JPH01271013A - Bending angle control device for press brake - Google Patents

Abstract

PURPOSE:To accurately set a relative angle between plural planes and to improve the working accuracy and working quality by performing the working of each bending part while correcting the bending angle of the later stage by the bending angle in the former stage. CONSTITUTION:As to the bending part 10, working is performed similarly to the usual bending work, the bending part 10 of the plate material P is sent forward, when the bending part 10 is abutted on a backgauge 4, out of the plate P, the bending part to be bent at later stage is disposed between the upper die 3 and lower die 2 horizontally, the plate 11 ahead from the bending part 10 is made nearly vertical standing state. Then, a pair of distance sensors to be a distance measuring mean is operated to measure the horizontal distance to the plane 11. The bending angle is obtained through this horizontal distance and the vertical interval between the upper and lower distance sensors 5. From the bending angle of this former stage, the suitable bending angle of the later stage is calculated. Then, after that, through the suitable bending angle, the elevating value to be needed to work that angle is calculated by an arithmetic processing unit 6, the upper die 3 is driving controlled through a descent value control means 7 for the upper die and upper die driving part 8.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a press brake bending angle control device, and more particularly, to a press brake used for multi-step bending processing in which a long plate material is continuously bent in multiple steps. The present invention relates to a device for controlling a bending angle.

[Conventional technology]

When bending a plate using a press brake, the bending angle of the plate is set to a constant angle depending on the groove angle of the lower die. However, due to differences in various processing conditions, such as the amount of springback depending on the material and thickness of the plate,
The bending angle of the plate material actually processed differs to some extent from the set angle of the lower die. In order to eliminate the discrepancy between the set angle of the lower die and the actual machining angle and perform bending with high precision, the amount of descent of the upper die is adjusted. In other words, the relationship between the amount of descent of the upper die and the bending angle actually processed is determined from empirical data under various processing conditions, and the amount of descent of the upper die is determined according to the target bending angle. It's about moderation.

Therefore, when performing multi-step bending of a plate material using a press brake, the amount of descent of the upper mold is set in accordance with the target bending angle for each bending step.

However, even if the lowering amount of the upper die is set appropriately in this way, there are some variations and fluctuations in the material, thickness, and other processing conditions of the plate material, so the bent angle However, it is inevitable that a certain amount of error will occur. Therefore, in the actual bending process, the above-mentioned process error is kept within the allowable process tolerance.

[Problem to be solved by the invention]

However, in the case of the above-mentioned multi-stage bending process, processing errors in the bending angle at each stage are accumulated, so that the relative angles between the surfaces that separate the multiple bending points vary considerably. There was a problem.

For example, when manufacturing a shaped product as shown in Figure 4 by multi-stage bending using a press brake, two
Consider two surfaces 11.21 separated by a bend 10.20. As shown in the figure, the bending angles of the bending portions 10.20 are θ1. θ8=90°
The two surfaces 11 and 21 are designed to be parallel, that is, to face each other at a relative angle of 180°.

FIG. 5 shows an example of processing the above product, and due to processing errors in the bending angle at each bending part 10.20,
Bending angle θ1. All of θ8 are obtuse angles larger than 90°, but each individually falls within a predetermined tolerance. However, as is clear from the figure, the relative angles, that is, the parallelism, between the surfaces 11 and 21 determined by the accumulation of both bending angles θ1 and θ2 are significantly different. In this way, if a large error occurs in the relative angle between the surfaces, the permissible parallelism tolerance will be exceeded, making it impossible to satisfy the required quality as a product.

In other words, in the case of multi-stage bending, even if the lowering amount of the upper mold is set so that the bending angle at each stage falls within the allowable tolerance, Relative angles such as parallelism between surfaces may not fall within allowable tolerances.

As described above, in conventional multi-stage bending processing, the relative angles between the processed surfaces are inaccurate, resulting in the problem of not being able to meet the required quality of the product and increasing the incidence of defective products. .

