JPH0618666B2 - Folding machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a folding machine such as a press brake.

[Prior Art] Generally, in a bending machine such as a press brake, the upper and lower frames to which the upper and lower molds are attached are adjusted at regular intervals,
A predetermined bending process is performed by movably controlling one of the upper and lower frames and performing positioning control at this adjusted interval.

[Problems to be Solved by the Invention] However, it is known that a frame in a bending machine is bent in accordance with its rigidity. For example, when both ends of the movable frame are driven and controlled by two cylinder devices, the bending at the center position is maximized.

Therefore, in such a bending machine, when the plate material is unevenly distributed to one side, when performing so-called one-load bending processing, even if both ends of the frame are controlled at a constant interval, the center of the frame is There is a problem that the bending is maximized in the vicinity, so that the bending angle of the end portion near the central position becomes unsatisfactory and the product accuracy is deteriorated.

[Means for Solving the Problems] In view of the conventional problems as described above, the present invention provides a lower frame having a die and an upper portion having a punch that cooperates with the die to bend a plate material. A frame and a side frame supporting both upper and lower frames are provided, and one of the lower frame and the upper frame is provided as a movable frame so as to be vertically movable, and an up-and-down actuator for vertically moving the movable frame is provided on both side frames. A position detection device is provided for detecting relative vertical positions of both sides of the upper frame with respect to both sides of the lower frame, and a drive control unit for controlling the vertical movement device is provided, and a command signal is sent to the drive control unit. Is a bending machine provided with a command setting unit for outputting processing conditions, and the command unit includes a condition setting unit for setting processing conditions, and the plate member includes the die and punch. The deflection of the upper and lower frames at the inner end position of the plate material is calculated when a load is placed on one side from the central portion, and the space between one side of the upper and lower frames and the upper and lower frames at the inner end position of the plate material are calculated. And a command value output unit that outputs a command signal to the drive control unit based on the calculation result of this calculation unit so that the intervals on the other side of the upper and lower frames are equalized. When the above-mentioned plate member is located on one side, and the load is one-sided, the vertical actuation device is arranged so that the interval between one side of the upper and lower frames becomes equal to the interval between the upper and lower frames at the inner end position of the plate member. It is configured as a control.

(Embodiment) FIGS. 1 to 3 are views showing a folding machine according to this embodiment. FIG. 1 is a side view of the folding machine, FIG. 2 is its front view, and FIG. 3 is movable. It is a block diagram of an electric circuit for frame control.

As shown in FIGS. 1 and 2, the folding machine 1 has a lower frame 3, side frames 5 (5A, 5B), and a movable frame 7 that can be raised and lowered. The folding machine 1 is of a type that bends a plate material W having a predetermined width 1 between a die 9 attached to the upper end of the lower frame 3 and a punch 11 attached to the lower end of the movable frame 7.

The movable frame 7 is the side frame 5 (5A, 5
It is connected to a cylinder 13 (13A, 13B) as a vertical actuating device mounted above b) via a piston and a piston rod 15 (15A, 15B) not shown. Movable frame 7 and piston rod 15 (15
(A, 15B) is pivotally supported so as to be slidable in the plane shown in FIG. Cylinder 1
At the upper end of 3 (13A, 13B), the servo valve 17 (17
A, 17B) are attached.

A control panel 19 is provided on one side of the folding machine 1, and an NC device NC for controlling the folding machine 1 is provided in the control panel 19.
And a movable frame control module RCM for controlling the movable frame. A pendant 21 provided on the upper front surface of the folding machine 1 is connected to the control panel 19 via a swivel duct 23 so as to be swivelable around the control panel 19 and rotatable around an attachment point of the swivel die 23. The pendant 21 is configured to be movable in the left-right direction on the front surface of the folding machine 1. An operation panel (not shown) equipped with switches and the like for operating the folding machine 1 is attached to the front surface of the pendant 21.

In the vicinity of both ends of the movable frame 7 of the folding machine 1, a linear scale 25 (25A, 2A) serving as a position detecting device for detecting relative vertical positions of both side portions of the upper and lower frames 7, 3 is provided.
5B) is attached and this linear scale 25 (25
A, 25B) facing the detection head 27 (27A, 2B).
7B) is a mounting plate 29 fixed to the lower frame 3.
It is attached to (29A, 29B). The linear scale 25 (25A, 25B) and the detection head 27 (27
The detection accuracy of the position detection device composed of A and 27B) is set to about 0.01 mm to 0.001 mm.

The folding machine 1 is provided with a foot petal FS, and the foot petal FS has a foot petal D for descending command.
S and a foot petal US for ram rise command are provided. The operator can drive the movable frame 7 in the ascending or descending direction by stepping on the foot petal FS.

