JP3483665B2 - Method and apparatus for measuring bending angle of sheet bending machine - Google Patents

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 for a plate bending machine and a device therefor, and more specifically to a bending angle measuring method for a plate bending machine capable of measuring an accurate bending angle. And its device.

[0002]

2. Description of the Related Art Conventionally, a press brake 101 as a plate bending machine as shown in FIG. 6 has a pair of left and right side frames 103, and an upper front portion of the side frames 103 (left side in FIG. 7). The upper table 10
5 is fixed, and a hydraulic cylinder 107 is provided on the lower front side of the side frame 103.

A punch P is attached to the lower end of the upper table 105. A lower table 109 that is driven up and down is attached to the cylinder 107, and a die holder DH is provided at the upper end of the lower table 109. The die holder DH has a die D that moves up and down facing the punch P. Installed. Further, a control unit 111 that controls the vertical movement of the lower table 109 is provided.

Since it is constructed as described above, the die D
The plate material W is inserted between the punch P and the punch P, and the hydraulic cylinder 107 is controlled via the control unit 111 by a switch such as a foot pedal (not shown) so that the plate material W is bent by the cooperation of the punch P and the die D. It is a thing.

In such a press brake 101, in order to measure the bending angle of the plate material W, a detection pin 113 as shown in FIG. It is biased upward by 115. Therefore, it is possible to measure the bending angle of the plate W from the change by measuring the descending amount of the detection pin 113 by the plate W placed on the die D (Japanese Utility Model Laid-Open No. 59-68611). Has been done.

Alternatively, as shown in FIG. 8, a plurality of sensors 119 are embedded in the groove slope 117 of the die D, and the sensor 119 measures the distance between the groove slope 117 and the plate W to measure the plate W. Bending angles are measured (Japanese Utility Model Laid-Open No. 63-49327).

[0007]

However, in the case of using the above-described detection pin 113, the detection pin 113 is biased upward and the pin 113 is moved up and down to cause the die D and the plate W to move. Since the distance is measured, there is a problem that an accurate angle cannot be obtained due to the influence of the surface roughness of the plate material W.

In the case of embedding a plurality of sensors 119 in the die D, an accurate angle cannot be obtained due to the influence of the surface roughness of the plate material W as in the case of using the pins 113. Also, there is a problem that the size of the sensor 119 is restricted, which causes difficulty.

The object of the present invention has been made in view of the above-mentioned conventional techniques, and a plate bending process capable of detecting an accurate bending angle without being affected by the surface roughness of the plate. It is an object to provide a method for measuring a bending angle of a machine and its apparatus.

[0010]

According to a first aspect of the present invention, the punch and the die are brought relatively close to each other, and the tip of the punch and the both sides of the tip are positioned substantially symmetrically with respect to the punch. A plate bending machine that performs bending by bringing the plate into contact with the groove shoulders of the die formed in the vicinity of the intersection of the inclined surface of the groove of the die and the upper surface of the die and having a substantially arc shape. In the bending angle measuring method, the plate material for measuring the bending angle of the plate material from the measured vertical and horizontal components in the groove shoulder portion of the pressing force received by the die through the plate material during bending. This is a method of measuring a bending angle of a bending machine.

According to a second aspect of the present invention, in the bending angle measuring method of the sheet material bending machine according to the first aspect, the vertical component is measured from the vertical strain of the die or punch, and the horizontal component is measured. It is a bending angle measuring method of a plate material bending machine, which is measured from the horizontal distortion of the die.

According to a third aspect of the present invention, the punch and the die are brought relatively close to each other by a hydraulic cylinder, and the tip end portion of the punch and the both sides of the tip end portion are positioned substantially symmetrically with respect to the punch and have a substantially circular shape. Bending angle of a plate bending machine that bends by contacting a plate material with each groove shoulder of the die formed near the intersection of the inclined surface of the groove of the die and the upper surface of the die In the measuring method, the vertical component in the groove shoulder portion of the pressing force that the die receives through the plate material during bending is determined from the hydraulic pressure of the hydraulic cylinder, and the horizontal component in the groove shoulder portion is the strain in the horizontal direction of the die. Alternatively, it is a bending angle measuring method for a plate material bending machine, which is obtained from the pressure between the die holder and the bending angle of the plate material from the obtained vertical and horizontal components.