Therefore, the problem of this invention is to
It is an object of the present invention to provide a bending angle control device that can accurately set the relative angle between surfaces separated by a plurality of bending points.

[Means to solve the problem]

In order to accurately set the relative angle between arbitrary surfaces, the sum of the bending angles at a plurality of bending points sandwiched therebetween should be kept within a certain tolerance. Therefore, if the processing errors in the bending angles that occurred in the previous stage are canceled out by adjusting the bending angles in the latter stage for multiple bending points, the sum of the bending angles in both stages can be adjusted to a certain tolerance. It is possible to fit within the tolerance.

Therefore, in order to solve the above-mentioned problems, the present invention provides a press brake device that performs multi-stage bending of a plate material. (B) Calculate the bending angle in the previous stage based on the distance measuring means to be measured and the distance signal output from the distance measuring means, calculate the appropriate bending angle in the latter stage based on this bending angle, and (C) an arithmetic processing means for calculating the appropriate descent amount of the upper die based on the appropriate bending angle; and (C) an upper die descent amount for controlling the descent amount of the upper die based on the appropriate descent amount signal output from the arithmetic processing means. A control means is provided.

[For production]

In a press brake, the plate material to be bent is placed horizontally on a lower mold and a bed. At this time, the surface that has been bent in the previous step is raised with respect to the horizontal plane at an inclination angle corresponding to the bending angle.

Therefore, by measuring the elevation angle of this bent surface, the bending angle at the previous stage can be calculated.

Therefore, by measuring the distance from the distance measuring means provided in the flow direction of the plate material to the above-mentioned bent raised surface, and calculating the distance signal by the calculation processing means, the inclination angle of the raised surface can be calculated. In other words, the bending angle in the previous step can be calculated.

Since the sum of the bending angle in the previous stage and the bending angle in the latter stage is the relative angle between the surfaces at both ends, the calculation processing means calculates the bending angle in the latter stage from the predetermined relative angle and the bending angle in the previous stage. By calculating the appropriate bending angle and controlling the lowering amount of the upper mold with the upper mold lowering amount control means according to the appropriate lowering amount of the upper mold calculated based on the calculated bending angle, the bending angle in the subsequent stage is controlled. , it can be processed to the appropriate bending angle described above.

In this way, it is possible to accurately set the relative angle between the surfaces located at both ends of both bending points at any successive previous and subsequent bending steps among the multiple bending steps in the multi-step bending process. can.

〔Example〕

Next, the present invention will be described in detail below with reference to drawings showing embodiments.

FIG. 1 shows the overall configuration of the device according to the present invention, and the basic structure of the press brake is: a bed 1 on which a plate material P is placed during processing; a lower die 2 provided on the same surface as the bed 1; An upper mold 3 is provided above the lower mold 2 and is movable up and down. The plate material P is slid horizontally on the bed 1, and the bending point is placed between the lower mold 2 and the upper mold 3. A back gauge 4 is provided in front of the plate material P in the flow direction. When performing multi-stage bending using a press brake, the bending portion 10 bent in the previous stage comes into contact with the bank gauge 4, thereby setting the bending position in the latter stage. That is, the distance from the bank gauge 4 to the lower die 2 determines the length from the previous folding part 10 to the latter folding part. The basic structure as described above is similar to that of a normal press brake.

Next, the configuration of the bending angle control device will be explained.

Above the back gauge 4 in the flow direction of the plate material P, a pair of distance sensors 5.5 are provided vertically at intervals as distance measuring means. The distance sensor 5 is composed of, for example, an optical sensor, and irradiates a light beam from the tip of the back gauge 4 toward a surface 11 of the plate material P that is bent in an upwardly raised state. The distance can be measured. As the distance sensor 5, in addition to an optical sensor, various ordinary distance sensors such as an ultrasonic sensor and a magnetic sensor can be used.

The distance to the bending surface 11 measured by the distance sensor 5 is input to the arithmetic processing means 6 as an electrical distance measurement signal. The arithmetic processing means 6 includes, for example, a CPU, a storage unit,
It consists of a microcomputer equipped with input/output interfaces, etc.

