JP2000343127A - Bending equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy and perform uniform bending by means of a simple crowning means by calculating the amount of deformation in the protruding direction on the basis of work related information, product information, and processing information, and controlling the crowning means provided for deforming at the center of upper table or lower table. SOLUTION: A work is bent through the cooperation of a punch and a die by moving up/down an upper table equipped with the punch and a lower table equipped with the die. It is deformed into a convex by the deforming amount determined by a controller and the interval is uniformly adjusted. If a rotating shaft 41 is turned by a specified angle by means of a servo-motor 33, an eccentric shaft 43 turns, while being supported by support plates 15F and 15R. For this reason, the center portion 43C of the eccentric shaft 43 turns eccentric by eccentric amount α and a bearing 47 moves up/down to move up/down the lower table 9L by 2α. Since the both right and left ends are fixed to the frame and do not move, only the center portion is deformed up/down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending apparatus capable of performing uniform and high-precision bending using a compact and simple crowning means.

[0002]

2. Description of the Related Art FIGS. 11A and 11B show an example of a press brake 101. FIG. Since the press brake 101 is conventionally known, a detailed description will be omitted and a brief description will be given.

In this press brake 101, left and right frames 103L and 103R are erected, and a punch P is provided on the lower front surface on the upper front surface of the frames 103L and 103R.
Is mounted so as to be able to move up and down.

A lower table 10 having a die D mounted on an upper end surface is provided on the lower front surface of each of the frames 103L and 103R.
5L are provided. That is, referring to FIG. 11B, the lower table 10 is provided between the front and rear support plates 107F and 107R fixed to the frames 103L and 103R.
5L is provided so as to be able to move up and down only in the center portion.
09 are supported by the support plates 107F and 107R.

[0005] Further, a hydraulic cylinder 111 for crowning is provided below the center of the lower table 105L in order to improve the accuracy of the die D during bending.

On the other hand, the left and right frames 103L, 10L
Left and right hydraulic cylinders 113L and 113R are provided on the upper frame 103U bridged between the 3Rs to raise and lower the upper table 105U.

With the above configuration, the work W to be processed is positioned between the die D and the punch P, and the upper table 105U is lowered by the left and right hydraulic cylinders 113L and 113R. The work W is bent. At this time, the hydraulic cylinder 1 for crowning
11, the center of the lower table 105L on which the die D is mounted is lifted to improve the accuracy of passing the die D so that a predetermined bending angle can be obtained.

However, the hydraulic cylinder 1
In the press brake 101 using the 13L and 113R, even if the D value (distance between the blades) is calculated in advance to obtain a predetermined bending angle from work information or product information at the time of machining, the hydraulic cylinder 113L, The upper table 105U and the frame 103L as the temperature of the hydraulic oil 113R rises,
Due to deformation such as 103R, it is difficult to obtain a uniform and highly accurate bending angle.

Therefore, as shown in FIG. 12, a ball screw unit 117 is provided on the upper frame 103U for rotating the ball screw by an AC servo motor (not shown) having little heat influence to raise and lower the upper table 105U. There are things. In such a press brake 115, the ball screw unit 117
The upper table 105U is moved up and down, and the work W is bent in cooperation with the die D and the punch P.

[0010]

However, the press brake 1 using the ball screw unit 117 described above.
15, the ball screw unit 11 for raising and lowering the upper table 105U is not affected by heat as in the press brake 101 using the hydraulic cylinders 113L and 113R, but when the press brake 115 is enlarged.
7, the number of axes increases (see FIG. 12, for example, 4
Pieces). For this reason, it is necessary to control each ball screw unit 117 to keep the interval between the punch P and the die D constant, and there is a problem that the apparatus becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to pay attention to the above-described conventional technology, and to provide a bending apparatus capable of performing uniform bending processing with improved accuracy by simple crowning means. To provide.

[0012]

According to a first aspect of the present invention, there is provided a bending apparatus for vertically moving an upper table provided with a punch and a lower table provided with a die. A bending device for bending a work by cooperation of a punch and a die, wherein a crowning means provided to deform a substantially central portion of the upper table or the lower table in a convex direction, and information on the work, A control device that calculates the amount of deformation in the convex direction based on product information, processing information, and the like, and that controls the crowning means.