According to a fourth aspect of the present invention, in the bending angle measuring method for a plate material bending machine according to any one of the first to third aspects, when the bending angle of the plate material is obtained, The correlation function between the horizontal component and the vertical component in consideration of the frictional force at the contact point with the groove shoulder of the die is separately obtained, and the obtained correlation function, the horizontal component, and the plate component bending using the vertical component This is a method for measuring the bending angle of a processing machine.

According to a fifth aspect of the present invention, the punch and the die are brought relatively close to each other, and the tip end portion of the punch is positioned substantially symmetrically with respect to the punch on both sides of the tip end portion and has a substantially arc shape. In a bending angle measuring device of a plate material bending machine that performs bending by contacting a plate material with each groove shoulder portion of the die formed near the intersection of the inclined surface of the die groove and the upper surface of the die A vertical sensor for measuring a vertical component in the groove shoulder portion of the pressing force that the die receives through the plate material during bending, and a groove pressure portion of the pressing force that the die receives through the plate material during bending processing. The horizontal sensor for measuring the horizontal component, and the vertical component and the horizontal component are obtained by the signals from the vertical sensor and the horizontal sensor, and the plate material is folded from the obtained horizontal component and the vertical component. A bending angle measuring device for a plate bending machine, comprising: a calculation unit for calculating a bending angle.

According to a sixth aspect of the invention, in the bending angle measuring device of the plate bending machine according to the fifth aspect,
The vertical sensor is a vertical strain sensor that measures the vertical strain of the punch or the die, and the horizontal sensor is a horizontal strain sensor that measures the horizontal strain of the die. Is a bending angle measuring device.

According to a seventh aspect of the present invention, the punch and the die are brought relatively close to each other by a hydraulic cylinder, and the tip portion of the punch and the both sides of the tip portion are positioned substantially symmetrically with respect to the punch and have a substantially circular shape. Bending angle of a plate bending machine that bends by contacting a plate material with each groove shoulder of the die formed near the intersection of the inclined surface of the groove of the die and the upper surface of the die In the measuring device, a pressure sensor for measuring the hydraulic pressure of the hydraulic cylinder, a horizontal sensor for measuring the horizontal strain of the die or a pressure between the die holder, and a plate material by a signal from the pressure sensor and the horizontal sensor. A vertical component and a horizontal component of the pressing force acting on the die through, and a calculation unit that calculates the bending angle of the plate material from the obtained horizontal component and vertical component, It is a bending angle measuring device of a plate material bending machine comprising.

According to an eighth aspect of the invention, in the bending angle measuring device of the plate bending machine according to any one of the fifth to seventh aspects, when the bending angle of the plate material is obtained, The correlation function between the horizontal component and the vertical component in consideration of the frictional force at the contact point with the groove shoulder of the die is separately obtained, and the obtained correlation function, the horizontal component, and the plate component bending using the vertical component It is a bending angle measuring device of a processing machine.

[0018]

[0019]

[0020]

[0021]

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 and FIG. 2 show a bending angle measuring device 1 in a press brake 101 which is an example of the first embodiment. Since the press brake 101 as a general plate bending machine has been described in the above-mentioned section of the related art, the same parts are designated by the same reference numerals and duplicate description will be omitted.

A horizontal force Hf acting on the die D when pushing up the die D to bend it into a plate W is provided on one upper end of the inner wall 3 before and after the die holder DH for fixing the die D (left and right in FIG. 1). A plurality of sensors 5 such as a piezo sensor for measuring the size (see FIG. 3) are provided at predetermined intervals in the longitudinal direction of the die D. The sensor 5 is for measuring the horizontal force Hf acting on the die D from the pressure of pressing the inner wall 3 of the die holder DH when the die D is expanded and the measurement signal is provided in the control unit 111. It is transmitted to the calculation unit 7.

On the other hand, the cylinder chamber 9 of each hydraulic cylinder 107 for moving the lower table 109 up and down is connected to the electromagnetic switching valve 13 by the pipe 11 and is freely connectable to the pump 15 or the tank 17.

The pipe 11 is provided with a pressure sensor 19 for measuring the pressure of pressure oil. This pressure sensor 19
Is for measuring the vertical force Vf (see FIG. 3) acting on the die D when the lower table 109 is raised and the plate W is bent.