The cylinder 13 (13A ₁ 13B) is supplied with oil of a predetermined pressure from a hydraulic circuit (not shown), and the servo valve 17
The movable frame 7 is controlled to a predetermined position at a predetermined speed in a predetermined direction by performing aperture control at (17A, 17B).

As shown in FIG. 3, the movable frame control module R
The CM includes a command unit 31, a drive control unit 33, two servo amplifiers 35 (35A, 35B), and two frequency voltage converters 37 (37A, 37B).

The command unit 31 has a condition setting unit 31a, a calculation unit 31b, and a command value output unit 31c. The condition setting unit 31a sets machining conditions, and the calculation unit 31b sets a predetermined condition based on these conditions. The calculation is performed and the command value output unit 31c outputs a predetermined command signal.

The condition in the condition setting unit 31a is set based on the processed data or the operation of a keyboard (not shown).
In this example, the condition contents are the width 1 and the plate thickness t of the plate material W. This is because in this example, as shown in FIG.
This is because the plate material W is positioned so as to be left-sided, and the rigidity of the frames 5 and 7 is initialized. Generally, in addition to the width 1 and the plate thickness t of the plate material, the configuration of the frames 5 and 7 and the set position of the plate material W should be conditions.

The processing contents of the arithmetic unit 31b are shown in a flowchart in FIG.

Step 401 shows the above-mentioned condition setting processing.

In step 403, it is determined whether or not the single load control is to be performed. If the single load control is performed, step 405 is performed.
Move to.

Then, in step 405, the bending load is calculated according to the plate thickness t, and then in step 407, the deflections δ ₁ and δ ₂ of the upper and lower frames at the inner end position of the plate material W shown in FIG. ₂ are calculated.

By the way, considering the upper frame 7 as a mere tension, the dimension between the connecting portions of the left and right piston rods 15A, 15B and the upper frame 7 is L, the width of the plate material W is 1, and the uniform width load M is applied to the entire width of the plate material W during processing. Is assumed to work, and the dimension from the connecting portion between the left piston rod 15A and the upper frame 7 to the left end of the plate material W is A, and the connecting portion between the right piston rod 15B and the upper frame 7 is the plate material W. Let C be the dimension up to the right end of the upper frame, E be the longitudinal elastic modulus of the upper frame 7, and I be the second moment of area, and the upper frame 7 at the dimension X from the connecting portion between the left piston rod 15A and the upper frame 7. As is well known, the deflection Y of is expressed by the following equation.

The deflection δ ₁ can be calculated based on the above equation. The deflection δ ₂ can also be calculated according to the above formula.

Here, if the movable frame 7 is controlled so that the intervals a and b of the two frames 3 and 7 are the same on the left and right sides of the movable frame 7 in FIG.
₁ , the position P _{2 at} the right end and the position P at the left end of the movable frame 7.
₃ , the position P ₄ at the right end has a positional relationship as shown in FIG. 5, and the flexures δ ₁ and δ ₂ are as shown in FIG.

As shown in FIG. 5, at the right end position of the plate material W, δ ₁ + to the left end based on the deflections δ ₁ and δ ₂ of the upper and lower frames.
This means that the bending of δ ₂ has occurred. This is the reason why the bending angle of the portion near the center of the frame is conventionally weakened.

Therefore, in step 409, a correction value χ is calculated to correct the right end frame interval b in FIG. The correction value χ is L (δ ₁ + δ ₂ ) / l when the frame length is L.

In step 411, the right side positioning data b = a−χ is calculated using this correction value χ.

Therefore, the control position of the movable frame of the correction value is as shown in FIG. That is, the frame spacing d at the right end of the plate material W having the width 1 is just a like the right end.

In this case, since the right end position of the movable frame 7 changes from P ₄ to P ₅ and the load for bending the plate material W is almost constant, the right end position P ₂ of the lower frame 3 is almost constant position. It is in. Further, the bending of the frame at this time is extremely small and is within the error range, and no consideration is required.

In FIG. 3, the command value output unit 31c sets the left end of the movable frame 7 to P based on the result calculated as described above.
_A command signal is output to position the right end at point P _{5 at 3} points (see FIG. 6).

The drive control unit 33, based on the command from the command unit 31 and the feedback signal of the detection heads 27A and 27B, moves the movable frame 7
Servo amplifier 3 until the left and right ends of reach the points P ₃ and P _5.
A predetermined voltage V is output to each of 5A and 35B. The servo amplifiers 35A and 35B control the movable frame 7 at a predetermined speed while obtaining a speed feedback signal.