The arithmetic processing means 6 calculates the bending angle in the previous stage based on the distance measurement signal, and then calculates the appropriate bending angle in the latter stage based on this bending angle. Furthermore, the appropriate amount of descent of the upper die 3 is calculated based on this appropriate bending angle. To do this, we process a certain bending angle to that bending angle based on an experimental formula showing the relationship between the bending angle and the amount of descent determined in advance from empirical data, plastic working theory, etc. A program is stored in the microcomputer that can calculate the amount of descent of the upper mold required for the above-mentioned bending angle, and the appropriate amount of descent can be immediately calculated from the above-mentioned appropriate bending angle.

The appropriate lowering amount signal outputted from the calculation processing means 6 is input to the upper die lowering amount control means 7 which controls the lowering amount of the upper die. The upper mold lowering amount control means 7 controls the upper mold driving section 8 and adjusts the lowering amount of the upper mold 3 driven by the upper mold driving section 8. The upper die lowering amount control means 7 is constituted by the same microcomputer as the arithmetic processing means described above, or by another appropriate electronic control mechanism. The upper die drive unit 8 includes a drive mechanism such as a motor and a hydraulic/pneumatic cylinder, and the upper die 3 is moved up and down by this drive mechanism.

That is, the appropriate lowering amount signal is converted into a control current etc. for the upper mold drive unit 8 in the upper mold lowering amount control means 7, and determines the amount of drive of the upper mold 3 by the upper mold drive unit 8, that is, to which position the upper mold 3 is moved. You can control how it descends as you like.

Next, a method of controlling the bending angle using the bending angle control device configured as described above will be explained.

An example will be explained in which the same product as shown in FIG. 4 is manufactured by multi-stage bending. That is,
The bent portion 10.20 is bent at an angle θ2. Assume that it is required to process the surface 11.21 so that the parallelism of the surface 11.21 is accurate. First, regarding the bent portion 10,
Process in the same way as conventional bending processing. At this time, if the upper mold 3 is driven via the upper mold lowering amount control means 7 and the upper mold driving section 8 by the microcomputer of the arithmetic processing means 6 that can calculate the appropriate lowering amount for the bending angle, The bending angle θ1 can be accurately processed.

When the previous stage bending process is completed, the bent part 1 of the plate material P is
0 is sent forward from the bending position.

When the bending part 10 comes into contact with the bank gauge 4, the part of the plate material P that will be bent at a later stage is placed horizontally between the upper mold 3 and the lower mold 2, and Surface 11 is
It will be raised almost vertically.

Next, as shown in FIG.
Measure horizontal distances YI and Y from to surface 11.

These horizontal distances Y and Y□ and the upper and lower distance sensors 5
．． From the vertical distance X of 5, the bending angle θ is determined by the following formula.

θ, = 90°+ tan-' ((Y+ Y*)
/
The appropriate bending angle in the later stage is calculated so that the plane 1 and the surface 21 are parallel (relative angle 180''). That is, the bending angles θ1 and θ in both stages are calculated.

As long as the sum is 180°, θ, = 180°−θ1 ・Old ・The appropriate bending angle in the later stage is calculated using the formula (A). Equation (1) and (A)
To summarize the formula, 0g-90'jan-'((Y+ Y,)/X
) (3), so if this calculation formula is programmed into the microcomputer serving as the arithmetic processing means 6, the appropriate bending angle can be calculated at a later stage.

Next, from the above-mentioned appropriate bending angle, the upper mold lowering amount required for processing to that angle is calculated by the calculation processing means 6, and the upper mold lowering amount is calculated via the upper mold lowering amount control means 7 and the upper mold driving section By driving and controlling the upper mold 3, the subsequent bending process is performed, and the bent part 20 is processed.