Next, the calculation principle of the calculation unit 7 for obtaining the bending angle of the plate W from the horizontal force Hf and the vertical force _Vf acting on the die D thus obtained will be described.

Referring to FIG. 3A, when the punch P and the die D are relatively brought close to each other to perform bending, the plate material W has a substantially arcuate shape of the groove shoulder portion DS of the die D. At the contact point S1 with the curve, it can be said that the plate material W is located in the tangential direction of the curve of the groove shoulder portion DS when there is no frictional force between the plate material W and the groove shoulder portion DS. That is, it can be said that the plate material W is in the direction orthogonal to the normal line of the curve of the groove shoulder portion DS.

Further, since the force of the plate material W pushing the die D acts in the normal direction at the contact point S1, the die D
When the direction of the resultant force f acting on is calculated, it can be seen that the plate material W exists in the direction orthogonal to the resultant force f.

Therefore, as shown in FIG.
= A / 2 = tan -1 (Vf / Hf), the bending angle A
= 2 · tan −1 (Vf / Hf).

Here, since the vertical force Vf is received by the groove shoulder portions DS at the front and rear of the die D, it is half of the total vertical force F obtained by the pressure sensor 19. The horizontal force Hf is obtained by the pressure detected by the sensor 5 and the distance between the sensors 5 in the longitudinal direction of the die D.

As described above, the groove shoulder portion DS of the die D and the plate material W
If the correlation function β between the horizontal force Hf and the vertical force Vf is calculated separately considering the frictional force at the contact point with and other uncertain factors, the bending angle is A = 2 · tan −1 (β・
Vf / Hf).

As described above, since the sensor 5 is not provided directly on the groove slope 117 of the die D but is provided on the die holder DH side, the size of the sensor 5 is not limited and the sensor 5 can be easily provided.

Further, even during bending, the bending angle can be measured without being influenced by the surface roughness of the plate material W, and accurate bending can be performed.

Further, the accuracy of the plate W can be measured from a plurality of sensors 5 provided in the longitudinal direction of the die D, and high-quality bending can be performed.

Next, FIG. 4 shows an example of the second embodiment.
In the example of the first embodiment described above, the vertical force Vf was obtained from the pressure of the pressure oil, but in the example of the second embodiment, the vertical force Vf is measured by the strain sensor 21 provided on the punch P.
It is designed to obtain f. Other configurations are exactly the same.

Even in this way, the bending angle can be measured without being influenced by the surface roughness of the plate W even during bending as in the case of the above-described first embodiment, and an accurate bending can be performed. The present invention can be applied to a processing machine that can perform the bending work without using the hydraulic cylinder 107 for the bending work, and can perform the bending work with the structure of the motor, the crankshaft and the like.

Next, FIG. 5 shows an example of the third embodiment.
In the example of the third embodiment, as shown in FIG. 5A, a sensor 23 such as a strain gauge, a semiconductor sensor, or a load cell is provided on the groove shoulder portion DS of the die D to directly apply a vertical force. Vf and horizontal force Hf are obtained.

Further, as shown in FIG. 5 (B),
Along the longitudinal direction of the die D, for example, a plurality of dividing positions 25
By providing the sensor 23 in such a case and measuring the bending angle of the plate material W, it is possible to obtain the same effect as the above-described first embodiment example and second embodiment example.

The present invention is not limited to the above-described embodiments, but can be implemented in other modes by making appropriate changes. For example, although the press brake 101 is described as a bending machine in the example of the above-described embodiment, the invention is not limited to this.

Further, although the press brake 101 of the type in which the die D side is raised to perform the working has been described in the above-mentioned first embodiment, the same applies to the type in which the punch P side is lowered to perform the working. Is.

Further, by providing a rotatable roller or the like on the groove shoulder portion DS of the die D so as to eliminate the frictional force at the contact point with the plate material W, the bending angle can be obtained more easily and with high accuracy. it can.

Further, in the example of the above-mentioned embodiment,
The vertical component and the horizontal component were measured by separate sensors, but the same operational effect can be obtained even if one sensor is used to measure both the vertical direction force and the horizontal direction using a triaxial strain gauge.

