JPH1076318A - Sheet metal working method, and device for correcting working machine and working operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the lowering of working precision caused on the change of sheet thickness by measuring the net weight of the cut or punched work and correcting the working operation of a sheet metal working machine based on the difference between the standard weight and the net weight. SOLUTION: An intermediate product 3b is placed on an electron scale 22 to measure the net weight. The measured value is inputted to a correction value arithmetic means 14 together with the standard weight calculated by a standard weight arithmetic means 13, the correction value of the working operation is calculated based on the difference between them or the ratio thereof. A set value set by a setting unit 21 is corrected by a correcting unit 24 based on the calculated result of the correction value arithmetic means 14, and it is given to a ram driving device of a brake press 2. Therefore, since the brake press 2 is worked in the working operation corresponding to the sheet thickness of the intermediate product 3b, the working error due to the change of the sheet thickness is avoided, and the corrective shaped product 3c is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending or drawing a sheet metal and a sheet metal processing machine such as a brake press, and more particularly to a method for correcting a processing operation in accordance with a change in the thickness of a work to obtain a product with higher precision. It is related to the technology to obtain.

[0002]

2. Description of the Related Art In the processing of sheet metal, especially in plastic processing such as bending or drawing, a variation (error) in the thickness of a work causes a variation in a processed shape. For example, when bending a workpiece to a desired angle using a brake press, measure the processing shape while processing the test piece, adjust the distance between the punch and the die in units of 0.01 mm or less, and obtain the desired processing accuracy. I am trying to put out.

[0003] After setting the interval between the punch and the die by test processing, workpieces of the same shape are processed one after another. However, if there is an error in the thickness of the workpiece, the processing accuracy is deviated.
Therefore, when processing a large number of products, a sampling inspection of the work after the processing is performed as appropriate, and when the processing accuracy is deviated, the interval between the punch and the die is readjusted. In order to prevent the occurrence of defective products, it is necessary to measure the thickness of the work with a micrometer or the like, and readjust the machine when the thickness changes.

[0004]

In plastic working of a sheet metal, there are various factors such as material composition in addition to the sheet thickness, which cause an error in the product shape after the processing. The greatest impact. This is because the composition of the material is relatively uniform for each material, and the error has a relatively small effect on the processing accuracy. This is because the error in the thickness of the sheet has a large effect on the machined shape.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a simple technique for preventing a reduction in processing accuracy due to a change in the thickness of a work to be processed in plastic processing of a sheet metal including bending.

[0006]

According to the present invention, a change in the thickness of a work is detected by measuring the weight of the work.
By correcting the processing operation of the sheet metal processing machine based on the difference or ratio between the measured value and the theoretical value calculated in the design stage, it is possible to prevent the occurrence of a processing error due to the fluctuation of the workpiece thickness. I have.

That is, according to the sheet metal working method of the present invention, the standard weight of the work 3b is calculated based on the developed shape, the design plate thickness and the specific gravity of the work 3b after cutting or punching, and the cut or punched work 3b is processed. Measure the actual weight,
It is characterized in that the processing operation of the sheet metal processing machine 2 in the subsequent process is corrected based on the difference between the standard weight and the actual weight.

In the method according to the second aspect, the calculation of the standard weight of the workpiece 3b is performed by cutting or punching the sheet metal blank 3a.
Is performed by the computer 10 which controls

The apparatus for correcting a machining operation of a sheet metal working machine according to the present invention includes a computer 10 for controlling the sheet metal cutting or punching machine 1 based on a given product shape;
A standard weight calculating means 13 for calculating a standard weight of the workpiece 3b after cutting based on the product shape, plate thickness and specific gravity data, and a scale for measuring an actual weight of the workpiece 3b processed by the cutting or punching machine 1. 22, a correction value calculating means 14 for calculating a correction value based on the standard weight and the actual weight.
And a correcting means 24 for correcting the machining operation based on the calculation result of the correction value calculating means 14.

The sheet metal working machine according to the present invention comprises a setting means 21 for working operation, a standard weight input means 23 for inputting a standard weight of the work 3b, a scale 22 for measuring an actual weight of the work 3b, Correction value calculating means 14 for calculating a correction value based on the actual value and the actual weight, and correcting means 24 for correcting the processing operation set by the setting means 21 based on the calculation result of the correction value calculating means 14. It is characterized by the following.

[0011]

In recent working machines, CNC control is widely used, and CNC control is widely used in machines for cutting or punching a sheet metal such as a turret punch press. In such a machine, the area of the workpiece after cutting can be calculated by a computer that provides processing data to the NC device. Therefore, if the design value and specific gravity of the thickness of the work are input to the computer, the standard value of the work weight after the cutting can be calculated. Since plastic processing such as bending of sheet metal is performed after cutting, the weight of the cut work is measured, and the measured value is compared with a standard value calculated by a computer to calculate the error of the sheet thickness in a proportional calculation. Can be detected. Therefore, if the processing operation of the processing machine that performs bending and drawing is corrected based on the detected error of the plate thickness, it is possible to avoid the processing error due to the fluctuation of the plate thickness of the work.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention in which a machining operation of a brake press 2 for bending a work 3b cut by a turret punch press 1 is controlled as an example. It is.

The turret punch press 1 is controlled by an NC control unit 20 connected to a CAD program 11 in a computer 10 to form the sheet metal material 3a into an intermediate product 3b having a predetermined developed shape. The shape of the intermediate product 3b is given in advance to the CAD program 11 from the keyboard 12 or the like, and the CAD program 11 can calculate the area of the intermediate product 3b. Here, the term CAD program is used to mean a program code and data.