Therefore, when the workpiece is bent in cooperation with the punch and the die by moving the upper table on which the punch is mounted and the lower table on which the die is mounted relatively up and down, control is performed based on various information. The upper table or the lower table is deformed convexly by the crowning means by the amount of deformation determined by the apparatus, and the distance between the punch and the die is uniformly adjusted.

According to a second aspect of the present invention, in the bending apparatus according to the first aspect, the crowning means includes an eccentric shaft for deforming the upper table or the lower table in a convex direction by rotating. And a servomotor for rotating the eccentric shaft.

Therefore, when the servomotor rotates the eccentric shaft by a predetermined angle, the center of the upper table or the lower table is lifted by a predetermined amount and deformed in the convex direction.

According to a third aspect of the present invention, in the bending apparatus according to the first or second aspect, the control device includes an input means for inputting various information, and appropriately stores the input information. And a calculation unit that calculates the amount of convex deformation of the upper table or the lower table based on information input or stored in the memory and calculates the rotation angle of the eccentric shaft. It is a feature.

Therefore, in the control device, the calculation unit calculates the amount of deformation of the upper table or the lower table based on various information input by the input means and stored in the memory, and further calculates the rotation angle of the eccentric shaft. , Perform the crowning by controlling the servo motor.

[0018]

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

FIGS. 2 and 3 show the entirety of a press brake 1 as a bending apparatus according to the present invention. In the press brake 1, left and right frames 3 </ b> L and 3 </ b> R having a notch G at the center front are erected on a base 5. An upper table 9U as a ram on which a punch P is mounted is provided at the lower end of the frames 3L and 3R at the lower front portion thereof (left side in FIG. 3) via a plurality of intermediate plates 7 so as to be vertically movable.

Further, on the upper front surfaces of the frames 3L, 3R, left and right ball screw units 11L, 11R serving as ram driving means for vertically moving the upper table 9U are provided. This ball screw unit 11L, 11
In R, the ball screw (not shown) is rotated by the drive motor 13 to move the upper table 9U up and down.

On the other hand, front and rear (left and right in FIG. 3) support plates 15F and 15R are provided on the lower front surfaces of the left and right frames 3L and 3R, and a lower table 9L on which a die D is mounted is provided at the upper end thereof. It is sandwiched between the plates 15F and 15R. The left and right ends (left and right ends in FIG. 1) of the lower table 9L penetrate integrally with the support plates 15F and 15R and are fixed to the frames 3L and 3R.
Supported by R.

Therefore, the left and right ends of the lower table 9L are supported by the fulcrum pins 17L and 17R.
Although it is fixed in the vertical direction with respect to R, a slight vertical deformation is possible in the central part.

In order to raise the center of the lower table 9L by using the left and right fulcrum pins 17L and 17R as fulcrums so that the center of the support plates 15F and 15R contact the lower side of the lower table 9L, details will be described later. A crowning means 19 is provided.

A control device 21 for controlling the drive motor 13 and the crowning means 19 is provided on the left side of the left frame 3L in FIG.

With the above configuration, during processing, the center of the lower table 9L is lifted by the crowning means 19 to improve the accuracy of the die D so that uniform bending can be performed.

Referring to FIG. 3, the left and right frames 3L,
At the notch G position of 3R, a back gauge device 23 for adjusting the bending position of the work W to the position of the punch P and the die D is provided. In this back gauge device 23, a plurality of (two in FIG. 2) abutments 25 for abutting the work W are provided along the support member 27 so as to be adjustable in interval. Further, the support member 27 is provided with a link mechanism 29.
This allows for movement and positioning in the front-rear direction.

With the above configuration, the front end of the workpiece W to be machined is positioned in contact with the abutment 25 positioned at a predetermined position, and the drive motor 13 operates the ball screw units 11L and 11R to move the upper table 9U up and down. The workpiece W is moved, and a predetermined bending process is performed on the workpiece W by cooperation of the punch P and the die D.