[0044]

As described above, in the bending angle measuring method for the plate bending machine according to the present invention, the die is bent when the plate is bent by bringing the punch and the die relatively close to each other. The vertical component and horizontal component of the pressing force received by the plate material at the groove shoulder are measured, and the bending angle of the plate material is calculated from the measured vertical and horizontal components. An accurate bending angle can be obtained without being affected by the surface roughness of the plate material as in the case of obtaining the angle. Also,
Since the installation position is not limited to the inside of the die, there is no restriction on the size of the sensor.

In the bending angle measuring method for a plate bending machine according to the second aspect of the present invention, the vertical component is measured from the vertical strain of the die or punch, and the horizontal component is the horizontal strain of the die. It is not necessary to provide a sensor inside the die, and the size of the sensor is not limited.

In the bending angle measuring method of the plate bending machine according to the third aspect, when the punch or die is relatively moved by the hydraulic cylinder to bend the plate, the vertical component acting on the die is described above. Since it is obtained from the hydraulic pressure of the hydraulic cylinder and the horizontal component is obtained from the horizontal strain of the die or the pressure between the die holder and the die holder, it is not necessary to directly provide a sensor on the die, and the size of the sensor is not restricted. Further, unlike the case where the angle is obtained from the distance between the die and the plate material, the bending angle can be accurately obtained without being influenced by the surface of the plate material. Further, in the bending angle measuring method of the plate material bending machine according to claim 4, considering the frictional force at the contact point between the plate material and the groove shoulder portion of the die,
The bending angle of the plate material can be obtained.

In the bending angle measuring device of the plate bending machine of the invention according to claim 5, when the plate material is bent by bringing the punch and the die relatively close to each other, the vertical sensor measures the vertical component. The horizontal sensor measures the horizontal component, and the calculation unit calculates the bending angle of the plate material from these vertical and horizontal components, so the accurate bending angle can be obtained without being affected by the surface roughness of the plate material. You can

In the bending angle measuring device for a plate bending machine of the invention according to claim 6, since the vertical component and the horizontal component acting on the die are obtained by the vertical strain sensor and the horizontal strain sensor in claim 5, the groove portion of the die is obtained. There is no need to provide a sensor on the inclined surface, and there is no size restriction.

In the bending angle measuring apparatus for a plate bending machine of the invention according to claim 7, when the punch or the die is relatively moved by the hydraulic cylinder to bend the plate, the pressure sensor causes the hydraulic cylinder to move. Since the hydraulic pressure is measured and the horizontal sensor measures the horizontal strain of the die or the pressure between the die holder and the die holder, it is not necessary to provide the sensor on the slope of the groove portion of the die, and there is no size restriction. In addition, the calculation unit receives the signals from the pressure sensor and the horizontal sensor to obtain the vertical component and the horizontal component acting on the die, and calculates the bending angle of the plate material from the obtained vertical component and the horizontal component. As in the case of obtaining the angle from the distance between the die and the plate material, the bending angle can be obtained accurately without being influenced by the surface roughness of the plate material. Further, in the bending angle measuring device of the plate bending machine according to the eighth aspect, the bending angle of the plate can be obtained in consideration of the frictional force at the contact point between the plate and the groove shoulder of the die.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a first embodiment of a bending angle measuring device for a plate bending machine according to the present invention.

FIG. 2 is a front view seen from the direction II in FIG.

FIG. 3 is an explanatory diagram of a principle of obtaining a bending angle from a vertical component and a horizontal component of pressing force.

FIG. 4 is a sectional view showing an example of a second embodiment of a bending angle measuring device of a plate bending machine according to the present invention.

FIG. 5 is a sectional view showing an example of a third embodiment of a bending angle measuring device for a plate bending machine according to the present invention.

FIG. 6 is a side view showing a press brake as a bending machine.

FIG. 7 is a cross-sectional view showing a conventional bending angle measuring device.

FIG. 8 is a cross-sectional view showing a conventional bending angle measuring device.