The design thickness and specific gravity of the work are input to the computer 10, and the standard weight calculating means 13 mounted on the computer 10 in the form of a program outputs the intermediate product 3b.
The standard weight of the intermediate product 3b is calculated from the area, the design plate thickness, and the specific gravity.

When data of a plurality of works are recorded in the CAD program 11, a standard number of the corresponding work is calculated by inputting a product number from the operation panel 23 attached to the brake press 2 to correct the data. Value calculation means 1
Give to 4.

The intermediate product 3b is bent by the brake press 2 to become a product 3c. Brake press 2
There is provided a setting device 21 for setting the stroke and the pressing force of the ram, and a setting value for performing a reference operation is set in the setting device 21 based on a test processing result of the test piece. . The brake press 2 is provided with an electronic scale 22. Before bending, the intermediate product 3b is placed on the electronic scale 22, and the actual weight of the intermediate product 3b is measured.

The measured value measured by the electronic balance 22 is input to the correction value calculating means 14 together with the standard weight calculated by the standard weight calculating means 13, and the correction value of the machining operation is calculated based on the difference or ratio between the two. Is calculated. The correction value of the machining operation is calculated, for example, as an increase or decrease value of the stroke of the ram of the brake press or an increase or decrease value of the pressing force.

The simplest and most rational method of calculating the correction value of the processing operation is to perform test processing on works of various thicknesses, register the data in the correction value calculating means 14 in the form of a table, This is a method in which the thickness is calculated based on the difference or ratio between the input standard weight and the actual weight, and ram stroke and pressure correction data corresponding to the thickness are extracted.

The set value set in the setter 21 is corrected by the corrector 24 based on the calculation result of the correction value calculator 14 and is provided to the ram drive of the brake press 2. Therefore, after measuring the weight of the intermediate product 3b with the electronic balance 22,
By bending the intermediate product 3b with the brake press 2, the brake press 2 performs the processing in a processing operation according to the plate thickness of the intermediate product 3b. A product 3c having a shape is obtained.

Although the embodiment of the present invention has been described above in combination with a computer for controlling a work cutting device, the present invention can also be carried out by a plastic working device alone. FIG. 2 shows an example, and the reference numerals in FIG.
It shows the same thing as. In this example, the standard weight of the intermediate product 3b is input from the operation panel 23 of the brake press 2 and given to the correction value calculation means 14. The actual weight of the intermediate product 3b is measured by the electronic balance 22, a correction value is calculated from the measured value and the input standard weight, and the processing operation of the brake press 2 is corrected by the corrector 24 based on the calculation result. , Is exactly the same as in FIG.

When a large number of products of the same shape are continuously manufactured, the measurement of the weight of the intermediate product 3b does not necessarily need to be performed for all the intermediate products. For example, by providing a memory for storing the correction value in the correction value calculating means 14 or the corrector 24, it is possible to perform the correction by sampling and inspecting the intermediate product 3b every predetermined number, for example.

If both the turret punch press 1 and the brake press 2 are computer-controlled,
The setting device 21 and the compensator 24 of the brake press 2 can be incorporated in the computer 10 in the form of a program.
FIG. 1 illustrates a turret punch press 1 as a sheet metal outer shape cutting device and a bending press 2 for bending as a plastic working device. However, the present invention is not limited to these machines. A cutting machine can be used, and various presses for performing bending, drawing, stretch flange processing, and the like can be used as the plastic working machine.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment.

FIG. 2 is a block diagram showing a second embodiment.

[Explanation of symbols]

 1 Turret punch press 2 Brake press 3a Sheet metal material 3b Work 10 Computer 13 Standard weight calculation means 14 Correction value calculation means 22 Electronic balance 23 Brake press operation panel 24 Compensator

Claims (4)

[Claims] 1. A standard weight of a work (3b) is calculated based on a developed shape, a design plate thickness and a specific gravity of the work (3b) after cutting or punching, and the actual weight of the cut or punched work (3b). A sheet metal working method comprising: measuring a standard weight and an actual weight; and correcting a processing operation of a sheet metal working machine (2) in a subsequent process based on a difference between a standard weight and an actual weight. 2. The calculation of the standard weight of the work (3b) is performed using a sheet metal material.
2. The method according to claim 1, wherein the step is performed by a computer controlling the cutting or punching machine (1) of (3a).
The sheet metal processing method described. 3. A computer (10) for controlling a sheet metal cutting or punching machine (1) based on a given product shape.
A standard weight calculating means (13) for calculating a standard weight of the workpiece (3b) after cutting based on the product shape and the thickness and specific gravity data; and a workpiece processed by the cutting or punching machine (1). (3b) a scale (22) for measuring the actual weight, a correction value calculating means (14) for calculating a correction value based on the standard weight and the actual weight, and a calculation result of the correction value calculating means (14). A correction device for a processing operation of a sheet metal processing machine, comprising: a correction means (24) for correcting a processing operation based on the correction. 4. A processing operation setting means (21) and a work (3b)
Standard weight input means (23) for inputting the standard weight of
(3b) a scale (22) for measuring the actual weight, and a correction value calculating means (14) for calculating a correction value based on the standard weight and the actual weight,
A sheet metal working machine comprising: a correction means (24) for correcting a processing operation set by a setting means (21) based on a calculation result of a correction value calculation means (14).