Next, the crowning means 19 will be described with reference to FIG. In the crowning means 19, the AC servomotor 3 is connected via a box-shaped bracket 31.
3 is attached to the back surface of the rear support plate 15R.

The drive shaft 35 of the AC servomotor 33 is provided with a rotary shaft 41 in the horizontal direction via a joint 39 which is rotatably supported on the frames 3L, 3R by bearings 37. An eccentric shaft 43 in which the center of the central portion 43C is eccentric from the rotation center CL of the rotating shaft 41 by an eccentric amount α is attached to the tip (the left end in FIG. 1) of the rotating shaft 41. The front part 43F and the rear part 43R of the eccentric shaft 43 are rotatably supported by front and rear support plates 15F, 15R via bearings 45F, 45R.

A bearing 47 is attached to a central portion 43C of the eccentric shaft 43, and the bearing 47 is rotatably contacted via a hardening plate 49 attached to a lower end surface of the lower table 9L.

With the above configuration, when the rotating shaft 41 is rotated by a predetermined angle by the AC servomotor 33, the eccentric shaft 4
3 rotates while being supported by the support plates 15F and 15R. Therefore, the central portion 43C of the eccentric shaft 43 rotates eccentrically by the amount of eccentricity α, and the bearing 47 attached to the central portion 43C moves up and down, thereby moving the lower table 9L up and down by 2 · α.

On the other hand, since the left and right ends of the lower table 9L are fixed to the frames 3L and 3R by the fulcrum pins 17L and 17R and do not move up and down, only the central portion of the lower table 9L is vertically deformed within the range of 2.α. (See FIG. 4).

Therefore, as shown by the broken line in FIG. 5A, the width of the work W is large and the upper and lower tables 9U, 9
When a uniform load acts on L, the crowning means 1
9 to raise the center of the lower table 9L so that the distance between the punch P and the die D is constant (FIG. 5B).
reference).

As shown in FIG. 6A,
Even when a concentrated load is applied due to a small width of the work W, the center of the lower table 9L is similarly deformed up and down so that the distance between the punch P and the die D is constant (FIG. 6 (B)). As a result, uniform bending can be performed by improving the accuracy.

Next, the crowning operation of the press brake 1 will be described.

FIG. 7 shows a main part of the configuration of the control device 21. In the control device 21, an input means 53 such as a keyboard for inputting various data, a CR 51 for displaying various data are sent to a CPU 51 serving as a central processing unit.
An output means 55 such as T and a pressure sensor 57 for detecting a pressing force acting on, for example, the lower table 9L during bending are connected.

Further, there are provided a memory 59 for storing a machining program, data input from the input means 53, and the like, and an arithmetic unit 61 for performing various calculations required for machining. The drive motor 13 for vertically moving the upper table 9U and the AC servomotor 33 of the crowning means 19 are connected to the CPU 51.

With the above configuration, work information such as plate thickness, bending length and material, product information such as bending angle and flange dimensions,
Processing information such as the position of the punch P and the die D (for example, the eccentric position X from the center as shown in FIG. 8) is input by the input means 53, and is stored in the memory 59 as necessary.

The operation unit 61 calculates
The deflection of the mechanical system and the amount of deformation δ1 of the frames 3L and 3R with respect to the pressing force used for bending are obtained (see FIG. 9), and the upper table 9U and the lower table 9L are further obtained.
Δ2 and δ3 (see FIG. 10).

Then, the eccentric shaft 43 is rotated by the AC servomotor 33 of the crowning means 19 to cancel the obtained deflections δ2 and δ3 and to keep the interval between the punch P and the die D constant, and to adjust the center of the lower table 9L. Lift the part. The rotation angle of the eccentric shaft 43 at this time is
The calculation unit 61 calculates based on the eccentricity α of. And
AC servo motor 33 and ball screw unit 11L, 1
Bending is performed by interlocking the drive motor 13 of 1R.

From the above results, the interval between the punch P and the die D at the time of bending can be kept constant by the simple and compact crowning means 19, so that highly accurate and uniform bending can be performed. In addition, the bending work can be performed with high accuracy even on a long work W.