[Explanation of symbols]

1 Bending angle measuring device 5 Horizontal sensor 19,21 Vertical sensor 23 Horizontal sensor 101 Press brake (plate bending machine) 107 hydraulic cylinder P punch D die DS groove shoulder DH die holder Vf vertical component Hf horizontal component f resultant force W plate material

Claims (8)

(57) [Claims] 1. A punch and a die are brought relatively close to each other,
The tip of the punch is located substantially symmetrically with respect to the punch on both sides of the tip and has a substantially arc shape, and is formed near the intersection of the inclined surface of the groove of the die and the upper surface of the die. In a bending angle measuring method of a plate material bending machine for bending a plate material by bringing the plate material into contact with each groove shoulder portion of the die, the vertical force in the groove shoulder portion of the pressing force received by the die through the plate material during the bending process. A method for measuring a bending angle of a plate bending machine, which comprises measuring a component and a horizontal component and determining a bending angle of the plate from the measured components. 2. The bending angle measuring method for a plate bending machine according to claim 1, wherein the vertical component is measured from a vertical distortion of a die or a punch, and the horizontal component is horizontal distortion of the die. A method for measuring a bending angle of a plate bending machine, which is characterized by measuring from 3. A punch and a die are brought relatively close to each other by a hydraulic cylinder, and the tip portion of the punch is positioned substantially symmetrically with respect to the punch on both sides of the tip portion and has a substantially arc shape, and has a groove of the die. In the bending angle measurement method of the plate material bending machine, which performs bending by contacting the plate material with the groove shoulders of the die formed near the intersection of the inclined surface of the die and the upper surface of the die, The vertical component in the groove shoulder portion of the pressing force that the die receives through the plate material is obtained from the hydraulic pressure of the hydraulic cylinder, and the horizontal component in the groove shoulder portion is the horizontal strain of the die or between the die holder and the horizontal component. A bending angle measuring method for a plate bending machine, which is obtained from pressure and the bending angle of the plate is obtained from the obtained vertical and horizontal components. 4. The bending angle measuring method for a plate material bending machine according to claim 1, wherein when the bending angle of the plate material is obtained, the plate material and the groove shoulder portion of the die are A plate material bending machine characterized by separately obtaining a correlation function between the horizontal component and the vertical component in consideration of frictional force at the contact point, and using the obtained correlation function and the horizontal component and the vertical component. Bending angle measurement method. 5. A punch and a die are brought relatively close to each other,
The tip of the punch is located substantially symmetrically with respect to the punch on both sides of the tip and has a substantially arc shape, and is formed near the intersection of the inclined surface of the groove of the die and the upper surface of the die. In a bending angle measuring device of a plate material bending machine that performs bending by contacting a plate material with each groove shoulder portion of the die, the vertical force at the groove shoulder portion of the pressing force received by the die through the plate material during bending. A vertical sensor for measuring a component, a horizontal sensor for measuring a horizontal component in the groove shoulder portion of the pressing force that the die receives through the plate material during bending, and a signal from the vertical sensor and the horizontal sensor A plate bending process, comprising: a vertical component and the horizontal component, and an arithmetic unit that calculates the bending angle of the plate from the horizontal component and the vertical component thus obtained. Bending angle measuring device for machine. 6. The bending angle measuring device for a plate bending machine according to claim 5, wherein the vertical sensor is a vertical strain sensor for measuring the vertical strain of the punch or the die, and the horizontal sensor. Is a horizontal strain sensor for measuring the horizontal strain of the die, and is a bending angle measuring device for a plate bending machine. 7. A punch and a die are brought relatively close to each other by a hydraulic cylinder, and a tip portion of the punch is positioned substantially symmetrically with respect to the punch on both sides of the tip portion and has a substantially arc shape, and has a groove of the die. In the bending angle measuring device of a plate material bending machine for bending a plate material by bringing the plate material into contact with each groove shoulder portion of the die formed near the intersection of the inclined surface of the die and the upper surface of the die, the hydraulic cylinder Pressure sensor for measuring the oil pressure of the die, a horizontal sensor for measuring the horizontal strain of the die or the pressure between the die holder, and a signal from the pressure sensor and the horizontal sensor to act on the die through a plate material. The calculation unit calculates a vertical component and a horizontal component of the pressing force to be applied, and calculates a bending angle of the plate material from the calculated horizontal component and vertical component. Plate and bending machine bending angle measuring device. 8. The bending angle measuring device for a plate material bending machine according to claim 5, wherein when the bending angle of the plate material is obtained, the plate material and the groove shoulder portion of the die are A plate material bending machine characterized by separately obtaining a correlation function between the horizontal component and the vertical component in consideration of frictional force at the contact point, and using the obtained correlation function and the horizontal component and the vertical component. Bending angle measuring device.