As described above, the movable frame 7 is controlled to a predetermined position in the posture shown in FIG. 6, and both ends of the plate material W having the width 1 shown in FIG. 2 are bent at a predetermined angle.

In the above embodiment, the plate material W is left-justified as shown in FIG. 2, but this is the same even if it is right-justified, and as shown in step 409 in FIG. The same applies when the plate material W is positioned at an intermediate position within the frame length by changing the arithmetic expression.

[Effects of the Invention] As will be understood from the above description of the embodiments, in short, the present invention cooperates with the lower frame 3 to which the die 9 is attached and the die 9 to bend the plate material W. Punch 1
1 upper frame 7 and upper and lower frames 3,
And a side frame 5 for supporting the movable frame 7, and one of the lower frame 3 and the upper frame 7 is provided as a movable frame so that the movable frame 7 can be moved up and down. 5, a position detecting device 25 for detecting relative vertical positions of both side portions of the upper frame 7 with respect to both side portions of the lower frame 3, and a drive control unit 33 for controlling the vertical operating devices 13A, 13B. Along with this, a bending machine is provided with a command unit 31 for outputting a command signal to the drive control unit 33. The command unit 31 includes a condition setting unit 31a for setting machining conditions and the plate W for the die 9 , the deflection [delta] ₁ of the upper and lower frames 7,3 of the time piece load positioned on one side near the central portion of the punch 11 at the inner end position of the sheet material W, when calculating the [delta] ₂ In addition, the distance a between the upper and lower frames 7, 3 on one side is equal to the distance d between the upper and lower frames 7, 3 at the inner end of the plate W so that the distance d is equal. And a command value output unit 3 that outputs a command signal to the drive control unit 33 based on the calculation result of the calculation unit 31b.
1c, the plate material W is located closer to one side, and at one load, the space a between the upper and lower frames 7, 3 on one side and the space between the upper and lower frames 7, 3 at the inner end position of the plate material W. The vertical actuators 13A and 13B are controlled so that d becomes equal.

Therefore, according to the present invention, even when the plate material W is unevenly distributed to one side, the spacing between the left and right sides of the upper and lower frames 7 and 3 is individually controlled, and the bending angle on both sides of the plate material W is controlled. Can be bent so that they are equal to each other, and more accurate bending can be performed.

[Brief description of drawings]

1 to 3 show an example of a folding machine according to this embodiment. FIG. 1 is a side view of the folding machine, FIG. 2 is a front view thereof, and FIG. 3 is a servo valve. It is a block diagram of a control circuit. FIG. 4 is a flow chart showing an example of processing of the arithmetic unit, and FIGS. 5 and 6 are explanatory views of the operation of the embodiment of the method of the present invention. 1 ... bending machine 31a ... condition setting portion 31b ... arithmetic unit [delta] _1, [delta] ₂ ... vertically frame deflection W ... plate P _3, P ₅ the width of the control position L ... frame length l ... plate of the movable frame

Claims (1)

[Claims] 1. A lower frame (3) having a die (9) attached thereto.
And an upper frame (7) to which a punch (11) for bending the plate material (W) in cooperation with the die (9) is attached.
And a side frame (5) that supports both upper and lower frames (3, 7), and one of the lower frame (3) and the upper frame (7) is provided as a movable frame so as to be movable up and down and a movable frame ( Vertical movement devices (13A, 13B) for vertically moving (7) are provided on both side frames (5), and relative vertical positions of both sides of the upper frame (7) with respect to both sides of the lower frame (3). And a drive control section (33) for controlling the both up-and-down actuators (13A, 13B), and a command section for outputting a command signal to the drive control section (33). The bending machine is provided with (31), and the command section (31) includes a condition setting section (31a) for setting processing conditions, the plate material (W) includes the die (9), and the punch (11). In the center of Upper and lower frame (7 at the inner end position of the sheet material (W) at the time of single load positioned on one side closer,
3) Deflection (δ ₁ , δ ₂ ) of the upper and lower frames (7, 3) and the upper and lower frames (7, 3) at the inner end position of the plate (W) are calculated. 3) interval (d)
Based on the calculation result of this calculation unit (31b), a calculation unit (31b) that calculates a correction value (χ) that corrects the interval (b) on the other side of the upper and lower frames (7, 3) so that And a command value output section (31c) for outputting a command signal to the drive control section (33), and the upper and lower frames (7,
3) Control the vertical actuating devices (13A, 13B) so that the distance (a) on one side is equal to the distance (d) between the upper and lower frames (7, 3) at the inner end position of the plate (W). A bending machine characterized by being configured as.