Also, since the crowning amount is very small,
By using the eccentric shaft 43, crowning can be performed by a small motor. For this reason, there is no need to consider oil leakage as in the case of using a hydraulic cylinder.

It should be noted that the present invention is not limited to the above-described embodiment of the present invention, but by making appropriate changes,
It can be implemented in other aspects. That is, in the above-described embodiment, the case where the crowning means 19 is provided on the lower table 9L has been described, but it is also possible to provide the crowning means 19 on the upper table 9U.

[0044]

As described above, in the bending apparatus according to the first aspect of the present invention, the punch and the die cooperate by moving the upper table on which the punch is mounted and the lower table on which the die is mounted relatively up and down. When performing bending work on a workpiece, the upper table or lower table is deformed to be convex by the crowning means by the amount of deformation determined by the control device based on various information, and the distance between the punch and the die is adjusted uniformly. Therefore, stable and uniform bending can be performed with high accuracy.

In the bending apparatus according to the second aspect of the present invention,
Since the servomotor rotates the eccentric shaft by a predetermined angle, the center of the upper table or the lower table is deformed into a convex shape.The upper table or the lower table is lifted by a predetermined amount by a simple device and deformed in the convex direction. The distance between the punch and the die can be adjusted uniformly. In addition, there is no need to worry about oil leakage unlike a hydraulic cylinder.

In the bending apparatus according to the third aspect of the present invention,
The arithmetic unit calculates the amount of deformation of the upper table or the lower table based on various information input by the input unit in the control device, further calculates the rotation angle of the eccentric shaft based on the amount of eccentricity of the eccentric shaft, Since the crowning is performed by controlling the motor, the distance between the punch and the die can be kept uniform.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a crowning means used for a press brake according to the present invention.

FIG. 2 is a front view showing a press brake according to the present invention.

FIG. 3 is a sectional view taken along a line III-III in FIG. 2;

FIG. 4 is a front view showing a state where a central portion of a lower table is lifted by a crowning means.

FIG. 5A is a front view showing deformation of the upper and lower tables for a work having a large width, and FIG. 5B is a front view showing a state in which the deformation is corrected by the crowning means.

FIG. 6A is a front view showing deformation of the upper and lower tables for a work having a small width, and FIG. 6B is a front view showing a state in which the deformation is corrected by the crowning means.

FIG. 7 is a block diagram illustrating a configuration of a control device.

FIG. 8 is an explanatory diagram showing processing information in which a punch and a die are eccentric from a machine center.

FIG. 9 is an explanatory diagram showing a deformation and a deformation amount of a frame.

FIG. 10 is an explanatory diagram showing the deformation and the amount of deformation of the upper and lower tables.

FIG. 11 is a front view showing a press brake using a conventional hydraulic cylinder.

FIG. 12 is a front view showing a press brake using a large number of ball screw units that have been generally used in the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Press brake (bending apparatus) 9U Upper table 9L Lower table 19 Crowning means 21 Control device 33 Servo motor 43 Eccentric shaft 53 Input means 59 Memory 61 Calculation unit W Work P Punch D Die

Claims (3)

[Claims] 1. A bending apparatus for bending a workpiece in cooperation with a punch and a die by relatively vertically moving an upper table on which a punch is mounted and a lower table on which a die is mounted. Or, a crowning means provided to deform a substantially central portion of the lower table in a convex direction, and calculates the amount of deformation in the convex direction based on information on the work, product information, processing information, and controls the crowning means. A control device to
A bending apparatus comprising: 2. An eccentric shaft for rotating the upper table or the lower table in a convex direction by rotating, and a servomotor for rotating the eccentric shaft. The bending apparatus according to claim 1, wherein 3. The control device according to claim 1, wherein the control device includes an input unit for inputting various information, a memory for appropriately storing the input information, and the upper table or the memory based on the information input or stored in the memory. The bending apparatus according to claim 1, further comprising: a calculation unit that calculates a convex deformation amount of the lower table and calculates a rotation angle of the eccentric shaft.