FIG. 3 shows an example of processing the plate material P processed in this way, and in the previous step of bending, the bending angle θ1 of the bent portion 10 is processed to be an obtuse angle larger than 90°. However, in the later bending process, the bending angle θ of the bent portion 20 is made into an acute angle smaller than 90°, so that the relative angle between the surfaces 11 and 21 becomes 180°. , I was able to set the parallelism accurately.

That is, as in the illustrated embodiment, if the bending angle θ in the previous stage is larger than the design angle, the bending angle θ in the latter stage is corrected to be smaller than the design angle, and vice versa. If the bending angle θ1 in the previous stage is small, the bending angle θ in the latter stage will be large (by correcting it so that the relative angle between the surfaces 11 and 21, that is, the parallelism) can be maintained. This is possible.

In the above embodiment, the bending angle is controlled so that the surfaces 11 and 21 are parallel to each other, that is, the relative angle is 180°. The relative angle of 21 can be set to any angle other than 180°. In order to change the setting of the relative angle, the arithmetic processing means 6 may change the formula for calculating the appropriate bending angle at a later stage.

Furthermore, in the illustrated embodiment, there are two bent portions 10.20 between the two surfaces 11°21, but there are three or more bent portions between the two surfaces. In some cases, the appropriate bending angle of each bending portion may be calculated from the cumulative value of the bending angles of a plurality of preceding bending portions.

〔Effect of the invention〕

According to the above-described bending angle control device according to the present invention, the relative angles between a plurality of surfaces can be set accurately during multi-stage bending using a press brake.
Since each bent part is processed while correcting the bending angle in the subsequent step based on the bending angle in the previous step, the relative angles between multiple surfaces, which were previously prone to inaccuracies and caused product defects, can be corrected. can be set extremely accurately. Therefore, the processing accuracy and processing quality in multi-stage bending processing can be greatly improved, and the reduction in product defects can greatly contribute to improving productivity.

Moreover, the structure of the control device requires only adding distance measurement means, calculation processing means, etc. to a normal press brake, so it is possible to modify and install an existing press brake, reducing equipment costs and operating costs. It's also cheap.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of a press brake equipped with a bending angle control device according to the present invention, Fig. 2 is an explanatory diagram of the operation of the distance measuring means, and Fig. 3 is a front view showing an example of the bending process. FIG. 4 is a front view showing an example of a multi-stage folded product, and FIG. 5 is a front view showing an example of a conventional folding process. 2...Lower die 3...Upper die 4...Back gauge
5... Distance sensor 6... Arithmetic processing means 7...
- Upper die lowering amount control means 8... Upper die drive section P...
Plate material 10°20...Bending part 11.21... Surface θ3. θ8...Bending angle for Figure 1, Figure 2, Figure 4 Kyoto Rokupufu official text (Spontaneous 1゜Indication of incident 0i063'f4!? Permit M100605 No. 2, Name of invention Bending angle of press brake Control device 3, relationship with the case of the person making the amendment Patent applicant address 1048 Oaza Kadoma, Kadoma City, Osaka Name (583) Matsushita Electric Works Co., Ltd. Representative Director Toshio Miyoshi 4, no agent 6, ?!Positive object 6, object of correction 111F 7. Contents of amendment■ On page 12, line 19 of the specification, "rYl -y* J" is corrected to "rY* Yl".■ Page 13 of the specification The 9th line says rYl-Y,J,
ryz-Y, correct it as J.

Claims (1)

[Scope of Claims] 1. A press brake device that performs multi-stage bending of a plate material, comprising: (A) distance measuring means located in the flow direction of the plate material and measuring the distance to the surface bent in the previous step; (B) Calculate the bending angle in the previous step based on the distance signal output from the distance measuring means, calculate the appropriate bending angle in the subsequent step based on this bending angle, and calculate the appropriate bending angle in the subsequent step based on this bending angle. (C) upper mold lowering amount control means for controlling the lowering amount of the upper mold based on the appropriate lowering amount signal output from the calculation processing means; A press brake bending angle control device characterized by: