having the same springback amount as this work is placed on the lower mold, and the work and the test piece are simultaneously bent. After that, the bending angle of the test piece is measured by a bending angle measuring device, and if the measured angle does not reach the target bending angle, the bending process is further continued.

Therefore, when bending a workpiece,
For example, a test piece cut into a size suitable for angle measurement by an angle detector is simultaneously bent using a material having the same springback amount as a material having the same material and the same plate thickness as the work, and The bending angle of the test piece is measured by the angle detector, and the bending is continued until the target bending angle is reached.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a state in which a bending angle is measured by the bending angle measuring method according to the present invention. The work W is placed on the lower die D,
The bending process is performed in cooperation with the punch P as the upper die.

In this bending angle measuring method, when a work W which is a thin plate, a large plate and has a notch 1 at the center is bent, for example, the same material, the same material as the material having the same springback amount as the work W is used. A test piece TP having a small thickness and a small size is placed on the notch 1 of the work W,
Bending is performed together with the work W.

Since the test piece TP is made of the same material as the workpiece W and causes the same springback, it is considered that the test piece TP is bent at the same angle when bent simultaneously. For this reason, the bending angle is measured by the angle measuring device 3 using the test piece TP, and the measured angle is the bending angle of the workpiece W. As the angle measuring device 3, a device that is well known in the related art is used, and the description is omitted. The angle measuring device 3 may be, for example, a device using light or a contact type.

The test piece TP used at this time has a size necessary for performing a sufficient angle measurement, and has such a size that it does not bend under its own weight. For example, if the flange width is about 50 mm and the bending length is 100
mm is suitable.

FIG. 2 shows another embodiment. In this case, the test piece TP is placed near the work W of a large thin plate and bent at the same time, and the angle of the test piece TP is measured.

Next, a bending method according to the present invention will be described with reference to FIG. First, the D value (the relative distance or stroke amount between the punch P and the die D) is determined so that the bending angle becomes a predetermined angle (step S1), and the test piece TP made of the same material as the workpiece W as described above is die-bonded. D is set at a predetermined position (step S2).

Bending is performed (step S3), the load is removed, and the work W is set free to return by springback (step S4). After the test piece TP returns by springback, the test piece TP
Is measured by the angle measuring device 3 (step S5).

It is determined whether or not the measured bending angle of the test piece TP has reached a target bending angle (step S6). If the target bending angle has not yet reached the target angle, the flow returns to step S3 to bend. Continue processing. On the other hand, when the bending angle measured in step S6 has reached the target angle, the work W is taken out (step S6).
7), the bending is completed (step SE).

From the above results, when the work W is a thin plate and a large plate, it bends and accurate measurement cannot be performed. On the contrary, when the flange width of the work W is narrow and the angle measurement device 3 cannot measure the angle. Also, even when the angle measurement cannot be performed because the work W is cut and raised, the bending angle of the work W can be measured with high accuracy, so that high-precision bending can be performed.

Next, with reference to FIG. 4, a description will be given of a bending method in a case where the data of the springback amount of the test piece TP is stored in advance.

First, the D value is determined so that the bending angle becomes a predetermined angle in consideration of the amount of springback (step S).
8) A test piece TP made of the same material as the work W
At a predetermined position (step S9).

The bending is performed (step S10), the bending angle of the test piece TP is measured without removing the load, and it is determined whether or not the bending angle has reached a predetermined angle (step S11). If the angle has not been reached, it is determined that the target D value has not been reached, and the flow returns to step S10 to continue bending. On the other hand, when the bending angle measured in step S11 has reached a predetermined angle, the work W is taken out (step S11).
12) End the bending (step SE).

From the above results, if the springback amount for the same test piece TP as the workpiece W is known in advance, unloading is performed in the test bending of the testpiece TP at an angle in consideration of the springback amount. Instead, the bending angle of the test piece is measured to determine whether or not the test piece has been bent to a predetermined angle, so that quick and accurate bending can be performed.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes.

[0028]

As described above, in the bending angle measuring method according to the first aspect of the present invention, a large work made of a thin plate, a work having an extremely small flange, a cut-and-raised work or the like is provided. When the bending angle cannot be accurately measured by a direct bending angle measuring device like a work, for example, the same material as the work to be bent and the same springback amount as a material having the same plate thickness are used. The test piece cut into a size suitable for measuring the bending angle with the angle detector using the material is bent simultaneously with the work, and the bending angle of the work is detected by measuring the bending angle of this test piece. Is performed, the bending angle can be measured with high accuracy.

In the bending method according to the second aspect of the present invention,
When bending the work, the work is cut into a size suitable for angle measurement by an angle detector using a material having the same springback amount, for example, the same material as the work and the same plate thickness. The test piece is bent at the same time, the bending angle of the test piece is measured by an angle detector, and the bending is continued until the target bending angle is reached, so that high-precision bending can be performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example in which a bending angle is measured by a bending angle measuring method according to the present invention.

FIG. 2 is a perspective view showing another example in which a bending angle is measured by the bending angle measuring method according to the present invention.

FIG. 3 is a flowchart showing a procedure of a bending method according to the present invention.

FIG. 4 is a flowchart showing a procedure of a bending method according to another embodiment of the present invention.

FIG. 5 is a front view showing a state in which a bending angle of a thin and large work is measured by a conventional bending angle measuring method.

FIG. 6 is a front view showing a state in which a bending angle of a work having a small flange width is measured by a conventional bending angle measuring method.

FIG. 7 is a front view showing a state where a bending angle of a workpiece having reverse bending is measured by a conventional bending angle measuring method.

FIG. 8 is a front view showing a state in which a bending angle of a work having a cut and raised is measured by a conventional bending angle measuring method.

[Explanation of symbols]

 3 Bending angle measuring device TP Test piece D Die (lower type) P Punch (upper type) W Work

Claims (2)

[Claims] In a bending angle measuring method for measuring a bending angle of a workpiece bent by cooperation of a lower die and an upper die, the workpiece to be bent is placed on a lower die, and A test piece cut to a size suitable for measurement by a bending angle measuring device using a material having the same springback amount as above is placed on a lower mold, and this test piece is bent together with the work, A method for measuring a bending angle, wherein the bending angle of the test piece is measured by the bending angle measuring device to determine the bending angle of the work. 2. A bending method for bending a work by cooperation of a lower mold and an upper mold, wherein the work to be bent is placed on the lower mold and has the same springback amount as the work. A test piece cut to a size suitable for measurement by a bending angle measuring device using a material is placed on a lower mold, and the workpiece and the test piece are simultaneously bent, and then the bending angle measuring device is used. A bending method comprising: measuring a bending angle of a test piece; and, if the measured angle does not reach a target bending angle, further continuing bending.